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To solve the deformation control problems caused by underpass construction of tunnel, the project of shield tunneling of Zhengzhou Metro Line 4, undercrossing closely the existing traffic pipe- jacking tunnels, is studied. Numerical simulation combined with field monitoring is used to reveal the deformation law of the existing jacking tunnels during shield tunnel construction. Based on numerical simulation results, settlement control standard of the pipe-jacking tunnel, the allowable joint opening value of pipe-jacking joints and the minimum allowable radius of curvature of the structural line are established. Then the correctness of the numerical calculation results and the feasibility of setting method of the settlement control standard are confirmed by on-site monitoring. The main conclusions are as follows:( 1 ) During the process of the two shield tunnels crossing the pipe-jacking tunnels at an intersection angle of 37°, the vertical settlement curves of the upper pipe-jacking tunnels present asymmetric characteristics, and the settlement curves of the tunnels show some translation and deflection. (2) Compared with the joint opening control standard, the settlement control requirements based on allowable additional curvature of pipe jacking tunnel deformation are relatively stricter. It is suggested that the maximum allowable settlement value of the jacking tunnel under construction disturbance should be 27mm. [ABSTRACT FROM AUTHOR]