375A

cinders and decomposed granite, penetration tests and electri- cal resistance measurements were used to monitor dry density and water content during compaction. These techniques pro- vided rapid results for use in compaction control with the same accuracy as when JIS-approved methods are used.

936337 Comparison of rock correction methods for compaction of clayey soils Houston, S L; Walsh, K D J Geotech Engng Div ASCE Vl19, N4, April 1993, P763-778

Laboratory compaction tests were used to study the effect of 0-60% large aggregate on the maximum dry density and water content of clay. The tests were carried out primarily using ASTM D698 method D, with replacement of oversize aggre- gate. Maximum dry density obtained is compared to estimates of the rock correction equations of ASTM method 4718, USBR method 5515-89 and AASHTO procedure T224. Opti- mum water content from the tests is compared to that pre- dicted using rock correction equations in ASTM 4718. The significant differences found in maximum dry density values and their implications for construction control are discussed.

936338 Landfill restoration project Dobbie, K Quarry Manage May 1993, P37-39

The cap for the landfill at Sandsfield Gravel Company's Pit 11 was required to meet stringent regulations of the NRA and local planning authorities. A minimum of lm of clay with specified maximum permeability was necessary. Local clay deposits were exposed and shown to be capable of meeting specifications in laboratory tests. The nuclear density meter was chosen for simple and rapid in situ monitoring of place- ment density. Placement was mainly by bulldozer and vibratory roller.

936339 Undrained bearing capacity of clay with sand piles Asaoka, A; Matsuo, M; Kodaka, T Proc Ninth Asian Regional Conference on Soil Mechanics and Foundation Engineering, Bangkok, 9-13 December 1991 V1, P467-470. Publ Thailand. Southeast Asian Geotechnical Society, 1991

Bearing capacity of soft clay ground containing sand compac- tion piles has been examined using a limit equilibrium analysis which makes distinction between undrained and drained con- ditions for the sand. This yields a new interpretation for the mechanism of stress concentration in sand piles at the limit state. Sand replacement ratios from 30-70% are considered to obtain data to calculate required length of the sand piles. The analysis is applied to results of a field loading test of improved ground with a low sand replacement ratio.

936340 Behaviour of stone column foundation Guo, W D; Qian, H J Proc Ninth Asian Regional Conference on Soil Mechanics and Foundation Engineering, Bangkok, 9-13 December 1991 V1, P479-482. Publ Thailand." Southeast Asian Geotechnical Society, 1991

Research on the bearing capacity and settlement of a founda- tion reinforced by stone columns (granular piles) is presented. Formulae for stress concentration ratio and settlement reduc- tion factor were deduced and verified by extensive field loading tests plus triaxial tests. Bearing capacity has been investigated for general shear failure and bulging failure, and field trials

used to validate the formulae obtained. A case study of a building on saturated loess reinforced by stone columns is used as an illustrative example of application of this work.

936341 Mechanism and application of grouting in soft clay Hou, X Y; Bai, Y Proc Ninth Asian Regional Conference on Soil Mechanics and Foundation Engineering, Bangkok, 9-13 December 1991 VI, P487-490. Publ Thailand: Southeast Asian Geotechnical Society, 1991

The application of fracture grouting, where a cement ball is formed and compacts the surrounding soil, has been examined in laboratory tests. The four stages are described: bulging, fracturing, passive earth pressure failure, and solid flling. Compaction was monitored via resistivity sensors in the soil mass. Two case histories of fracture grouting application are illustrated: grouting the bottom of a deep excavation between diaphragm walls and grouting applied to open caisson correction.

Ground freezing

See: 936265

Surface Structures

Geological factors of importance in surface structures

See also: 936421

936342 Tectonic causes of landslides Alexander, D; Formichi, R Earth Surf Process Land V18, N4, June 1993, P311-338

Relations between mass movements and tectonic lineaments in the Pliocene sand and clay terrains of Montepulciano, central Italy, have been examined. Remote imaging shows six families of lineaments. Morphological phenomena such as retrogres- sive slumps, drainage density, and slope angle have been related to orientation, location, and density of the lineaments. Stereographic and statistical analyses indicate close correla- tion between slump movement and directions and spatial con- centrations of the lineaments.

Base courses and pavements

See also." 936211

936343 Shakedown in layered pavements under moving surface loads Collins, I F; Wang, A P; Saunders, L R Int J Num Anal Meth Geomech V17, N3, March 1993, P165- 174

Permanent and recoverable deformations of pavements of lay- ers of different granular materials subject to cyclic loading are examined. The upper bound kinetic shakedown theorem is used to obtain the load above which deformation will be plastic until failure conditions are reached, the critical shake- down load. Influences of loading distribution, interaction

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