96A 873089 Quiescent consolidation of phosphatic waste clays McVay, M; Townsend, F; Bloomquist, D J Geotech Engng Div ASCE Vl12, Nll, Not, 1986, P1033- 1049 A number of currently employed mathematical formulations used in modelling one dimensional quiescent consolidation of phosphatic waste clay ponds are reviewed. It is shown theoret- ically, as well as through an example, that the excess pore water pressure, void ratio, and ground settlements of the mod- els investigated are identical, with the only difference being in the selection of coordinate representation or dependent vari- ables. Correlation between centrifuge prediction of a proto- type pond and theory is presented with material parameters obtained from the laboratory. It is concluded that even though the effective stress versus void ratio representation is accepta- ble, the present laboratory techniques of finding void ratio versus permeability are deficient. Auth. 873090 Simple approach to the estimation of soil compaction parameters Al-Khafaji, A N Q J Engng Geol V20, N1, 1987, P15-30 The effects of both Atterberg limits and clay content on Proc- tor maximum dry density and optimum moisture content have been determined quantitatively for soils from four sites in Iraq. Empirical relations have been derived and charts are presented which make possible the estimation of potential optimum moisture content and maximum dry density for Proctor standard compaction, if liquid limit and clay content are known, and of less accurate estimation if only liquid limit is known. These charts are of great use in the construction of earthworks. 873091 Piezoprobe determined coefficient of consolidation Gupta, R C; Davidson, J L Soils Found V26, N3, Sept 1986, P12-22 A procedure is described for determining the in situ coefficient of consolidation by observing dissipation of excess pore pres- sures during piezometer probe penetration. It is based on curve matching between field dissipation plots and computer generated plots developed by means of a two dimensional uncoupled axisymmetrical consolidation dissipation of an ini- tial excess pore pressure distribution. Initial excess pore pres- sure is calculated from cavity expansion theory. Incremental computation allows for pore pressure dissipation during tip penetration. The procedure was applied to studies from three sites, and results showed reasonable agreement with labora- tory methods. 873092 Elasto-plastic uncoupled procedure for consolidation analysis and its comparison with coupled procedures Yamagami, T; Ueta, Y; Harumoto, S Proc 5th International Conference on Numerical Methods in Geomechanics, Nagoya, 1-5 April 1985 V1, P605-612. Publ Rotterdam: A. A. Balkema, 1985 An uncoupled procedure for solving elastic consolidation problems has been previously presented. The uncoupled pro- cedure is first extended to include the elasto-plastic behaviour of the soil skeleton. Ohta's elasto-plastic model is adopted to represent the soil behaviour. The significance of the newly pro- posed elasto-plastic uncoupled procedure is then made clear through various comparisons with two coupled procedures, Sandhu's and Christian's approaches. As a result, it is con- cluded that the uncoupled procedure may be of great practical usefulness. 873093 Consolidation analysis of the soft clay ground beneath large steel oil tank Zeng, G; Gong, X N Proc 5th International Conference on Numerical Methods in Geomechanics, Nagoya, 1-5 April 1985 V1, P613-620. Publ Rotterdam: A. A. Balkema, 1985 Equations of nonlinear and anisotropic elastic coefficients for normally consolidated (NC) clay have been developed. The parameters involved in the equations may be determined by the Ko consolidated drained axial compression and axial extension tests and unconfined compression tests on specimens cut in different directions. The effects of the following factors on the deformation behaviour of the soil have been taken into account: the initial stress state in the natural ground, stress state under loading, in compression or in extension, anisot- ropy, mean effective stress, and strength mobilization. A pro- cedure for analyzing the consolidation of soft clay ground by the finite element method, based on Biot's theory of consolida- tion, was established and applied to analyze the soft clay beneath two large oil tanks. Calculations and field observa- tions are in good agreement. Auth. 873094 New interpretation of oedometer consolidation test Asaoka, A; Matsuo, M; Ueda, K Proc 5th International Conference on Numerical Methods in Geomechanics, Nagoya, 1-5 April 1985 V1, P621-628. Publ Rotterdam: A. A. Balkema, 1985 A new formulation is presented for analyzing the laboratory data obtained in a conventional oedometer consolidation test. The first one or two predominant eigenvalues of consolidation are shown to be easily identified from usual observations in an oedometer test, and they are newly interpreted based on the theory of Terzaghi's one dimensional consolidation. The idea of the analysis is given in two ways for practical use; one is the graphical method, the advantage of which is its simplicity in determining the parameters of consolidation, and the other is an exact method. In the latter, those parameters are deter- mined taking the effect of skin friction between a ring and a confined soil specimen into consideration. In these two meth- ods, the required observation is only the time dependent behaviour of vertical displacement of the soil specimen and no measurement is necessary of excess pore water pressure. Auth. 873095 Consolidation behaviour of a single under-reamed anchor Pyrah, I C; Hird, C C; Tanaka, Y Proc 5th International Confeeence on Numerical Methods in Geomechanics, Nagoya, 1-5 April 1985 V1, P629-636. Publ Rotterdam: A. A. Balkema, 1985 The time dependent behaviour of a single under-reamed anchor, subjected to a constant load, has been examined both experimentally and theoretically. For the experimental work a 70mm diameter under-reamed resin anchor was formed in situ in a bed of kaolin prepared from a slurry. The anchor was loaded incrementally and for each constant load the anchor movement and pore water pressure, at some twenty locations around the anchor, were measured. For the theoretical study the anchor was idealised as a rigid circular plate and the con- solidation movements at constant load predicted using both the Terzaghi-Rendulic (uncoupled) and Biot (coupled) theo- ries. The Biot equations were solved using finite elements © 1987 Pergamon Journals Ltd. Reproduction not permitted