Experimental study on performance of joints between arch ribs and web members of steel-UHPC composite truss arch bridge
Shao Xudong1,2 Chen Yubao1,2 He Guang1,2 Zhao Xudong1,2 Wang Yang1,2
1. School of Civil Engineering, Hunan University, Changsha 410082, China;
2. Key Laboratory for Wind and Bridge Engineering of Hunan Province, Hunan University, Changsha 410082, China
Abstract：The proposal of the steel-UHPC composite truss arch bridge is expected to solve the problems of high cost and difficult construction of very-long-span arch bridges. The mechanical performance of the key joints between the arch ribs and web members in a 1000m long steel-UHPC composite truss arch bridge was studied. The calculation showed that the axial forces in both the tension and compression web members were over 10,000kN under the fundamental combination of loads. In order to ensure a firm combination of steel and UHPC at the joint, a new specific joint structure with the steel connector which has different shear connectors between the UHPC box arch ribs and steel web members is proposed via structural performance analysis and optimization study for the joint. A 1/5 scale test model was fabricated for the most unfavorable joint, which ignores the contribution of the bottom plate and webs in the box arch rib to the joint’s mechanical performance. Then, a planar three-directional loading test and a pull-out test were carried out. The test results showed that the failure mode of the joint structure in the planar three-directional loading test was characterized by cracking in one side and crushing in the other side while the composite effect was preserved well. Besides, the failure mode of the joint structure in the pull-out test was characterized by the shear failure in the UHPC arch rib along the outline of the steel connector. The ultimate load of the joint in the planar three-directional loading test was 2.72 times the design load, and the nominal cracking strength of the UHPC arch rib was 13.36 MPa, which is 1.85 times the design stress, indicating that the bearing capacity and crack resistance of the joint can meet the design requirements. The shear and pull-out resistance of the joint structure along the interface between the steel connector and UHPC arch rib can meet the requirements under the serviceability limit state and ultimate limit state.
邵旭东 陈玉宝 何广 赵旭东 王洋. 钢-UHPC组合桁式拱桥拱肋与腹杆节点性能试验研究[J]. 土木工程学报, 2022, 55(5): 54-66.
Shao Xudong Chen Yubao He Guang Zhao Xudong Wang Yang. Experimental study on performance of joints between arch ribs and web members of steel-UHPC composite truss arch bridge. 土木工程学报, 2022, 55(5): 54-66.
