关键词: 装配式挡土墙, 现场试验, 绕墙底转动(RB)模式, 非极限主动土压力, 水平层分析法

Abstract:

The distribution and magnitude of earth pressure behind wall is the key basis for the design of assembled retaining wall. We investigated the displacement patterns and soil pressure distribution of retaining walls under loading conditions via designing and conducting field tests of a new type of assembled concrete retaining wall. Based on the field tests, we established the theoretical computational model of retaining wall with sloping and rough wall backs yet with no cohesive fill. In consideration of factors such as displacement pattern and magnitude, soil arching effect, and interlayer shear stress, we adopted the horizontal layer analysis method to derive an earth pressure formula for retaining wall rotating around the base (RB), defined as an RB displacement mode.Results indicate a sound overall performance of the retaining wall, rigidly rotating around the base. Under the RB mode, soils at the top of the wall reach the active limit state first, progressively followed by lower depths. Limit state will be reached when soil displacement S_c reaches 7 mm at any depth, corresponding to S_c=0.16%H(H is the wall height). The theoretical value closely matches test value, demonstrating the applicability of our derived formula in predicting the distribution and magnitude of earth pressure during the retaining wall’s rotation around the base. Furthermore, as the rotation intensifies, the concavity of the earth pressure distribution curve becomes more pronounced, and the height of the resultant soil pressure force point initially decreases and then recovers. A rotation angle η=0.007 rad is identified as the critical threshold for the retaining wall to reach its active limit state.

Key words: assembled retaining wall, field test, displacement mode of rotating around the base (RB), non-limit active earth pressure, horizontal layer analysis method