地震作用下钢筋混凝土圆形空心墩有效刚度研究  

Study on effective stiffness of circular hollow reinforced concrete piers under seismic load

作　　者：侯泽群 李贵乾 吴章旭 孔凯歌 HOU Zequn;LI Guiqian;WU Zhangxu;KONG Kaige(Guangxi Communications Design Group Co.,Ltd,Nanning 530029,China;Guangxi Vocational and Technical College of Communications,Nanning 530216,China)

机构地区：[1]广西交通设计集团有限公司,广西南宁530029 [2]广西交通职业技术学院,广西南宁530216

出　　处：《世界地震工程》2024年第2期174-185,共12页World Earthquake Engineering

基　　金：广西高校中青年教师科研基础能力提升项目(2023KY1161)。

摘　　要：基于52个圆形空心墩拟静力试验数据及等效屈服位移三分量模型,分析了既有有效刚度公式对圆形空心墩的适用性;讨论了圆形空心墩有效刚度的主要影响因素,以轴压比、纵筋率、剪跨比及空心率为控制因素,标定了圆形空心墩有效刚度计算公式;并通过实尺寸及缩尺寸桥墩滞回曲线的模拟验证了建议公式的有效性。研究表明:绝大多数有效刚度既有公式在平均意义上严重高估了圆形空心墩的有效刚度,且变异系数较大;圆形空心墩有效刚度随轴压比、纵筋率和剪跨比的增大而增大,随空心率的增大而减小,剪跨比与空心率的耦合效应可通过等效剪跨比考虑,且有效刚度随等效剪跨比的增大而增大;建议公式给出的有效刚度计算值与试验值之比的均值及变异系数分别为1.04和0.21,与既有有效刚度公式相比,均值更合理而且离散性更小,提高了圆形空心墩有效刚度的预测精度;建议公式计算的有效刚度能较准确地模拟实尺寸及缩尺寸圆形空心墩拟静力滞回曲线,及相应的首次屈服刚度、加卸载刚度。Based on the quasi-static test data of 52 circular hollow piers and the three-component yield displacement model,the applicability of existing effective stiffness formulas for circular hollow piers was analyzed,the main influencing factors of the effective stiffness of circular hollow piers were discussed.The effective stiffness calculation formula for circular hollow piers was calibrated by using axial compression ratio,longitudinal reinforcement ratio,shear span ratio,and hollow ratio as the control factors,and the validity of proposed formula was verified by simulating the hysteresis curves of full-scale and scale circular hollow piers.The results show that most existing effective stiffness formulas significantly overestimate the average of effective stiffness of circular hollow piers,with large coefficient of variation.The effective stiffness of circular hollow pier increases with the increase of axial compression ratio,longitudinal reinforcement ratio and aspect ratio,and decreases with the increase of hollow ratio.The coupling effect of aspect ratio and hollow ratio can be considered by the equivalent aspect ratio,and the effective stiffness increases with the equivalent aspect ratio.The mean value and coefficient of variation for the ratio of the calculated effective stiffness value given by the proposed formula to the test value are 1.04 and 0.21,respectively.Compared with existing effective stiffness formulas,the supposed formula provides higher accuracy and greatly reduces the degree and possibility of possible overestimation.The effective stiffness calculated by the suggested formula can accurately simulate the hysteretic curve,the yield stiffness,and the loading and unloading stiffness of circular hollow piers.

关 键 词：钢筋混凝土 圆形空心墩 有效刚度 空心率 回归分析 

分 类 号：P315.9[天文地球—地震学] U442.55[天文地球—固体地球物理学]