路基土湿度动态变化的测试方法

为研究路基土湿度的动态变化特征,通过设置试验路段,进行了室内模拟试验和现场测试,对路基土含水量的变化进行了研究。根据试验数据建立了重塑土体积含水量、饱和含水量与张力的关系式,预估了土的含水量,并利用建立好的土回弹模量和土含水量的模型,进而预估了土的回弹模量的动态变化特征。结果表明,土张力与含水量之间具有较好的相关性,预估值和实测值相差不到10%,具有较高的精度。因此,采用张力计测试土张力并反演路基土的含水量是可行的,若再提高张力计的测试精度,可以更准确地获得路基土湿度的动态变化特征,并对路基的设计具有重要的指导作用。

A Method for Testing Characteristics of Variation in Moisture Content of Subgrade Soil

A new method of testing for the characteristics of variation in moisture content of subgrade soil is presented.It is of great significance to test the variations in moisture contents of subgrade soils,since moisture contents of subgrade soil gradually increase after highway being built and equilibrium after period of time,and the performance of subgrade deteriorates with the increase in moisture contents of subgrade soil,which deteriorates the long-term performance of pavement.By simulation testing,the variation in moisture content of reconstituted soil are tested first,then the relationship between moisture content and suction of reconstituted soil is formulated.It is feasible to test the characteristics of variations in moisture content of subgrade soil by means of testing soil suction by in-situ tests and the testing results can meet the practice engineering needs.The precision of the soil tensiometer in this testing is still low,if the precision improves,the testing results will be more satisfying.The method has been applied in several scientific research projects in midwest and west of China recently,and the satisfying results have been achieved.