不同气候条件下膨胀土路堤特征参数的室内模拟实验

为了探索不同气候条件下膨胀土路基的含水量、土压力、温度、竖向胀缩变形等特征参数的基本变化规律,分别选取湖南省高速公路建设中经常遇到的弱膨胀土和中等膨胀土作为实验土样,按90%的压实度填筑,在不同排水边界条件模拟路堤在4种不同气侯条件下2组膨胀土路堤模拟实验,结果表明,膨胀土路堤中含水量、土压力、温度和胀缩变形等均受大气影响,且与路堤土的类型、密实度、排水边界条件关系密切:①埋藏较浅,含水量的变化受大气影响越大,路基中含水量越高,受气候条件影响越明显;②膨胀土路堤中的土压力变化是膨胀土路堤中含水率和气候条件综合作用的结果:③对路基温度变化影响最大的是日照,其次是降雨,阴天影响最小;④竖向胀缩变形主要发生在路堤基顶积水阶段.因此,在具体工程建设中,防渗保湿和合理设计排水系统是防治膨胀土路基遭受破坏的关键.

Indoor Simulation Test on Characteristic Parameters of Expansive Soil Embankment Under the Different Weather Conditions

In order to explore the basic laws of the characteristics parameters of expansive soil moisture,soil pressure,temperature,vertical expansion and contraction deformation in the different climatic conditions,the weak expansive soil and the medium expansive soil which frequently appears in highway construction in Hunan Province were selected as the test samples. According to 90% of the compaction degree to fill,in different drainage boundary conditions,two groups of expansive soil embank simulation experiment ...