钢筋混凝土结构疲劳时变可靠性分析

Time-variant reliability assessment of reinforced concrete structures under fatigue loadings

钢筋混凝土结构在疲劳荷载作用下材料要发生劣化,从而结构抗力降低,可靠度发生改变.笔者应用非线性有限元理论计算出结构"危险部位"钢筋和混凝土材料的疲劳应力,通过材料疲劳过程中强度和刚度的损伤劣化模型计算出结构的剩余抗力,并对其进行时变可靠性评估和剩余疲劳寿命预测.其研究方法适用于复杂结构形式和任意边界条件的钢筋混凝土结构疲劳验算和可靠性评估.

Materials of reinforced concrete structures under fatigue loadings deteriorate,resulting in structure resist reducing and reliability changing.Firstly material fatigue stresses in most dangerous positions of reinforced structures have been calculated by means of non-linear FEM.Then the residual resist of structure has been calculated by way of material strength and stiffness evolution model.Thus the time-variant reliability assessment and residual fatigue life of structures can be obtained.The research is applicable to fatigue checking computations or reliability assessment of reinforced concrete structures with complicated structure style and boundary conditions.