连续梁桥上无缝道岔伸缩力与位移计算

Calculation of Longitudinal Force and Displacement of Seamless Turnout on Continuous Beam Bridge

将钢轨和梁体视为杆单元,轨枕视为梁单元,扣件阻力、道床阻力和桥墩刚度视为弹簧单元,建立了计算连续梁桥上无缝道岔伸缩力与位移的有限元力学模型,根据变分原理和“对号入座”法则建立了模型求解的非线性方程组,分析了道岔设计参数对桥上无缝道岔伸缩力和位移的影响。研究结果表明:伸缩调节器布置在道岔的后端,连续梁固定墩的纵向力可降低43.2%;增加连续梁固定墩纵向刚度有利于减小钢轨位移;连续梁固定支座的位置对系统的受力与变形有双重影响,实际设计时应综合考虑。

Rail and beam were regarded as bar elements, sleeper was regarded as beam element, fastening resistance, ballast resistance and pier stiffness were considered as spring elements, a finite element mechanics model was proposed to calculate the longitudinal force and displacement of seamless turnout on continuous beam bridge, the nonlinear equations of the model were established by variational principle and ＂set-in-right-position＂ rule, the influences of turnout design parameters on the longitudinal force and displacement were analyzed. Calculation result shows that the longitudinal force on the fixed pier of continuous beam decreases by 43.2 ~/0 when the expansion joints are laid in the back of seamless turnouts, the longitudinal stiffness increase of the fixed pier leads to the decrease of rail displacement, the fixed support location of continuous beam should be taken into consideration in the system design because it influences the longitudinal force and displacement of the system. 2 tabs, 12 figs, 8 refs.