大气降雨对土坝非饱和区含水率影响分析

Analysis About Rainfall Influence on Volumetric Moisture Content of Unsaturated Zone

运用非饱和渗流理论分析了不同降雨强度和降雨持续时间对土坝非饱和区含水率变化规律.结果显示,降雨强度越大、降雨持续时间越长,非饱和区土体含水率变化也大,坝坡表层土体较容易达到饱和,并且降雨影响深度也大,对坝坡表面湿化裂隙的产生及坝坡稳定性影响大.不管降雨强度如何,坝顶和坝坡中上部比坡体的中下部更容易受降雨浸湿.

Laws about volumetric moisture content changes and wetting deformation in unsaturated zone are analysed according to different rainfall intensities and duration by saturated-unsaturated seepage theory in this text. The result shows soil masses in surface layer reach saturation more easily under great rainfall intensity and long-lasting rainfall, at the same time, there are big infiltration depth and influence of wetting deformation. Top soil masses of dam slope soak and produce wetting more easily than low soil of slope in spite of rainfall intensity.