黄河万家寨水利枢纽工程人行索桥主索锚碇系统加固技术

黄河万家寨水利枢纽工程人行索桥原为一临时建筑物,经过十多年的应用,现欲使之成为永久结构,需要对主桥上部结构按照永久结构体系进行加固。索桥主索锚碇系统是整个索桥的生命线,它的耐久性和可靠性是整个索桥可持续使用的关键。由于索桥主缆采用50年代进口钢丝绳系统,而且是施工周转材料,同时索桥原锚固系统采用契紧加绳夹的结构形式,为保证新的加固体系与原体系共同起作用,对新的锚固系统提出了非常大的难题。经过不同试验研究,最终采用“三片式夹持,环氧砂浆握裹,支承箱传力”的组合锚固新系统。该系统采用特殊的张拉工艺和顶压工艺,能够使用新夹持系统与原系统共同受力。而且具有良好的握裹和防护的作用,在同类型结构体系中具有很好的借鉴和参考作用。

Reinforcement Technology of Main Cable Anchorage System of Pedestrian Cable Bridge of Wanjiazhai Dam on the Yellow River

The pedestrian cable bridge of Wanjiazhai Dam on the Yellow River was originally a temporary structure. After more than ten years of application, it is now required to strengthen the superstructure of the main bridge according to the permanent structure system in order to make it a permanent structure. The main cable anchorage system of a cable bridge is the lifeline of the entire cable bridge, and its durability and reliability are key to the sustainable use of the entire cable bridge. Due to the use of imported steel wire rope systems from the 1950s as the main cable of the cable bridge, which is a construction turnover material, and the fact that the original anchorage system of the cable bridge used a structure of tight fitting and rope clamps, it posed significant challenges to ensure that the new reinforcement system worked together with the original system. After different experimental studies, a new combined anchoring system of "three piece clamping, epoxy mortar wrapping, and support box force transmission" was ultimately adopted. This system adopts special tensioning and top pressing processes, which can use the new clamping system to bear the force together with the original system, and has good gripping and protective effects. It has a good reference and reference value in the same type of structural system