高速铁路高架线路列车运营对既有线路基的影响研究

Research on effect of train running on elevated line of high-speed railway on existing railway subgrade

为分析高速铁路高架线列车运行对既有线路基影响,建立桥墩-大地-既有线路基有限元模型,结合测试验证模型可靠性,分析不同行车条件对既有线路基应力状态的影响关系,讨论高速铁路轨道平顺性恶化和土体模量降低对既有线路基的影响,预测既有线路基表层累计变形。研究得到,既有线自身列车运行对路基应力状态的影响占主要地位,高速铁路运营对既有线路基应力状态的贡献度很小,不会对既有线路基使用寿命造成明显影响,高速铁路桥墩与既有线距离按限界控制即可满足要求;在轨道平顺性恶化和土体模量降低条件下,高速列车运营引起的既有线路基应力增加不超过0.5 kPa。

The effect of train running on elevated bridge of high-seed railway on existing railway subgrade is analysis by means of the establishment of a pier-soil-subgrade model which is proved to be reliable by comparison with in-field test results. First, the stress state of the existing railway at different traffic conditions is simulated while the influence of rail irregularities and soil modulus is discussed; then, the cumulative settlement deformation under traffic loads of trains is predicted. The research results show that running trains on elevated high-speed railway bridge have little effect on the stress state and accumulated deformation of existing railway subgrade. As a result, the distance between piers and the line spacing in existing railway just need to adjust by the clearance diagram requirements. In case of bad rail irregularities and soil modulus decline, the stress increase induced by high-speed trains won’t exceed 0.5 kPa.