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    D IS TR IBUTION STATEMENT AA p pro ve d fo r P u blic R e le as eD is tr ib u t io n U n l im i te dPNE - 510F

    UNITED STATES ARMY CORPS Of ENGINEERS

    BRUNEAU PLATEAU , IDAHO30 Septem ber 1965

    PRO J E C Tr I B - S C H O O N B R D

    DESIGN, CONSTRUCTION, AND POSTSHOTEVALUATION OF CONCRETE STEM

    FOR ACCESS HOLEKENNETH L. SAUCIER, PROJECT OFFICER~ - - - - - - - - - - - - - - - - ~LOVELACE FOUNDAT ION F. STEWART

    U. S. Army Enginee Waterways Experiment StationDOCUMENT LIBRARYVick rg, Mississippi 7 tJU.S. A rm y Engineer Nuclear Cratering G roup

    liverm ore, Cal ifo rnia TSSUED: August 1967

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    LE GAL NOTICEThis report was prepared as an account of Government sponsored work. Neither the UnitedStates, nor the Commission, nor any person acting on behalf of the Commission:

    A. Makesanywarranty or representation, expressed or Implied,with respect to the accu-racy, completenesa, or usefulnees of the Information contained Inthie report, or that the ...eof any Information, apparatus, method, or process disclosed In this report maynot Infrlllleprivately owned rights; or

    B. Assumes any llabilltles with respect to the use of, or for damages resu1Unc from theuse of any Information, apparatus, method, or proces_ disclosed Inthis report.

    As used In the above, "person acUDgon behalf of the Commission" Include_ any em-ployee or contractor ~f the Commls.lon, or employee of _ucb contractor. to the extent tJaat_ucb employee or contractor of the Commission. or employee of _ucb coatractor prepar...dl.semlnates. or proTIde. acce._ to, any InformatiODpur_uant to bI_ eaploya_t or coatnctwith the Coaml_.loa. or hi. employment with _ucb coatractor.

    Printed in the United States of AmericaAvailable fromClearinghouse for Federal Scientific and Technical InformationNational Bureau of Standards, U. S. Department of CommerceSpringfield, Virginia 22151Price: Printed Copy $3.00; Microfiche $ 0 . 6 5

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    PRO JECT PRE -SCHO ONER IIPNE-510-FDE SIG N, CONSTRUCTION, AND PO STSH OT E VALUATION O FCONCRETE STEM FOR ACCESS HOLE

    Kenneth L . Saucier, Proj ect OfficerF. S. StewartU. S. Army Engineer Waterways Experiment

    StationCorps of EngineersVick sburg, Mississippi

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    ABSTRACT

    Project Pre-Schooner II consisted of a lOO-ton chemical explosivedetonated in hard, dry rock at a depth of 71 feet. The primary pur-pose of the project was to increase the knowledge of crater dimen-sions in hard, dry rock as a function of depth of burst and type ofexplosive. This report describes the proportioning of a concretemixture used in stemming the access hole of the shot cavity, the de-sign of the stem configuration, laboratory tests conducted on coresamples from the site and on specimens of the concrete mixture re-quired for design of the stem,. and placement of the concrete at thejob site. Based on observations of the detonation, fractured piecesof the reinforced concrete stem, and the size of the crater, it isbelieved that the stem acted effectively to stem the detonation.

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    PREFACE

    The work described in this report was authorized by MIPR No.NCGlAO 8-65, Change No.1, dated 12 May 1965, from the U. S. ArmyEngineer Nuclear Cratering Group, Livermore, California, to theU.' S . Army Engineer Waterways E xperiment Station (W ES).

    The work was performed at the W ES Concrete Division and theBruneau Plateau region of southwestern Idaho under the supervisionof Mr. Bryant Mather, Chief, W ES Concrete Division, and Messrs.James M. Polatty, William O. Tynes, and Kenneth L. Saucier, ProjectOfficer. This report was prepared by Messrs. Saucier and Frank S.Stewart.

    Director of the W ES during the conduct of this investigationand preparation of this report was CO L John R. Oswalt, Jr., CEoTechnical Director w as Mr. J. B. Tiffany.

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    CONTENTS

    A B S T R A C T - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 3P R E F A C E - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 4CONVERSION FACTORS, BRITISH TO METRIC UNITS OF M E A S U R E M E N T - - - - - - - 7I N T R O D U C T I O N - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 8

    Description of Pre-Schooner II S h o t - - - - - - - - - - - - - - - - - - - - - - - - - - - - 8O b j e c t i v e s - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 9B a c k g r o u n d - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 9T h e o r y - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 9

    P R O C E D U R E - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 1 1Experimental P 1 a n - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 11Concrete Mixture Used for S t e m m i n g - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 11Laboratory Tests of Concrete and F e 1 s i t e - - - - - - - - - - - - - - - - - - - - - - - 1 3

    R E S U L T S - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 1 5Access Hole G e o 1 o g y - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 15Laboratory Tests of Concrete and F e 1 s i t e - - - - - - - - - - - - - - - - - - - - - - - 1 5

    STEM D E S I G N - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 1 6A p p r o a c h - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 16C a 1 c u 1 a t i o n s - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 1 7

    F I E L D W O R K - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 1 9POSTSHOT R E S U L T S - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 2 0

    Laboratory Tests of C o n c r e t e - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 20Field S u r v e y - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 2 1C O N C L U S I O N S - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 2 2R EFE RE NCE S- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- - 27

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    FIGURES1 Cross section of Pre-Schooner II chemical-explosive

    c h a r g e - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 232 Punch-out test specimen with concrete filler in place- --- -- - 243 Loading apparatus for punch-out tests with specimenin p l a c e - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 254 Mohr- circle analysis for shear strength determination;p orp hy rit ic fe lsi te an d fe lsi ti c vit rop hy re- -- -- -- -- -- -- -- -- 2 6

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    CONVERSION FACTORS, BRITISH TO M ETRIC UNITS OF M EASUREM ENT

    British units of measurement used in this report can qe convertedto metric units as follows:

    MultiEl~ B~ To Obbad.ninches ~ 5 . 4 lllillimeterssquare inches 6 . 4 5 1 6 ~ q ua re c en ti me te rsfeet 0 . 3 0 4 8 metersmiles 1 . 6 0 9 3 4 4 kilometerscubic feet 0 . 0 2 8 3 1 6 8 c ub ic me te rsc ub ic y ar ds 0 . 7 6 4 5 5 5 c ub ic m et er spounds 0 . 4 5 3 5 9 2 3 7 kilo~ra,mstons 9 0 7 . 1 8 5 kilogramspounds per square inch 0 . 0 7 0 3 0 7 k ilograms per square centimeter

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    P RO J EC T P RE - SC HO O NE R IIDESIGN, CONSTRUCTION, AND POSTSH OT EVALUATION OF

    CONCR ETE STEM FO R ACCESS H O L E

    INTRODUCTION

    DE SCR IPTIO N O F PR E- SCH OO NE R II SHOTP ro je ct P re -S ch oo ne r IIwas a chemical explosive single-charge

    cratering experiment in hard, dry rhyolite rock executed by theU. S. Army Engineer Nuclear Cratering Group as a part of the jointAtomic Energy Commission-Corps of Engineers nuclear excavation re-search program. Pre- Schooner IIwas detonated on 30 September 1965about 5:10 p.m. (Mountain Standard Time) on Bruneau Plateau, ap-prox imately 40 milesl southwest of Bruneau, Idaho. The emplacementhole was at the following coordinates: long. 11534'25.203"W,lat. 42024'02.943''N (Modified Idaho State Coordinate System -N 267,639.53; E 547,783.11). The cavity, located at a depth of71 feet, contained approximately 85.5 tons of nitromethane(CH3N02) at zero time. The detonation resulted in a crater withan apparent crater radius of 95.2 feet, an apparent crater depthof 60.7 feet, and an apparent crater volume of 24,780 yd3.

    1 A table of factors for converting British units of measurementto metric units is presented on page 7.

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    reinforced concrete stem) utilizing shear keys if necessary) was con-sidered to be the most practical design for this purpose (seeFigure 1).

    The basic criterion was to design the total bond-shear resis-tance of the concrete-felsite interface to be at least equal to thetotal unconfined) static shear resistance of the felsite by usingbond-shear strength of concrete to felsite and shear keys as neces-sary. The resistance capacity of the stem was considered separatelyin each stratum of felsite. Shear keys) if required) could be de-signed from a dynamic approach) since literature on this particularsubj ect is available.

    Other pertinent criteria were as follows:1. The 21-day strength of the concrete design proportioned at

    the U. S. Army Engineer waterways E xperiment Station (W ES) and curedunder optimum conditions in the laboratory was to be reduced 15 per-cent for design calculations because of unknown field curing condi-tions and the uncertainty of the detonation schedule.

    2. For ease of mining) the key was to be of the "dovetail"type) designed shoulder down) with a convenient ratio of key shouldersize to key height.

    3 . There was no requirement for vertical steel in this designapproach.

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    PROCEDURE

    EXPERIMErNTAL P IANThe stemming material was to be a concrete mixture proportioned

    to match as closely as possible the structural properties of the insitu material. Core samples taken from the jobsite were to beshipped to the laboratory for testing. The test results were to beused to design the stem configuration. The concrete would be placedin the shot hole using recommended procedures and allowed to cure.Observation of the detonation, crater, and pieces of fractured stemwould assist in evaluating t~e effectiveness of the stem.

    Considering the structural properties, it was obvious that thecontinuous medium would not react in the same manner as the laboratoryspecfmens , The standard tests for tensile~ shear, and compressivestrengths are unconfined tests on specimens extracted from the con-tinuous medium. Thus, in reality, the application of unconfined testvalues in lieu of confined test values is only an a:pprox1n).a.tion.Nevertheless , it was deeroed appropriate to Use this approach dueto the many unpredictable and uncertain facets inherent in crateringphenomena today and the practical limitations on an extensive designstudy.CONCRETE MIX TURE USED FOR STEMMING

    The concrete mixture for use in t~e stemming was proportioned to

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    have a cement factor of 7 . 5 bags/yd3 , a water-cement ratio of 0 . 4 6by weight, and a slump of 3 - 1 / 2 + 1 / 2 inch. The mixture proportionsare presented in the following tabulation.

    BATCH DATA BASED ON ONE BAG OF CEMENTMaterials Solid Volume S at ur at ed S ur fa ce -Dry Weight

    yd3 lb0 . 4 7 9 9 4 . 0 00 . 0 8 5 3 0 . 0 00 . 8 2 0 1 3 2 3 01 . 5 2 2 2 4 7 . 6 00 . 6 9 4 4 3 . 2 4

    5 0 00 . 2 5

    Type III p or tl an d c eme ntM et al li c a gg re ga teCrushed natural sandCrushed natural coarse aggregateWaterC on cr et e c ol or in gw at er -r ed uc in g a dm ix tu re( li gn in b as e)

    At each quarter height of the stem the concrete coloring was to bechanged to aid in the postshot study of crater ejecta. The metallicaggregate, a commercial product consisting primarily of iron filings,was used to increase the density and prevent shrinkage of the mix -ture. The coarse aggregate was nominal l-l/4-inch maximum size,crushed natural chert. The grading of each of the aggregates ex -cept the metallic was as follows:

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    Sieve Size Cu mul ati ve Pe rce nt P ass ingC oa rs e A gg re ga te F in e A gg re ga te

    1-1/2-inchl-inch3/4-inch1/2-inch3/8-inch

    100.09 7 17 7 741.221.0 100.0

    No. 4No. 8No. 16No. 30No. 50

    1.9 99085665534511.3

    No. 100No. 200 4 51.8

    The specific gravities of the coarse and fine aggregates w ere 2.61and 2.59, respectivelYj the percentage of absorption was 1.2 forb ot h a gg re ga te s.

    LA BO RA !IO RY TESTS O F C ON CREl'E A ND FELSITEBond-shear, tensile, and compressive-strength tests were con-

    ducted on the concrete to obtain data for comparison w ith the prop-erties of the felsite at the test site. A description of theset es ts f ol lo ws .

    The purpose of the bond-shear or punch-out tests was to simu-late, on a small scale, the effect of the blast on the concrete stem.Six-inch-diameter cores obtained from the test site w ere sawed into

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    lengths ranging from 3 to 12 inches. These specimens were thengrouted into a square form to furnish stability during the drill-ing of a 3-inch-diameter hole through the center of each specimen.The holes in the specimen were then filled to different depthswith the stem concrete mixture, which was allowed to cure for 7days. In each specimen, the top end of the concrete "plug" wascapped with a high-strength gypsum compound. A typical specimenis shown in Figure 2. Each specimen was placed and grouted in astabilizing frame with the high-strength gypsum plaster to producea condition of biaxial confinement. The frame was placed in a440,ooo-pound- capacity testing machine; a 3- inch- diameter steelpiston was placed on the capped concrete plug, and the entireassembly was carefully leveled to avoid eccentric loading. Thepiston was loaded (Figure 3) until the bond between the concreteand felsite failed.

    Dynamic tensile- splitting strength (crt) a nd compressive strength(0 ) tests were performed on the felsite and stemming concretecto obtain data for use in the design analysis and to compute shearstrength. The shear values (c) used in the calculation were ob-tained from the dynamic compressive and tensile strength valuesplotted on a Mohr's circle. The shear strength analysis is pre-sented in Figure 4 (Reference 1).

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    RESULTS

    ACCESS HOLE GEOLOGYThe geologic condition of the Pre-Schooner II site was as

    follows:

    Depth Descriptionfeet0-7 Residual soil7-40 Layers of felsitic vitrophyre, volcanic breccia, andfractured porphyritic felsite

    40-62 Porphyritic felsite, hard dense, some areas highlyfractured

    LABORATORY TESTS OF CONCRETE AND FELSITEThe averages of the results of the various tests are given

    below:

    T es t P ro pe rt y Felsitic Porphyritic ConcreteV it ro ph yr e F el si tePunch-out ( bo nd -s he ar ) s tr en gt h, p si 2,230 1,950D yn am ic c om pr es si ve s tr en gt h, c r(unconfined), psi c 5,860 18,800D yn am iC t en si le s pl it ti ng s tr en gt h,c rt ( u nc o nf i ne d ), p s i 715 1,675D yn am ic s he ar s tr en gt h, C ( co mp ut ed ),ps i 1,010 2,770Static compressive strength, f' ,. c 6,700PSl.Note: The concrete in the punch-out tests had been cured for 7 days.The concrete in the strength tests had been cured for 21 days.

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    4., Compute the dynamic shear resistance of the shear keyuSingt1l.e,appropr,iate dimensions and the follow ing ex pres sion(Reference 3). f or o ne u nre inf or ced ke y:

    l' = 0.64f'cwhere

    l' = shear resistance, psif' = compressive strength of concrete, psic

    5. Computeaddi tional shear strength supplied by usingreinforcing steel bars ..and applicable design recommendations for shearstre:qgth of st ee'L (21,000 psi is taken from page 9 of Norris andothe.rs (Reference 2)).

    ., ..,. 6. Compute total force available, and check against shearres1stan(! e to match the felsite (computation 3).

    ,7. Compute the required length of steel bars to fullydevelop the dynamic bond on each side of the shearing plane. Norrisand oth~rs (Reference 2), page 46, recommended an ultimate dynamicbond stress of 0.15f'.. cCALCULATIONS

    Field iogs indicated a stratum of felsite at a depth of 40 to62 feet. A key was required to match the shear strength for 22 feetof felsite, and the following calculations were used to design thekey:

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    1. Shear resistance of felsite (interface area) = holec ir cum fe re nce ( in ch ) X shear strength (psi) X height of felsiteregion (inch) = 113 X 2,770 X 22 X 12 ~ 8.26 X 107 pounds.

    2. To obtain available concrete bond-shear resistance, an8-foot-high key was assumed; 12 feet of circumferential area wasavailable for bond. Hole circumference (inch) X bond shear (psi)X height of felsite region (inch) = 113 X 1,950 X 12 X 12 ~ 3.17X 107 pounds.

    3. A key was needed to provide the additional 509- X107_pound (8.26 x 107 - 3.17 X 107) r es is tan ce .

    4. Unit shear resistance (~ ) of a key = 0.64f' X 0.85.c(The strength of the laboratory-proportioned concrete was reduced15 percent for design calculations because of the uncertainty offield curing conditions.) Hole circumference (inch) X compressivestrength of concrete (psi) X height of key (inch) = 113 X 0.64 X6,700 X 96 ~ 4.65 X 107 pound.

    5. Ten No. 10 reinforcing steel bars per foot were addedto provide additional strength. A double area of 2 X 1.27 in.2 =2.54 in.2 The dynamic shear strength of steel is taken as 21,000 psi.The doubled diameter (inch) X shear strength of steel (psi) X num-ber of bars per foot X height of key (foot) = 2.54 X 21,000 X 10X 8 ~ 0.43 X 107 pound.

    6. The available force (sum of calculations 2, 4, and 5),

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    8.25 x 107 pounds;- adequately matches the required force (calci.ila':'tion 1).

    7. The following procedure was used to determine the re-quired length of steel 'inthe keywayto develop sufficient bond.

    ,", . . ~ ~ "'-(a) f' (psi) = 0.85 X 6,700 ~ 5,700 c(b) Bond strength (psi) = 0.15 X 5,700 ~ 860

    (c) Circumference of No. 10 bar (inch) = 3.99 (d) Bond strength per inch of bar length (pound)

    = 3.99 X 860 ~ 3,430 (e) Force developed in each bar (pound) = 21,000

    X 1.27 = 26,670 , \.

    (f) Length of steel bars required in the keyway,to,deyelop,sufficient bond ,= 2~;f~g ;: 7.78 inches .,

    An 8-foot-:-high key with a lip depth of 3.0 feet and ten No. 10reinforcing steel bars (8-inch minimumbonded lengtl;:t) per foot ofkey.heigl;:ttwas recommended..

    FIELDWORK

    .~e, sphere and.key cqnfigwai:;ion was.mil'ledas shownin Figure 1.The reinforcing steel was.placed, in the key, and the. first lift ofconcrete, was rp.laced covering the. reinforcing steeL The secondlii't, placed 24 pours later"brought th~stem to:the ground surface.The concrete was .co.Lor'ed withvar:i,qus i colors at differel'lt depths, as

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    shown below, to aid in postshot identification of recovered piecesof stem.

    Lift Color D ep th I nt er va lsfeet

    1 Yellow Top of sphere to 522 Green 52 to 432 Brown 43 to 202 Terra-cotta 20 to ground surface

    P OS TS HO T R ES UL TS

    LABOR ATO RY TE STS OF CO NCR ETEFi~ld-cast specimens from the reinforced concrete stem, 6- by

    l2- inch cylinders, were sent to the WE S where they were tested on thedetonation date. The specimens were 21 days old at time of test.Results are given below . The static strength results (approximately9,000 psi) are indicative of high-quality concrete and undoubtedlyresulted in higher bond and shear strengths than those used in thestem design (see page 18). To gain some knowledge of the impactproperties of the concrete, dynamic compressive strength tests w ereconducted on several specimens. R ise time w as approximately 1 msec.As shown in the following tabulation, the dynamic strength of the con-crete was approximately 25 percent greater than the static strength.

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    Depth Color of Stem Static DynamicInterval Concrete Portion Compressive CompressiveS tr en gt h, a strength,b2l-Day Age 2l-Day Agefeet psi psi

    62 to 52 YelloW" LoW"er key 8,670 10,87052 to 43 Green Upper key 8,510 11,50043 to 20 Brown Midstem 9,370 11,72020 to 0 T er ra - c ot ta Top stem 9,120 11,050-

    Average 8,920 11,280: Each value is the average of four tests.Each value represents one test

    .FIE LD SUR VE YSliding and sloughing of the sides prevented entry into the

    crater proper, and a thick covering of dust severely hampered thesearch for pieces of the concrete stem. Several small pieces ofgreen and yellow concrete, none larger than 1 ft3, indicated thathigh compressive forces had acted on the lower stem as expected.These pieces were highly fractured, through both the mortar and theaggregate. Three small pieces of reinforcing steel, the largestapproximately 1foot long, were located at various distances from thecrater rim. The broken steel gave evidence of large shearing forcesalthough the concrete had been stripped from the steel. No pieces

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    of concrete stem from the upper sections, color-coded brown and terra-cotta, were located.

    CONCLUSIONS

    Based on visual observations of the detonation and of fracturedpieces of the reinforced concrete stem, the stem effectively con-tained the shot as no evidence of 'blowout" was detected. The di-mensions of the apparent crater (95-foot radius, 60-foot depth),when compared to the predicted dimensions (75-foot radius, 40-footdepth), also indicated an effective stem.

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    Ji.C",I PlOD' eMI;""'_""/:-",~ T' """,

    ~ .t6?Mm6IJr~/',;.", ,,.,..Is /$.4-q'tr')

    ..~- DWN.t &>It 18 ~_', eMi" A__A t> < - - ~i" ~ ..t' M-L'{~/,Io') , rao AN'I.EtIlvAr_ ruN0,., . a . - . . .".-tb,C,,'{'A.s.~o.oo r .ass:S:S~""~,,rv~,8o""t., E..t\r,,~ ' I'. I

    I

    Figure 1 Cross section of Pre-Schooner II chemical-explosive charge.2 3

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    a. Top view showing high- strengthgypsum plaster cap on concretefiller.

    b. Side view ( 3 - 5 / 1 6 inches cor-responds to the height of concretefiller from the base to the cap).

    Figure 2 Punch-out test specimen with concrete filler in place.

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    Figure 3 Loading apparatus for punch- out testswith specimen in place.

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    4,000iiia.sIf-oz 2,000Wa :f-IIIa :wI CIII

    02,000 0

    at

    iiia.~ 8,000If-ozWa :f-IIIa : 4,000WIIII

    12,000

    II~ -~I

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    REFERENCES

    1. R. G. Wuerker j "The Shear Strength of Rocks ": Mining E ! r l : : _ 'gineering, October 1959, Vol 11, Pages 1022-1026j Unclassified.

    2. C. H. Norris and othersj "Structural Design for DynamicLoads" j 1959 j McGraw-Hill Book Company, Inc., New York, N. Y. jUnclassified.

    3. Indraradan Shahj "Dynamic Shear Strength of Concrete Key's"jR-63-5, January 1963j Massachusetts Institute of Technology,Ca mbr id ge, Ma ss .j Unc la ssi fie d.

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    DISTRIBUTIONNo. of CopiesL RL I nt er na l D is tr ib ut io n

    D ir ec to r' s O ff ic eInformation Department 2R. BatzelJ . BellJ . Carothersw . Deckers . FernbachR. GoeckermannJ. GofmanE. GoldbergJ. Hadleyw . HarfordC. H au ssm an nR. HerbstG. HigginsA. Holzer 2E. HulseJ . KaneJ . Knox 2J . KuryC . M cD on al dM. Nordyk,e 2J. Rosengren

    28

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    Di.tribution L ist, cont'd. Bo. of Copiesi.~B.,Rubin.:

    D. SewellP. StevensonH. TewesC. Van AttaG. Werth

    r m . Berkeley,R . K . WakerlingD. M. Wilkes

    E . Teller

    22

    I RL M er cu ry ,L . Crook s

    E x ternal Distribution,T JJ ). .45 00 ,U C- 35 , N uc le ar E xp lo si on s - . Pe ac e1 "u lApplications

    . Department of Mines and Technical SurveysCanada

    277

    D. J. Convey 2Oil and Gas Conservation BoardCanada

    G. W. Govier 2U. S. Army Engineer Division, Lower Mississippi ValleyVick sburg, Mississippi

    U. S. Army Engineer District, MemphisM em ph is , T en ne ss eeU. S. A~ Engineer District, New OrleansJew O rl ea ns , L ou is ia na

    29

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    Distribution L ist, cont'd.U. S. Army Engineer Waterways Experiment Station

    . Vi ck sb ur g, M is si ss ip pi

    No. or Copies75

    U. S. Army Engineer District, St. LouisSt. Louis, Missouriu . S. Army Engineer District, VicksburgV ic ks bu rg , M is si ss ip pi

    U. B. Army Engineer Division, MediterraneanAPO, New YorkU. S. Army Liaison DetachmentNew York, New Yorku . S. Army Engineer District, GULFAPO, New York

    U. S. Army Engineer Division, Missouri RiverOmaha , Nebraska 2u . S. Army Engineer District, Kansas CityKansas City, Missouriu . s . Army Engineer District, OmahaOmaha, Nebraska

    U. s . Army Engineer Division, New EnglandW al th am , M as sa ch us et tsu . s . Army Engineer Division, North Atlanticlev York, New York

    U. S. Army Engineer District, BaltimoreB al ti mo re, M ary la ndU. S. Army Engineer District, New YorkNew York, New YorkU. S. Army Engineer District, NorfolkN or fo lk , V ir gi niaU. S. Army Engineer District, PhiladelphiaP hi la de lp hi a , P en ns yl va ni a

    U. B. Army Engineer Division, North CentralC hi ca go , I ll in oisU. S. Army Engineer District, Buft'aloat:t:ralo,lev York

    30

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    Distribution List, cont'd.U. S. Army Engineer District, ChicagoC hic ag o, Il lin oi sU. S. Army Engineer District, DetroitD et ro it , M ic hi ga nU. S. Army Engineer District, Rock IslandRock Island, IllinoisU. S. Army Engineer District, St. PaulSt. Paul, MinnesotaU. S. Army Engineer District, Lake SurveyDe tr oit , Mic hi gan

    U. S. Army Engineer Division, North PacificPortland, O regon

    u . S. Army Engineer District, PortlandPortland, O regonu . S. Army Engineer District, AlaskaA nch or age , A las kau . S. Army Engineer District, SeattleS ea tt le , W as hi ng to nu . S. Army Engineer District, Walla WallaWalla Walla, W ashington

    U. S. Army Engineer Division, Ohio RiverCincinnati, OhioU. S. Army Engineer District, HuntingtonH untington, W est Virginiau . S. Army Engineer District, LouisvilleL ou is vil le , K en tu ck yu . S. Army Engineer District, NashvilleN as hv il le , T en ne ss eeu . S. Army Engineer District, PittsburghP it ts bu rg h, P en ns yl va ni a

    U. S. Army Engineer Division, Pacific OceanHonolulu, Hawa 11U. S. Army Engineer District, Far EastAPO, San Francisco, California

    3 1

    . 0 . ot Cop1e.

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    D is tr ib ut io n L is t, c on t' d.u~S. Army E ngineer District, H onoluluH on ol ul u, H aw ai iu . S. Army E ngineer District, O kinaw aAPO , San Francisco, California

    u . S. Army E ngineer Division, South AtlanticA tl an ta , G eo rg iaU. S. Army Engineer District, CanaveralMerritt Island, FloridaU. S. ArmY- Engineer District, CharlestonC ha rle st on , S ou th C ar ol in aU. S. Army Engineer District, J ack sonvilleJacksonville, FloridaU. S. Army Engineer District, MobileM ob il e, A la ba maU. S. Army Engineer District, SavannahS av an na h, G eo rg iaU. S. Army E ngineer District, W ilmingtonW il mi ng to n, N or th C aro li na

    U. S. Army Engineer Division, South PacificS an F ra nc is co , C al if or ni a

    u . S. Army Engineer District, Los AngelesL os A ng el es , C al if or ni aU. S. Army Engineer District, SacramentoSacramento, CaliforniaU. S. Army Engineer District, San FranciscoS an F ra nc is co , C al if or ni a

    p . S. Army E ngineer Division, Southw esternD al la s, T ex asu . S. Army E ngineer District, Albu~ uerq ueAlbu~ uerq ue, New Mex icoU. S. Army Engineer District, Fort WorthForth W orth, Tex asU. S. Army Engineer District, GalvestonG al ve st on , T ex as

    32

    No. of Copies

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    U. S. Army Engineer Nuclear Cratering GroupLivermore, California 74

    D is tr ib uti on L is t, c on t' d. No. of CopiesU. S. A~y Engineer District, Little RockL ttle R ock , Ark ansasU. S. A~y Engineer District, TulsaT ul sa , O k la ho ma

    U. S. A~y Coastal Engineering Research BoardWashington, D. C.M is si ss ip pi R iv er C om mi ss io nVicksburg, MississippiRivers and Harbors, Boards of EngineersW ashington, D. C.Corps of E ngineers Ballistic Missile Construction O fficeNorton Air Force Base, CaliforniaU. S. A~y Engineer CenterFt. Belvoir, VirginiaU. S. A~y Engineer Reactors GroupFt . Belvoir, VirginiaU. S. A~y Engineer Training CenterFt. l eo na rd W oo d, Mi ss ou riU. S. Army Engineer SchoolFt. Belvoir, Virginia