Longitudinal Progression of Burst Head during Pipe Bursting

Abstract

Axisymmetric finite element analysis is used to model the forward movement of the burst head along the pipe axis during static pipe bursting. The modeling procedures are described, including treatment of the mixed boundary condition at the interface between the bursting head and the surrounding material, along which radial displacements are imposed to match the cavity expansion as the rigid burst head displaces the surrounding ground, and friction is also modeled. Calculations are reported for the four pipe bursting configurations considered in an earlier laboratory study. Comparisons of calculated and measured values of pulling force reveal that the new finite element procedure provides effective measurements of the resistance of the burst head to forward progression and the total force required to pull the bursting head and new pipe through the old pipe system. The numerical procedure could be used in future studies to estimate pulling force requirements for specific projects, considering the burial depth, soil material, degree of pipe upsize, and specific geometry of the pipe bursting head.