Calculation And Analysis Of Jacking Resistance Of Rectangular Pipe Jacking Construction

With the construction of urban integrated pipe corridors in full swing,rectangular pipe jacking construction has been widely used due to its high utilization rate,low cost-effectiveness and small impact on the surrounding environment.Combining with a rectangular pipe jacking project,the paper studies the calculation method of jacking resistance of pipe jacking construction through theoretical analysis,model test and numerical simulation.The main research contents and results are as follows:1.The contact relationship between the pipe jacking and the soil layer during the construction of the rectangular pipe jacking is analyzed.The various loads acting on the rectangular pipe section are discussed.The analysis of the Terzaghi theory,the Promojiyfakonkv arch theory and the soil column theory are carried out respectively.The formula for calculating the frictional resistance of the rectangular pipe section and the soil is given,and the calculation formula of the jacking resistance of the rectangular pipe in different theoretical conditions is derived.2.Using the similar model test,the variation of the earth pressure around the pipe jacking pipe and the stress and strain of the pipe jacking during the construction of the rectangular pipe jacking are analyzed.With the construction of the top pipe,the earth pressure value above the top pipe first increases and then decreases,and gradually stabilizes;and the strain on the four sides of the pipe first increases and then tends to be stable.Through the comparative analysis of the measured values of the model test and the calculated values of the theoretical formula,the rationality of the formula for the jacking resistance is verified.3.Combined with the actual engineering,the ABAQUS software was used for the simulation analysis.The change of the contact pressure and the frictional resistance between the soil and the pipe during the construction of the rectangular pipe was studied.Comparing the numerical simulation value with the theoretical calculation value,it is concluded that the jacking resistance can be calculated by using the theoretical frictional formula of the soil column under shallow burial conditions.