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Prediction of compressibility of overconsolidated uncemented soils. Technical note
182A 865097 Application of multivariate statistics and saturation extract data to identify dispersive clay soils Craft, D Geotech Test J I/9. NI. March 1986, P34-3" By substituting selected pore water data (chemical and electrical properties) into derived discriminant classification functions, it was possible to classify soils from a construction site as dispersive or non-dispersive. The discriminant functions were derived using discriminant analysis, a multivariate statistical technique, on a 28 sample data set. This method was used after failure of the pore water chemical method of Sherard et al (1976). The discriminant analysis merely identifies variables having the ability to differentiate between dispersive and nondispersive soils in this case. The discriminant functions should not be applied generally. 865098 Natural compaction of sands as a function of their genesis Bazynski, J: Frankowski, Z lnt Assoc Engng Geol Bull N32. Dec 1985. P3-10 Results of static-dynamic probing in sandy soils of varying genesis and age are discussed. On the basis of site investigations, similarity was found in the natural compaction of these sediments. It was demonstrated that the accuracy and reproducibility of test data from the cone penetration test (CPT) and light dynamic probing (DPL) were suitably high. The effect of drainage on dynamic probing rcst.hs was discussed. Methods for the graphical analysis of static-dynamic probing results arc presented from the viewpoint of the needs of the building industry'. 865099 Prediction of compressibility of overconsolidated uncemented soils. Technical note Nagaraj, T S; Srinivasa Murthy, B R J Geotech Engng Div ASCE VII2. N4. April 19,~6. P484-488 In this investigation, an attempt is made to extend the physical model to define the compressibility of stress-dependent overconsolidated unccmented soils. 865100 Consolidation of alluvial clay under repeated loading Fujwara. H; Yamanouchi. T; Yasuhara. K: Ue. S Soils Found 1"25. N3. Sept 1985. P19-30 Remouldcd saturated cohesive soil samples wcrc subjected to static and repeated loading consolidation tests. Samples were more compressible under repeated loading conditions, the difference in settlement seemingly due to secondary consolidation and change in soil particle structures. An attempt is made to interpret the consolidation of clay under repeated loading so as to be able to predict the effects of total load, loading period, load increment ratio and number of load cycles on settlement of foundations. A simplified settlement calculation is presented for the case of an oil tank foundation on clay. 865101 Construction of a highway on a sanitary landfill and its longterm performance Burlingame. M J Trans Res Rec NI031. 1985. P34-40 Short and long term settlements of the Interstate 85 roadway. New Jersey. USA. which was constructed on sanitary landfill (compacted refuse) are presented and compared with published data from other similar sites. Stabilisation was by placing a pad of granular fill between the landfill and the proposed
pavement and surcharging. Measured settlements are compared to those based on formulae developed on the basis of behaviour of similar fills at other sites. These equations gave conservative predictions of measured settlements. Long term settlements appear to be greatly reduced if a surcharge greater than that minimally required for stabilisation is used {oversurcharging). Interstate 85 showed no damage and minimal differential settlement. 865 ! 02 Rational approach to predict swelling soil behaviour Nagaraj, T S; Srinivasa Murthy, B R Trans Res Rec N1032, 1985. PI-7 A phenomenological model, based on truncated diffuse double layer theory, has been developed to predict the swelling pressure of soils. The swelling behaviour is described in terms of swelling pressure, swollen void ratio, preconsolidation pressure and the slope of the line joining the present state to preconsolidation pressure. There are four equations in terms of initial void ratio, void ratio at liquid limit water content, and effective overburden pressure. Computed swelling pressures are demonstrated in graphic form, and the validity of the approach is substantiated by the close agreement between predictions and field observations. 865103 Measurement of swelling pressure in the laboratory and in situ Ofcr, Z: Blight, G E Trans Res Rec NI032. I985, P15-22 Some commonly used laboratory and in situ methods for the determination and prediction of swelling pressure arc reviewed. Two instruments developed in South Africa, the lateral soil pressure ring and the in situ soil pressure probe, arc dcscribcd and test results are compared with field loading test measurements. It is concluded that if sampling disturbance, size effects, sampling selectivity, and simulation of actual site conditions are accounted for, laboratory and field results agree well. 865104 Prediction of swelling pressure and factors affecting the swell behaviour of an expansive soil Mowafy. Y M; Bauer, G E Trans Res Rec N1032. 1985. P23-28 Soil friction and the non-uniform distribution of water during saturation are the main sources of error when determining swelling properties of expansive soils. Various techniques to minimise soil-confining ring friction in the oedomctcr test were tried, and their merits and backgrounds are discussed. After experimental testing of 28 soil specimens, a semi-empirical equation was deduced to describe swelling pressure in terms of initial dry density, initial water content and clay content of the soil. This equation is compared to other methods of predicting swelling pressures. The proposed equation may be used as a design guide to predict swelling pressure for the soil studied. 865105 Treatment of expansive soils: a laboratory study Mowafy, Y M: Bauer, G E; Sakeb, F H Trans Res Rec N1032, 1985, P34-39 Three techniques to reduce the amount of swelling and the associated swelling pressure for expansive soils were evaluated in the laboratory. They were: variation of the initial water content before compaction: increasing the proportion of the sand content: and altering the salinity of the pore fluid. All were to some extent successful, and could be used together under favourable circumstances.
~ 1986 Pergamon Journals Ltd. Reproduction not permitted
pavement and surcharging. Measured settlements are compared to those based on formulae developed on the basis of behaviour of similar fills at other sites. These equations gave conservative predictions of measured settlements. Long term settlements appear to be greatly reduced if a surcharge greater than that minimally required for stabilisation is used {oversurcharging). Interstate 85 showed no damage and minimal differential settlement. 865 ! 02 Rational approach to predict swelling soil behaviour Nagaraj, T S; Srinivasa Murthy, B R Trans Res Rec N1032, 1985. PI-7 A phenomenological model, based on truncated diffuse double layer theory, has been developed to predict the swelling pressure of soils. The swelling behaviour is described in terms of swelling pressure, swollen void ratio, preconsolidation pressure and the slope of the line joining the present state to preconsolidation pressure. There are four equations in terms of initial void ratio, void ratio at liquid limit water content, and effective overburden pressure. Computed swelling pressures are demonstrated in graphic form, and the validity of the approach is substantiated by the close agreement between predictions and field observations. 865103 Measurement of swelling pressure in the laboratory and in situ Ofcr, Z: Blight, G E Trans Res Rec NI032. I985, P15-22 Some commonly used laboratory and in situ methods for the determination and prediction of swelling pressure arc reviewed. Two instruments developed in South Africa, the lateral soil pressure ring and the in situ soil pressure probe, arc dcscribcd and test results are compared with field loading test measurements. It is concluded that if sampling disturbance, size effects, sampling selectivity, and simulation of actual site conditions are accounted for, laboratory and field results agree well. 865104 Prediction of swelling pressure and factors affecting the swell behaviour of an expansive soil Mowafy. Y M; Bauer, G E Trans Res Rec N1032. 1985. P23-28 Soil friction and the non-uniform distribution of water during saturation are the main sources of error when determining swelling properties of expansive soils. Various techniques to minimise soil-confining ring friction in the oedomctcr test were tried, and their merits and backgrounds are discussed. After experimental testing of 28 soil specimens, a semi-empirical equation was deduced to describe swelling pressure in terms of initial dry density, initial water content and clay content of the soil. This equation is compared to other methods of predicting swelling pressures. The proposed equation may be used as a design guide to predict swelling pressure for the soil studied. 865105 Treatment of expansive soils: a laboratory study Mowafy, Y M: Bauer, G E; Sakeb, F H Trans Res Rec N1032, 1985, P34-39 Three techniques to reduce the amount of swelling and the associated swelling pressure for expansive soils were evaluated in the laboratory. They were: variation of the initial water content before compaction: increasing the proportion of the sand content: and altering the salinity of the pore fluid. All were to some extent successful, and could be used together under favourable circumstances.
~ 1986 Pergamon Journals Ltd. Reproduction not permitted