Numerical Simulation for the Estimation of the Critical Length of Steel Pipe Jacking in Alluvial Ground

Abstract

In pipe jacking projects, there are several factors that could influence construction efficiency. Pipe dimensions are one of the main ones that affect the cost and safety of pipe jacking operations. However, the main factors influencing pipeline stability and the maximum allowable jacking length, which usually is called the critical jacking length, are rarely explored. In this paper, three-dimensional finite-element models were conducted to investigate the factors influencing the critical jacking length during pipe jacking, including pipe dimensions, soil specifications, buried depth, and overcut values using commercially available software. The critical jacking length of a steel pipe in an alluvial soil was estimated using the displacement control method, and the probable failure modes of steel pipes were determined. Two cases were selected to compare the pipeline stresses with field-measured data to validate the numerical results. The results suggested the developed model could estimate the critical jacking length based on the site characteristics and pipeline specifications, and a critical jacking length surface could be presented for each site based on the site properties, which would be beneficial to select required pipe segment dimensions at the preliminary design steps.