富水含砂软土地层施工对临近桥梁影响分析

针对深厚软土地层、高承压水等不利条件下的基坑开挖及顶管施工对临近桥梁结构影响问题，以临近武汉常青路高架桥梁某电力通道工程施工为背景，构建了三维数值分析模型，系统分析了基坑开挖及顶管施工对高架桥梁结构位移及受力的影响。研究表明：基坑开挖及顶管施工引起的桥梁结构最大水平向、竖向位移分别为1.31mm、1.13mm，桥梁结构最大轴力、桥桩弯矩分别为6694.4 kN、263.3kN·m，施工前后轴力累计变化率为-1.79%，弯矩累计变化率为1.35%，桥梁结构受力变化较小，均在规范限值以内，表明本工程设计方案是可行的、合理的。设计方案和研究成果可为临近桥梁结构安全施工提供支撑。

Analysis of the Impact of Construction on Adjacent Bridges in Soft Soil Areas with Water-rich Sand Stratum

Aiming at the problem of foundation pit excavation and pipe jacking construction on adjacent bridge structures under unfavorable conditions, such as deep soft soil stratum and high confined water etc., a 3-D numerical analysis model was constructed based on the construction of an electric power passage near the elevated bridge of Changqing Road in Wuhan. Then, the influence of foundation pit excavation and pipe jacking construction on the displacement and stress of the elevated bridge structure was systematically analyzed. The results show that the maximum horizontal and vertical displacement of the bridge structure caused by excavation of foundation pits and pipe jacking construction are 1.31mm and 1.13mm, respectively. Also, the maximum axial force and bending moment of the bridge structure are 6694.4kN and 263.3kN m. The accumulative change rate of axial force and bending moment before and after construction are -1.79% and 1.35% respectively. The stress variation of the bridge structure is relatively small, both within the specification limits, indicating that the design scheme of this project is feasible and reasonable. The design scheme and research results can provide support for the safe construction of adjacent bridge structures.