富水卵石层重力式锚碇选型及稳定性分析  

Type Selection and Stability Analysis of Gravity Anchor Foundation in Water-rich Pebble Layer

作　　者：张洪翠 殷源 尚宏艳 程树范 ZHANG Hongcui;YIN Yuan;SHANG Hongyan;CHENG Shufan(Hubei Province Road and Bridge Co.,Ltd.,Wuhan 430056,China)

机构地区：[1]湖北省路桥集团有限公司,武汉430056

出　　处：《交通科技》2024年第4期68-73,共6页Transportation Science & Technology

基　　金：国家自然科学基金项目(42107175)资助。

摘　　要：富水卵石地层中由高承压水头导致的悬索桥重力式锚碇稳定性不足问题突出。文中依托宜都长江大桥南岸锚碇工程,采用简化理论计算和三维数值模拟相结合的方法,重点研究承压水头变化对其稳定性和沉降变形的影响,并结合实际工况提出基础形式优化方案。结果表明,枯水期浅埋扩大基础锚碇造价低,易于施工,具有可推广性。然而,扩大基础底面积大,承压水头增高时,基底压力减小、摩擦减弱会显著降低其抗滑安全系数。通过基底齿坎或阶梯构造夹持卵石的方法,可以有效增强锚碇的整体稳定性。针对文中案例,保持基底面积不变,增加10 m×10 m的齿坎后,高水头条件下其抗滑稳定性系数由1.99增大为2.21,安全性显著增加。The problem of insufficient stability of the gravity anchor of the suspension bridge caused by high pressure waterhead in the rich water pebble layer is outstanding.Taking south anchor of Yidu Yangzhi River Bridge as example,the impact of changes in pressure waterhead on its stability and settlement deformation was studied based on simplified theoritical method and numerical method,and an optimization plan for the foundation form based on working conditions was provided.The results indicate that the cost of shallow buried and expanded foundation anchoring during dry season is low,easy to construct,and has generalizability.However,the decrease in pressure and friction between foundation and rock will significantly reduce the anti-skid safety factor due to large spread foundation area and increased pressure waterhead.In this situation,the overall stability of the anchorage body can be effectively enhanced based on the foundation toothed ridges structure or the clamping pebbles layer.For the case in the paper,keeping the base area unchanged and adding a toothed ridge with length of 10 m and width of 10 m,the anti-skid stability coefficient under high waterhead conditions can be increased from 1.99 to 2.21,with an significantly increasing in safety.

关 键 词：锚碇基础 承压水头 深厚卵石地层 齿坎构造 稳定性计算 

分 类 号：U443.24[建筑科学—桥梁与隧道工程]