一种新型剁式悬臂挡土墙特征分析

Characteristic Analysis of a New Structure of Counterfort Cantilever Retaining Wall

针对传统垛式挡土墙中上墙与下墙之间缺乏有效连接的局限性,提出一种新型剁式挡土墙:在下墙顶部的填土侧设置一个支墩,但上墙的墙趾板沿竖向压在下墙的支墩上。上、下级挡土墙之间本质上是相互分离的,上墙承担的部分竖向荷载可通过支墩直接传递给下墙。基于有限元方法,对所提新型挡土墙进行对比分析,计算结果表明:下墙顶部设置支墩后,下墙原本较大的侧向土压力值逐渐变小,上墙原本较小的侧向土压力值有所变大,下墙与上墙的侧向土压力得到了合理的转移与重分配;下墙底板上部的竖向土压力降低,下墙底板底部墙趾板附近的最大竖向应力进一步增大;上墙有绕支墩向填土侧旋转滑裂破坏的趋势。

In view of the lack of effective connection between the upper and lower walls of the traditional counterfort retaining wall,a new structure of counterfort retaining wall is proposed:a buttress is set on the top of the lower wall,and the toe plate of the upper wall is vertically pressed on the buttress of the lower wall.The upper and lower retaining walls are essentially separated from each other.Partial vertical loads borne by the upper wall can be transmitted directly to the lower wall through the buttress.Based on the finite element method,the characteristics of the new structure retaining wall are analyzed.The results show that when a buttress set on the top of the lower wall,the lateral earth pressure of the lower wall decrease,and the lateral earth pressure on the upper wall becomes larger,the lateral earth pressure of the lower wall and the upper wall has been reasonably transferred and redistributed.The vertical earth pressure on the upside of heel plate of the lower wall is reduced,and the maximum vertical stress near the bottom of the heel plate of the lower wall is further increased.The upper wall has the tendency of rotating and sliding failure around the buttress at sliding failure.