7th Regional African Conference on Soil Mechanics, volume 1

Techincal Editors: M.D. Gidigasu, A.A. Hammond, J.O. Gogo, all Building & Road Research Institute, Kumasi, Ghana.

• Preface 1 Engineering geology and the geotechnical properties of problem soils; Engineering geology in the assessment of tunnelling conditions for an urban sewer tunnel; The search for road building materials in the sands of Owambo; The location and engineering properties of volcanic cinder gravels in Ethiopia; Engineering properties of a delta deposit of Lake Malawi; Geotechnical properties of West and North African continental shelf sediments; Mechanical properties of the Cretaceous sediments of the Natal coast; Engineering properties of aeolian Kalahari sands; Geotechnical properties of a deep organic clay stratum underlying Lagos area of Nigeria; Residual shear strength of tropical soils; Variability of geotechnical properties of subgrade soils in a residual profile over phyllite; The use of the chemical and physio chemical properties of laterites in their identification; Mining waste evaluation as highway material; V 2 Field and laboratory testing of problem soils; Shear testing of some fissured clays; The determination of dump rock properties in field tests; Pressure meter testing of weathered Karroo siltstone; Prediction of soil heave from suction measurements; The use of cone penetrometers for the determination of the liquid limits of soils of low Plasticity; Variability of particle size distribution of a red mud with different pretest preparation Methods; Particle breakdown in pavement layers during compaction; The aggregate crushing value and the 10 per cent fines aggregate crushing test compared; An investigation of the slake durability test for mudrocks used in road construction; Durability testing of and specifications for degrading Dwyka tillite in southern Africa; Measurement of the specific surface of a problem material; An evaluation test on Utica shale; Relation between CBR and 'Static’ modulus of deformation of stabilized lateritic soils; 3 Foundations in problem soils. Broad regional evaluation of expansive soil conditions for shallow foundations in Ghana; Earthworks and foundations on recently deposited organic soils in the Lagos area; The failure of foundations in coastal plains sands of Nigeria; Some foundation design problems in Sokoto area of North Western Nigeria; A com parison of existing methods for the design of stiffen ed raft foundations on expansive Soils; The rational design of raft foundations for houses on heaving soil; Severe heaving of a block of flats near Kimberley; Vl; Damage to a building founded on expansive slag fill; 4 Problem soils in pavement construction. The importance of strength criterion in selecting some residual gravels for pavement Construction; Soil compaction at low moisture content - Field trials in Sudan; Compaction for collapsing sand roadbeds; Simulation of salt damage to roads with laboratory model experiments; Geotechnical evaluation of natural and treated black cotton clay for possible use for low cost pavements; Measuring the performance of unsealed road surfaces in Ghana; Interpretation of deflection measurements on poor roads; An operational management aid for low cost road maintenance; An appropriate serviceability rating method for low cost paved roads 5 Problem soils in dams and embankments, and the stability o f slopes; Design and monitoring of an embankment on alluvium; Interesting features of a coal dump-ash dam at Kilbarchan colliery; Filtration: An application of a statistical approach to filters and filter fabrics; Landslides caused by liquefaction of pumice gravel in Tukuyu district, Tanzania; The identification and use of dispersive soils at Elandsjagt Dam South Africa; Problèmes de stabilité dans quelques roches altérées du Précambrien du Congo; General topics, Notes on the potential u se of crushed l térite rock for concrete aggregate; Optimum utilization of available engineering data: A case for data bank in soil analysis.