Influence of Internal Force in the Rectangular Shaft for the Pipe Jacking with a Reserved Hole

The launching shaft or the receiving shaft are the most critical structures in the pipe jacking project, and circular holes of different sizes are needed on the shaft wall for the pipes to enter and exit. The setting of the holes affects the stress of the shaft structure. Relying on a DN3500 inner diameter electrical power pipe jacking project in Xi'an, the influence law of the shaft wall opening constructed by the open excavation method on the shaft structure was studied using the finite element method. The results were compared with the open caisson under the same conditions. The internal force calculation results of the design are compared, and the internal force variation law before and after the open excavation of the shaft with different methods was obtained. The corresponding structure optimization design suggestions are put forward and provide reference for the design and analysis of related projects.