Analytical solution for predicting ground deformation associated with pipe jacking

Pipe jacking plays a vital role in project execution by providing an economical, practical, and environmentally responsible approach to installing buried pipeline systems. Effectively calculating ground movement is an important preconstruction consideration and can present a challenge to the pipe-jacking industry. Four main factors that contribute to potential ground movement during pipe jacking are discussed in this paper: (1) soil loss; (2) fluid pressure; (3) friction between the pipe and soil; and (4) jacking force at the cutting head. A new model based on the Mindlin Solution and considering these four factors is presented. In the model, a new solution for predicting ground movement caused by soil loss is proposed and a theoretical solution of ground movement caused by fluid pressure is demonstrated. Data from the Guan River Pipe Jacking project in Jiangsu Province, China were used for comparison with established predictive models. The research results show that surface movement is not uniform along the length of an installation. The model developed in this paper effectively predicts surface movement during pipe jacking and more-accurately reflects field data than existing models.