The pore pressure generation and deformation of overconsolidated soft marine clay considering initial static shear effect
Ming Dai, Lin Guo, Mingfeng Li, Tian Jin
Abstract
In coastal engineering, the cyclic loading caused by traffic, wind, and waves is superimposed on the initial static shear stress in certain infrastructures such as embankments. In some cases, a portion of the subgrade soil is overconsolidated owing to the process of surcharge preloading. Therefore, it is of great practical relevance to study the effects of the initial static shear on the undrained cyclic response of overconsolidated soft marine clay. In this study, a series of monotonic and cyclic triaxial tests were conducted on soft marine clay with a broad range of initial static shear stress ratios (SSRs) and overconsolidation ratios (OCRs) to investigate the pore water pressure response and deformation characteristics. Several useful conclusions were drawn. Importantly, the development and maximum number of cycles of the permanent pore water pressure were found to depend on the SSR and OCR values. Based on the shakedown theory and typical stress–strain relationship, the development of the permanent axial strain was classified into three ranges.