关键词: 岩土工程, 剪胀角, 边坡体系, 抗滑桩, 安全系数, 有限元强度折减法

Abstract: Based on numerical calculation examples the influence of soil expansion on earth side slope and the stability of side slope system was studied and two different views regarding dilatancy impact on slope stability were compared and these two different methods of finite element strength reduction and gravity loading method were tested and verified. The test results show that the finite element strength reduction method has its limit in stability analysis of side slope of non-associated platic earth nature and was only effective when statisfying the dilation angle less than internal friction angle in course of redcution. In addition, study was carried out regarding the view which stated that it is a safe method to take approximate dilation angle 0°. After study made on the side slope strengthened with anti-slide pile it was found that the less is the dilation angle, the less is the deflection of anti-slide pile and the maximum earth pressure acting on the pile shaft, which presented the characteristics that earth flow through pile body more easily. Hence considering from the respect of side slope safety factor, the minimum safety factor can be obtained by taking dilation angle approximately 0° , which is a safe practice. But considering from aspect of design of anti-slide pile this method is not safe. It is hence suggested that the value setting of dilation angle shall be reasonably considered by specific issue analysis according to specific conditions of slope.

Key words: geotechnical engineering, angle of dilation, slope system, anti-slide pile, factor of safety, strength reduction finite element method