南京小龙湾自锚式悬索桥荷载试验  

Load tests of Nanjing Xiaolongwan self-anchored suspension bridge

作　　者：端茂军[1] 李国芬[1] 李建慧[1] 索小灿 

机构地区：[1]南京林业大学土木工程学院,南京210037

出　　处：《林业工程学报》2016年第6期137-141,共5页Journal of Forestry Engineering

基　　金：教育部高等学校博士学科点专项科研基金项目(20133204120015);江苏省高校自然科学研究项目(12KJB560003);江苏高校优势学科建设工程资助项目(PAPD);江苏高校品牌专业建设工程项目(PPZY2015A063)

摘　　要：为判断南京小龙湾自锚式悬索桥的实际承载力,评价桥梁使用阶段受力性能,保证桥梁正常使用,开展现场静荷载试验,测试静载试验下主缆的竖向变形及内力增量、加劲梁的竖向变形、吊杆索力增量、加劲梁各截面应力及桥塔塔底应力增量、桥塔塔顶纵向偏位等静力参数;测试动载试验下桥梁的动力特性及动力响应。静载试验结果表明,理论计算值与静载试验结果基本一致,理论分析模型很好地反映了实际桥梁的受力特性,静载试验后结构残余变形较小,在设计可变作用下结构处于弹性受力状态,说明南京小龙湾自锚式悬索桥实际受力状况较好,主体结构具备足够的强度和刚度;动载试验结果表明桥梁动力特性良好,桥面平整度对车辆冲击效应影响较大,桥梁运营阶段应加强养护工作,保证桥面平顺,减少车辆冲击效应。There are great differences in mechanic properties between self-anchored and earth-anchored suspension bridge. The stress condition of self-anchored suspension bridge is more complex, however, the mechanism of which is still unclear at present. The load test is the most direct and effective way to evaluate the performance and operation status of the bridge. However, the load test of self-anchored suspension bridge is less studied. Nanjing Xiaolongwan bridge is a self-anchored concrete suspension bridge with two-tower, two-main cable plane. The span layout of bridge is （44＋96＋ 44） m, and there are 33 couples of vertical hangers, including 19 ones on the main span and 7 ones on each side span. To ensure the normal use of Nanjing Xiaolongwan self-anchored suspension bridge, a load test was conducted for evalua- ting actual carrying capacity and mechanical behavior in serviceable state. Deformation of stiffening girder, longitudinal displacement of bridge tower top, force increment of hanger and main cable, section stress of stiffening girder and bridge tower were tested under static load conditions while dynamic characteristic and its response were tested under live load ones. Results of static load test indicated that the theoretical values generally matched with the values of static load test. Testing coefficients were lower than 1. O, which was between 0. 80 and 1.00. The mechanical characteristics of actual bridge can be reflected well by the theoretical analysis model, and the small residual deformation after load static test and the elastic stress state under the live load indicated the Nanjing Xiaolongwan self-anchored suspension bridge had e- nough stiffness and strength to conform to the requirements of design loading grade. The results of live load test indicated that Nanjing Xiaolongwan self-anchored suspension bridge had good dynamic characteristics. The impact factors were small and not more than 0.03 while the vehicles were normal driving. However, the impact factors were increased sharply to 0

关 键 词：自锚式悬索桥 静载试验 动载试验 承载能力 

分 类 号：U448.25[建筑科学—桥梁与隧道工程]