摘要
除土体对桩的水平作用外,将土体对桩的摩擦作用模拟为作用在桩节点上的竖向弹簧及扭转弹簧,推导竖向和扭转弹簧系数的计算公式。指出利用m法计算桩侧弹簧系数时m值选取不精确的不足,提出以桥墩实测振型和自振频率为输入,利用优化算法对土体弹簧参数进行识别的原理和步骤,分析竖向弹簧和扭转弹簧对桥墩动力特性的影响,在此基础上提出一种考虑土体摩擦效应的桥墩动力特性分析方法。105国道子牙新河桥双柱式桥墩的分析实例证明了所提方法的有效性。结果表明,土体摩擦引起的竖向和扭转弹簧对桥墩的自振频率和振型影响较大,在进行动力特性分析时不可忽略。
Apart from the lateral action of soil on the pile, by simulating soil friction with vertical and rotational springs at pile element nodes, the computational formula of vertical and rotational springs are deduced. When calculating the distributing spring constants along the pile, the possible inaccuracy in choosing the m value in the m-method is pointed out. The theory and procedure using optimization algorithm to identify the soil spring constants with measured modes and nature frequencies of piers as input are proposed. The influences of vertical and rotational springs on dynamic characteristics of piers are studied, and then an analysis method of pier dynamic characteristics considering soil friction effects is proposed. The effectiveness of the proposed method was validated by testing and analyzing the two-column piers of the Ziya Bridge on 105 National Highway. The analyzing results indicate that the vertical and rotational springs induced by the soil friction effects have great influences on the modal frequencies and mode shapes of piers, so they cannot be ignored in the dynamic characteristic analysis.
出处
《土木工程学报》
EI
CSCD
北大核心
2013年第12期74-80,共7页
China Civil Engineering Journal
基金
国家自然科学基金(51208028)
国家重点基础研究发展973计划项目(2013CB036203)
中央高校基本科研业务费专项资金(2013JBM011)
关键词
公路桥梁
桥墩
土体摩擦效应
动力特性
参数识别
roadway bridge
pier
soil friction effect
dynamic characteristics
parameter identification
