粘贴钢板法加固轴心受压柱的可靠度分析

根据现行的加固设计规范提出了确定轴心受压柱可靠度指标β的方法,并且分析了由于功能改变而进行粘钢加固的构件可靠度指标的影响因素。运用静态随机过程模拟,建立了实用的轴心受压构件荷载模型和抗力模型。按照现行规范编制了计算机程序求解极限状态方程,得出粘钢加固柱的可靠度指标。并且进一步分析了可靠度指标的影响因素,按照重要性,它们依次是混凝土强度变异系数、荷载提高程度和施工荷载与设计荷载的比值。因此,加固设计的首要任务是进行既有结构的性能评价,如确定混凝土强度的变异系数等;此外,控制荷载的增加可以使结构具有足够的可靠度;最后,卸载施工也是确保结构可靠度指标满足要求的有效措施。

Reliability Analysis of Axially Compressed Columns Reinforced by Bonding Steel Plate

The purpose of this paper is to determine the reliability index β of axially compressed columns according to the current reinforcement design specification and to analyze the factors influencing β of bonding steel reinforced members due to function alteration.Stationary binomial process is applied to establish practical load model and resistance model for axial compressed member.And a computer program is developed as per the current specifications to obtain the reliability index of steeled columns through resolving the limit state equation.Furthermore,influence factors of reliability index βare studied and they are concrete strength variation coefficient,the load increase factor as well as the ratio of construction load to design load by the order of importance.Therefore,performance assessment of existing structure,especially determining concrete strength variation coefficient is the first important task for reinforcement design,and secondly,load increase control is effective to ensure sufficient reliability.Lastly,applying load-off construction could help make reliability index acceptable.