Search Results (2)

An innovative method is presented in this paper for the solution to the vehicle–bridge coupled vibration problem for highway bridges using the ANSYS software. By comparing the calculation results of this paper with those of the literature, the correctness and reliability of this method were verified. Taking a new structural bridge (composite truss bridge with partially concrete-filled rectangular steel tube members) as the engineering foundation, the vehicle-induced responses of the lower chords of the main truss were compared and analyzed in two states: partially concrete-filled and non-filled. Accordingly, the concept of the concrete filling coefficient was further developed, and the vehicle-induced responses of the new structural bridge and its impact coefficients were solved and analyzed for different concrete filling coefficients. The results showed that after partially filling the new structural bridge with concrete, the vertical dynamic stiffness of the bridge could be improved, the vehicle-induced response could be reduced, and the fatigue resistance could be increased. It is recommended that the concrete filling coefficient of the new structural bridge be within the range of 0.35 to 0.5. Under different concrete filling coefficients, the fitting results of the impact coefficient of the bridge submit to the extreme value distribution type-I, and the suggested value of the impact coefficient is 0.223 at a 95% assurance rate. For this new structural bridge, the impact coefficient values in Chinese specification are less than the suggested value of 0.223, which should be taken into account by bridge designers. Full article

In order to promote the development of bridge assembly technology and accelerate the application of rectangular steel-tube–concrete composite truss bridges, this study focuses on the Yellow River Diversion Jiqing Main Canal Bridge as the engineering example and conducts a numerical analysis of a rectangular steel-tube–concrete composite truss bridge. Based on the results of the analysis, structural optimization is achieved in three dimensions—structural design, construction methods, and force analysis—leading to the establishment of key design parameters for through-type ultra-high-performance rectangular steel-tube–concrete composite truss bridges. The results show that filling the hollow sections with ultra-high-strength concrete can significantly enhance the load-bearing capacity. Additionally, employing prestressed concrete components addresses the bending and tensile load capacity challenges of composite structures, thus maximizing the material strength advantages. The proposed preliminary design scheme incorporates prestressed PBL-reinforced tie rods filled with ultra-high-performance concrete with optimal design parameters, such as high span ratios, wide span ratios, and ideal segment lengths, are suggested to ensure that the strength, stiffness, and stability comply with relevant standards. While ensuring that the structure meets safety, applicability, and durability criteria, the preliminary design scheme reduces steel usage by 23.5%, concrete usage by 11.6%, and overall costs by 17.29% compared to the original design. The proposed design demonstrates distinct advantages over the original in terms of mechanical performance, construction efficiency, economic viability, and durability, highlighting its promising application potential. Full article