山区高速铁路桥梁-无砟轨道系统关键技术试验研究

Experimental research on key technology of mountainous high speed railway bridge-slab track system

以京福客专闽赣段为代表的山区铁路线路具有太阳辐射强、气候多变、地形地质条件复杂的特点,其桥隧众多。针对山区高速铁路桥梁-无砟轨道系统的环境特征和结构特点,开展箱梁-无砟轨道温度场测试、桥隧过渡段钢轨非线性温度分布测试,以及列车作用下桥梁-双块式无砟轨道动力响应测试。研究结果表明:箱梁及无砟轨道温度场呈非线性分布,可在我国铁路规范的基础上,将箱梁顶板温度梯度拟合为指数函数、将底板温度梯度拟合为线形函数;桥隧过渡段钢轨纵向存在较大温差,温差幅度可达-5~21℃;列车运行引起的结构竖向加速度从钢轨、轨道板、道床板到桥面依次降低,轨道结构耗能作用明显。

Mountainous railway lines, represented by the Fujian-Jiangxi section of Beijing-Fuzhou passengerdedicated line, have features like strong solar radiation, changeable climate and complex terrain and geologicalconditions and they normally have a large number of bridges and tunnels. In view of the environmental andstructural features of mountainous high-speed railway bridge-slab track system, the box girder-slab tracktemperature field test, rail nonlinear temperature distribution test of bridge-tunnel transition section andbridge-double block slab track dynamic response test under the action of the train were carried out. Result showsthat： considering the temperature field distribution of the box girder-slab track is nonlinear, the box girder rooftemperature gradient can be fitted to exponential function and the bottom temperature gradient to linear functionbased on China’s railway specification; there is a large temperature difference in the rail longitudinal direction ofbridge-tunnel transition section, and the temperature amplitude can be up to -5~21℃; the structural verticalacceleration caused by train operation reduces in turn from rail, track slab, track bed slab to the bridge deck, andenergy dissipation effect of track structure is obvious.