Rapid Evaluation of Load-Bearing Capacity of π-Shaped Steel-Concrete Composite Continuous Rigid Frame Bridges Based on Quasi-Static Influence Line

As a new bridge structure type, it is crucial to quickly and accurately evaluate the safety of π-shaped steel-concrete composite continuous rigid frame bridges in order to ensure the safety of bridge cluster structures in the long-term operation stage and emergency situations. Based on quasi-static influence line technology, this paper proposes a rapid evaluation method of load-bearing capacity of π-shaped steel-concrete composite continuous rigid frame bridges. First, a theoretical quasi-static displacement influence line calculation method is established. Then, based on advanced sensing technology, an actual quasi-static influence line inversion method is proposed. Next, we construct the bridge structure load-bearing capacity evaluation index which can fully consider the detection information. Finally, the performance of the proposed method is verified by a case study with the use of theoretical derivation and numerical simulation. The result shows that the method proposed in this paper can realize the rapid evaluation of load-bearing capacity of π-shaped steel-concrete composite continuous rigid frame bridges subjected to short-term traffic interruption reliably.