列车制动作用下铁路简支梁桥桥墩受力试验研究

基于一铁路简支梁桥在25 t轴重列车制动作用下的受力试验测试,分析了制动过程中列车加速度,推算出墩身混凝土弹性模量、墩顶纵向刚度,求得列车制动下的墩顶挠曲力、制动力,并将实测结果与有限元分析结果进行了对比分析。研究结果表明:列车制动加速度在-0.016g左右,墩身混凝土弹性模量为设计值的1.20倍左右,墩顶制动力实测值的变化规律与理论值的基本一致。由于试验实测加速度较小,故根据本次试验结果推算出在列车更大制动力率下该桥的纵向受力,桥墩纵向受力满足设计及运营要求。

Experimental Research About Forces on Piers of a Railway Simply-supported Girder Bridge Under Train Braking Load

Based on the experimental analysis of a railway simply-supported girder bridge under 25 t train braking load,the train acceleration during braking process was analyzed.The concrete elasticity modulus and the longitudinal stiffness of the pier top were calculated.The bending force and the braking force at the pier top due to the train braking load were studied.The measured data were compared with the analysis results using f inite element method.The results show that the train braking acceleration is about -0.016 g ,the concrete elasticity modulus is about 1.2 times of the design value,and the tendency of the measured values of braking force on pier top is almost the same as the theoretical values.Because the measured acceleration is relatively small,the bridge s longitudual forces under higher train braking force ratio waere deduced according to the test results.The results show that the longitudinal force of the bridge piers can meet the design and operation requirements.