下穿隧道开挖土钉墙支护设计的理论计算与数值模拟对比分析

Comparison between Theory Calculation and Numerical Simulation on Support Design of Soil Nailing Wall in Excavation of Under-passing Tunnel

以某实际工程下穿隧道开挖区域边坡防护为背景,根据现场地质勘察资料,结合土钉墙理论计算公式,在符合其构造要求前提下,对开挖区域进行了土钉支护设计。基于土钉墙的理论计算结果,运用有限元软件建立土钉墙支护模型,在满足设计要求的坡顶竖向沉降及水平位移的同时,将数值模拟的土钉长度与理论计算的土钉长度进行了对比分析。结果表明:两种方法计算的土钉长度基本吻合,说明数值模拟结果存在一定的可靠性与合理性。

Taking the slope protection within excavation area of under-passing tunnel in an project as the background, the soil nailing support therein was designed on the premise of conformance to the structural requirement, which depended on the field geological investigation and the theoretical formula of soil nailing wall. Based on the result of the theoretical calculation thereof, the supporting model of the soil nailing wall was established with finite element software so that, when meeting both the vertical settlement and the horizontal displacement of the slope top required by the design, the values of soil nail＇s length obtained from the numerical simulation and the theoretical calculation were compared. The result shows that the two values from the two methods agree substantially, demonstrating the result of numerical simulation has reliability and rationality to certain degree.