连续小箱梁桥虚拟横梁刚度模拟研究

Study on Simulation of Virtual Beam Stiffness of Continuous Small Box Girder Bridge

为了真实反映组合小箱梁桥的空间受力情况,以某3×30 m连续小箱梁桥为例,利用有限元软件Midas/Civil分别建立实体模型和梁格模型。用近似理论方法和有限元方法分析得出汽车荷载横向分布,以计算结果相互逼近为原则,用5种等效方法模拟并重点研究梁格模型中虚拟横梁刚度,推荐一种较合理的虚拟横梁刚度等效方法。结果表明:采用方法 3(梁端刚域法)的梁格模型中汽车荷载横向分布情况,与近似理论计算和实体模型分析的结果均相近,且介于两者之间。

In order to truly reflect spatial force of combined small box girder bridge, finite element softwareMidas / Civil was used to respectively set up solid model and beam lattice model based on an example of a3伊30m continuous box girder bridge. Then the approximate theoretical method and finite element methodwere used to analyze the transverse distribution of vehicle load. With the principle of mutual approximationof the calculation results, five kinds of equivalent methods were used to simulate and the rigidity of thevirtual beam in the beam lattice model was focused on. A more reasonable equivalent stiffness method ofthe virtual beam was proposed. The results have showed that the transverse distribution of vehicle load inthe beam lattice model using method 3 （beam end rigid domain method） is similar to that of approximatetheoretical calculation and solid model analysis, and lies between the two.