开口薄壁杆件缀板反弯点处剪力解析解及其力学特性

Research on Analytical Method and Mechanic Property of Shear Force at Inflection Point on Batten Plates in Open Thin-walled Bar

基于Vlasov约束扭转理论,运用符号函数将开口薄壁杆件约束扭转分段函数化简,明确各约束情况下的初始状态向量元素特征,推导出偏心轴向载荷作用下缀板加强开口薄壁杆力法方程的解析式。继而针对简支梁,给出缀板反弯点处剪力解析解。与传统方法对比,表明该方法能在更短时间内获得同等求解精度。最后以两缀板加强的槽型钢架为例,分析缀板处的剪力峰值和疲劳强度随缀板间距的变化规律。结果表明:在相同外双力矩作用下,两缀板加强体系的剪力峰值小于单缀板加强体系;且制约缀板破坏的因素是静强度,并非疲劳强度。

Based on Vlasov theory, the piecewise function of open thin-walled bar in constraint torsion is simplified with the application of symbolic function, and the property of initial state vector fnr all kinds of constraints is explicated by the results of obtaining analytical expression of open thin-walled bar with batten plates under longitudinal load, and the analytical solution of shear force at inflection point on batten plates is derived aiming to the model of simply supported beam. Compared with the conventional method, the method of this paper obtains the same computational accuracy in shorter time. Finally, taking the channel section steel frame reinforced by two batten plates as an example, the peak value of shear force and fatigue strength along the distance between battens arc analyzed. Results show ： the peak value of shear force in two-batten system is much smaller than the one in single-batten system, and the restraining factor of the destruction in batten plates is static intensity, not fatigue.