浸水条件下重载铁路风积沙路基变形特性研究

Research on Deformation Characteristics of Aeolian Sand Subgrade of Heavy Haul Railway Under Water Immersion Condition

季节性浸水风积沙路基极易遭受不良地质与水力的双重影响,是沙漠地区特殊工程问题。依托某新建煤运专线重载铁路工程,采用理论分析、数值模拟等方法,构建重载铁路风积沙路基仿真模型,计算浸水因素对重荷条件下风积沙路基变形特性的影响。研究表明:降雨期间,坡脚含水量骤然增长以及地势低洼引起的排水困难等问题,会导致风积沙路基积水形成浸水路基;单侧浸水状态下风积沙路基渗流场呈现“左高右低”分布趋势;在一侧水位固定、另一侧水位逐渐抬高工况下,右侧路基边坡薄弱点分别出现在左侧浸水高度4 m、右侧浸水高度2 m两种情况。

The seasonal water-soaked wind-cum-sand roadbed is highly susceptible to both adverse geological and hydraulic effects, and is a special engineering problem in desert areas. Relying on a new coal transportation line heavy-duty railroad project, theoretical analysis and numerical simulation are used to construct a simulation model of wind-accumulated sand roadbed for heavy-duty railroad and calculate the influence of soaking water factors on the deformation characteristics of wind-accumulated-sand roadbed under heavy load conditions. The conclusion of the study shows that: during the rainfall, the sudden increase of water content at the foot of the slope and the difficulty of drainage caused by the low terrain will lead to the accumulation of water in the wind-cum-sand roadbed to form a submerged roadbed;the seepage field of the wind-cum-sand roadbed under the one-sided submerged condition shows the distribution trend of “high left and low right”;under the condition that the water level on one side is fixed and the water level on the other side is gradually raised, the weak points on the right side of the roadbed appear in the two cases where the left side and the right side are immersed with water height of 4 m and 2 m respectively.