OPERATION PLUMBBO “MEVADA TEST SITE j MAY~SESTEMBER 1957 : . ? ° 2 .y = : ey a . < oe ‘ W Proct3.200 kt EVALUATION of BURIED CONDUITS. as PERSONNEL SHELTERS - aie Date: july “, 1980 NEAOOGARTERS FIELO CORRARE i Rh =—oDEFEMSE ATOMIC SUPPORT AGENCY : mp SANDIA BASE, ALGHOSZRQUE, KEW MEXICO ‘ a a + ? oe < " 3 . e t ° be 7 4 ‘ ‘ _ ” » 2 e ‘, atts on a eee ry ay t Pid 4 3 Wh t rfid “e ays . a . ~ ’ at ‘ “4 a! . Xa oe < fe f *~ ~ ek, te Breure teh. ~s yj ars » ane , ' . ~~ wpe wo en ie * ’ on Oy rsd iv ~tAPm>ap. “7 2 Aye ot ~~, re - woe Ca rege ’ Cre POS aS ye Se: e on See, Ged «te Sie gt so Le i ee - a -¢ a og “ ~° ¥, \ a iM ; s # i we SS DISCLAIMER NOTICE THIS DOCUMENT IS BEST QUALITY PRACTICABLE. THE COPY FURNISHED TO DTIC CONTAINED A SIGNIFICANT NUMBER OF PAGES WHICH DO NOT REPRODUCE LEGIBLY. NOTICE TO USERS Portions of this document have been judged by the Clearinghouse to be of poor reproduction quality and not fully iegible. However, in an effort to make as much information as possible avaifable to the pub- lic, the Clearinghouse sells this document with the understanding that if the user is not satisfied, the document may be returned for refund. If you retum this document, please include this notice together - with the IBM order card (label) to: eo er 5 Springfield, Va. 2215i t' oe we Wr 1421 OPERATION PLUMBBOB— PROJECT 3.2 EVALUATION of BURIED CONDUITS as PERSONNEL SHELTERS G.H. Albright, LTJG, CEC, USNR, Project Officer J.C. LeDoux, LCDR, CEC, USN R.A. Mitchell, LTJG, CEC, USNR Bureau of Yards and Docks Navy Department Washington 25, D.C.- , and U.S. Naval Civil Engineering Laboratory Pori Hueneme, California hae EPS ae eh 8 eye SS OR Lt E, SE ESE EE ee ae hate eee ee : ES ae kata Tis 2 oe sae 7% tte FORE ORD a This report presents the final results of one of he 48 projects comprising the military-eifect program of Operation Plumbdod, which included 24 test detonations at the Nevada Test Site in 1957. ; For overall Plumbbob military-effects infor: cation, the reader is referced to the “Summary Report of the Director, DOD Test Group (Prog: ams 1-9), * ITR~1445, which includes; (Da description of each detonation, including yield, | A.9 Compacting back{:1l with gasol: 1e-driven vibrating roller - -------+--+----- $1 B.1 Deflection gage scribing asgen dly -----+-----+----- we ec nc ecccccows $4 B.2 Scratch deflection gage install 2 inside conduit - - ----- eee eee eee nen ene 56 B.3 B.A B.5 B.6 B.7 B.8 Typical scratch gage installati. n ----- 22-22 en ee eee wwe ceren= §§ Self-recording pressure-time gage - -- -- ee +2 + eee ee ee ewe eewneneee 35 Self-recording pressure-time yage mounted in concrete base --------+--+- 56 Peak pressure gage installed on timber bulkhead at access- end of condvit --------------- weerewcewsascccecaccenacce 58 Calibration of electronic accelcrometer --~----<- cc cence creer co neon 89 Electronic accelerometer (left) and self-recording accelerometer (rig! t, installed in cuncrete Conduit 3.21 ----cc-ccee-~ 59 B.9 Self-recording peak accelerometer instatled on bottom of concrete conduit---------+--<+- ------- a. P.10 Styrofoam missile trap inside con rete conduit ------- eee reecncnen- = 3 3.11 Dust co'lectors installed inside concrete conduit- - «~+- -s----e- ese we- 6] B.12 Deflection records, Conduits $.2a, 3.24, and 3.2e -----------en-n ene Bi B.13 Deflection records, Conduits 3.2, 3.2c, and 3.2f -----e--<-eeeeeene= 81 B.14 Deflection records, Conduits 3.2¢, 3.2h, and 3.2} -------- weenennnnn- 63 B.15 Deflection records, Conduits 3.2k, 3.21, and 3.2m ------------see---- 62 TABLES 2.1 2.2 2.3 2.4 2.5 3.1 3.2 3.3 A.l f.2 Arrangement of conduits at Test Site, Shot Priscilla ------- ---ccess--- 14 Description of Tert Conduits - -------22-.-----2- wccceaiccccces 14 Properties of 10-Gage Corrugai sa Steel Plate veded the peak overpressures at the carth surface. Thereforc, the information obtained at that time could not be used to estimate strictural behavior or nuclear radtation protection afforded be closed-end buried conduit sections. It has been indicated (Refererce 2) that some of the principal ways in which the sarth cover over buried structures can act include (1) changing the pattern of distribution of the forces oa the structure by changing the effective shape of the structure or (2) permitting the tranefer of forces around, bet rot through, the structure. [t has also been stated (Reference 3) that whe deflections become large, as in many cases of flexible structures, arching begins to be effective after the deflections have reached valucs corresponding to about 5 percent of the span. Reference 4 indicates that the design of buried structures (conduits) based on stress analysis is not ; ossible because of the great uncertainty tn the pattern of forces on the conduits. The change in shape of flexsble structures and the arching action of the soil cannot be presently evaluated to permit 2 rational analysis for dynamic loads. Reference 5 reports the development of empirical design theories by means of field teste over a pertod of years at a large number of varied installations. For Operation Plumbbob, test sections, typical of portions of a multinle-tube (Figure 1.1), or emergency shelter, were selected by means of modified static design procedures and on the basis o' steadard commercially available material. The soil used for backfill consisted of a gravelly-saity-sand mixture crom borrow pits, more ncarly representing 2 lypreal backfill material such as may be found af continental | S. and overzea Lase locations, rather than the rs dry-lake bed material found uw Frenchman Fi. : inaemuch as DOD Classes Land Il protecti: 1 assumes protection againat comparable effects (thermal radiation, nuclear radiation, etc.) it xas destred to obtain an index of radiation shield- tng afforded by conduits arraaged with various iepths of earth cover. ft was planned that an evaluation of the vari us zections for use as typical sections of person. Poseegeces Figure 1.2 Possible arraggement of conduits as persons! shelters. nel ehelters would be made from (1) maxtmum ind residual changes tn vertical diameter, (2) residual change in horizontal diameter, (3): ternal peak pressures, (4) vertical acceleration of condvits, (5) pamma and neutron-radiation lh els, (6) inissile and dust hazards, and (7) gen- eral examination, M was anticipated that the conduits located to receive 100-psi or greater overpressure would possibly provide adequate Class I protection and that the conduits located to receive 50-pst or greater overpressure would provide Class iI protection, including effects from radiations. 12. Chapter 2 PROCEDURE 2.1 DESCRIPTION OF CONDUITS ‘Twelve 20-foot long closed-end conduit sections, completely buried, with 5 to 10 feet of earth cover, were subjected to Shot Priscilla of Operation Plumbbob. They were arranged as midieated in Tables 2.1 and 2.2 and Figure 2.1. Each structure was so arranged and was of suc length as to preclude the action of end restraint from interfering with its response. To vermit installation and adjustment of instrumentation after burial of test sections, access passages of fabricated corrugated-steel sections were provided as 2 simple, economical test configuration. These were closed with a steel plate and sandbays tu prevent blast pressures from entering the conduit and to permit valid nuclear radiation measurement to be made in the actu..! test sections. Inasmuch as the objectives of this project include evaluation of test sec- tions of conduits only, such an entrance was definitely not designed for operational use as a part of a shelter. The general arrangement of the access passage (test operation purposes only) for all con- duits is shown in Figure 2.2. Both ends of each test section were provided with a closure (designed solely fur the purpose of this experiment) consisting of 10-by-12 inch wood timbers assembled into a diaphragm by means of 2-by-4 inch wood members and steel angles. Strips of Y,-inch thick asphaltic impreg- nated composition buard were nailed to the wood diaphragms, on the side adjacent to the conduits, to insure a tight seal and to correct any surface irregularities. At one end cf each conduit, an access passage was attached, and an opening reinforced with steel angles was provided in the wood bulkheads. Typical end bulkhead arrangements are shown in Figures 2.3 and 2.4. A 1-inch steel plate was used as a hatch. This was covered with 4 feet of sandbags inside a 5-foot-square plywood box without top or bottom. The wood box is shown in Figure 2.5. The bedding and backfill operations were performed in a manner typical to « onveational coa- “struction practices. The backfill was carefully placed in nominully 6-inch lifts, and compacted with hand-operated pneumatic tampers and other mechanical equipment, as explained in Appendix A. tngeneral, the backfill material used was a gravelly-silty-sand material similar to that utll- ized over the Operation Teapot 3.6 corrugated-metal structure (Reference 4). This backfill material, rather than the dry-lake bed material found in Frenchman Flat, was used to more nearly represent backfill material typical of continental and oversea base locations. Thus, the data obtained would be more pertinent to the proposed use of conduits as personnel shelters, and possibly more easily correlated with previous data collected on the Operation Teapot Proje ect 3.6 structures (Reference 4). During backfilling operations, density and water-content data were obtained by the Water- ways Experiment Station (WES, Projcct 3.8), Also, mechanical analyses of the soil were per- formed by WES, and ck-mical and spectrographic analyses were performed by the U.S. Naval Civil Engineering Laboratory (NCEL). Analyses of the soil used, compaction data, and details of backfilling operations are included in Appendix A, Section A.3. 2.1.1 Corrugated-Steel Cattle-Pass Conduits. Conduits designated as 3.22, 3.2b, 3.2c, 3.22, 3.2g, 3.2k, and 3.2m in Table 2.2 consisted of curved and flat 10-gage corrugated~-steel sections assembled into cattle-pass shapes, 20 feet long, arranged as indicated in Figures 2.6 and 2.7. The properties of the corrugated plate sections (Reference 6) are given in Table 2.3. Typical inte~ior and exterior views of a test section are shown as Figures 2.8, 2.9, and 2.10. 13 TABLE 2.1 ARRANGEMENT OF CONDUITS AT TE sT SITE, SHOT PRISCILLA 47 kt yreld, 700 feet Seight of burst. Range from Topographic Predicted Station 7 Ground! Zero Slant At :le of a Theoretical Condut Coc niinates Number to center of Range $ ght is Tast Overpressure Structure at Earth Surface ft yda deg psi 9018.01 3.2a 970 389 36 746,889.76 715,271.62 125 9016.08 os a | 1,040 418 34 748,819.76 715,130.58 100 9016.03 B.2¢ 1,04¢ 418 34 748,868.75 715,164.43 100 9016 01 ach 1,040 418 34 746,915.74 715,201.66 100 9016.05 3. 1,150 449 31 748,625.82 714,284.17 76 5016.06 tum 1,360 510 7 746,686.76 714,722.71 50 9016.07 uk 1,360 $10 7 748,987.70 714,339.35 50 O27 ot B.ze 1,040 418 4 747,003.73 715,284.11 100 9017 02 3.2) 1,150 449 19 746,677.78 714,933.14 15 9017.03 Bee | 1,360 810 7 747,007.69 714,871.34 50 9018.01 3.2d 1,040 418 34 748,961.73 715,242.36 100 9018.02 3 2h 1,150 449 31 746,602.80 714,906.08 75 TABLE °.2) DESCRIPTION OF TEST CONN TS Sise Cini rece + “ae Material Taternal Internal Width Haight TER ee RL We ee ae ape t in tin $20 7.5 Steel Cattle Pa: Corrugated Stuc! 5 10 7 8 .2hb 10.0 Steel Cattle Par Corrugated Steol Hy 10 q 8 $.2¢ 1.5 Steot Cuttle Par Corrugated Stew § WwW 7 #8 sez 7.5 Steol Circular Corrugated Steol 8 8 = 3.26 7.4 Concrete Circu r Precast Concrete & = s— Ha f 5.0 Steel Cattle Pa: Corrugated Steel 5 10 7 8 8. op 7.5 Steel Cattle Pa: Corrugated Stee! 5 10 7 §& we2h 7.5 Steel Circular Corrugated Steel 8 — Ss = 3.2) 7.5 Concrete Circu w=: Precast Concrete 8s — 8s — 3.2k 7.5 Steel Cattle Pa: : Corrugated Steel 5 10 7 8 3.21 7.6 Concrete Circu ur Precast Concrete 8 — 8s — 3.2m $.0 Stee! Cattle Pa: 3 Corrugated Stsel § 10 7 8 / of. + “yo Project 3.3 Structure med (Reference 13) F - 3.2 - 9017.03 F-3,2-9017.01 (3.2000 (3.20)0 F-3.2-9018.01 F-3.2-S016.07 (3.200 (BR2k)a 7 F ad ‘ L— Project 3.3 Structures —°y ? (3.20.4 a (Reference !3) M 4 4 J Y P-32~-9016.03 (3.2c)a f~3.2~90!6.02 #7 (3.29)8 ACCESS IW F-5.2-9016.08 (3.2 A WF = 3.2--90!17,02 (3.2,:)0 ~ G2 F~3,2-9019,02 > (3.2h) @ & Cottle Poss F- 3.2 -9016.05 ; (3,2g)4 O Circuler Concrate @ Circular Steet o~m= Depth of Cover Figure 2.1 Plot plan, Project 3.2 15 *peayypng szaquiy) pua-pasojD ¢°g 21nB}q *suo}jerado 389} 203 pasn adessed Ssa2zy yg amnd7 $39QWI) 21:0! ae Sos i 2 oe he we ee me Bulkhead 10"XI2" Timbers - Figure 2.4 Access-end timber bulkhead. aa “wary Se > alae Se so aD LS ee Oe Be Figure 2.5 Entrance tc test condutts. “4 ne “Sts 3; ‘al, BS) _ a ae we ee Ate: a iv |\—l- Metal cattle poss 2} feed mA 1 : \ es ovet TY a RE ran y | % NE SE A Wo”, os: \ iz V/ “ x TH .t\y a4 + 1/ Sandbogs ——F-> i els ’ i] ke] ; rime eC AION B-8' BIS vores ers, % GOCS —~——— -- : a S 3'-Q" dio. pipe mi ~age) ay ’ Leg 10 gage Corr. Steel : : é os wah? SECTION A-A B eres Figure 2.6 Cattle-pass test section and access parseze. Figure 2.7 Assembled sh2)): of cattle-ness soction. 18 ROL I stew oiote TABLE 2.3 PROPERTIES OF 10-GAGE CORRUGATED STEEL PLATE ee ee ee 272 Depth Neutral: Aus a nome ee es 6 Pith -——- es Thickness (inch) 0.3945 Tangent Length (inch) 1.8606 Angie in Degrevs and Minutes = 44° (00' Moment of Inertia (tach 4 * 0.9372 Area of Sectton (inch?) © 2.003 geet! m Modulus (inch?) ¢ 0.8784 Radius of Gyration ({ack) 0.684 * Per foot of borizontal length of conduit. Figure 2.8 Interior view of typical cattle-pass conduit, showing scratch deficction gage at mid-length. 19 : ‘ : Figure 2.9 Exterior view ol cattle-pass section prior to backfilling. Figure 2.10 Interior view of cattle-pass section showing timber end closure. 20 a CSE 2.1.2 Corrugated-Steel Circular Structures. Structures designated ax 3.2d and 3.2h in Table 2.2 were standard 10-gage corrugated-ste: | sections of 8-foot diameter. The properties of the steel plate sections were identical to those given for the cattle-pass sections in Table 2.3. Each 20-foot long test section consisted of three basic plate lengths assembled as indicated in Figures 2.11, 2.12, 2.13, and 2.14, 2.1.3 Reinforced-Concrete Circular Conduits. Conduits designated as 3.2e, 3.2j, and 3.21, in Table 2.2 were standard concrete sewer pipe (Reference 7) having the properties indicated in Table 2.4. 7 Each 20-feot long test section consisted of two 8-foot and one 4-fyot sections grouted at the . eer ' Grade Line i \ f * Fill Natural > ig Soil \ sia 64 Earth Cover / va ® Timber Bulkhead Weed Ladder PLAN Figure 2.11 Circular steel test section and access passage. time of assembly. The conduit sections were assembled as indicated in Figures 2.15, 2,16, 2.17, and 2.18. 2.2 DATA REQUIREMENTS 2.2.1 Structural Measurements. The structural instrumentation for this project consisted of instruments to measure the transient air overpressures at ground surface, peak internal pressures, peak and dynamic acceleration of bottom of conduits (ali by Ballistic Research Laboratories, BRL Project 3.7) and the change in vertical diameters by NCEL. Four electrouic channels were utilized for the dynamic-acceleration measurements. A summary of structural instrumentation is shown in Table 2.5. The specific locations of the instruments in the conduits are shown in Figure 2.19. Data reliahility, description of instruments, and conclusions regarding instrumentation are presented in Appendix B. 21 " Figure 2,12 Exterior view of circular steel conduit prior vo installation of access passage. Figure 2.13 Interwe view of typical circular steel conduit. 22 on In order to aid in the evaluation of the « (fectiveness of test sections for use as sheltera, 2 erilical dimensions were determined by surveys made approximately 18 days before the shot, 9 days after the shot, and again 113 days .fter the shot. Measurements included croes section shape, and absolute lucation below an established mark at the entrance tunnel section. The Figure 2.14 Interior view of circular steel uection showing timber closure. specific iccations and magnitudes of such measurements are indicated in Section 3.1 and Appen- dix B, Section B.1. A series of preshot and postshot photographs were made to aid in evaluation of postshot conditions. 2.2.2 Environmental Hazards. For this tes. particular attention was given to thoes effects defined as personnel environmental hazards inside closed underground conduits, specifically: TABLE 2.4 PROPERTIES OF CONCRETE TEST SECTION a Standard Specification ASTM 75-65 Internal Diameter 96 inches Shell Thickness 9 inches Concrete Strength (minimum) 3,000 pei Total Steel Area: Clreumferentizi 2 lines totaling 0.§7-inch® per linear foot Ell'ptical Noae, steel placed conceatrically only ee re TST TE A A EE PS TD acceleration effects, internal pressure effects, missile hazards, and dust hazards (in concrete conduits). ‘ Accelerometers were meunted on the bottom of the conduits to provide acceleration meas~- “-o urements. Peak-pressure gages were installed inside each structure to serve not only as a 23 Notural Fx Sort P = . oe Figure 2.16 Exterior view of typical circular concrete conduit prior to backfilling. *pua ssad0e 3 aInsoOLD zaqwy Suyaoys *yNPUOd ayarsu09 FEND.179 20]2988 WUNpUOD AVINIZTD yO MAJA LOTIIIVT QT" OLNSTg TEdGA, PO MOSA POPLINE ETE aandy7 25 check for structural behavior due to leakage but also as a check for pressure hazards to per- . sonnel, Photographs served aluo as documentation in connection with potential missile hazards (bolts, connecting angles, ete ). Inasmuch as dust is a knowa environmental personnel hagard and because no data exist ref- TABLE.2.8 STRUCTURAL INSTRUMENTATION SCHEDULE Number Type Location 12 Deflection Gages (Scratch) One ta each of 12 coaduite (at top) 4 Self-recording Preegure-Time Cundult $.2a (125 pet) Gages (on earth ourface) Conduit $.2b-¢ (100 pst) Conduit $.2h-g (75 pei) Conduit 3.2! (60 ps!) 12 Poek Bernal Pressure Gace One in each of 12 condu‘te t2 Peek Accelerometers Cne {n each of 12 conduits (Vertical Component) 4 Electroaic Dynamic Acceler- One in Conduit 3.2a (125 pet) ometer (Vertical! Compunent) One in Conduit 3.2f (100 pai) One in Condult 3.2g (75 pel) One in Conduit 3.21 (60 pe!) erable to closed underground structures subjected to shock from atomic weapons, the Lovelace Foundation (Project 33.5, Reference 8) conducted a field investigation which included three conercte conduits of this project. The objectives for this study were to (1) document the particle . sizes of preshot and postshot dust and (2) differentiate, if possible, the sources of the postshot 5'=0" Ove. Corr Pips Tunnel (8 Cage) OLAN Figure 2.19 Typical gage location inside test section. dust; whether or not particles after the detonation arose {rom existing dirt on the floor of con- duits or actually spalled from the conduits or bulkheads as a result of the shock. Two types of dust collectors were installed in 3.2e, 3.2j, and 3.21. Results are indicated in Section 3.2, and ‘ a detailed explanation of the dust collectors is included in Appendix B. 26 Figure 2.20 Interior view of cattle-pass section showing aluminum tube used to house neutron-threshold device. Figure 2.21 Exterior view of Conduit 3.2f prior to backfilling. Nole 8-iach steel pipe used as recovery tube for neutron- threshold device, As . part of the investigation of possible spalling eifects of large missiles, missile traps ox were installed also in Conduits 3.2e, 3.2), and 3.21 by the Lovelace Foundation (Project 33.2, Reference 9). Styrofuam was used as missile receivers. Results are discussed in Section 3.2, and additional details are included in Appendix B. 2.2.3 Nuclear Radiation Instrumentation. The nuclear radiation shielding measurements were provided by the Chemical Warfare Laboratory (Project 2.4, Reference 10) and consisted of the following: Gamma film packets All 12 conduits Chemical neutron dosimeters All 12 conduits Neutron threshold devices Conduit 3.2f The specific location of the nuclear radiation measuring devices within the various conduits 18 indicated in Section 3.3, and details of the specific measuring devices are furnished in Appendix C, Section C.2, The neutron-threshold devices, attached to a %-inch steel cable, rested in a 4-foot-length aluminum pipe section inside the conduit. The cable passed from the aluminum section through an 8-inch steel pipe extending from the end of the conduit, making a 45-degree turn toward the surface to approximately one foot below the ground level. The ¥%,-inch cable terminated in a cap covering the end of the steel pipe. To the opposite end of the cap was attached a ¥%-inch steel cable. which in turn was attached to the Project 2.4 master cable. The recovery tube for the neutron-threshold measuring device was provided to permit extraction at H + 45 minutes of those particular radiation shielding measuring devices for which early time of recovery was essential. The recovery tube is shown inside the structure in Fig- ’ ure 2,20; an exterior view prior to backfilling is shown ia Figure 2.21. In order to completely define the shielding material, an elemental analysis of the soil used for backfill was made by NCEL and is included in the Appeadix, Section A.3.1. Results of the ‘ shielding measurements of the conduits are included in Section 3.3 and the Appendix, Section C.4. 28 ween a: ae oF ~*~ Chapter 3 ; RESULTS \ 3.1 STRUCTURAL MEASUREMENTS Structural measurements are tabulated in Tables. 3.2 and 3.2. Da tails of the instrumentation used are included in Appendix 6. Measured peak overpressures aere st mewhat zo eater than predicted. Overpressures were measured directly over or adja ent to on y sex of the conduits. The overpressures thus obtained are indicated w Table 3.1, as deny applizable also to the other six condutts at the corresponding ranges from ground zero. Recorded peak internal pressures rane from 1.0 to 3.7 psi but the reliability of these data is questionable. Ail recorded downward accelerations of conduit bottoms were less than 10g. The values of 8 and 5 g’s at conduits 3.2a, 3.2f, and 3..g are considered good records. ‘The other accelera- tion records are questionable but fall witl in about (he game range. In comparison, Reference fb reports free-field peak downward acct lerations of 7.0 and 4.2 g’s followed by peak upward ‘ accelerations of 4.1 and 3,5 ¢’s respectively at 10 feet below zround surface and at a range of 1,350 feet. In making such 2 comparison it must be remembered taut a soit different from the ; native #renchman Flat soil was used as backfill around the conduits. Measured durations of ‘ downward acceleration were 50, 48 and 43 milliseconds at Structures 3.2a, 3.2f, and 3.2g, : respectively. Preshot measurements of conduit dimensions were made on D-18 days and postshot meas- urements were nade on D + 9 days and D + 113 days. Recorded cunituit dimensions from th first two surveys are given in Table 3.2. Changes in conduit dimensions as indicated by the two postshot surveys are given in Table 3.1. Full scale scratch gaye deflection traces are in- cluded in the Appendix, Section B.1. The fact that some of the survey measurements do not ingree with corresponding scratch gage rev-ords indicates a definite experimental error in one or the other. Nevertheless, a close exaniination of these data reveals several interesting tendencies. Scratch gage records indicate that the crown of two of the cattle-pass type conduits sprang back to a relative residual position higher than their initial position. The other cattle-pass conduits ad residual relative vertical deflections at the crown of from 29 tv 53 percent of their maximum vertical defiection, In comparison the circular concrete conduits and the circular steel conduits had residual relative vertical deflections of from 20 to 50 pecvent of maximum and from 97 to 67 percent of maximum, respectively. Except for ove conduit, the chanye in internal herght of condutt as measured by a D+ 9 days survey is consistently greater than indicated by the scratch gaze records. No explanation us offered for this diserepancy. The D 4 9 days survey indicated that the width of the cattle-pass conduits decreased (net) during the period from D-18 days to D + 9 days. During the same period the net change in the width of the circular conduits was either an increase or zero. The D + 113 survey indicated no significant change in conduit height. In al! flexible metal conduits there was a tendency for the circumferentiat dimension to : reduce because of slipping of corrugated plates at the seams. In no case was a sheared bolt observed. The cattle-pass sections in gen2ral appeared :v experience greater slippage than the circu.ar sections, The sl:ppage of any one joint was not greater than oP inch. he ee ae Se EE wove “ABINDI}D MOLWUVOD eGhLg -seinasq9 teow -adhLE -eevd onyes teeg -edhLs ‘Gg xipusddy 908 ‘prose: sjezdwooul , : t= % my wy Loan my > at _- 09 os oesTos §=— fuze ot- , Nee %,. ba % et et 195°0 08 e% eeetos = stee 1- m. % by %. % @t> or _ ry) 2 sostcs = ANZ S i HI- 0 %,_ Mr oy, be > ee _ oot 2 eoatcs = sfere ; 0 Y,, hs Yes y 1) > et sss 0 oor ss seetos § = 8aze %- ° % %, %. 1%, os et eee’ ot 2 ee-ptes = 4 Sze J ". ” %. MY, y % es oe _~ 921 es Seerce = byes o ¥1~ %, Ye. Wy. %. oy > os _ 92t 8 testes «= g ozs ee %. 0 Nes. yp. y_ oY, — preces o ot _ ery ee teeres «= tere : I= A ". %. my ots. > oe e020 ert 2 tostos = sore “ Ys %. Mey ey. %. %, &> Piose2 070 = gaz 6 ot e'ot postos = A Gz-¢ . %,. oy, Wee ,,. me oN - os ae stz'e cor $8 Vorstoce = saz er ) uy ut uy uy ut 2 30 oes 1ed - Aoasng skeq saseH sete5 : 6 + GO Ws; 1NJOg 3 a as Pacagietik ae eee a YnV29g Yows9g Paes eunseorg Pies 4 hina 4eaog @0ud 19394 07 a6 c wos) a013 onOg Jo ba que aequinn exneiay wonog Wwosy YIN wosy 143} wr0.ty yyBI ON uonssyeq vonsayeg UONBIeOODy —s TrULoIU} jo esnesord P mda wonnng wNpuLED vInpues jo feuseiuy feuroruy Teusjquy feonsay jeoj1294 Premanog yeog corresag “18040 on ua sAoHy $8039 ut efueys ur a8ueya ut a8uey5 lenpreay tununxepg yeeg Sr1N1}90g yrag Teer “UIPIM 10 IYS}ay Ut VORSNp|t 40 ‘uoNoaYep prkAuNOp e — “HIPPA 40 Ysjaq Uy SxearoN] JO ‘uONSOTEp prem a4 SLN3NZYISVEM TVUNLONABIS Ie 3TAVL - ey sr os * TABLE 3.2 SURVEY MEASUREMENTS 32 4,¢,n5,8 32 6.0,6,%,6,8,.0 Sections KK Conduit Time® Dimeesions rm A B c D E F G vi fin | of ole to. a. in, in. ft. & in. i Pe 1% 8 8% 92% 63% 68% _ 6 10% " ° post it 1% 3 0% 1% 8% 68% #4— 7 0% i Pre ol 8 8 3% 935% ea, 63% _ 9 9% 2. P 3° post 1k 1%, 8 8% 92 2, es _ s 9% A Pre ot 1% 9 2% 92% «3% 69! _ 7 3% 4 32e post 1 2 91% cP hA 63 69% _— 7 8% " sca (PRO BY, 8 3% 98% a, 96%/, esl, 7 71% S Pot 11 7% 8 8% 3% 6% 3% 8 95 7 71% ty es o% ti 5% 98 9%, 96 2% 7 8 © Post 99 0% = .1s4% 3% «66% 8 «696% 6% tT 6% f sar eee ES 8 8% 92% 3% 68 _~ 4 10% ft ; Post 11 7% 8 8% 92 eo, 0% — su ) Pre 10 1% 10 2% 92% a3, 69's —_ 7 3 ; 578 post 10 1% 10 2&% 93% 63%, 89% a 7 3% % oa Pre 11 8% 8 8 96% 93% s4'4 6% 7 2% : Post 1 8 8 8 98", es, 94%, oe, 6 8 , oe Pre 91% 14% 93% 6 9% 96, 7 4% te Post 1% 1 4% 93% * 26%, oe 7 3% ‘ eae Pre «or 7% 8 6% 92% es 69%, _ 6 ul : Pott 12 7% 8 a% 92 63% 69% —_ 7 3% t gai SEP 91% an 4% 9s % 3% 9 7 3 hy Post 9 2 1 4% 08% 26 96% 6 7 38h _ Pre ot e% a 7% 2% 8% o% — 4 10% age ee ay, 8 7% 92% 68% 69% — 4 6% . * Preghot measurements of D- 18; Poatshot measurements on D+ 9. ; 31 t oe 2 8 6 @ e @ e 2 “a oe, ” qTaonaoddad LON *y[NpUOD Jo tWop}0q Ie YOeLD uOysuay YouT-"/, aon *yousysod ‘ag’e MNpPUoOD azasouOd jo MATA JOJIOW] Z°g ONT A al Le Ae (ik ak tie adder *yoysead ‘az’e yNpUod 93029009 JO MATA JOFIOW] 1°¢ 91N3g a Taicndowdad LON *yoys}sod ‘yous tod (Z°g WNpUOD Jo ur0z30q Uy HOeI *yousisod ‘fg-e yNnpu0oD *‘ag’e WNpudD yo woo uy woes touy-B/ yo dn-asoqD ¢’g aandrg DJPITUOD JO MAJA JOPLIWY pre amyz yous -¥, fo dn-asor9 ¢°¢ arnt 4 Ye B GPS TDF wa Laan wero $3 *“payjousur A;,uapiss0 s9,9WISOp seBu07 yi § “pauounaisur won , nen o OX S9°L Ot x ZO"! + OX S9°% Ol * Z0°t + OLX S9°Z 01 * 20°! 5 Z22Z2Z 2zZ2Zz the) mno La nt st X 92't s O1*SE*t Ol X92 : ot se"! Ol X 921 , OXSE! mmwn 301 * 29" _ 1X 681 0! * 291 5 OX 68"1 <0! * 29°} 2 OFX 68° sO! * 29°F = Ol * 68°t 30! * 79° s Ol * 68°i onMmMnoa ° oOoRKR ARO RAN 4 > N N N N N fo] QoaOOOn ooo oo N 201 * Zp°! 3 Ol *SE°z der 2 he ww ~ Jajewisod = pompat saisuysoq ax" fwoyrtoy Hed = feopuraqy balk | osog uwo71n9eN asog wade s80g BOIKEN arog wuaEy 29A09 T1"4 BY ice SwwatainstaK playa 901g J qideq wnpucyd VY uonses 0-8 i ee 2005 —— «9199909 ws f 7] so uldag SLNAIWZYASVAN NOILVITVY HVFIDAIN fe 3TAVL Crock Legend Crock Legend O= Harshine Os Hartine @ + 1/32" wids @s 1/32’ ode &2 1/16°° 1/4 nds Figure 3.6 Crack survey of top half, Figure 3.7) Crack survey of bottom half, developed; concrete Conduit 3.2, developed; concrete Condutt 3.2¢, Paco 5 Rue aang Siete Crock Legend oO » Harrtine Figure 3.8 Crack survey of top half, developed; concrete Conduit 3.2). = ~ act Crock Legend Os Hairline @ = 1/32" wide Figure 3.9 Crack survey of bottom: half, davelogec; concrete conduit 3.2). \ a 2 \ ae Pt Bis “Crack Legend a © 3 Hairtine Crack Lega.d Oo Hairline @ = 1/32" wide Figure 3.10 Crack survey of top half, Figure 3.11 Crack survey of bottom half, developed; concrete Conduit 3.21. developed; concrete Conduit 3.21. 37 Preshot and postshot photographs of the interior of two of the concrete conduite are showa in Figures 3.1 through 3.5. Significant crack» uw urced in one concrete conduit (3.2e). The cracking in the other two concrete sections was barely noticeable and is hardly detectable on photographs, consequently crack pattern drawings for all cuncrete conduits are tncluded in the form of developed sections as Figures 3.6 through 3.11. The entrances to all test sections and all timber bulkheads were in excellent posishot coa- dition. 3.2 ENVIRONMENTAL HAZARDS A smali amount of dust and wood splinters accumulated on the fallout trays and micreecopic slides placed in the concrete conduits. No missiles, such as spalled concrete or mortar, were observed in any of the missile traps placed inaide the concrete conduits. The duet and wood splinter samples obtained will be analyzed and zignificant findiags will be reported in the Op- eration PlumSbob Project 33.5 final report. Those structural measurements which .uwribute to environmental hazards (eccelerationa and internal pressures) are presented in Section 3.1, 3.3 RADIATION MEASUREMENTS On this project, netther direct thermal radiation sor neclear radiation from fallout were of Significance, consequently, the radiation of inlerest consisted of {nittal gamma and noutrea radiation. Results are presented in datail in Appendix C. The gamms and neutron doses are . summarized in Table 3.3. Free-fisid newtron-flux data are included in Reference 12. e at Chapter 4 DISCUSSION Complety scrateb deflection records were ootamed wi nine conduits, partial scratch deflection records were obtained i three conduits, and even of a tutabot twelve titernal-presaure gages recorded. ALL dynanue accelerometers fun tioned, however, seli-recorduy: tcc elorumeters used as backup for cleetrunic measurements produced somewhat questionable values, It was not possible to recover the neutron threshold device from Conduits 3.20at D+ 45 min - utes as plained; however, radtalion measurements trom. a chemical dosimeter im thes condutt provided a valid reading. The neutrun-threshold device was lodged in the recovery tube be- c.tuse of excess sand entering the capped crd of the tube, An identical recovery-tube arrange -~ ment, however, wurked verv Jatisfactorily in sdjacent structures of Operation Plumbbob Proj- ect 3.3 (Reference 13). Photographs and survey measurements pruvided sufficient documentatiun uf general postshot condition and residual deformation of the conduits respectively. 4.1 STRUCTURAL ADEQUACY OF CONDI ITS The structural measurements have been presented in Chapter 3. rhe criterion for struc- tural adequacy in this case is that the structure matatain ds geaeral form and stubilaty, thot ts, that the structure does net collapse, and that deflections are not great enough to preclude the succesatul performance of the structure as a prolective shelter. None of the cunduits col- lapsed and niaxunum changes in conduit heyght were about one inch. Thus, the test results indicate the structural suitability of the Conduits for use as personnel shellers, sf used under conditions identical lo those ot this test. If prese ' knowledge will permit, itis very desirable to make general conclusions that are appheable to other conditions, To do this, tt os necessary to have an understanding of the re- action of the vartous soils lo air-blast loading, the reaction of the structure to the resultant soul loading, und the interaction of the structure response and the soil reaction, The remain- ing paragraphs of this section discuss this in more detail. 4.1.1 Soads Acting. An arr-blast load induces a4 round shock wave which is propagated through Ue soil to the structure. This ground shock wave interacts with the buried structure cuisiig the strecture to deform. The deformation of the structure hae a mayor effert on the contact pressure al the soid-structure intertace, For this test, measuced free-fleld overpressures rangéd from 60 to 2l9 ps tad durations were from 206 to UE msec, ‘The air pressure wave lorm was characterized by a sharp rise ab pressure toa tirst low peak followed by a phueau or a slyht decay, Chen a second much- busher pe uk, followed by a decay lo zero pressure (Reference f4). 0 The came interval between intial arrival of the air blast and peak overpressure was of the order of 50 tu 100 msec. Thus, the loads acting at the ground surface are known to teot accurary but the carth s.resses acting on the structures were not measured and are not known. If a semi-infinite homogeneous elastic medium is subjected to an air blast, the maximum vertical stress at any depth is the same as the applied air blast, the vertical strain is propor- tional to the stress, and the instantancoun particle velucity is properti mal to the instantanevus siress (Refcreuce 15). But the assumoties of at truly elastic medium implies no energy loss in the transmission ol a stress wave. iteference 15 states, “tots known that the dyn. ate stress- | | | ~a se =< — wy strain curve in earth presents « considerable hysteresis loop, representing a dissipation of energy. This luss probably results largely ia the eating away of the shock front, increasing the rise time wilh increasmy depth. ” ifa semi-infinite homogencous soil masy is subjected to a step function luad of infinite dura- tion, the ultimate vertical stress at any depth is the same as the applicd load. But, as stated by Reference 16, “In the real case, the finite velocity and duration of the blast wave cause an attenuation of peak stress with depth. This attenuation is obviously a function of duration and should be less with longer durations, but the nature aud magnitude of thes function are not evi- dent from presently avatlable data, The peaked form of the impel also pernuts reflections from layers of diffevent avoustic ampedance to effect the shape and magnitude of the stress wave”. We know from atomic field tests that for relatively short duration blasts over silty Frenchman Flat sotl, there is some attenuation of free-field peak acceleration with increases in soil depth (References Ll and 15). For the same conditions other investigators have observed an attenu- ation with depth of pressure acting on a buried stress yage or structure (Refcrences 3, 17, 18, and 19). ‘The amount of reduction of pressure depends on the flexibility of the structure (Ref- erences 3 and 19). The field test data do not agree as to the rate of attenuation with depth, particularly in the first few fect. Measurements made by Operation Upshot-Knothole Project 1.4 (Reference 17), using Carlson-Wiancko carth stress gages at 1-, 5-, and 15-foot depths, suggest a logarithmic oF an inverse power attenuation of vertical earth stress as a function of depth. Some 1- and 5- fool deep gages indicated an apparent earth stress greater than the surface air overpressure. Nat, according to Reference 17, the near surface data was erratic and less dependable than the data from the 15-foot deep gages. In contrast, measurements made by Operation Plumbbob Project 1.7 (Reference 19), using a calibrated 2-foot diameter diaphragm as a yage, suggest that the rate of stress attenuation is greatest in the first few feet beluw .round surface. For quite different conditions at Enitwetok Proving Ground (EPG) the observed results were somewhat different. The two EPG detonatione were at the ground surface; one produced a rel- atively tong duration blast, the other a relatively short duration blast; and the soll at EPG is predominately coral sand with the water table only a few feet below ground surface. Free-field data taken at EPG indicates greater attenuation with depth of local airinduced acecleration than at NTS (Reference 16). The same investigators observed that air-induced geound shock waves were refracted through the earth, from remote lucalions nearcr ground zero, to contribute significantly to earth acceleration readings. Beyond 2 certain range the earth transmitted wave front outran the air blast wave, thus masking locally air-induced effects. Preliminary data obtained by another project prompted the following conclusions quoted from Reference 20: “The data suggests that there existy a considerable effect of structure flexibility on the pressures on structures buried both above and below the water table in this soil,” and, “The data also sugyests that a large-magnitude surface burst can produce very-large borizontal water-transmitted pressures, which will be grealer than the air-induced pressures below (he water table,” Operation Hardtack Project 3.2 tested two varth covered 25-foot span corrugated steel 180- degree rch structures, one subjected to 90-psi overpressure frum a kiloton-range detonation and the other subjected to 78-pst from a meyation-range detonation, Reference 21 reports “Since (he two are shells were identical and the confining earthworks were almowt identical, the fact that Structure 3.2b suffered complete collapse at 78 pst (long-duration loading), and Structure 3.2Za sustained extensive localized damage without complete collapse at 90 pst (short duration loading) is significant, ” : With the exception of References 3 and 17 the references cited above are preliminary test reports subject to further analysis, development, and possible revision, These preliminary reports do, however, point out some of the many variables that may effect the alr-induced ground load acting on a buried structure, for certain limited test conditions. But a quantitative understindirg of the effect of all significant variables is required before the test data can be used to pred:ct pressures resulting under other conditions. 4.1.2 Response of Structures. A buried conduit type struct ue has 2a certam inherent strength = due tots form aind malernl Charactertat es. Butt at isa relatively flexable structure as were the steel cond.iG. tested, i must depend on the sutroundiip sert tor a lerge part of ats strength. Reintorced coucrete carcubtr conduits are rctatively less Hesible thin steel conduits 2nd there - lore desend upon the surrounding sel toa lesser decree. A buried crecuher (exible condiit subjected to blast load tends first to deform inte an ellip- tical shape. Both the passive earth pressure and the aur-blast induced ground pressure cestst this deformation. Tlais possible for higher forme of deflectiar with aore stress reversals to take place, depeuding upon the loading, the characteristics of the structure, and the deforii- fan chatueteristes of (he surrounding sou. Scrateh-gage records midteate a nuiximunt tran stent reduction ta internal hegsht of the circular stect conduit of 0.8 and 0.9 percent. Survey taeasurements imdicate thad thas type conduit became more ellipti al shaped duruy the periud fram D- U8 days to Ded days. Some of the change in vertical dinmenain ts ee doubt due ta Jount shappagee, | Seratcleg ace records indicate & maxumunt transient reduction ia internal herzht of the cir- cular concrece conduits of 0.3 and 0.6 percent. Survey measurements indivate (hat this type condat also eeame more clliptical shaped duruys the pertud from D-18 days to D +9 days. Note that the peak transient reduction in height is sc mewhat less than that for the circular steel conduits. But an exanunation of the survey data given im Tabte 3.2 will show changes in shape of the concrete conduit as great as those for tue steel cowuit, It is reasonable to be- heve that the coucrete conduits tested gained some ..trength frum the passive soil resistance although it was probably considerably less than did the more Hexible steel conduits. Scralch-vane records indicate maximum transient reductions i ateraal height of the steel ‘ cattle-pass type structure of frum 0.3 to LA percent. Syrvey data tdicates 4 decrease in width of (his type conduit durtny the period from D— 18 days t¢ D+9 days. This suggests the possibility that thin type conduil essumed a high for.a of deflection shape characterized by ‘ several stress reversals around its periphery. Unfortunately, Cransteut measurements of change tn width of any of the conduits were not taken. 4.1.3 3 Extrapolation of Results. Present knowledge is not sufficient to permit direct extrap- olation of these test data to other conditions. The loads ac tings on the ground surface during the tes are Known to a reasonable accuracy. But the loads act'ng at the suil-structure inter- face are definitely net know. Since a gravelly-silty-sand material, rather than the natural Frenchman Plat soil, was used for backfill, the attenuation data obtained by other Ope~ation Plumbbob projects 18 aot valid for this project. References 16, 20, and 21 indicate some of the great differences in loading and response to be cxpected for conditions differing from those existing during Operation Plumbbot. | | 4.2 INTERNAL ENVIRONMENT CONSIDERATIONS 4.2.1 Acceleration, Peak downward accelerations of Sy and 8¢ with durations of about 50 mace were measured at the conduit floor. An upward acceleration of smaller peak magnt- tude followed the wuttal downward occeleration., For different soil snd detunation conditlons a completely ditercat magnitude, duravion, direction, and sequence of scceteration loadiys as possible (Reference 16), Heference 22 tates that for human beings the folerable limit of acceleration depends to a Breat extent upon the manner in which the forces arising act on the body. This reference re- ports studies made to determine the tolerable limits of acceleration on a human strapped into an aircrafl-type seat. The investigator reports that a person so supported can tolerate 20's : deceleration of a forward moving seat for a duration of a few hundred millweconds without injury. The same studies revort that a man 50 supported can withstand an upward acceleration ‘ of the seat of u» tv about 20g 3 for 100 msec without Injury. But 1° cannot be assumed that She ter occupants will be so vell supported. Obviously, no genera! statement can be made ; 4l : OER onan eee a CEE 6, im OS Par aera COMI | LOE ad sae Ns ew ew = Bn eal ee ene regarding acceleration cffects on personnel withoul considering the manuer in which the result- ing forces act on the pe sonnel. if the accelerations measured im this test are thought to be excessive for certain shelter uses, their effect could be reduced by inslalling the necessary shock isolation mechanisms inside the structure. 4.2.2 Pressure. Peak-pressure gazes indicated overpressures of up to 3.7 psi inside the conduit sections but the reliability of these data 1s questionable. Reference 23 reports that the atomic explosions in Japan during World War H resulted in “no cases of direct damage to internal organs by the blast among the survivors although there were sume ruptured eardrums.” This reference also states, “The air blast overpressure required to cause rupture of eardrums appears to be highly dependent upon circumstances. Several observations indicate that the minimum overpressure 1s in the range from 10 to 15 pounds per square inch, but both lower and higher values have been reported.” Even if over- pressures were as high as 3.7 pst in ‘Ne test conduits, it ig very unlikely that such a condition would be hazardous to personnel. A possible explanation for the internal pressures is that they were caused b~ a leakage be- tween the individual wood members of the bulkhead used. The endwalls were nut intended to serve as endwalls of an actual shelter; they were included only to provide an economical ead closure for the test sectton. An impregnated joint {iller strip was used between the test sections o: the conduits and the bulkheads to avoid pressure infiltration at those points. A similar im- pregnated joint filler was placed between the vertical entrance trunk end steel cuver plate to similarly avoid prossure tnfiltration at thee points. In any case, the internal pressures were of magnitudes such that the structural behavior was probably not appreciably affected. To repeat, the endwalls and entrances were not intended to be satisfactory for an actual shelter. A final shelter design could certainly provide adequate sealing to prevent harmf’! internal pressures. 4.2.3. Missiles and Dust. In all three concrete conduiis in which missile traps were installed, no evidence of a missile was observed. In all three concrete conduits in which a dust investiga- tion was made, debris varying from microscopic particles of dust to discrete pieces of mortar, wood, and small aggregates of dirt were observed. According to Reference 38, It is belleved that under the conditions of shelter exposure occupants of the conduit shelters would have suf- fered no harm. The dust might have been annoying to personnel and might have interfered with certain operations. 4.3 NUCLEAR RADIATION SHIELDING EFFECTIVENESS Since the maximum nuclear radiation dose that may be measured with 2 film pack is 70,000 r, no experimental method was availabl: for direct measurement of the high dose received at the {ree-field stations close to ground zeco, The free-field gamma measurements listed in Table C.1 of Appendix C were obtained by extrapolation from data obtained for Project 2.4. It is recognized that the validity of the tinvar extrapolation tu close ranges is open to questioa but no other procedure presented itself. Free-field neutron dosimeter readings 2re also listed ia Table C.1, The maximum dose inside any conduit was received in 3.2f having 5 feet of earth cover. The gamma dose was 7.7r and neutron doze <10 rep. According to Reference 24 the probability is that this dose would produce no significant medical effects on human beings. Thus, it is evident that all conduits provided adequate protection against nuclear radiation under the test conditions. Chapter 5 CONCLUSIONS and RECOMMENDATIONS 5.3 CONCLUSIONS MEER, Cae met % ey a bry ED se Based on the field test results, it 1s concluded that all types of conduits lesteu, .Trugated Be ; Zh steet circular, corrugated steel cattle-pass, and concrete curcular, will provide adequate ie Class 1 (100-psi overpressure and comparable radiations) protection for the same condittons (loading, soil, dimensions, cle.) as those of thts lest. In addition, for the particular conditions of (hus test and within (he accuracy ot the over- pressure metsurements, io was observed that: a < cst o oe (1) The corruyated steel cattle-pass conduit with 7.5 feet of carth cover withstvod a peak ve overpressure of 149 psi. ats (2) The corruated steel cattle-pass conduit with 5 feet of earth cover withstood a peak ae overpressure of 126 psi. att (3) The corrugated steel circular conduit with 7.5 fect of earth cover withstood a peak ry overpressure of $26 psi. es , (4) The precast “onerete circular conduut with 7.5 feet of earth cover withstood a peak ft overpressure of 126 pst. (5) Al! conduits tested provided adequate protection against nuclear radiation. Present knowledge does not justify making more general conclusions. ie 5.2 RECOMMENDATIONS ot Me If future tests are made on similar structures it is recommended that the structures be Ki instrumented to obtain the following data; te (1) Soil pressure versus time at the soil-structure interface at several points around the , structure periphery. (2) Sotl pressure versus time at points in the soil cover between the earth surface and BS Fe the structure, it (3) The relative motion of the structure with respect to an undisturbed point in the earth Is as a function of time. i (4) The change in shape of the structure as a funetion of time. M (5) Air pressure versus lime inside the structure. @ “ (6) ALL time records should have a common zero reference. ny There is a need for further study into the nature of shock propuyation through soll, Many ‘ Mi questions are ts yet unanswered regarding the altenuation, reflection, and refraction of shock i energy; regarding the partition of energy when a shock wave meets an air-soll boundary, a 2 iy water-soul boundary, an unsaturated soil-saturated soll boundary, or a structure-soil bound- * 2 ary; and regarding similitude. It 1s recommended that these questions be thoroughly studied, “. ie both analytically and experimentally, if we are to obtain a rational solution to the underground ’ > structure problem. | h ; Wy cy a 'y 43 I @ hy eae aA a2. © e ® ; ® e @ Ad ® e e @ @ 6 ® = “ : Mag ag % es eS wee ae Cres Appendix A CONSTRUCTION 4.1) RESPONSIBILITIES Construction for this project was accomplished by means of a cost-plus-fee contract administered by the Armed Forces Special Weapons Project and the Atomic Eneryy Comaussion. bxcavation survey for thas project comarenced at Frenchman Flat of the Nevada ‘Test Site on 5 March 1997, actual construe- lion started on UL March 1957, backfill commenced on 23 April 1957, and had been completed on the {inal structure on 4 June 1957. Construction of all structures was performed by Reynolds Electric and Engineering Company (REECOQ) with Holmes and Narver (HG@N) serving 2s general construction tnspec- tor. The Bureau of Yards and Docks project oificer served as technical inspector at the site in connec- tion with critical construction details. A soil-survey program wax conducted by the Waterways bxperiment Station (Projuct 3.8). A.2. CONSTRUCTION DETAILS Schematic drawings of all conduits are included in Chapter 2 of the principal text. A detail drawing of the neutron-threshold-evice recovery tube is in- cluded In Figure A.t. In ordee to provide additional detsils of procedures uxed for construction of the tust structures, constructlun photographs arc includ- ul as Figures A.2 through A.5. Selected portioas of the construction spucific ittons are gtvon on Page 45. Aw} SOIL SURVEY PROGRAM A.3.0 Soul Data, The xoil survey program (proj- ect tA) consisted of: (1) compaction control (sand tensity atethod) during backfill, (2) record samples, Ch) soil teats in WES Evborutorien, (4) soil texte at NCEL, amd (4) determination ol water content of back- hil before shot. Specifications for backfill ary iiclud- addin Appondix A 2. Slove analysia, ¢hiusification, and compaction text data of the sail asad for buck fl are included tn Fig- wie A.6. Density and moisture content measurements utilized for compaction contro! Curing backfilling oper- ations are included tn ‘Table A.1. Triaxial shear tests were performed by NCEL on one sample each from fill over conduits 3.2f und 3.21. The tests were performed, using 2.8-inch diameter specimens, on -Yeinch fraction (93.8 percent of total and 94 percent of total tur 3.2f amt 8.21, respectively); the rate of strain was 0.1 in/min. The results are given ut Table A.2. The results of chemical and spectrographic analyses which have been performed at NCEL, and the density and moisture-content measurements taken at the site (Projevt 3.8) are included in Tat’: A.3. Additional data on the natural soil at Frenchmen Flat and on the gravelly silty sand used for backfill is includea in teference 25. A.3.2 Excavation and Backfill Operations. The earth was excavated so that the iust conduit sections would be completely surrounded by a gravelly-silty - sand backfill. The earth excavation lines are shown in Figures 2.6, 2.11, and 2.25. Compaction of back- fill for thie project was performed in a manner as nearly virailar to standard construction practices as practicxble. The entire fill was coiapleted in order to simulate an actual installation, whereby natural consolitation would compact the meterial within a pertod of several months. The backfill material was cxcavated from a preselected area to an approximats depth of 5 feet. Ths sof] was rumoved from the pit using self-propelled scrapers, together with loading pusher Cats, hauled to the site of backfilling in the scrapers, and stockpiluct at cach structure excavation. During the digging of the backfilling material, water trucks kept the surface of the soil well saturated. An offort was made to kecp cach scraper load as uniform 28 possible by scouping sorl at angles so that material from the surface, 28 well :.s material from a 5-foot depth was Included in each scraper load. The backfill stovkpilos were not processed further oxcept for wetting the surface of each stockpile with a wator truck prior to (he start of backfilling opara- tions each day to prevent excessive surface drying. ty placing the backfill material ia G-to-8 inch ite with a clamebell, the utilizing cumpaction methods tleseribed te thy next paragraph, compaction require- ments (90-percent maximum density at optimum mols- ture content) were xatixfied. Up to a point approximately 6 feet above the Lase of the conduits, the 6-:nch pneumatic tampers shown in Figure A.7 were uscd in a pattern .llustrated in Figure A.8. From the 6-foot level to a leval 3 feet above each condust section, gasoline-driven vibrating rollers were usec. Frur pasees over each area pro- vided ample compaction effort. The operation of the | oe, 4 TN, >, ne wy, Maa Ts * iy xi Be dkig ee de a em. oe sed Barthes Barty fees Uxeg haath sant fell asterisd wie Horii ste a Dy the Coove sresent te the ceatractor tes thon Pertation ty hin Chane bar ecow yds be ited within dian es of the site of the werk Borrow pits shall be yeraded it tate todrun property se that the extating surface train - age will he anaintuined Any surplus earth not requin -d fin Ohi or bac htthing shall be removed and deposi d within 2000 feet of th site of the work an diructed. jot! pita shail be graded ana maaper to dram properfy sa that the existing surlace deamage ail be maintained. PAs ateans shall be aerted to the contours, chin n- pions wing deplts tadic ited on pecesnury Es awattate eared bebe the ceptlis abetted without specie dices treme stad be cebifed to the pooped gaude with Chocougtly compacted suitable Hl, excep that en excavations for Coat days, on tor buted com rele members the cancrete shalt in extonded to tbe bettas ot the cxcsvtiion, lb titan werk of this nature stall be done tt oo wokfitromed cost to thes Cocovernarsesersat NED ares uwsteenenzs cnty Dee- rapsabe: Foy crseattin ad tanchings, eseepl (hot the List six mehes of carth nd the Croumiang of the excavetions shall be dove by hind ina Garecloll avegrate manne jo the exact grades and slopes tlie tetas directed bxtreme care shall be exert sod for Steg the Dbollotes of excavations fer cir ales ated arreg- tibet Sthapersd crtcobern ss tee thee Contents pocorn dy to provick souttoveus oft bears far the members. Prior to back - LM operations, albdubras, nich, and other loose silt shall be removed fram the excavations (kuekbld shall be tuken trom sand and gravel pts (selee- tel by the progect atfieer) excavated untlormlty toa depth of feet set shall be ptaced in bined lifts an a manner Chat wild not cused segregation af (be bas AGL matarial. AUD bac Wiebd and CP sind be compacted to at least 90 per Cont nasi dents at optim imotsture content by Media of poanMtte an other mechanical compaction equip: wend ME back) placed within 2 feet of tho structure sted be tree trom rocks, bogklers, and clods larger than Danehes at the groatest diension, .tob vugetable matter ambother debris, olbyewine the backlit! material may be und sobbed trom the pat The back All shall be phacet th allernate Layers trom beth andes ot the structures main Gani an newly an pre table a uniform height of bch Subd at BE tds, tee ee eas shoul the bac. filt ae ane edike be cortied more then fo onches higher thie on the opposite sake Phe mnessture content amd aunty of the soil will be sheoCare rested bry Frengere to Ub et on chetermingsd (hat mode Crores atin be tebbeed to the exiting stock pélest tater, the tnethols goregeapedd to be. decd by the contractor for ahd Hg, Ube wantern, teeetng, ole bead dee appreve cl by the gery amtieotte Pete too the tet ob Pate Weddings open atienns te anv oase, all prowussang requried Go obtain the spocifited wailed content shah be a compluashed before the mater til in Paced iround or over thy structures Th earth (el shall he maintained withia 0 tolerance of plus or micus Vy of a foot on the cover Prior to backfilling, the con= tractor shall ascertain that end bulkheads are plumb and are oot separated from the condult sections. Backfilling shall not be started unui the contractor is cartain that one t‘urted a day-to-day sequence of backfilling opsrations can be effected baith moving equipment may be uscd according to stan- lard practiee, cxeeszt that to huavy equipment will be ver- Tatler lo operate over the crawn of the structures unt | at least. fteetot earth aise been compa ted over the top of In no couse Should equipment used for com the structures = EXCERPTS from CC-ISTRUCTION SPECIFICATIONS poction exceed swefice prossure of [bp Preunnitec thre! tae s may he aed tos catipdte ting che dae REDD an mudiately adpicent te the surtaces at the structuras Convrele Constias tion. Concevte may be reads mixed AU Com tote shall be Claas Lt eluee pap. Setting wiscetlum ous material When practicable, al sochorn atin bolts sa connection with conerete shall be placed and xoctred in poaition wavs the concrete i placed Anchors nd anchor bolts still be plumbed carctully and set tecunately and statl be beld ca position eigidly to pre vent disphicemeat duriyg Uhe plas ing of the concrete Conmtete pipe unheated ts. coaiuit) shall be 3.000 psa stindant strength somforced .oucrete sewer pipe confor in tz to AS TAR Specttication (75 05, the pipe ahall hive foguceand poor semis. Phe curerete pipe shall be lant eos solid bat of earth, all yout aball be bullenal with ut 1 te 3 coment mterter prive te woembls of sectiata. Atler assembly, roms stall fe Cllad to (he level of the adfccent surfaces of the pips. Prefabricated Structures. Phe ingress tunnel and pipe whall be of co rugaiedl steel cubert pipe coaformuyg to the appitcable vequrremen's for Tye t, Clase 2 of Federal Seetfication QQ-C Sea, exeeqd that zine -coating will not fe required Metal stall weigh aot less than 6.87) pel Qiominal 4-gaze) he face corcug ting Openings shall be cut accurately and fitted noatly Cornigatoe culvert ype shall be ot metal weighing not Je «x than $5 620 psf before corrugatiy, (nominal 10- eae erm anne ate tenaetn ersea - ~ « wot re ~ Seen “e ~-~ -— PL ae ae eee ee ee ne ne Gia Pe grees —~——— ee 47 J e ¥ 4 ek cams | 4 w- Nos? , ce * SR ail Be ee See ee ate "Roce EB £3 =e iY . * oa “3 ‘ ae sf ‘ . oe ohn, : ; - ie 2 4 iy Ff ’ s = at ‘ « e . a 1 t “8 n . 5 ro aw Ss a { e ‘ ‘ 4 . . it , ” ' . ; 2 aeye * : f ‘ . ¢ . ¥ a : By b = S ! ’ 7 ‘ i t mod t od . Figure A.3) Lowering ausombled « attle -piss conduit into excavatio 1. * ee * ae se ey, ey ¥ = a Re = soi ae. * SO ERT Ce RAE A ee eR ee } pO Te FE J x, Pee Lead etn +o Ye somws 5. Kf w\ Figure A.5 24,000-pound ce crote conduit section being positianad. 49 eLLs gt | Po ered Ld rere “Ag ULB STANDARD SEVE S:ZE 4NnOK Grovoliy-Sity-Sond nts Figure A.6 Soi} survey compaction test report. i mE aie i a IVa get a2 N3/es> “ALONIO ABO WATER CONTENT, PEACENT OF DRY WEIGHT Project 32 Compoction Curve For ws NG RRO gr cree te meee reece of ~~ t . pue Figure A.7 Tampimy backf)? with pneumahe tamper. © 1° Leteret Movement fw Eech Siow cf Tamger -) | F rst Oirection =} eg Ps = 1 Fare A Cronpacting backHt woth posoline leven vila ating colker compactor is indicated in Figure A.9. from a level 3 feet above each conduit to the level of the original sur‘ace a D-8 Cat crawler tractor (bearing pressures approximately 10 psi} was used for compsction by making four passes over each are2 Appendix 8 STRUCTURE [MSTRUMENTATION B.k DEFLECTION CAGES Scratch-type deflection gages, utiiized to deter- mine miaximun ant ressdual deflections were fabri- cated and installed by NCEL. The scratch guge (Mo! eb P-3.2) tHustrated in Figures B.2 an! 8.2 consister of a serthing atssembiy, (wo scratch plates, and atte t- ing hardware. ‘The seribing assembly was attached to the wp of the condutt sections by bolts. The scratch yiawo were 16-guge aluminum sheets, 12 by 13 inches, with 44-inch flanges turned on their sides to act as stiffeners. The scretch plates were coated with con- ventional machinist's bluing compound, thus, the scratches showed as aluminum colored. The scratc! plates were attuched with machine screws to oppocite flangus of a '4-inch steel channel, 10 by 12 inches; 7 this in turn was welded to « stee? tripod having 1'4- {ach pipe legs. The complute assembly 18 shown !n Figure B.3. < Full-scale scratch gag records are inclined as Figures B.12 through 15.15. [t ts considered that the Mode! P-3.2 seratch deflection gage performed salis- factorily except for measurements in Condults 3.2a, 3.2¢, md 3.2d. In the-e three cases the scribing stylus jumped from the scratch plate before record- tag a maximum dynam deflection. The shock im- purted to the tripod legs evidently caused the scratch pla v to move away from the scribe. A spring tensio: of 16 pounds had begun used; however, by increasing the spring tension, the pressure on the plate could be Incroansd thereby avoiding a future similar situation. B2 SELF-RECORDING PRESSURE VERSUS TIME (Pk) GAGES INSTALLED BY BRL, PROJECT 3.7. The recording mechintan for the progsure-timo Kats wae enclosed ina leavy airtight case, the top of whieh refed asi balite plite Holos ta the bafflo plate vtlowad (ntthation im) promsure intake. Ths sensing o'ument was basically a chamber forined by welding toxethar two diaphragnis at their edgey, ouch of which was impressed with a series cf connec tive corrugations. A stylus, consisting of an osmiuni~ Upped p..onograph needic mounted on a spring arm, was attached to the element. When pressure was transmitted inside the :lement, the element expanded. Thi. expension, which is proportional to the amount of gressuve, was scra’ched on a stlvered glass disk . by tne stylus The glass disk was mounied on a turn table and was driven by a esrefally governea motor in onler to record the scratch of the stylus versit Gime Calfbration of the pressure capstlus was perfornied by the manufacturer The enltbrations wore plotted using 2 Leeds-Northrup X-V recorder. The output ot a Statham strat -yupe-t\ pe pressuce trangducer was fed through cmplihers to the pen (X-axis) of thy recorder. Capsule deflection was measured by a micrometer head equipped with a mall detector und servo system operating a slide-wire potentiometer which, In turn, controlled the chart drive (or Y-axts). The resulting presentation yuve a plot of capsule de- flection as a function of applied pressure. ‘The pp gage is shown in Figure B.4. Actual instal- lation of the gauge is shown it concrete base for over- pressure measurements in Figure 8.5. The seif-recording measurements observed un the ground surface arv included in Table B. 1. Phe values shown in Table 1.1 are used in ‘Table 3.1. In all cuses the overpreasures are within 10 por- cent of the preliminary composite overpressure curve for Shot Priswilla. B.3 PEAK PRESSURE GAGES (INSTALLED BY BRL PROJECT 3.7) The poak-pressure gage utilized 2 pressive capsuls Uke that ust in the pressure-ime gage; however, in this gage. the recording blank was held sationary. The recording blank, a gilvered glans rectangle, was put In place under the capaule xtylus. The stylus, whon activated by pressure. reported the maximum Positive and negath, «deflections of the presasur cap-~- sule, This capsule wove calibrated by the manufacturer atmilarly to the py page Paygure 16 sbowr Che anatial- fatten of a poak presets gine an Che acco om of the timber bulkbased. ‘The peuk internal prossurs measurements ob- served are shown in Mable 8.2. The ruliebility uf the peax pressure values is questionable and it is concludc- ed that £ su.f-recording pressure-time gege would have provided a more accuc.ite and reliable record. B.4 DYNAMIC ACCELEROMETERS (INSTALLED BY BRL PROJECT 3.7) .4.1 Electronic Accelerometers. Electrontic- Pad Inde thon dynamiceacceleromet r-versus-time mea dremunts om gryaronaoudad LON WLOB~o/1 UNpUor spysuy PIT [wisuy Ve uoprayap yores.g gZ'g ounSyy RW A3ddvi 114969 OV INN BI “Aiqurosse Zutqy1oe eFeF uonoseyeg 1G enka 3 e F e § @ a ” -. a ot In| r : 3 x a % or RETIN Pa Ge ee OS ay ey Deas . wy Lae ee Be aes ¥ ay ™ ahvie, ae # wo FRET t Zi pe © ~ 4 fe wets ye og ¥ . i 1 *h ann 7 “SETS ~ a“ somes Nn e ‘ a ‘ - - s € : . ’ toy, - 1 2 ATAIONGOUdAY* LON! , ‘Bay podyz2 om paier afprg uty ewured pue Ja9uysor nRet vut~asessacdt But 19398-1196 9g end TVILWI RON —-uOFeTpersuy SBeP yoiesos peo (r ¢ gq ssnkyy { we” oe . . NES I SLOSS A aR rh Mi aeenel NARESH: «PRIS RRS NRO TRIE BE he ATES be all H + uy yg . 3 : : ” Figure B.5 So!f-recording pressure-Ume gage mounted in voncrete base. Figure 8.6 Pouk pressure gage installed on Gimber bulkhuad al wevess-end of conduit. w. 2 > - were made with Witncko Typo SAAT accelarometer . ‘The sersing clement consisted of an armature bond edb at its center tu the vertex of a Vo shaped spring Member and held in close proxamity to an E-coil Av weight was attiched to une end of the armature so that un aceelucation ina direction normal to the art-- ature caused it lo rotate about the vertex of the spring. The E-coil consteted of two windings wound on the extreme legs of an E-xha ud magnetic core As the arniuture rotated, it decreased the reluctince of th Magnetic path composed of the armature, the cente leg, and one extreme leg of the E, and increased th teluctance of the other, similar path. ‘The electron - accelerometers were given static calibration on a apn table accelerometer before their installation (Figure £8 7). Phe spin ible was a disk which was 1otated ata apecd determined uccurately by an electronic tachor - cer ‘he accelerometer was mounted on the dink with its sensitive direction paraliel to the sadius of the disk. Connections to the recorder cabls were math: through slip rings. An accurate knowledge of the distance of the accelerometer sensing elemest from the center of the disk and the rotational velocity of the dink were used to [treat the radial acceleration produced in the sensing elemount. The installation af the gaye in the concrete conduit 13 shown in Figure 8.8 (left). ‘The results of the electronic dynamic acceloration mennuroments of the conduits are shown in ‘Table 8.3. B.4.2 Salf-Recording Accelerometers. The soff- recording ucculeromuter utilized an element similar to that used in the poik wcolerometer. To obtain acceleration versus time, the recording disk was rotated. The installation of ths gage is shown in Figure 8.8 (right). One xulf-recording accelerometer had been instal- Jed in 3.2] in Hou of 2 peak accelerometer. The rea !- ing (- 10g negallve) {* questionable. Because the cluctronie records were considered good and tho se - recording and peak viluus (Section 8.5) were some- wha’ queationablo, the eluctronic values have been Considered more valtd and consequently havs buen ulllazed for discussion, BS PERAK ACCELEROMETERS (INSTALLED BY BRE PROVECT 3 7) The pouk accelurumetec was basically ibe same as the peak-pronsure gage (Section B 3). Instead of 4 Prcenburce-senwiNg Capsule, an accelerometer ele- ment wus utilized. The element consisted of a cantt- lever beam with 4 weight attached to its free end. A spring arm attached to the weight held a stylus which scratched a record on the recordirg blank when the elament was activatec. The cantilever beam was sh iped to prevent oscillations in any direction oxcept th $ destred. The accelerometer vlements wore calibrated by clamping thom tna support simifar to the one fa the Kage. Thee support was then placed on a calibrated drop table Co be subjected to tranment seceleration The drop table constated of a heavy nwtal plate whien wis rateed to a pruddsterminad boight and then allowed to fall froaly. The fall wax terminated by 2 box of sand into which the plate falls fat. ‘The accelerations produced when the plate is stopped were accurately reproducible and by means of a standard acculerom eter, have been cultted to the height from which the plite was celeused A peak accelerometor, attached to the bottom of the concrete cuaduit section, in shown in Figure 8.0. Results of the peak sevelorometer readings ob- served ary xnown in fable R4. ft has been comeluded thet the electronn dynamic tcculerameter would have provided 2 more valu measurement B.8 MISSILE TRAPS ANSTALLED BY LOVELACE @OUNDATION PRCSECT 33.2) {easmuch as low-velocity sussiles secondary to large-scale explosions have boon 2 significant cause of casualtios. misxils trapy were tastalled in all the concrete comlults of this proyert to determine (1) if concrets conduits ware a xourve of missiles and (2) to examine the ballistic properties of low-velocity mixsilos which might be produced by compression inilure of the concrete or by spalling of concrete as the result of a tension crack. Styrofoam wax used for the missile traps. The relatively low shu:r properties of the material and its nom-fibrous structure result in localisation of compressive deformations. Styrofoam's resistsnce to deformation is low enough vo that relatively slow missiles penetrate sufficicotly to be measured accur- ately. The missile trap consintod of 2-inch cheets of styro- foars 6 inches by 36 inches, covered wita aluminum foil, and attached to the inturior surface of the con- crete with asphaltic coment ia 2 manner ladicated in Figure 8.10. Acklitional data on missiles secondary to nuclear blast are includod in Ruforence 9. In all three concrete comluts in which minuile traps wore installed, 3.290, 3.2), amd 3.21, ne evidence of 3 mixnsle had been cbacrved. [tis concluded that for the magnitude of duformation expyriunced ly the concreto conduit sections of the projoct a minails hazard docx not exist. B.7 DUST COLLECTORS (PROJECT $3.5, REFEH- ENCE 8) Two somewhat nimilar types of dust collectors were utilized. The first, which was taped to the floor of each shelter, consisted of sa ordinary glass micro- scopic slide, one inch of which was covered with trans- parent sticky tape, sticky side up. The second wns a proses OFquUosony 9g> $0'9706 we'¢ Pr0der Siquoojeend ot> b0°9TO8 me Prooer siqeuuoneend s> 302108 fers P10992 O[quUO;sONy $> 20°St0s a's p10d02 stqevonsend $> 90'9t06 2e'¢ prooes siquao;send g> tO°HT06 we Pi0dses Siqetonsond g> TO'LT06 eet Pl1o0oe2 03 pojsay eFeH _— To'stas pe's Pr0d02 BqQuTONFONyd g> f0'9T06 33's ps0res arquuotsond Q- ¥O'9t06 q2's pugoe2 o(qeuongsond 9> 10'9106 "zc 2 UONBIaTBN9Y axLeutr9y oanefoy uoyeig ermon.zig SONIGV3Y HALINOUITZOOV Nvad 20 SLTNSAN HE FIGVL “POPJODOY ION « at 90'9T06 me's ot CO'LTOS W's ot £0°9T06 xe oe 20'°LT06 fers St ZO'St06 q's o's 90°9T06 Fe's o's 20°9T06 3e°8 os T0°L706 o's ore tO'eT06 P2'6 02 $0'°9106 3o°€ e ¥O'9T06 q2'€ “ae TO'9T06 8z's ied @INGSIIG uonwns SINSMZUYNSV3AN AUNSSZUd~-TVNUZINI Bvad Bhat aanjonaig jtusowwy yeog es FISvL ° pare ATR nag eee ae ee eee procey on 8° ——(O'GT> tO'LTOS ws procey poop $h0°o os $0°9T06 R's proosy poop ¢40°0 03 209106 y's prose poop 020°0 oe 1O'STOS wc oe2 3 sysewey wopeing enter WO" BONTIS SIMON SINZIMZUNSVIN NOLLVUIISIOV OAAVNAG SINOULOSTS £0 SLINSAY Cd TIGVL “S'S afOrg Qoqquintd jo wed ¥ 0q O73 Peropisu0s sem (cy Soworezey) Qe'e pee Iz-¢ TI0q O1 WWOCR[pE ‘FET CYL» 300d 1980 1210 09 380 L106 elt poop sce'o 91-0 oot $0°9106 4-22's pooh 902°0 soto 921 $0 9106 P-o2 § poop 2e2°0 — et (v v106 REE oes 308 13d ae OR NIG tt 2, proo0y topeaing oUrhT @insseid190Q Ayend _sanieod saat SZOVSUAS aNnoOUD NO G3AU3S8O SLINSMGZ! “SVaH 30° ONIGUOORY-413S 8 F1AVL : Sloe Tee aig ba es ee —— Bs ar RS Se een ae Sem Figure B.7 Calibrat oa of eluctroaic acceleronwter. * e Figure 8.4 Electronic ace ulerometer (lett) und solf- recording rs ae accolerome’er (right) Installed In coneretk Conduit 21 + “ ‘ . mae ores. . Regen ks oa % 7 *. Ded “sa ire BS aS Se ne Ate, tor installed on recording peek accelet ome’ if- Se igure B.9 F hottom of concrete conduit. “= 810 Stvrofoam miss:'e trap inz.us concrete conduit Pa wee . WHER §— 014901280 1ONB/30y “UNPUOS BOIIVO0S spjsUy polfersus SIOJDeqIC9 Yon II-y eundrg eh te Se wwe * os sticky-tray fallout collector, to provide rigidity, at Vg-tnch thick plate of zalvanized sheet metal wy, by 10%, inches) was employed cn top of which a tr: as- pstrent, but sticky, paper wap lixed with maski ig tape. papers was removed and the uncovered side of the collector waa marked C for control. Upos Button- up of the structure prior to the tes., (D— 3 days) the other protective paper was removed, thus oxpos ing the other side of the collector marked E for expurt- ment Che two typos of dust collectors which ware . raxtalle bin Conduits t.2e, 3.2), amt 3.2) aro shown in Figure Is.t! ae xg Pent 3f t 4 wr Rear Rees 32e 3.2% ° ' tIngnes Figure B.14 Deflection records, Conduits 3.3g, 3.28, and 3.2}. Pigure B.18 Deflection records, Conduite 3.2%, 3.23, ~ Recovery of trays am! slidey was accomplished a upon uitial poxtshot cutry of the structure (D + 8). ce The top af the microscepie shies were covered with ee 2 pleve of transparer’ scotch tape, and the fallout : “ mn oes a i oat =f ee Presa ie ford . ie ; . oe ve 32) .13.2m. ures served to protect earh of the ders ollectors from coetamination afler removal irct he veveral , structures. After recovery, the two opposing pheets of the transparent, sticky puper were str‘pped from the fallout trays. The sticky puper was successful in trapping debris varying (rum microscopte particles of duxt to dincrets pieces of mortar, wood and small ‘The top of the sticky tray (8 by 9 inchen} was protect trays, after being pricd looses from the ficor, were Ee od by two ructangular pieces of paper which ordinarliy placed face to face, bare being takes to oppose the - are strippod off just beforu exposure to the collector. contro! -lide of one collector to the csatrol side of ‘i Upon [nstallation of gach plate, one of the protective the other taken from the same shelter. These meas- ees ae = ad L cs a Feont Front Front Rear Reey Reer . : 3.2 32) 32m -— ° ' oor [ rs lwehae ‘ y aggregates of dirt. A few slivera of woo muasured % inch wide. (It shoul be acted that the wood bulk- heads on the structurun of this project are not a part of the actual shelter deaign but have been used as an economical method to provide cloeure to the conduits for the purpose of this test). Each microscopic slides was comaminated with dirt and will be usable for subsequent microscopic studius. The data obtained will te subjected to leboratory analysis by Project 33.5, using microscopic, photo- graphle, an’ chemical methods. As much us possible of the trapped debris will be tdantified. It ts antics- pated that dust collucted preshot from the bottom of thy comiuits will bu most helpful tn anding ths obser- vatioas calculated to establish the origin of postshot mitertal collected on thé experimental side of the fallout trays. : Appendix C MUCLEAR RADIATION INSTRUMENTA TION Prepared ‘o> Prcject 2.4, Radiological Division, U.S. Army Chemical “/arfare Laboratories; Qobert C. Tompiins, Project Officer C.1 BACKGROUND AND ‘THEORY To its prior to Operat'on Teupot have xhown thut below grade sheiters give 75 percent bette: gamma shielding than thone shelters which ure partially abova grade (Refer nce 26). Operation Teapot data i!lustrat- ad t: at completely bolow-grude shelters with fou - feet of radtal earth cover gave an tam ‘e-to-out.ide gamma dows retio, to be desiynated herein as 2 gamma trans- mixston (actor, 2s low as t 2 by 1074 asd a neutron transmission factor of 1.5 by 107” for ths high enerry neutron flux which would ‘oe detected by sulfur-threshold detectors (Rufevence 27). Oetector ststions esarer to the entranceways of the structures In. -xted much high- er transmission factors, and therefore received high- er radiation Cosagus. ‘the shelturs to be instrumented for radiation meas- trements at Operation Plumbbob were al! underground. vor this rn ton, Uw Operation Tezpot results in below- node structurus UK-3.b., UK-i.8b, UK~? .c, and OX-3.7 worse paeticularly useful in predicting: expecte | shielding by the shelora at Opwration Plumbbed (Raf- erence 27). ‘I! se results wero augmented hy empire teal relations for nuutron and gamma radios pass- +g through hollow cylinde, sas given la thy “Ruactor Shuelding Qualyn Munual” for evalua the uffect of vaclous opunings and baffles (Reference 28). Im the causa (the Op ‘ration rlumbbob 3.2 strectures, ‘10 predictions Indicated that they should provide consid- crably greater radiation pr tsction than thet provided by the below-grade Oporation ‘Tuapot structures, since none of thom vould have any entrance ways or ventila- ston system openings ul shot timo. Morcovor, tr levels of protection should he about equal throughout the main portions uf Uso test nuction. C.2 DESCRIPTION OF INSTRUMENTATION C.2.1 Gamma Film Packets. Gamma dose was measured with the National Bureau of SXandards— Evans Signal Laboratory (NBS-ESL) film packets (Ref- erences 29, 30, and 31) [n Ube oxposure rangs from 1 t $0,000 Fr ond In the unergy range from 115 kev to 10 Mav the accuracy of the dosimeter is considered to be within s 20 percent. The net photographic re- sponse ts expected to bu approx’mately exergy inde- pandent. This is achieved by modifying the bare- cmulsion energy, cesponse, which has peaks naar the K-uhell paotogloctric xbsorption edges, absorber aad brown. 4, by placing the entire emulsion tn 2 8.25- mm-thick ook:lite case covered with 1.07 mm of tia and 0.3 mm of ‘sacl and surroundea by a '4,-inch lead atrip over the open es‘:es. The entire srrangement is plarws ih a plastic cignrette cuse. Although the angular degandence of the gamma Rim prcket wh. it is exposed to high esargy redia- tion is negligible, for lower energies it is important. An inturpeotation of the results obtained by Erlich (Reference 30) indicates that, for radiation jvotrop= ically tasident un the packet, the dose valus is sbout 5.8 parcant lowor for 1.2-Mev radiation than that obtalnod by un instrument having eo angular ““spacu- once, owt 32 percent low for 0.26-Mav t dination, and nbuug 45 percent low for 0.11-Mev radiation. Al- though tha film packot~ may show only 4 20 percoat error tn nora) radiation fields, some consideration shou’ be given to the fuci thet ina relusvely isctrople and degraded one: cy fiukt, such as might exist ia structure’. with maay fevt of earth cover, the flim peckats ram, indicut: le values. C.2 2 Chemicu Dosir-eters. The chemicas dociz- oters uiized for instrumunting the structures were supplied by the Unite ' Staws Air Force Soboo! of Aviation Msdicies (8AM). The SAM . be. nical dosimeters lactude twe main typos of chemical Kye: sme. Onu system is bydrogen ree, while ths cther xyxtem ‘oe a Aigh hydrogen content. The Istter e, stem Is osseatially water- oqu.valent in its response. The Ngh-hydrog7n-costest dusimeters respond to all the garsma rays, fast nev- trons, and thermal nvutrons; whereas the hydrogen- frec dosizasters respond only to the coexistent mamma rays ond thermal neutrons (Refcrenoa 31). Both sye- tema ars based on the xame princ pis: acid formed {rom the radintton of a chlorinated hydrovarbon je a linear function of radiation dowe throughout # brows! range (25 to 1v0,000 r) ‘yew References 32, 32, 33 aad 34). Neutron culbration of these systems was made by G. S Hurstand P ob Harris (Relerem e J5) The hydrogen-fige dosimeters utilized were fur- nished by SAM to the fallowing prepared ranges. 0.3 w &, 2 to 20, 5 to 200, 100 to 500, 400 to 2,000, 1,600 to 3,000, and 2,000 to 18,000 rep. The high-hydrouge dosimeters utilized were fur ished in the following prepared ranges: 10 to 200, 50 to 500, and 130 to 1,000 rep. All of the dosimeters if uxposed within th ir pre- pared ranges were evaluated spectrophotome rically or visually by observation of the color change 3 in the (indicator dye from red (pi! 6.0 ur above) to yellow (pH 5 6 or below). Sines these color changes are a function of the dose, exposure doses wure cKtimated by color vomparison with irradiated controls. The atvount of acid formed, hence the amount of absorhe | dove, in over-exposed dosimeters (pl 5.6 or below wis evaluated by titration with standardized 0.001 N so hium hydroxide. Division of the amount of acid produced in an unknown exposure by the calibration data for (he sennitivily of the system to Co® gammo radtation (namely the umount of ectd produced per milliliter of chlorinated hydrocarbons for esch reent) 30 absorbed) yielded the gamma dowe iy ronigens. The measurement of the neutron dose with the hiph- hydrogen-contunt dosimeter was accomplished by evaluation of the amount of stabls actd produced in a mixed radiation field by one of che above techniques. Since the water-equivalent, high-hydrogen-content dosh “ter is X- and ganuna-ray energy-dependent and has 1 known neutron response, the total acid pr: - duction cen be considored as a combined function of the neutron and gamma radiations. Subtraction of tl > wamima produced acids as measured by the fast neu! ‘on insensitive cu wmical dosimeter systems (Reference 32) left a given quantity .. -‘ nroducod by the neu- trons. Division of thts nuutroy~ps. ‘ced acid by the acdy .por cep yielibul a neutron dows |: terms of rep. Samma meusuremonts (n the poer- ve of neutru: + wero nccompliabad by using the hyacogen-frue dost: cters. Since all chemical dosim ters are sensitive to thurmal neutrons the Ux+mal neutron dose was calculated indepemlently from cazimlum-gold differ- ence nuusurements. The data wore then correctod by subtract'on of 6.7 roentgen ecuivalents per thermal neutron rep (Reference 54). C 2.3 Neutron Tn.eshold Devices. A complete description of the neutron system used for instru- menting the structures can be found In Reference 12. Thermal! and epithermul neutron flux was measured with gold foils by the cadmium difference method. This technique )lelda the flux of neutrons below the vadmiun: cut aff of about 0.3 clectron-volt. Interned- late energy neutrons were measured with a sories of three boron-shielded {iss10a-threshol!-detectors; Pu? (.3 7 kev), Ap” (9.7 Mev), and U2? (01.5.4 v). Hi, h energy neutrons wore moasurad with sulfur de tet torn having on cffectave threanald of | Mev Th cadmium cutolf and the vatious energy thresholds are not clearly delined powutta For this roason neution fluxes in this repost will be adentified with detectors rather thin with energy ranges. The accuracy of these detectors is approximately 115 percent for dosus greater than 25 rep. Meas- urements are unreliable below 25 rep ami cannot be made below 5 rep. The detuctors were calibrated and read by Project 2.3. C.3 INSTRUMENTATION LAYOUT The objective of nuclear radiation instrumentation was to determine the effectiven sx of the Burted struc- tures for providing radiation protectian Accordingly. the structures were instrumented to mesaure the gemma and neutron dose that would by received at a nominal weight of three feet above the floor of thy atructure Stree the activilius produced im the th eshold de- wwetors are rulatively short-i:ved, siructare 3.2f, which was to be instrumunted with these detectors, was equipped with an aluniunum tube from which the thresbold devices could be withdrawn by meens of a cable system within a few minutes after shat time. The etructural details of the cable system are given in Appendix A. Since nose of the other dose detectioa systems require early recovery, thuir locations were coa- trolled only by the data that were desired. A film packs, a chemical dosimater, ead in some cases a thermal-seutron detector were installed in each of the structures. The detectors were taped to the tri- pod of the soratch-type deflection gages at a hoigit of three feet above the floor level of the structare. In this method of location vach datoctor was approni- mately at the ceatur of the 20-foot sectiena and at the center of the width of the structure. In order to calculnte irunsmission factors it was necessary to obtain free-fiuid realiegs. Neutron spoctra) data were obtained from thy line of stativas vt.ablished by Project 2.3 at 100-yard iatervals west from grount! xe-o = In additlor ~" * Josimeter antl film packot free-iield stations were locate! at tus ranges o: he structures tosted. C.4 RESULTS AND DISCUSSION Most of the froe-{luld NBN-"".". film peckets, which cannot measure dosuges greater thas 70,000 r, were overexposed, und the res¢ wure either neutron activated or lost in processing. Therefore, the free- field film packet Juta ob sined for Project 2 4 were nlotud as a function of _,stance and extrapolated to the rangos of interest (Reference! ) It is recog- nised that the validity of the linear extrapolation tu close raness is opun to question, but no other ,.0ce- dure presented itve!{ The doses rex from this curve are given in Table C } slong with the other free-field joxe muasure oth «Tro c homical dostmoter data wore obtained from a amouthed curve thro gh the TABLE C.1) FREE-FIFLD GAMMA AN > YEUTRON MEASUREMENTS Gamma Dose Neutron Dose si deebahd Flim Foil Method r rep 3.2 2.35 x 10° 1.92 108 3.2b,¢,d,¢,f 1.89 x 10° 1.62 « i0% 3.2g,h, J 135x 10° 1.24 . 10° 3.2k,1,m 1.02 x 108 7.65 > 104 ABLE C.2 GAMMA-SIIELDING CHARACTERISTICS OF PROJECT 3.2 STRUCTURES; SHOT PRISCILLA, FRENCUMAN FLAT Earth Dose, r Transmission Factor, Di/Do Structure Film Chemical Filn. Chemical Cover, ft Badgo Dosimeter Badge Dosimeter 3.28 7.8 0.2 .5 1 x107% = caesu § 3.2b 10.0 0.0 <5 <3x10 5 3.20 7.5 0.0 <5 <3x 1978 3.2d 1.5 0.0 <5 <3x 1075 3.26 2.5 0.0 <5 3x 1975 3.20 5.C 7.7 <5 3.8% 1078 te eet Pet Veiic ea Be es PENNS gine oe SEER “ee, —~ = € red ® ) ! . Boa bi =o Defense Nuclear Agency 6801 Telegraph Road Alexandria, Virginia 22310-3398 ERRATA 14 September 1995 Ab-89/ Wp MEMORANDUM TO DEFENSE TECHNICAL INFORMATION CENTER ATTN: OCD/Mr Bill Bush SUBJECT: Change of Distribution Statement The following documents have been downgraded to Unclassified and the distribution statement changed to Statement A: WT-1307, AD-311926 WT-1305, AD-361774 POR-2011, AD-352684 WT-1303, AD-339277 WT-1405, AD-611229 WT-1408, AD-344937 WT-1420, AD-B001855 WT-1417, AD-360872 WT-1423, AD-460283 WT-1348, AD-362108 WT-1422, AD-615737 WT-1349, AD-361977 WT-1225, AD-460282 WT-1340, AD-357964 WT-1437, AD-311158 WT-1404, AD-491310 WT-1421, AD-691406 WT-1304, AD~357971 454.20/8, If you have any questions, please call MS Ardith Jarrett, at 325-1034. FOR THE DIRECTOR: Ardith yg, JOSEPHINE WOOD Chief Technical Support JL. 20/8 Defense Nuciear Agency 6801 Telegraph Road Alexandna, Virginia 22310-3398 AD-691 442 14 September 1995 MEMORANDUM TO DEFENSE TECHNICAL INFORMATION CENTER SUBJECT: ATTN: OCD/Mr Bill Bush Change of Distribution Statement The following documents have been downgraded to Unclassified and the distribution statement changed to Statement A: WT-1307, AD-311926 POR-2011, AD-352684 WT-1405, WT-1420, WT-1423, WT-1422, WT-1225, WT-1437, WT-1404, WT-1421, WT-1304, If you have any questions, please call 329-1034, AD-611229 AD-B001855 AD- 460283 AD-615737 AD-460282 AD-311158 AD- 491310 AD-691406 AD-357971 FOR THE DIRECTOR: ERRATA WT-1305, WT-1303, WT-1408, WT-1417, WT-1348, WT-1349, WT-1340, AD-361774 AD-339277 AD-344937 AD-360872 AD-362108 AD-361977 AD-357964 MS Ardith Jarrett, at Ardith JOSEPHINE WOOD Chief Technical Support