考虑侧向渗流边界条件的结构基底扬压力计算方法

Calculation Method for Uplift Pressure of Structural Foundation Considering Lateral Seepage Boundary Conditions

扬压力是结构稳定设计中的重要荷载,但结构基底扬压力计算的常用方法——图形法仅能考虑上、下游水头边界条件而无法考虑结构基底侧向渗流边界条件的影响。因此,以某水电站工程为例,通过建立溢洪道基底岩体的二维平面渗流分析模型,研究基底水流向下游及两侧边渗流时扬压力的分布规律。结果表明,在考虑侧向渗流边界条件的影响下,所建模型计算的基底扬压力值相比于图形法更小,扬压力的分布结果更符合实际工程渗流规律。

Uplift pressure is an important load in structural stability design,and the graphical method is a commonly used method for calculating the uplift pressure of structural foundations.But its limitation is that it can only consider the upstream and downstream water head boundary conditions and cannot consider the impact of the lateral seepage boundary conditions of the structural foundation.Taking a certain hydropower station project as an example,this article establishes a two-dimensional plane seepage analysis model of the spillway foundation rock mass to study the distribution law of uplift pressure when the foundation water flows downstream and on both sides.The results indicate that considering the influence of lateral seepage boundary conditions,the base uplift pressure value is smaller compared to the graphical method,and the distribution of uplift pressure is more in line with the actual engineering seepage law.