一种高墩大跨连续刚构预压技术

A High Pier and Long Span Continuous Rigid Frame Preloading Technology

高墩大跨连续刚构桥的托架预压技术,关系到成桥后的线形和施工安全。传统的施工方法通常采用托架法、堆载法对托架进行预压,消除非弹性变形、测量弹性变形量,为后续施工提供依据。堆载法预压托架的优点是模拟受力情况较为准确,但存在耗费材料多、加载时间长、加载吨位难以精确控制等问题。为了克服堆载法的缺点任湾茹河特大桥连续刚构0-1#块托架预压采用预埋牛腿托架法,通过张拉钢绞线的反作用力对托架及挂篮结构进行预压,将面荷载模拟成等效的多点集中荷载,采用此方法的优点是材料用量少、受力明确且容易控制、预压时间短、施工方便、费用节省等,同时也确保了该桥在施工过程中的安全。

The bracket preloading technology of high pier and long span continuous rigid frame bridges is related to the alignment and construction safety after completion.The traditional construction methods usually use bracket method and stacking method to preload the bracket,eliminate non elastic deformation,measure elastic deformation,and provide a basis for subsequent construction.The advantage of the preloading bracket using the stacking method is that it can accurately simulate the stress situation,but it has problems such as high material consumption,long loading time,and difficulty in accurately controlling the loading tonnage.In order to overcome the shortcomings of the stacking method,the pre compression of the 0-1#block bracket of the continuous rigid frame of the Renwan Ruhe Bridge adopts the pre buried bracket method.The bracket and hanging basket structure are pre compressed by the reaction force of the tensioned steel strand,and the surface load is simulated as an equivalent multi-point concentrated load.The advantages of using this method are low material consumption,clear and easy to control force,short pre compression time,convenient construction,and cost savings,At the same time,it also ensures the safety of the bridge during the construction process.