Design and behavior of super-long span cable-stayed bridge with CFRP cables and UHPC members

This paper proposes a cable-stayed bridge with carbon fiber-reinforced polymer (CFRP) cables and ultra-high performance concrete (UHPC) members and presents its design and structural behavior to analyze its feasibility with a super-long span. Based on the geometrical dimensions of a real cable-stayed bridge with a steel girder and cables in addition to a normal concrete (NC) pylon and main-span of 1088 m, a new counterpart cable-stayed bridge using CFRP cables and a UHPC girder and pylon was designed. The dimensions of the UHPC girder were quantified by the section stiffness, punching resistance, local stability, and shearing resistance. The cross-section sizes of the CFRP cables were determined by the principle of equivalent strength. The geometric and physical conditions of the UHPC pylon satisfied the principle of similarity theory. Using the finite element method, a comparative analysis of the mechanical behavior of two cable-stayed bridge schemes was conducted, specifically regarding the static behavior, global stability, aerostatic stability, dynamic mode, and seismic performance. The results indicated that the detailed design and superior performance of the CFRP and UHPC made it practical to form a highly efficient and durable concrete cable-stayed bridge system with CFRP cables and UHPC members. Moreover, these properties could enlarge the main-span of a concrete cable-stayed bridge to approximately 1000 m.