基于主成分-逐步回归的大跨弯连续刚构桥冲击系数计算  

Calculation of Impact Coefficient of Long-span Curved Continuous Rigid Frame Bridge Based on Principal Component-stepwise Regression

作　　者：韩智强 左新黛[2] 周勇军[3] 刘世忠 晋民杰 HAN Zhi-qiang;ZUO Xin-dai;ZHOU Yong-jun;LIU Shi-zhong;JIN Min-jie(School of Traffic and Logistics,Taiyuan University of Science and Technology,Taiyuan Shanxi 030024,China;Research Institute of Highway,Ministry of Transport,Beijing 100088,China;Engineering Research Center for Large Highway Structure Safety of Ministry of Education,Chang'an University,Xi'an Shaanxi 710064,China)

机构地区：[1]太原科技大学交通与物流学院,山西太原030024 [2]交通运输部公路科学研究院,北京100088 [3]长安大学公路大型结构安全教育部工程研究中心,陕西西安710064

出　　处：《公路交通科技》2022年第1期72-80,共9页Journal of Highway and Transportation Research and Development

基　　金：国家自然科学基金项目(5198063);公路院科技创新专项资金项目(2019-I113);山西省科技攻关项目(201803D31076)。

摘　　要：为确定大跨弯连续刚构桥冲击系数的计算公式,基于结构动力学和车桥耦合相关机理,组建了车辆与桥梁的振动方程。通过轮桥位移协调关系,确定车桥相互作用,采用MATLAB软件编译大跨弯连续刚构桥车桥耦合分析模块。通过采用主成分分析法,对多指标参数进行降维处理。综合考虑特征值大于1和方差累计贡献率大于90%的目标参数,确定了桥面不平整度、曲率半径和墩高为主要敏感参数,通过逐步回归法拟合回归桥梁挠度、弯矩和扭矩冲击系数计算公式。结果表明:桥梁挠度冲击系数受桥面不平整度、墩高的影响性较为显著,而曲率半径对其影响相对较小;桥梁弯矩冲击系数受桥面不平整度的影响较为显著,墩高和曲率半径对其影响相对较小;桥梁扭矩冲击系数受桥面不平整度和曲率半径的影响较大,而墩高影响较小。拟合回归的桥梁冲击系数计算公式相关系数均大于0.94,相关性较好,且所有冲击系数计算公式中桥面不平整度的标准化相关系数均在0.9以上,表明该因素对大跨弯连续刚构桥冲击系数的整体影响很大,建议后续规范修订中考虑该因素的影响。In order to determine the calculation formula of impact coefficient of long-span curved continuous rigid frame bridge,based on the mechanism of structural dynamics and vehicle-bridge coupling,the vibration equation of vehicles and bridges is established.The vehicle bridge interaction is determined through the wheel-bridge displacement coordination relationship,and the vehicle-bridge coupling analysis module of the long-span curved continuous rigid frame bridge is compiled by using MATLAB software.The dimensionality of multiple parameters is reduced by using the principal component analysis method.Comprehensively considering the target parameters with eigenvalue greater than 1 and cumulative contribution rate of variance greater than 90%,the bridge deck roughness,radius of curvature and pier height are determined as the main sensitive parameters.The calculation formulas of bridge deflection,bending moment and torque impact coefficient are fitted and regressed by stepwise regression method.The result shows that(1)the impact coefficient of bridge deflection is significantly affected by the bridge deck roughness and pier height,while the curvature radius has little influence on it;(2)the impact coefficient of bridge bending moment is significantly affected by the bridge deck roughness,while the pier height and curvature radius have little influence on it;(3)the bridge torque impact coefficient is greatly affected by the bridge deck roughness and curvature radius,while the pier height has little influence on it.The correlation coefficients of the bridge impact coefficient calculation formula fitted by regression are greater than 0.94,the correlation is good,and the standardized correlation coefficients of bridge deck roughness in all impact coefficient calculation formulas are more than 0.9,indicating that this factor has a great influence on the impact coefficient of the long-span curved continuous rigid frame bridge.It is suggested to consider this factor in subsequent specification revisions.

关 键 词：桥梁工程 冲击系数 主成分-逐步回归 大跨弯连续刚构桥 桥面不平整度 

分 类 号：U441.2[建筑科学—桥梁与隧道工程]