用于岛状冻土地区路基换填的新型材料及其性能

New Subgrade Replacement Materials for Segregated Frozen Ground Area and Their Properties

针对现有岛状冻土地区冻胀路基的维护技术存在的突出问题,为最大限度地降低利用传统换填材料处治对道路通行能力的影响,研究提出了两种具备良好隔温性能,且能够快速硬化、施工便捷的新型填料。基于可控性低强度材料(CLSM)的高流动性、自填充、自密实特性,对其掺入泡沫颗粒,并通过对两种配合比进行无侧限抗压强度试验、导热系数试验和抗冻融循环试验,确定换填材料的泡沫颗粒的最佳体积比为1%。从技术经济角度出发,提出治理方案为:对沉陷面积不大的区域,采用全厚度换填修复;对沉陷面积较大的区域,采用XPS板+CLSM换填修复。最后通过现场试验段的实施,分析结果表明,本文提出专用于现有岛状冻土地区路基换填的新型材料,能够达到实际的工程应用要求。

Aiming at the existing problems in the maintenance technology of the frost heaving subgrade in segregated frozen ground area,in order to minimize the effect on traffic by using the traditional replacement materials,we presented 2 kinds of new packing material which have the performance of good insulating,hardening rapidly and constructing conveniently. Based on the property of high mobility,self-filling and selfcompacting of CLSM,we mixed it with foam particles. The optimum volume ratio of the foam particles in filling material is determined as 1% through unconfined compressive strength test,coefficient of thermal conductivity test and freezing-thawing resisting cycling test based on 2 proportions. From the perspective of technology and economy,we put forward the following treatment scheme： adopting the full thickness of replacement in small subsidence and XPS board ＋ CLSM replacement repair in large subsidence region.Finally,through the implementation of test section,the result shows that the new materials dedicating to the subgrade replacement in the existing segregated frozen ground area can achieve the requirement of engineering application.