基于可靠度的FRP筋材料分项系数的确定  

RELIABILITY-BASED CALIBRATION OF MATERIAL PARTIAL FACTOR OF FIBER REINFORCED POLYMER (FRP) ROD

作　　者：何政[1] 李光[2] 

机构地区：[1]东北大学资源与土木工程学院,沈阳110004 [2]哈尔滨工业大学土木工程学院,哈尔滨150090

出　　处：《工程力学》2008年第9期214-223,共10页Engineering Mechanics

基　　金：国家自然科学基金项目(50208007);教育部留学回国人员科研启动基金项目

摘　　要：基于中国混凝土结构设计资料以及构件几何尺寸与材料力学性能的概率统计参数,建立了FRP筋混凝土梁受弯正截面承载力的计算公式,并采用验算点法计算了在六种荷载效应比情况下的受弯承载力可靠指标平均值,最后在考察FRP筋材料分项系数对可靠指标平均值影响的基础上,建议GFRP筋和CFRP筋的材料分项系数统一取为1.25。可靠度分析表明:过于保守的FRP筋材料分项系数只能使得截面发生混凝土破坏模式的概率增大,而这种破坏模式对应的可靠度水平基本与FRP筋材料分项系数无关,因此只能造成巨大的材料浪费。截面的设计破坏模式与实际破坏模式不完全一致,这种不一致现象存在的范围随着FRP筋材料分项系数的增大而扩大。Based on the data for designing concrete structures as well as the statistics of sectional geometry and the mechanical properties of the materials involved, the design formulae for determining flexural capacity of concrete beams reinforced with fiber reinforced polymers （FRP） rods are proposed firstly. Then, the Rackwitz-Fiessler method is applied to calculate the averaged reliability index of six load effect ratios for flexural capacity. After the study of the effect of the partial factors of FRP rods on the averaged index, the partial factors of 1.25 for GFRP rod and CFRP rod are suggested in the end. The reliability analysis indicates that the over-conservative partial factors of FRP rods can only result in concrete crushing in high possibility. The application of those factors would cause a great waste because the reliability level corresponding to that failure mode is almost independent of the partial factors of FRP rods. Design failure mode and actual failure mode do not always occur in unison. The range of their potential unison would increase as the partial factor of FRP rod increases.

关 键 词：FRP筋 混凝土 受弯承载力 材料分项系数 可靠指标 

分 类 号：TU377.9[建筑科学—结构工程] TU312