桩基础刚度对混凝土曲线梁桥冲击系数的影响  

The effect of multi-pile foundation stiffness on impact factor of a highway concrete curved bridge

作　　者：邢世玲[1] 朱利明[1] 姜长宇[2] 

机构地区：[1]南京工业大学交通运输工程学院,江苏南京210009 [2]东南大学建筑设计研究院有限公司,江苏南京210096

出　　处：《南京工业大学学报（自然科学版）》2017年第4期111-117,共7页Journal of Nanjing Tech University(Natural Science Edition)

基　　金：国家重点基础研究发展计划(973计划)(2013CB036203)

摘　　要：以墩-梁固结类型的混凝土曲线梁桥为对象,通过算例分析固结墩的桩基础刚度变化对自振特性和桥跨结构内力和位移冲击系数的影响。基桩用梁单元模拟,土对桩的横向水平力用一系列水平弹簧来模拟,桩底支承反力和桩周摩阻力用一系列竖向弹簧来模拟。结果表明:固结墩桩基础刚度对桥跨结构低阶竖弯频率和低阶扭转频率的影响均很小;车辆行驶速度对桥跨结构冲击系数的影响比固结墩桩基础刚度的影响大,但总体而言桩基础刚度对汽车冲击系数的影响较小;汽车横向作用位置对弯矩和位移冲击系数影响很小,但对扭矩冲击系数影响显著,且偏心行驶作用下的扭矩冲击系数小于中心行驶作用下的冲击系数值。For the concrete curved bridge with the intermediate piers as the single column and consolidated beam,the effect of multi-pile foundation stiffness under consolidated pier on structural dynamic characteristics and impact factor were analyzed. Piles were taken as beams and boundary constraints were simulated by a series of horizontal springs and vertical springs.Results indicated that the influences of foundation stiffness under consolidated pier on vertical bending frequency values of low order mode and torsional frequency values of low order mode were both very small; the effect of vehicle speed on impact factor was larger than the multi-pile foundation stiffness,and overall the multi-pile foundation stiffness had less effect on the impact factor values of the span structure; the lateral position of the vehicle on the bridge deck had almost no influence on the dynamic magnification factors of moment and displacement,but the impact on the dynamic magnification factors of torque was obvious,and the impact factor of torque under partial loads was less than the impact of the factor values under center loads.

关 键 词：冲击系数 混凝土曲线梁桥 桩基础刚度 

分 类 号：U441.3[建筑科学—桥梁与隧道工程]