重载作用下索-桁架加固结构体系试验研究

发布时间：2018-05-24 22:11

本文选题：重载 + 桥梁加固　；参考：《土木工程学报》2017年04期

【摘要】：溪洛渡±800千伏特高压直流输电工程建设过程中,需要通过公路运输大件设备,这些设备的重量已超过途经桥梁的极限承载力,需要进行临时加固。基于此,介绍了一种重载作用下的桥梁加固技术——索-桁架加固结构体系,该体系主要由预应力钢绞线和桁架组成,通过张拉钢绞线使桁架产生顶升力以抵消桥梁板自重,达到加固桥梁的目的。为了验证该体系的合理性以及加固效果,进行了足尺试验研究,模拟了重型车辆通过一跨桥梁的整个过程,考察了桥梁板加固前后结构响应的变化,研究了钢绞线穿过多个滑轮组后的预应力损失。试验结果表明,采用索-桁架加固结构体系可以部分抵消桥梁板自重,改善桥梁板内力分布,有效提升结构承载力和刚度,桥梁板在加固后以及加载时上下表面均未发生开裂;滑轮组作为转向装置可以有效传递钢绞线内力,穿过多个滑轮组后钢绞线内力损失不大。
[Abstract]:In the construction of Xiluodu 卤800 kV UHVDC transmission project, it is necessary to transport large equipment by road. The weight of these equipment has exceeded the ultimate bearing capacity of the bridge, and it needs to be temporarily strengthened. Based on this, this paper introduces a bridge strengthening technology under heavy load, cable-truss strengthening structure system, which is mainly composed of prestressed steel strand and truss, which can make the truss produce uplift force to offset the dead weight of bridge slab by tensioning steel strand. The purpose of strengthening the bridge is achieved. In order to verify the rationality of the system and the reinforcement effect, a full-scale experimental study was carried out to simulate the whole process of heavy vehicle passing through the one-span bridge, and the structural responses before and after the reinforcement of the bridge slab were investigated. The prestressing loss of steel strands passing through multiple pulleys is studied. The test results show that the cable-truss strengthened structure system can partially offset the dead weight of the bridge slab, improve the internal force distribution of the bridge plate, effectively enhance the bearing capacity and stiffness of the structure, and the upper and lower surfaces of the bridge slab do not crack after strengthening and loading. As a steering device, pulley group can effectively transfer the internal force of steel strand, but the loss of internal force of steel strand after passing through multiple pulleys is small.
【作者单位】：浙江大学;浙江省电力设计院有限公司;
【基金】：国家自然科学基金(51578494) 国家重点研发计划课题(2016YFC0800206)
【分类号】：U445.72

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