港珠澳大桥沉管隧道基槽试挖槽及航道疏浚影响分析  

Analysis of the impact of trial excavation and channel dredging on the foundation trench of the immersed tube tunnel of the Hongkong-Zhuhai-Macao Bridge

作　　者：姬海 张志刚[1] JI Hai;ZHANG Zhi-gang(CCCC Highway Consultants Co.,Ltd.,Beijing 100010,China)

机构地区：[1]中交公路规划设计院有限公司,北京100010

出　　处：《中国港湾建设》2024年第9期19-24,共6页China Harbour Engineering

摘　　要：外海沉管隧道基槽边坡坡率取值对工程经济性和施工风险有较大的影响,基槽附近的航道疏浚可能导致基槽回淤异常,影响基槽边坡稳定性从而影响施工进展。通过开展隧址区原位试挖槽试验和临近航道疏浚数值模拟分析基槽边坡稳定和回淤情况,为港珠澳大桥沉管隧道基槽方案设计与施工提供技术支持,研究结果表明:1)经历汛期影响周期的观测显示,1∶5、1∶6、1∶8、1∶10坡比的基槽边坡均未出现结构性的变化,整体稳定。2)试挖槽槽底区域呈持续回淤状态,边坡外区域呈现出回淤与冲刷交替出现的现象,但整体变化幅度不大。3)航道疏浚距离基槽位置越近对基槽回淤影响越大,基槽淤厚最大的位置出现在基槽与航道交汇处。The value of the slope ratio of the foundation trench for offshore immersed tube tunnels has a significant impact on the engineering economy and construction risks.Dredging of waterways near the foundation trench may lead to abnormal siltation of the foundation trench,affecting the stability of the foundation trench slope and thus affecting construction progress.By conducting in-situ trial excavation tests in the tunnel site area and numerical simulation analysis of adjacent waterway dredging,the stability and siltation of the foundation trench slope were analyzed.This provides technical support for the design and construction of the foundation trench scheme for the Hongkong-Zhuhai-Macao Bridge immersed tube tunnel.The research results show that:1)Observations of the flood season impact cycle shows that the foundation trench slopes with slope ratios of 1颐5,1颐6,1颐8,and 1颐10 have no structural changes,and are overall stable.2)The bottom area of the trial excavation trench shows a continuous siltation state,while the outer area of the slope shows an alternating phenomenon of siltation and erosion,but the overall change amplitude is not significant.3)The closer the waterway dredging is to the position of the foundation trench,the greater the impact on the siltation of the foundation trench.The location where the foundation trench siltation is thickest appears at the intersection of the foundation trench and the waterway.

关 键 词：沉管隧道 试挖槽 边坡稳定性 回淤 航道疏浚 

分 类 号：U616[交通运输工程—船舶及航道工程] U459.5[交通运输工程—船舶与海洋工程]