脆性基多孔材料孔洞的尺寸效应及其破坏模式研究

A study on hole size effects and failure mode of brittle materials containing multiple holes

运用材料真实破坏过程分析系统RFPA2D,对含多孔的脆性材料进行单轴加载情况下的破坏机制以及孔洞的尺寸效应研究。其中的数值模型具有同样的尺寸(高×宽=65mm×100mm)、同样的孔洞分布类型、同样的孔隙率(20%)、不同的孔洞直径。数值计算的结果显示,各种孔径的模型具有近似的抗压强度,并且可以观察到没有裂纹局部化的拉破坏模式。结果表明,含孔脆性材料的近似脆性行为并没有引起材料的尺寸效应。

A numerical analysis has been conducted to study hole size effects and failure mechanism of brittle materials containing multiple holes under uniaxial compression loading, by using the Realistic failure process analysis code （RFPA2D）. Numerical model specimens with same sizes（heightvwidth = 65 mm× 100 mm） , same periodic holes patterns, same void fraction （20 %） and different diameters holes have been numerically analyzed. The numerical calculation results show that the similar compressive strengths for the specimens are obtained. Moreover, a specimen tensile failure mode with no cracks localization has been observed, which allows us to conclude that there is no size effect engendered by the quasibrittle behavior of the considered brittle materials containing multiple holes.