膨胀土填方边坡裂隙发育规律试验

Experiment of expansive soil fissure traits in fill slope

为了解决膨胀土填方边坡的稳定性问题,查明膨胀土易产生浅层破坏的原因,研究膨胀土中裂隙发育的规律,在明确填方边坡的裂隙类型为风化裂隙的基础上,利用矢量图技术定量化描述了裂隙的演化规律,获取了裂隙的几何形态及裂隙度等一系列参数;进而分别探讨了干湿循环、含水量及大气温度等因素对膨胀土填方边坡裂隙发育的影响。研究结果表明:监测期内裂隙分布不具备定向规律,且系统格局非常混乱,基本不存在相互平行的裂隙;裂隙在降雨时闭合,在蒸发过程中再次开裂,并互相连通逐渐发育成网状,但到一定程度后基本稳定;随着循环次数的增加,土体逐步走向完全破碎。

In order to solve the problem of slope stability of expansive soil,this paper found out the reasons why expansive soil prone to shallow damage,and studied the regulation of development of fissure in expansive soil.Type of the fill slope fissures was defined to be weathering fissures based on analysis and discussion of fissure classification and causes.This paper photographed the development process of fissures,and then used vector technique to quantitatively describe the evolution rules of fissures and obtained parameters of geometry and fissures degrees,it also explored the influence of precipitation-evaporation,water content and atmospheric temperature.The results show that fissure distribution is irregular during the monitoring period,and the system pattern is very chaotic.Basically,there exist no parallel cracks.Fissures close under rainfall and crack during evaporation,gradually develop into a mesh after interconnection,and to a certain level it basically become stable.With the increase of cycle times,soil is gradually completely broken.