基于响应面法的履带起重机桁架臂压弯构件稳定性的可靠性分析

摘要

考虑履带起重机桁架臂构件几何尺寸、材料性能和作用载荷的随机性,基于响应面法建立了以臂架中压弯杆件稳定性为失效模式的可靠性分析模型,该模型用响应面函数代替真实的隐式功能函数,结合一次二阶矩法计算可靠度。利用该模型对现有某型号履带起重机桁架臂压弯杆件稳定性可靠性进行分析,计算结果表明,压弯杆件稳定性可靠度与载荷呈现非线性变化趋势,反映了可靠度随载荷变化的规律。%Considering the randomness of geometrical dimensions,material properties and applied loads of crawler crane′s boom system,the reliability analysis model of compressive-bending member′s stability was established based on Response Surface Method(RSM),which involves response surface functions replacing performance functions and first order second moment(FOSM) method.The model was used to calculate the reliability of compressive-bending members of a certain existing crawler crane′s boom.The results indicate that the relationship between the reliability of compressive-bending member′s buckling and applied loads takes on nonlinear tendency,reflecting the law of reliability varying with loads.