长期放置的预应力箱梁在设计荷载作用下的结构性能试验  

Structural Performance Test of Long-placed Prestressed Box Girder under Design Load

作　　者：刘斌 LIU Bin(Xinjiang Highway and Bridge Test Center Co.,Ltd.,Urumqi,Xinjiang 830000,China)

机构地区：[1]新疆公路桥梁试验检测中心有限责任公司,新疆乌鲁木齐830000

出　　处：《黑龙江交通科技》2024年第6期96-99,共4页Communications Science and Technology Heilongjiang

摘　　要：为探究长期放置的预应力箱梁在设计荷载作用下的结构性能,以一批存放时长超过两年,存放环境多为昼夜温差超过30℃的极端天气条件下的预应力混凝土箱梁为研究对象,采用抽样检测的方式,对箱梁进行外观检查和工作性能强度检测,测定预应力混凝土箱梁在设计荷载作用下控制截面的应力(应变)、挠度,研究结果表明:箱梁腹板在沿预应力钢束波纹管位置处出现长度不等的纵向裂缝,其强度匀质系数Kbt在1.04~1.12之间,平均强度匀质系数Kbm>1;变校验系数范围为0.6~0.9之间,相对残余应变在2%~17%之间,整体抽查结果混凝土强度状况良好,试验控制荷载作用下,工作性能正常,承载能力满足设计要求。In order to explore the structural performance of long-placed prestressed concrete box beams under the action of design loads,a batch of prestressed concrete box beams stored for more than two years in extreme weather conditions where the temperature difference between day and night exceeds 30℃were mostly used as research objects,and the appearance inspection and working performance strength inspection of the box beams were carried out in the way of sampling detection.The stress(strain)and deflection of the control section of the prestressed concrete box girder under the design load are measured.The results show that the longitudinal cracks of different lengths appear in the web of the box girder along the position of the prestressed steel bellows.The strength uniformity coefficient K bt is between 1.04 and 1.12,and the average strength uniformity coefficient K bm i s greater than 1.The variable calibration coefficient ranges from 0.6 to 0.9,and the relative residual strain ranges from 2%to 17%.The overall sampling results show that the strength of concrete is in good condition.Under the test control load,the working performance is normal,and the bearing capacity meets the design requirements.

关 键 词：预应力箱梁 结构性能 抽样检测 

分 类 号：U442[建筑科学—桥梁与隧道工程]