中文摘要：

采用边界效应理论,研究了断裂韧性和拉伸强度对材料与结构破坏的影响。边界效应模型中通过引入等效裂缝,可同时反映试件前边界与后边界对断裂特性的影响;基于等效裂缝与特征裂缝的比值,即可判断试件处于强度准则、韧度准则或准脆性断裂等何种破坏模式。边界效应模型不仅适用于线弹性断裂条件,而且适用于弹塑性断裂分析,解决了ASTM规范及RILEM规范的局限。鉴于ASTM规范确定材料断裂韧度对试件初始缝长与试件尺寸等的严格限制,本文基于边界效应理论,建立了由RILEM规范中小尺寸试件确定材料断裂韧度与拉伸强度的方法,相关试验成果证明了所提方法的合理性与适用性。

英文摘要：

Based on the Boundary Effect Theory,the effect of fracture toughness and tensile strength onfracture of material and structure were studied. The equivalent crack ae is introduced in Boundary EffectModel（BEM）,by which two separate boundary measurements are effectively combined into a single andunified boundary measurement. Based on the ratio of equivalent crack to characteristic crack ae/a＊∞,the frac-ture control mode such as strength criteria,fracture criteria and quasi-brittle fracture,can be determined.BEM can be applied in LEFM and elastic-plastic fracture analysis,and the limit scope of application ofASTM standard and RILEM standard has been solved by BEM. Given that ASTM strict limitations to deter-mine fracture toughness such as initial crack length and specimen size and others,a method for determin-ing fracture toughness and tensile strength according to small specimen of RILEM was proposed. The reason-ability and applicability of the proposed method has been confirmed by test results analysis.