Abstract

The jacked-in pile method provides a substitute procedure that permits the installation of pre-formed piles with negligible vibration in a noiseless manner, thereby reducing noise impacts in marine and urban environments. This research was carried out by using a small-scale physical modelling approach to examine the movement of soil during pile installation. The model soil was formulated from a mix of amorphous silica and mineral oils; the resulting mixture was subjected to consolidation in a transparent chamber. The model pile was driven vertically down the mid-point of the soil model at different vertical speeds using a strain control device. The array of soil displacement dispersal was obtained by utilising the close-range photogrammetry and particle image velocimetry techniques. The deformation of soil during pile installation was found to decrease with progressive increase of the penetration rate. This result can be employed in the assessment of the disturbance effects of pile installation on underground services and archaeological relics beneath the ground in both urban and marine environments.

摘要

顶桩法提供了一种替代程序，允许以无噪音的方式安装振动可忽略不计的预制桩，从而减少对海洋和城市环境的噪音影响。这项研究是通过使用小规模的物理建模方法来检查桩安装过程中土壤的运动的。模型土壤是由无定形二氧化硅和矿物油的混合物配制而成的；所得混合物在透明室中固结。使用应变控制装置以不同的垂直速度将模型桩沿土壤模型的中点垂直向下驱动。利用近距离摄影测量和颗粒图像测速技术获得了土壤位移分散的阵列。发现桩的安装过程中土壤的变形随着渗透速率的逐渐增加而减小。该结果可用于评估桩安装对城市和海洋环境中的地下服务和地下考古文物的干扰效果。