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结合国家自然科学基金重点项目《受施工扰动影响的土体环境稳定理论与控制方法》，以基坑工程作为研究的工程背景，系统地研究了开挖扰动和降雨入渗对非饱和土工程性质和工程稳定性影响。主要研究结论是： （１）开挖扰动对土体的强度参数有明显的影响，但对内磨擦角φ值的影响更为明显。 （２）电镜观察结论表明：①原状土一般为架空结构或骨架结构，结构疏松，颗粒之间呈点接触或者接触程度较差，粘土矿物胶结，整个界面比较平稳，无明显折断或错动痕迹；②开挖扰动后土体的原始结构受到损伤，颗粒之间的胶结物（粘土矿物）发生不同程度的破裂、断开或错动，局部胶结差的地方，原来胶结在一起的颗粒被撕裂断开：③微观结构的损伤是导致土体强度降低的内因，造成这种损伤的关键因素就是基坑开挖后边坡土体内应力场的变化，电镜照片有助于从微观角度揭示受开挖扰动影响的土体强度降低的本质。 （３）针对具体工程的计算结果表明；开挖扰动对边坡稳定性的影响幅度大约在１０％左右。当边坡安全储备比较大时，开挖扰动的影响尚不至于造成边坡失稳，但是在边坡安全储备不大且在降雨等其他不利因素的共同作用下，开挖扰动的影响就不能忽略。 依据非饱和土的强度理论和常规的边坡稳定性分析方法，建立了分析?
Combined with the key project of National Natural Science Foundation of China, “Soil Stability Theory and Control Method of Soil Affected by Construction Disturbances”, taking the foundation pit engineering as the research background, the dissertation systematically studied the influence of excavation disturbance and rainfall infiltration on the engineering properties of unsaturated soils And the stability of the project. The main conclusions are as follows: (1) Excavation disturbance has a significant effect on soil strength parameters, but the effect on internal friction angle φ is more obvious. (2) Electron microscopy observations show that: ① undisturbed soil is generally overhead structure or skeleton structure, the structure is loose, there is a point of contact between the particles or the degree of contact is poor, the clay mineral cementing, the entire interface is relatively stable, no obvious fracture or misplaced traces ; ② After excavation disturbed the original structure of the soil was damaged, the cement between the particles (clay minerals) occurred in varying degrees of rupture, disconnection or dislocation, local cementing poor place, the original cement particles together were torn Cracked open: ③ microstructure damage is the internal cause of the strength of the soil to reduce, the key factor causing this damage is the change of stress field in slope soil after foundation pit excavation, electron microscopy photographs help to reveal from the microscopic point The nature of soil strength reduction affected by digging disturbances. (3) According to the calculation results of concrete engineering, the influence of excavation disturbance on slope stability is about 10%. When the slope safety reserve is relatively large, the influence of excavation disturbance will not cause the slope instability. However, if the safety reserve of the slope is not large and the adverse factors such as rainfall and other adverse factors are combined, the impact of excavation disturbance can not be ignore. Based on the strength theory of unsaturated soils and the conventional slope stability analysis method, an analysis is established.