Second Order Effect Analysis of Main Tower of Nanchang Hongzhou Bridge
The main bridge of Hongzhou Bridge in Nanchang is a steel-concrete composite beam double tower self anchored suspension bridge with a span of(50+120+252+120+50)m and a semi-floating system.The main tower is a portal bridge tower with a 昌-shaped style,and the nominal tower height above the pedestal is 116.291 m.To study the second-order effect and ultimate bearing capacity of the main tower of Hongzhou Bridge under compression bending,an open source finite element software OpenSees is used to establish a nonlinear beam column element model of the main tower.Considering geometric and material nonlinearity,calculate the eccentricity increase coefficient and ultimate bearing capacity of the main tower under design load,and analyze the ultimate bearing capacity of the main tower under different reinforcement conditions.Propose an optimized reinforcement scheme and apply it to engineering implementation.Furthermore,the article explores the rationality of calculating the eccentricity increase coefficient in current standards and proposes a method for calculating the eccentricity increase coefficient applicable to large compression bending members.Compared with the original standard formula,the algorithm proposed in the article has a higher degree of agreement with the finite element simulation results,and can be used for the design of large compression bending components such as super high bridge towers.
cable-stayed bridgebridge towerstabilitysecond-order effectfinite element analysisequation