STUDY OF METHODS OF PREDICTING PRECONSOLIDATION OF SOIL AND TIME RATE

Abstract

For the design of any structure generally the two aspects are the most important viz the hearing capacity and settlement. In most cases the settlement governs the design requiring lesser bearing pressure to be used, The settlement of the soil is governed by the type, ,-is well as in Case of clays whether the same is pre consolidated or normally cons Dlieated. The settlement is less in preconso-lidated clays and the amount can be found out ccrrectly only if the true preconsolidation load could be computed. There are three methods of finding preconsolidation load viz the Casegran-de's method, the Burmister's method and the Schmertman's method. In the present study the .samples of Kaolin and Bentonite were prepared in preconsolidation condition in the laboratory simulating the fiel,. conditions. The samples were initially prepared at liquidd limit before preconsolidatiori. The computa-tions were made, of the preconsolidation load by all the above; methods and were analysed with respect to actual values of ore-consolidation load. A method has been propose:; which computes the values closer to the actual ones, and the sample for trial in the Schmertmann's method has been modified and narrowed' to a much smaller range. It is not only the settlement hut also the time rate which may govern the design and the type of the structure. For time rate Terzaghi's consolidation theory comes to help as and the methods have been originated on the same basis viz leg fitting, square root fitting, Scott, Fox, slope fitting, and U6 point method. The results of the cons oliThti