加筋边坡筋材内力的非线性弹性增量分析

Nonlinear Elastic Incremental Analysis for the Reinforcement Loads of Reinforced Slopes

针对目前工作应力状态下加筋边坡设计方法的不合理性,介绍了一种新的分析计算思路。基于潜在滑裂面处的筋土变形协调和非线性弹性邓肯-张土体本构关系,利用广义胡克定律推导得到非线性弹性增量算法。并通过3个不同倾角的边坡算例,将分析结果与有限元结果进行对比。结果表明:当坡面垂直时,增量算法与有限元解匹配度极高,表明该算法极适合于加筋边坡坡面垂直的情况;当坡面与竖直方向的夹角增大时,增量算法的偏差将逐渐变大,可通过坡面倾角折减系数予以修正。增量算法具备简洁、实用、高效的工程要求特点,具有广阔的应用空间。期望本研究成果能促进筋土相互作用机理清晰化和加筋边坡设计方法合理化。

A non-linear elastic incremental analysis method for reinforcement loads is introduced in view of the fact that most available methods are not suitable for reinforced soil slopes under working stress conditions. The method is based on the generalized Hooke＇s law in the light of the soil-reinforcement compatible deformation at the potential failure surface and the nonlinear elastic constitutive relation of soil with Duncan-Chang model. The analytical results of three slope examples with different inclination angles by incremental analysis method are compared with those by finite element method. The comparison results reveal a very high accordance between the two methods for vertical slopes,which indicates that the incremental analysis method is very suitable for reinforced vertical slopes; but when the angle between slope surface and vertical direction increases,the difference of the results increases,which could be modified by reduction factor. Incremental analysis method has a broad application range with advantages of being simple,practical and efficient. This research is expected to promote understandings of the mechanism of the interaction between soil and reinforcement,and shed some light on the design of geosynthetic-reinforced slopes.