钢框架结构基于变形可靠度的全概率抗震设计

FULL PROBABILITY ASEISMIC DESIGN OF STEEL FRAME STRUCTURES BASED ON DEFORMATION RELIABILITY

我国抗震设计规范的抗震设计方法并不是真正意义上的概率极限状态设计,结构可靠度的应用也没有体现出结构的体系可靠度设计水平,因此该文提出了基于变形可靠度验算的二阶段抗震设计方法。该方法采用结构可靠度的数值模拟方法,通过验算小震作用下结构构件承载能力极限状态下的抗震可靠度,验算结构小震作用下正常使用极限状态下和大震作用下侧向倒塌极限状态下的整体变形抗震可靠度,实现结构构件和结构体系两个层次上的全概率设计。该文给出了该方法的设计步骤,并结合钢框架结构设计实例验证了该方法的可行性。基于可靠度理论的全概率抗震设计方法是抗震设计发展的必然趋势,该文提出的方法将为结构的全概率抗震设计提供一定的借鉴。

The aseismic design method in Chinese code is not a real probability limit state design;the structural reliability is not applied in a structural system reliability level.A two-stage,full probability aseismic design method is put forward,which is based on a direct failure probability checking format.In this method,the failure probability is calculated by a numerical simulation method.During the first design stage,the strength reliability index of the member-level ultimate limit state under a minor earthquake is checked against the target reliability index,and meanwhile,the global elastic deformation reliability of a serviceability limit state under a minor earthquake and the global elastic-plastic deformation reliability of a lateral collapse limit state under a major earthquake are also checked.The two-level full probability aseismic design of a component and a structure are both accomplished.The design procedures of the full probability design method are brought forward,which are checked with a steel frame structure design example.The full probability aseismic design method based on reliability theory is an advanced method,which will be a developing trend of aseismic design.