In order to improve the bearing capacity and stiffness of shield tunnel lining segment, corrugated steel is used to strengthen the shield lining segment. In this paper, fullscale tests are conducted on two segments strengthened by corrugated steel and one segment without strengthening to study the loading progress, failure mode and strengthening mechanism and evaluate the strengthening effect. The test results show that: (1) The corrugated steel is an effective strengthening material which can effectively improve the ultimate bending capacity and stiffness. (2) The failure mode of the strengthened segment is shear failure. (3) Shear stress and radial peeling stress exist on the interface between corrugated steel and segment concrete, and it is necessary to carry out effective countermeasures.