Abstract: The simplified reduction factor of shear modulus in the shear-compression zone of reinforced concrete beam was put forward and derived in the paper,and the simplified calculation method of nonlinear shear deformation was also brought forward.Nonlinear analysis of the spandrel deep beams reinforced concrete tube structure's can be carried out based on the three-fragment-line-element model.Finally,two examples were calculated and compared with test results,which shows that the presented method is reasonable.