阜新-朝阳高速公路段湿陷性黄土路基处理方法及效果

Subgrade Treatment Effects for Collapsibe Loess Subgrade of Fuxin-Chaoyang Freeway in West of Liaoning Province

对辽西黄土进行强夯法、灰土挤密桩法和冲击碾压法加固路基的试验研究，旨在确定辽西湿陷性黄土路基处理的技术方案和技术参数。以现场测试和室内试验相结合的方法，对试验路段的不同处理方法处理前后的黄土物理力学性质进行了对比。结果表明：（1）夯击能为800～1600kN·m、夯击数不小于8击，对处理深度4～6m的黄土较为有效；（2）灰土挤密桩法可以消除桩深范围内及桩端下一定范围内的黄土湿陷性，较适合于深厚湿陷性黄土的处理；（3）冲击碾压法适合处理黄土厚度较小和表层黄土的处理，碾压遍数以40遍为最佳，其处理深度在1m左右。这些成果为该地区湿陷性路基处理提供了参考。

In order to determine the technical program and technical parameters for stabilizing collapsible loess of subgrade treatment in west of Liaoning, some experimental research of stabilizing subgrade, such as, dynamic compaction, impact-rolling and lime soil pile, has been carried out. Combining in-situ test with laboratory experiment, the physical and mechanical properties in experimental areas are compared before and after treatment, and some conclusions are drawn out such as： （1） It is effective to treat 4 m to 6 m in depth under 800 kN·m to 1 600 kN·m in compaction energy without with not less than 8 tamper times; （2） Lime soil pile is suitable to improve subgrade with thick loess, which can dispel the loess collapisibility either in the range of pile length or in a certain extent from pile end; （3） The method of impact-rolling is useful to treat loess with the less thickness of the layer and topsoil with about lm in depth, and impact rolling is optimal in 40 times. The result mentioned above provided a technical references for collapsible loess sudgrade treatment in this area.