Bearing capacity model test of stratified subsoil loaded by strip foundation. Technical note

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782132 STUDY OF SKIN FRICTION ON PILES IN STIFF CLAY Parry, R H G; Swain, C W Grouni Engng, Vl0, N8, Nov 1977, P33-37 In stiff clays the horizontal direct effective stress in a soil clement adjacent to a pile face is likely to be at least equal to, amd probably greater than, the vertical direct effective stress. This places restrictions on the skin friction which can be developed on the soil-pile interface anl these are explored by means of Mohr-Coulomb stress diagrams. It is also shown that a relationship can be established between effective stress and total stress methods of calculating skin friction. 782133 R E i N OF THE PRECAST PILE Curtis, R J Ground Engng, VI0, NT, Oct 1977, P24-26,42 Discusses the Jointing system now being used with l~ecast concrete piles amd how this has increased the adaptability of the system to the extent that its use is new on the increase. 782134 SWEDISH RIG BRIhDS FINE ART INTO PILINQ Byles, R New Civ Engr, N274, 5 Jan 1978, P16-17 Briefly describes the Banut 400 hydraulic piling rig, ntilising a 3t free fall hydraulically lifted drop hammer operatimg in its own cage. Hammer drop distance, blow rate and blow count can be automatically ad4usted, amd the leader can be raked 1:3.5 forwards, i:i backwards and 1:8 laterally.

782135 ICE PILIND GUIDE: BETTER LATE THAN NEVER New Civ Emgr, N272, 8 Dec 1977, P22-29 The Institution of Civil Engine,s (ICE) was due to publish its long-awaited guide, 'Piling: model procedures and specifications' in January 1978. This article traces the 9-year development of the document, which includes contract procedures, model special clauses and bills of qt~uutities and a model specification, as well as model l~OCedures and a model specification for site investigation work. Two views from industry are included, but the document is not discussed in detail. 782136 ~ F E C T OF SOIL SET UP ON PILE DRIVEABILITY IN CHALK ViJayvergiya, V N; Cheng, A P; Kolk, H J J Geotech Engr~ Div ASCE, VI03, NGTI0, 1977, P106~1082 Data obtained from pile driving in chalk in the North Sea oil fields is analysed in terms of relative set t~p, FR, defined as the ratio of driving resistance after a delay to the resistamce before delay. FR increases with delay time. Soil resistance during driving may increase by as much as 80 per cent if significant delays occur. A good comparison is obtained between computed static pile capacity amd an estimate made by extrapolating the increased resistance during driving. 782137 FOUNDATION STABILITY ON NONHOMOGENEOUS CLAYS Murff, J D; Miller, T W J Geotee/~ Engng Di~ ASCE, V103, NGT10, 1977, P1083-i095 A method for approximating the besting capacity of shallow rectangular foundations on nonhomo-

gereous clays subjected to inclimed, eccentric loadimg is presented. The method is based on upper boumd plasticity concel~s with two simple collapse mechanisms beimg considered. The solutions agree well with existir~ exact s_nd empirical methods. 782138 PROGRESS IN MARINE GEOTECHNICAL ENGINEERING Foeht, J A; Kraft, L M J Geoteah E r ~ Div ASCE, VI03, h~{fl0, 1977, P1097-1118 This paper reviews ~ogress made in the past 30 years in several sreas of marire geotechnical engineering includimg Jack-up rigs, piles, gravity structures, object penetration and breakout resistance, seafloor stability and geotechnlcsl data acqulstion. This progress is illustrated by reference to major events such as hurricanes, project plannir~ for ~=w areas, installation of specific structures and research projects. 782139 APPLICATION OF THE WAVE EQUATION ANALYSIS TO FRICTION PILES IN SAND Tavemas, F A; Audlbert, J M E Can Geotech J, VI4, N1, Feb 1977, P3~-51 The application of the wave equation method to instrumented precast concrete piles driven under well controlled conditions leads to excel~ent predictions both in terms of driving stresses and of ultimate bearing capacities. The same high quality of prediction is obtained for a steel H-pile and a precast concrete pile driven incrementally to a depth of 53 ft in a uniform sar~ deposit. However, proper simulation of the Joints is required for the precast concrete pile. On the contrary, a very poor correlation between computed and observed ultimate capacities is obtained for the production piles. This is attributed to the poor reliability of the blow counts used as input data in the classical wave equation method of analysis. 782140 APPLICATION OF P R E S S ~ TEST RESULTS IN DEFORMATION ANALYSES Burgess, N; Eisenstein, Z Can Geotech J, V14, N1, Feb 1977, P64-75 The present study is a continuation of work on pressuremeter testirg with a view to develo/~ ing a pragmatic approach to a complex problem of foundation deformation analysis. Described in detail are pressuremeter tests Omthree sites in Western Canada where documented case histories of deformation behavic~rwere available. At all three sites the pressuremeter derived moduli were used in back-analysis of foundation behaviour ard the results were compared with previously recorded field data. An agreement between the back-armlysis and field data in sc~e cases and discrepancies in others irzllcatms the limitations of this approach to pressl~remeter testing in these types of four~ation materials. The results are discussed and conclusions are drawn on the basis of these as well as the previously studied case histories. 7821~i B E A R I ~ CAPACITY MODEL TEST OF STR/~IFIED SUBSOIL LOADED BY STRIP FOUNDATION. TECHNICAL NOTE TeJchman, A Can Geotech J, Vl4, N1, Feb 1977, P138-143 The paper presents the results of model tests concerning the bearing capacity of a strip

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foundation resting on stratified subsoil. The foundation was loaded with vertical and inclined forces, acting axially and eccentrically. The subsoil ass~ned for the testing consisted of a strong layer overlying a weak one. Three principal problems were analysed based on results obtained from the model tests as follows: the effect of stratified subsoil on the foundation's bearing capacity, the effect of the loading system on the foundation's bearing capacity, and the effect of stratified subsoil on the settlement of the foundation. In the concluding remarks the mechanism of failure for stratified subsoil and practical notes on the soil bearing capacity under the analysed conditions are presented. 782142 D~.'~L~£1NATION OF THE BEARING CAPACITY AND ~ I O N ~SZSTANCE oF Pn~Es BY s o u ~ z m s (IN GEP~AN ) Rollberg, D P~bl Inst Found Eng, Soil Mech# Rock Meah, Waterways ConW~, ~3, 1977, P%3-224 782143 RESULTS OF TESTING DR]V.L~ CAST-IN-SITU PILES IN PLASTIC FROZEN GROUND (IN RUSSIAN) Cherniaev, V I; Mironov, V A Transp Strolt, NIl, NOV 1976, P49-51

782149 SOME EXAMPLES OF THE INFLUENCE OF FIELD MEASUREMERTS ON FOUNDATION DESIGN AND CONSTRUCTION Burland, J B Paper to 6th Regional Conference for Africa on Soil Mechanics and Foundation Engineering, Durban, Sept 1975 Briefly describes a variety of instruments and their use in observing the movement of the ground beneath and around foundations - these Include precision surveying equipment, inclinometers and borehole extensometers. Presents a n t ~ e r of case studies including designing for mining subsidence, the founding properties of chalk, foundations on stiff clays and the design and behaviour of deep basement excavations. Avail: BIKE, Garston, Watford, WD2 7JR, UK (CP I1/77 ) 782150 PILES IN WEAK ROCK London: Inst of Civil Engineers, 1977, 233P A reprint of the collection of papers first published in Geotechnique, March 1976 , covering piles in mudstone, chalk, weathered diabase, bored and driven piles, rock socket piles, testing and instrumentation.

782!4~ FOUNDATIONS ON FROST-HEAVING GROUND (IN RUSSIAN) Tolkachev, N A Zhilishchnoe stroit, N3, March 1977, P18-21

782151 PILE FOUNDATIONS (IN RUSSIAN) Glotov, N M; Luga, A A; Silin, K S Moscow: Transport, 1975, 431P

782145 TAPERED PILES FOR INDUSTRIAL CONSTRUCTION (IN RUSSIAN) lurchlshln, N G Stroit Truboprov, N5, May 1977, P34-35

782152 RECOMMENDED PRACTICE FOR THE DESIGN AND CONSTRUCVfION OF BASES AND FOUNDATIONS ON THAWED PERMAFROST (IN RUSSIAN) Moscow: Akad Stroit Arkhit, Nauch-issled Inst 0snov Podzemn Soorttzh, 1974, llTP

782146 CALCULATION OF FOUNDATION S E T T ~ N T ALLYING FOR VARIATIONS IN THE DEFORMATION PROPERTIES OF GROUND (IN RUSSIAN) Krivorotkov, A P Russia: Minlst Vyssh Sred~go Spet~ Obrazov, Izv VUZ Stroit Arkhit, NB, 1977, P17-22 782147 SMALL DIAMETER PILES IN KARSTIC ROCK David~ D; Sroka, E; Goldberger, M Proc 9th International Conference on Soil Mechanics amd Foumdation Engineering, Tokyo, 1977, V1, P471-473 Reports the use of a newly developed drilling machine capable of advancing 30era holes at about 5 ~ h in the hard rock, and the use of small diameter piles with high skin friction values in Karatic rock containing clay pockets. 782148 DYNAMIC CONSOLIDkTION OF ROCKFILL AT UDDEVALLA SHIPYARD Hansbo, S Proc 9%h Int~'~%l ~ l Conference on Soil Mechanics and Foundation Engineering, Tokyo,

1977, V2, P241-246 Reports the use of rockfill t~ provide a foundation w i ~ a high modulus of deformation for the quays and crane tracks at Uddevalla, Sweden. The rockfill layer has a maximum thickness of about 30m ani was compacted by the heavy tamping method usimg 40t and 14t weights. This paper concentrates on the methods used to assess the compaction, concluding that seismic measuremerits in c o , unction with retardation tests of the falling weight proved to be sufficiently accurate tools to replace the expensive plate loading test, and that pressuremeter tests were not so useful.

782153 CONSTRUCTION OF ARTIFICIAL FOUNDATIONS Ganlchev, I A US Arm~ Cold Regions Research & Engineering Lab translation TL 545, Sept 1976, ll4P Comprises the translation of a section of a Russian book dated 1973, the only part included being that on the USSR. Avail: NTIS, Springfield,

Va, 22161, USA (ADA

030322 ) 782154 USE AND INFLUENCE OF BENTONITE IN BORED PILE CONSTRUCTION Flemimg, W K; Sliwlnski, Z J Dept of the Envlronment/Construction Industry Research amd Information Association Piling Development Group report PG3, Sept 1977, 93P Reviews research on pile friction and analyses full scale loading tests covering about 50 sites, representing a wide range of ground corzlitions. Concludes that narmslly the bahaviour of piles in cohesive soils is unaffected by the presence of bentor~te. However, evidence from more difficult groumd conditions (such as cohesionless soils under high piezometric presm2res) is limited and no conclusions can be drawn. Avail: CIRIA, 6, Storeys Gate, London SWIP 3AU, UK 782155 INI~EGRITY TESTING OF PILES: A REVIEW Weltman, A J Dept of the Environment/Constructlon Industry Research and Information Association Piling Development Group report PGd, Sept 1977 , 38P Avail: CIRIA, 6, Storeys Gate, Lonlon SWIP 3AU, UK