A failure criterion for brittle and quasi-brittle materials under any level of stress concentration

摘要：

In this paper, we present a new criterion to predict the crack initiation under quasi-static loads from a geometrical weakness presenting an arbitrary stress concentration in brittle or quasi-brittle materials. Three material parameters were used in the establishment of the criterion, namely the ultimate stress σc. The critical energy release rate for crack growth Gc and the critical energy release rate for fracture under uniform uniaxial tension Gu. The use of these two critical energy release rates was justified by the observation of the fracturesurfaces under different stress concentrations. The proposed three parameters concept enables to take the different stress concentration levels into account, thus provides a unified criterion to predict crack initiation for any stress concentration, whatever it is singular or regular. Numerous experimental studies were selected to verify the accuracy and efficiency of the criterion. It was shown that the proposed criterion is physically reasonable,highly accurate and easy to apply. It can be used in crack initiation prediction of engineering structures made of brittle or quasi-brittle materials.

关键词： Non-singular stress concentration Fracture criteria Crack initiation PMMA Brittle quasi-brittle materials Size effect

作者: X.B.Zhang J.Li

作者单位: Blaise Pascal University of Clerraont II.laMI.France University of Paris XIII.LPMTM,CNRS UPR 9001.France

会议类型: 国际会议

会议名称: The Eighth International Conference on Fundamentals of Fracture(ICFF VIII)(第八届断裂基础国际会议)

会议地点: 香港·广州

会议语种:英文

页码: 4925-4932

在线出版日期: 2008-01-03（万方平台首次上网日期，不代表论文的发表时间）