直立面板式格室挡墙主动土压力计算方法探讨

Calculation method of active soil pressure on vertical panel retaining wall

基于朗肯土压力理论和格室加筋土表观黏聚力,针对直立面板式土工格室挡土墙提出一种主动土压力计算方法,将面板式挡土墙后的土工格室加固的土体和未加固的土体分别计算主动土压力并求和,将格室加固后的土压力非连续分布简化为线性分布,根据土压力合力相等的原则求得土工格室加固后的等效主动土压力系数。采用所提方法进行参数分析,揭示了由于土工格室对填料的约束效果可以减小面板后的主动土压力。算例中土工格室拉筋带高度从0 m增大到0.2 m,拉筋带间距从0.8 m减小到0.2 m,加筋土表观黏聚力从0 kPa增大到55 kPa,主动土压力系数分别减小约53.3%,33.8%,53.3%。随着墙顶面均布荷载的增加,对主动土压力减小有贡献的格室加筋土表观黏聚力范围也逐渐增大。

This paper proposes an active earth pressure calculation method for the vertical panel geocell retaining wall based on Rankine earth pressure theory and apparent cohesion of lattice reinforced soil. The geocell reinforced soil body and the unreinforced soil body are calculated separately, and then the total active soil pressure is obtained. The noncontinuous distribution of soil pressure behind geocell reinforcement is simplified to linear distribution. The equivalent earth pressure coefficient is presented based on the principle of equal soil pressure force. Parametric analysis using the proposed method yields the following conclusions. With the constraint effect of geocell on packing, the active soil pressure behind the panel is reduced. Based on the calculated examples in this paper, the geocell height increases from 0 m to 0.2 m, the geocell spacing decreases from 0.8 m to 0.2 m, the apparent cohesion force increases from 0 kPa to 55 kPa, and the equivalent earth pressure coefficient declines approximately 53.3%, 33.8%, and 53.3%. As the top load of the wall increases, the range of geocell reinforced soil apparent cohesion force gradually increases.