关键词: 桁架, 腹杆, 计算长度, 半刚性, 稳定性

Abstract:

According to the classical elastic stability theory of framework and the related research results, the stability equations of member bar group and the equations to calculate the effective length coefficient of compressive brace are deduced by considering the joint rigidity and the adjacent brace rigidity. Then, the tables for the calculation of effective length of compressive brace in truss are provided for engineering application. As compared with the existing calculation methods, the proposed equations are more general. Calculated and analytical results show that, by considering the rigidity restraint of the adjacent braces at the calculating joint, the calculated effective length of compressive brace in truss slightly decreases, and that, within most range of the rigidity ratio, the calculated effective length coefficients are smaller than those provided by current criteria.

Key words: truss, brace, effective length, semi-rigidity, stability