沙坡头黄河特大桥深水围堰方案设计与仿真分析

The Design and Simulation Analysis of the Deep Water Cofferdam for the Yellow River Mega Bridge at Shapotou

沙坡头黄河特大桥桥址处所处地质条件为卵石层,由于工期和起吊条件的限制,主墩的深水承台施工设计了单壁钢套箱的围堰方案。为了降低围堰的入土深度,箱底封底混凝土采用分隔仓水下浇筑,以保证封底混凝土的厚度和质量。此外,针对围堰结构特点,建立了围堰的整体有限元模型,针对施工最不利工况进行计算的结果表明围堰的受力、位移均满足要求,且与施工过程的实测变形测量结果吻合。单壁钢套箱的设计方案取得了良好的经济效益,且保证了工期。

As the Yellow River Mega Bridge at Shapotou is located in a pebble stratum,and its construction duration and lifting conditions are limited,a cofferdam scheme of the single-walled steel box is designed for the construction of the deep-water platform of the main pier.In order to reduce the depth of the cofferdam going into the ground,the sealing concrete for the bottom of the box is poured underwater with the help of the separating compartment to ensure the depth and quality of the sealing concrete.Besides,upon the basis of considering the structural characteristics of the cofferdam,a finite element model is also established for it.The calculated results in the stress and deformation of the cofferdam from the most unfavorable construction conditions are found to be able to meet the needs of the design and to be in agreement with the site-measured results in deformation in the course of construction.The design scheme of the single-walled steel box obtains good economic benefits and ensures the construction duration requirement.