Tokyo Metropolitan Government has developed to apply the shield construction method with four-segmented three-hinged structure, which is suitable for construction of the main and the branch lines of Sewage re-construction plan, in the field. This segment is different from the conventional one with bolted joints. It has the hinge coupler joint which cannot resist tensile forces. Usually analysis for internal pressure is omitted for sewage tunnels. However, in this study loading tests for internal water pressure were carried out to confirm safety of the hinged structure in the case of unexpected level of rainfall and unbalanced loading conditions caused by construction in vicinity. The result of the loading tests confirms safety and watertightness of the tunnel in both cases