某跨江大桥建设对堤防岸坡稳定的影响分析

Analysis on Influence of Crossing-river Bridge Construction on Stability of Embankment Slope

渗透破坏及与渗透有关的岸坡失稳是江河堤防岸坡主要的破坏形式,堤防岸坡渗流与稳定分析对于合理评价堤防岸坡的安全性、预测渗透破坏形式以及对堤防岸坡抢险加固进行科学指导等,都具有重要的理论和实践意义。当建设跨越河流的桥梁时,其基础将对堤防岸坡渗流场的分布规律产生影响。对长江某堤防工程建桥前后稳定渗流场开展对比分析,并计算堤防岸坡在建桥前后的稳定性。研究结果表明:桥梁修建前后堤防岸坡渗流场变化不大,堤身渗流溢出部位的渗透坡降变化很小,建设桥梁不会显著影响堤防的渗流稳定性;另外,根据堤防岸坡的稳定性计算成果,建桥前后安全系数变化不大,堤防岸坡能满足稳定性要求。

The seepage failure and the slope instability related with seepage are the main failure type of river embankment slopes. The analysis of embankment slope seepage and stability has the importantly theoretical and practical meanings for reasonably evaluating the security of embankment slope, forecasting the seepage failure types and scientifically guiding the rescue and reinforcement of embankment slopes. In the process of constructing the crossing-river bridge, its foundation will influence the distribution rule of seepage field of embankment slope. The article compares and analyzes the stable seepage fields before and after the construction of an embankment in Changjiang River, and calculates the stabilities of embankment slope before and after its construction. The study result shows that the seepage fields are not greatly changed before and after its construction, and the seepage gradient at the seepage overflow of embankment is changed very small. The bridge construction will not obviously affect the seepage stability of embankment. In addition, based on the stability calculation result of embankment slope, the security coefficients before and after the bridge construction are not greatly changed, and the embankment slope can satisfy the stability requirement.