基于修正气候指数的路基平衡含水率预估经验公式  

Empirical Formula for Predicting the Equilibrium Moisture Content of Subgrade Based on Modified Climate Index

作　　者：杨声[1] 谢伟[2] 章定文[2] 

机构地区：[1]宿迁市交通工程质量监督站,宿迁市223800 [2]东南大学交通学院,南京市210096

出　　处：《公路》2016年第12期28-34,共7页Highway

基　　金：中央高校基本科研业务费专项资金项目;项目编号2242014R30020;2013年宿迁市交通运输局科技课题;项目编号201310

摘　　要：公路路基土含水率受气候影响显著,季节变换将会导致路基土含水率的变化。结合文献中压实路基土含水率的实测结果,分析了压实路基土平衡含水率随气候条件变化的规律,讨论了降雨量、蒸发量等与路基平衡含水率的相关关系;为考虑季节变化修正气候指数,以月降雨量/月蒸发量为基本计算因子,建立了月降雨量/月蒸发量与路基含水率的关系,得到了基于修正气候指数的路基土平衡含水率预估经验公式,并采用文献中实测数据验证该经验公式的合理性。分析结果表明,不同土类路基压实土在相同气候条件下平衡含水率存在差异,但平衡含水率与最优含水率的差值(即路基土含水率增量)相近;路基土含水率与降雨量/蒸发量的关系曲线离散性较大,而基于修正气候指数的路基含水率预估结果与实测值较为吻合;路基土含水率随修正气候指数的增大迅速增大,当修正气候指数增大到3以后,路基含水率随修正气候指数的增大变化平缓;误差分析和文献中实测数据分析表明,文中经验公式可预测不同气候条件下路基土平衡含水率。The equilibrium moisture content of subgrade is significantly affected by climate, and seasonal changes lead to the evolution of moisture content. Based on measured results of compacted soil moisture content with different climate condition in literatures, the variation law of equilibrium moisture content of subgrade compacted soil is analyzed, and the relationship between the equilibrium moisture content and climate index factor （TMI） is explored. The climate index factor is modified and an empirical formula is also proposed to predict subgrade moisture content based on modified climate index. At last this model is verified and the error is also analyzed. The results show that the equilibrium moisture content of various subgrade compacted soils are different with the same climatic condition, but the increment of subgrade moisture content is similar. The predicting data based on the ratio of precipitation and evaporation shows large different with the measured results. However, the predicting data based on modified climate index is in accord with the measured results. Equilibrium moisture content increases rapidly with increasing of modified climate index, and it changes smoothly after modified climate index reach to 3. Error analysis and measured data in literatures validate the accuracy of the proposed empirical formula for predicting the equilibrium moisture content of the subgrade.

关 键 词：路基 平衡含水率 气候指数 降雨量/蒸发量 修正气候指数 

分 类 号：U416.1[交通运输工程—道路与铁道工程]