用于网架结构加固的索撑、套管集成加固法及工程应用

Cable brace and outer sleeve integrated reinforcement method for grid structure and its engineering application

某游泳馆设计于1993年,竣工于1996年,屋盖为正放四角锥螺栓球平板网架。在改建过程中,因有使用功能升级及设备改造,对其进行检测、鉴定及加固,鉴定结果表明,屋盖网架结构不能满足安全性及耐久性要求。针对节点及杆件的不同受力特征,采用了不同的加固方法:采用增设加劲肋解决平板支座承载力不足问题,采用新型预应力高钒索、钢支撑及套管集成加固法解决杆件、节点承载力不足及杆件稳定性不足的问题。预应力高钒索、支撑及套管集成加固方法形成了网架结构加固的成套技术体系,避免了网架结构加固中的焊接作业,消除了焊接应力的影响以及焊接过程中钢管高温软化可能导致的非预期破坏,大大缩短了施工作业时间,取得了良好的社会与经济效益,为以后类似改造工程提供了借鉴。

A theater designed in 1993,completed in 1996,the roof is orthogonal square pyramid grid structure with bolted-ball joint.In the process of renovation,due to the use function upgrades and equipment transformation,the original grid structure can’t meet the safety and durability requirements,the detection,identification and reinforcement is needed. According to the reinforcement principle of the structure,a new reinforcement method is adopted for the different force characteristics of the joints and the bars. For the boltedball joint,the additional flat steel gussets are used to reinforce the anchorage ribs,the prestressed cable and brace reinforcement method is used to strengthen the bar which bearing capacity does not meet the requirements,the outer sleeve reinforcement is used to strengthen the bar which the pressure stability does not meet the requirements. The bearing capacity of the joint,the problem of the safety of the bar and the welding work in the reinforcement of the truss structure are reduced,the influence of the welding stress and the possible unexpected damage from high temperature softening of the steel pipe during the welding process is effectively eliminated,the construction time is greatly shorted,and good social and economic benefits are achieved. It also provides a reference for similar projects.