Performance evaluation of lattice girder and significance of quality control

It has been reported that lattice girders fail due to inadequate steel members. An experimental analysis is herein conducted using material and structural tests to determine the behavior of lattice girders made of B500B and SS400, two representative steel materials. A numerical analysis is also carried out to evaluate the performance of lattice girder in a tunnel. Both the experimental and numerical study indicated that the use of inadequate steel members results in a significant reduction in the working load and can also affect the overall structural stability of the tunnel. Therefore, quality control for lattice girders is of great importance. A review of the quality control systems for lattice girders reveals it to be desirable to introduce an on-site testing method to identify the adequacy of a steel member in the field. Thus, the portable indentation test is suggested as an on-site quality control test for a lattice girder.