基于极限状态筋材内力分布的加筋土挡墙稳定性分析与设计优化

Stability Analysis and Design Optimization of GRS Walls Based on Distribution of Reinforcement Load in Limit State

土工合成材料加筋土挡墙由于其诸多优势被广泛应用于实际工程中。现有规范中设计方法多采用传统的主动土压力理论,经大量实测分析发现这种设计方法过于保守地估计筋材内力。文中基于库仑直线破坏模式开展加筋土挡墙稳定性极限平衡分析,逐层计算获得极限状态下筋材内力分布与墙面水平位移量。运用该方法对某电厂扩建项目的加筋土挡墙设计方案进行稳定性分析,基于筋材内力分布进行设计优化,在保证内部和外部稳定性前提下实现了筋材长度减少10%,同时使得墙面侧向变形也减小约5%。基于极限状态筋材内力分布的加筋土挡墙稳定性设计方法还可以推广应用于其他复杂情况,指导安全设计与控制。

Geosynthetic-reinforced soil(GRS)wall is widely used in engineering because of its many advantages.The traditional active earth pressure theory is often used in the existing code design method.Through a large number of actual measurements and analysis,it is found that this design method is too conservative to estimate the internal force of reinforcement.The limit equilibrium analysis of the stability of the GRS wall is carried out based on the plane failure mode,and the load distributions for each reinforcement and the horizontal displacement of the GRS wall in the limit state are calculated layer by layer.Stability analysis of a GRS wall design scheme for a power plant expansion project is made through the method mentioned above.Based on the load distributions for reinforcement,the design is optimized.Under the premise of ensuring the internal and external stability,the length of the reinforcement is reduced by 10%,and the lateral displacement of the wall is reduced by 5%.The stability design method of the GRS wall based on the load distributions for reinforcement in the limit state can also be applied to other complex situations to guide the safety design and control.