关键词: 饱和软黏土, 足尺静压桩, 挤土效应, 侧向位移, 地面隆起, 孔隙压力

Abstract:

Soil compacting effect of jacked-in pile in the saturated soft clay is a topic of concern in the geotechnical engineering. Monitoring laws of lateral displacement of soil, pore pressure and land upheaval during pile-sinking is a project that a lot of researchers hope to implement. In this research, three full scale jacked-in piles are penetrated into the saturated soft clay and mostly studied by monitoring the law of lateral displacement with depth and radial distance to pile-sinking, the law of land upheaval with depth of penetration and radial distance to pile-sinking, and the law of pore pressure with penetration depth and time. Characteristics of maximum excess pore water pressure with radial distance and depth are also analyzed. From this test results, it is obtained that the maximum lateral displacement occurs at a depth of about 0.75L; land upheaval build up rapidly and reach the maximum when the pile tip arrive at depth of about 6 m; and the increment of excess pore water pressure reaches the maximum when the pile tip arrive at the piezometer level; while the maximum excess pore pressure presents a hysteresis quality with radial distance.

Key words: saturated soft clay, full scale jacked-in pile, soil compacting effect, lateral displacement, land upheaval, pore pressure