HEC-RAS模型在密江特大桥防洪评价中的应用

介绍了HEC-RAS模型计算桥梁壅水的基本原理和主要步骤,并以吉林市至珲春市高速铁路客运专线密江特大桥的壅水计算为实例,采用HEC-RAS模型,模拟了300年一遇、100年一遇、50年一遇、20年一遇以及10年一遇设计洪水频率下建桥前后的河道水面线,进而求得桥梁阻水壅高值和壅水长度。计算结果表明,HEC-RAS模型在分析计算桥梁对河道的阻水壅高影响时方便实用,工程适用性较好,可供防洪工程决策制定的参考。

Application of HEC-RAS Model for Evaluation of Flood Control of Mijiang Super-long Bridge

This paper introduces the basic principles and main procedures of the HEC-RAS model in calculating the bridge backwater.The HEC-RAS model is then used in the calculation of the Mijiang super-long bridge backwater at the Jilin-Hunchun high-speed railway for passenger traffic.Different scenarios of the frequency of flood events are simulated,including once in 300 years,once in 100 years,once in 50 years,once in 20 years,and once in 10 years.The river water surface lines before and after the bridge construction are simulated under the different scenarios of flood events,and thus the block water height and backwater height of the Mijiang bridge are obtained.The results show that the HEC-RAS model is convenient and practical in analyzing and calculating the effects of the bridge backwater height,and it has engineering applicability and can provide reliable references for decision-making in flood control projects.