降雨蒸发作用下膨胀土湿热和裂隙特性室内模拟试验

发布时间：2018-05-11 22:35

  本文选题：膨胀土 + 裂隙　； 参考：《岩土力学》2014年09期

【摘要】：以广西白色强膨胀土为研究对象,对有、无植被覆盖的膨胀土样进行蒸发、降雨再蒸发试验,研究降雨、蒸发过程对膨胀土湿热和裂隙拓展特性的影响。结果表明,植被覆盖土样表面的反射量比无植被覆盖土样小100W/m2左右,土样表面温差小5~6℃。无植被覆盖土样经历降雨过程后,在相同蒸发条件下,土样表面裂隙率由1.28%增加到3.82%,表层土体累计脱湿量由3.42%增加到11.17%,脱湿速率由0.59%/d增加到1.44%/d,表层土体温度变化平均值由13.1℃增加到14.9℃。可见,降雨、蒸发过程使得土体水量变化加大,水分迁移速率增加,温度变化加剧,土体趋于破碎。植被覆盖土样经历降雨过程后,在相同蒸发条件下,土样表面并未出现明显裂隙,表层土体累计脱湿量由3.16%变为2.36%,脱湿速率由0.58%/d变为0.37%/d,表层土体温度变化平均值由0.58℃变为0.37℃。可见,短期降雨、蒸发过程对植被覆盖下膨胀土的持水能力影响不大。
[Abstract]:Taking the white strong expansive soil in Guangxi as the research object, the experiments of evaporation and re-evaporation of expansive soil samples without vegetation cover were carried out to study the effect of rainfall and evaporation process on the hygrothermal and fracture expansion characteristics of expansive soil. The results show that the surface reflectance of vegetation covered soil sample is smaller than that of non-vegetation covered soil sample, and the temperature difference of soil sample surface is 5 ~ 6 鈩，

本文编号：1875932