疏干孔负压抽水治理铁路路基冻害主要影响因素分析

Analysis of Main Factors Influencing Treatment of Freezing Injury at Railway Subgrade by Negative Pressure Pumping from Unwatering Hole

以大准铁路前石门工区某段冻害路基为依托,提出疏干孔负压抽水法治理路基冻害,考虑真空泵负压值、疏干排水孔纵向间距及仰角3个因素,用有限元法模拟了21种工况,解决疏干孔排水治理路基冻害所需时间长、路基含水量不能在较短时间内降至冻胀含水量以下的问题。结果表明:真空泵负压值应取-75 kPa;排水孔纵向间距为1.0 m;最佳仰角为5°。

Based on the freezing damaged subgrade at Qianshimen area of Datong-Zhungeer Banner Railway,negative pressure pumping from unwatering hole was proposed, and by taking negative pressure value of vacuum pump, longitudinal spacing of the holes and angle of elevation into consideration. Finite element method was used to simulate 21 kinds of working conditions, it was solved the problem which it takes long time to deal with freezing injury at subgrade by unwatering hole, so the water content thereof can not be decreased below the frostheaving water content in a short time.The result shows that, when dealing with freezing injury at subgrade along Datong-Zhungeer Banner Railway by this method, the negative pressure of vacuum pump shall be valued at-75 kPa,the longitudinal spacing of the holes at 1.0 m, and the optimal angle of elevation at 5°.