高温冻土区高速公路特殊结构路基地温分布特征及降温效果分析

发布时间：2018-08-27 19:39

【摘要】：根据青海省共(和)玉(树)高速公路特殊结构路基的地温监测资料,对3种路基(XPS保温板路基,碎石路基和通风管路基)填土与地基土的地温变化情况及冻土人为上限变化与天然上限附近热流密度状况以及路基温度场的非对称性进行对比分析,研究3种路基的地温分布特征及降温效果。测试结果表明:(1)3种路基在左、右路肩的不同深度处均呈现出明显的升温趋势,观测期内,XPS板路基升温幅度最大;碎石路基次之,通风管路基最小;(2)路基修筑完成初期,3种路基的多年冻土人为上限均存在不同程度抬升;到第3年,3种路基下多年冻土人为上限均下降;(3)3种路基的冻土上限附近热量收支均呈吸热状态,吸热量大小顺序为XPS板路基碎石路基通风管路基;(4)3种路基内部温度均呈左高右低的不对称分布。综上研究结果,建议在今后高温冻土区的高速公路建设中优先采用通风管路基。同时,为减小地温不均匀分布造成的路基纵向裂缝等病害,路基的横断面应采取差异化设计的原则。
[Abstract]:Based on the ground temperature monitoring data of the special structure Subgrade of Gonghe Yushu Expressway in Qinghai Province, the ground temperature changes of three kinds of subgrade (XPS heat preservation plate subgrade, gravel subgrade and ventilation pipe subgrade) and the artificial upper limit of frozen soil, the state of heat flux near the natural upper limit and the asymmetry of Subgrade Temperature Field were studied. The test results show that: (1) the three kinds of roadbed in different depths of the left and right shoulders show obvious warming trend, XPS plate roadbed warming range is the largest during the observation period; gravel roadbed is the second, ventilation pipe roadbed is the smallest; (2) at the beginning of the construction of the roadbed, three roadbed permafrost. In the third year, the artificial upper limit of permafrost under the three kinds of roadbed decreased; (3) The heat budget near the upper limit of permafrost of the three kinds of roadbed was endothermic, and the order of heat absorption was XPS plate gravel subgrade ventilation pipe subgrade; (4) The temperature inside the three kinds of roadbed was asymmetrical distribution of left high and right low. The research results suggest that ventilation pipe subgrade should be preferred in highway construction in high temperature permafrost area in the future. In order to reduce the longitudinal cracks and other diseases caused by uneven ground temperature distribution, the principle of differential design should be adopted in the cross section of subgrade.
【作者单位】：北京交通大学土木建筑工程学院;青海省交通科学研究院;
【基金】：国家自然基金资助项目(41271072) 青海省科技项目(2013 J 770) 神朔科技项目(2015 10)~~
【分类号】：U416.1

【相似文献】