Predicting Soil Expansion Force during Static Pipe Bursting Using Cavity Expansion Solutions

Abstract

The prediction of total pull force is critical for static pipe-bursting installation. As a major component of the total pull force, soil expansion prediction is also important; however, there are currently limited methods available for such prediction. In this paper, three cavity expansion solutions were used to predict soil expansion pressure acting upon the expander (bursting head) during static pipe bursting. The determined soil expansion pressure was then used to calculate the expansion force required for pipe bursting with or without consideration of the soil collapse. Calculated results were then compared with those from laboratory pipe-bursting experiments to evaluate the feasibility of the calculation methods. The comparison indicated that the large-strain cavity expansion solution reasonably predicted the soil expansion force. The small-strain solution significantly overestimated the soil expansion force. Additionally, considering soil collapse during pipe bursting resulted in a remarkably higher calculated expansion force than that without consideration; in this study, the soil collapse effect should be taken into account because a sandy soil was used in the laboratory experiments.