大规格角钢螺栓连接节点准距研究

Study on directrix of bolted joint of large size angle steel

我国现有规范给出的大规格角钢准距是基于常规角钢的研究结果得来的,不能充分发挥大角钢的力学优势。对节点螺栓布置的约束条件进行分析,并研究了大角钢节点的破坏截面及减孔数计算方法。在此基础上,以∠250×26为例进行了57组准距方案的有限元计算,对比分析了节点的极限承载力、变形及破坏形态等力学特征,进而得到大角钢的理想准距。结果表明:大角钢的理想准距与螺栓规格有关,现有规范不区分螺栓规格的做法不合理。提出了适用于∠250系列角钢的理想准距方案,可为工程实践提供借鉴。

Large size rolled angle directrix of current design codes were given on the foundation of research for conventional angle steel, which cannot make full use of mechanical advantage of large size rolled angles.Constraint conditions of joint bolts arrangement were firstly studied, and the failure sections and hole-reduction number calculation methods were analyzed afterwards. On this basis, finite element analysis work of different directrix values of 57 sets of alignment schemes was carried out by taking ∠250×26 as an example, and the ideal directrix values of large size angle steel were obtained through comparative analysis of the mechanical characteristics such as the joint’s ultimate bearing capacity, deformation and failure mode. The results show that the ideal directrix of large size angle steel is associated with the bolt’s specification, and it is unreasonable not to distinguish bolt specification in the current codes. Finally, scheme of optimal rolled angle directrix for∠250 series was put forward, which can provide references for practices.