植入锚杆的桥梁扩大基础受力变形分析  

Stress and Deformation Analysis of Bridge Enlarged Foundations with Implanted Anchors

作　　者：冉敬爱 杨正祥 刘克蛟 RAN Jingai;YANG Zhengxiang;LIU Kejiao(Gansu Provincial Transportation Planning,Survey&Design Institute Co.,Ltd.,Lanzhou 730000,China)

机构地区：[1]甘肃省交通规划勘察设计院股份有限公司,兰州730000

出　　处：《交通科技》2024年第6期76-81,共6页Transportation Science & Technology

摘　　要：针对岩石地基因基岩分化、裂隙发育等导致桥梁扩大基础在地震工况下不满足稳定性要求,以及岩石地基采用嵌岩桩施工难的问题,提出在岩石扩大基础中植入锚杆(索)的新型桥梁扩大基础。依托实际桥梁采用数值模拟方法,对比分析不同地震工况下该扩大基础及其受力变形特征。结果表明,在地震动峰值加速度0.20g以上,新型扩大基础墩台抗倾覆、抗滑移稳定性均满足要求;在最不利荷载组合工况下,新型扩大基础沉降量比嵌岩桩小15%~23%,有效减小了基础沉降。最后按“逆向设计”思路,梳理了新型桥梁扩大基础在不同地震荷载工况下锚索用量的计算流程,为后续同类工程项目提供参考与借鉴。A new type of bridge expansion foundation was proposed in order to solve the problems that the stability of bridge expansion foundation cannot meet the requirements under seismic conditions due to the differentiation of rock and fissure development and the difficulty of using rock-socked piles for rock foundation construction.Based on the numerical simulation method of the actual bridge,the stress and deformation characteristics of the new expanded foundation and the expanded foundation under different seismic conditions were compared and analyzed.The results show that the anti-overturning and ant-sliding stability of the new expanded foundation can meet the requirements when the peak acceleration of ground motion is above 0.20 g.Under the most unfavorable load combination conditions,the settlement of the new expanded foundation is about 15%~23%smaller than that of the rock-socketed pile,effectively reducing the foundation settlement.Finally,according to the idea of“reverse design”,the calculation flow of the anchor cable dosage of the new bridge expansion foundation under different seismic load conditions is sorted out,providing reference for the subsequent similar projects.

关 键 词：桥梁工程 岩石锚杆 新型桥梁扩大基础 数值模拟 逆向设计 

分 类 号：U443.11[建筑科学—桥梁与隧道工程]