摘要
对桥梁进行现场荷载试验,主要包括不同静力荷载工况下的挠度与应变测试,跑车、跳车与地脉动等动力试验工况下的自振频率与动力增大系数等参数测试。研究结果表明:试验桥跨的实测挠度与应变均小于理论值,结构的刚度与强度满足设计与使用要求,且有一定的安全储备;试验桥跨的实测挠度随荷载的增加呈线性变化,结构处于弹性工作范围;试验桥跨的实测应变沿梁高呈线性变化,控制截面实测数据拟和的中性轴至梁底的距离与其理论计算基本一致,结构实际受力状况良好,与设计理论吻合很好,达到设计目的;不同测试方法获得的实测自振频率较为接近,且均大于理论计算频率,试验桥跨的实际刚度大于理论刚度,结构整体刚度良好;实测动力增大系数总体较小,行车舒适性较好;桥梁结构的整体静动力性能良好,各项指标满足规范要求,承载能力满足设计要求。
Field load tests were carried out,mainly including deflection and strain tests under different static load conditions,natural vibration frequency and dynamic increase factor tests under dynamic tests such as traffic running test,jumping test and earth pulsation test.The results show that the measured deflection and strain were both less than the theoretical value,the stiffness and strength of structure met design and use requirements with certain safety reserve;the deflection of tested span varied linearly with load increase and the structure was in elastic working range;the measured strain of tested span varied linearly along the height of main beam,the distance from the simulated neutral axis of measured value to the bottom of the beam was basically consistent with the theoretical value.The actual mechanical property of bridge was in good condition,which was highly consistent with the design theoretical,and achieved the design goal.The measured natural frequencies obtained by different test methods were close to each other and bigger than the theoretical,the actual stiffness of tested span was greater than the theoretical stiffness,and the overall stiffness of the bridge was good,the dynamic increase factor was small in general,and the driving comfort of the bridge was good.The static and dynamic performances of the whole structure were good,the indexes met the code requirements and the bearing capacity met the design requirements.
作者
王浩
孙强
WANG Hao;SUN Qiang(China Northeast Municipal Engineering Design驭Research Institute Co.,Ltd.,Changchun,Jilin 130021,China)
出处
《中国港湾建设》
2020年第3期33-38,共6页
China Harbour Engineering
基金
国家重点研发计划(2016YFC0802403)。
关键词
连续梁桥
现场试验
静力性能
动力性能
挠度
应变
频率
动力增大系数
continuous beam bridge
field test
static performance
dynamic performance
deflection
strain
frequency
dynamic increase factor
