A Simplified Approach for Estimating Settlement of Soft Clay under Vacuum Consolidation

다국어 초록 (Multilingual Abstract)

In general, the ground improvement by Prefabricated Vertical Drains (PVD) consolidation involves a high magnitude of settlement, which results in a change in the consolidation characteristic of the soil during the process of consolidation. Under such circumstances, the consolidation problem must be treated as a large strain problem. The large strain 3-Dimensional consolidation analysis requires a large number of parameters, making it difficult for practicing engineers to carry out such analysis for a practical application. This paper aims to provide a simplified method for estimation of settlement during 3D vacuum consolidation using a single parameter, the coefficient of horizontal Consolidation (Ch). For this, the variation in Ch during the 3D consolidation was backcalculated using Hansbo’s method from a series of large-scale 3D vacuum consolidation tests carried on reconstituted marine clay. As the varying Ch cannot be employed in available analytical models, a simplified finite element analysis is presented to employ varying Ch. The estimated settlement was further compared with settlement obtained utilizing constant Ch, by trial and error method. The paper also demonstrates a potential advantage of the proposed method that the variation in Ch can also be determined from 3D consolidation carried out previously for similar strata, as it requires only basic data, which are usually available.

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