Full-Text Search:
Home|Journal Papers|About CNKI|User Service|FAQ|Contact Us|中文
《Engineering Mechanics》 2017-12
Add to Favorite Get Latest Update

BOUNDARY EFFECT FRACTURE MODEL FOR CONCRETE AND GRANITE CONSIDERING AGGREGATE SIZE

GUAN Jun-feng;WANG Qiang;HU Xiaozhi;BAI Wei-feng;JIANG Bin;School of Civil Engineering and Communication, North China University of Water Resources and Electric Power;School of Mechanical and Chemical Engineering, University of Western Australia;School of Materials science and Engineering, University of Science and Technology Beijing;  
The application of boundary effect model(BEM) and size effect model(SEM) on fracture behavior of materials were compared. A theory and the associated method for determining the material constants(fracture toughness K_(IC) and tensile strength f_t) were proposed using experimental peak loads P_(max) from three-point-bend(3-p-b) specimens with quasi-brittle fracture controlled. The ratio of 3-p-b concrete specimens size W to maximum aggregate size d_(max) under laboratory conditions is around 5 to 20. These concrete specimens are heterogeneous, where quasi-brittle fracture is dominant. In contrast to the fracture mechanical models those are based on continuum mechanics and applied to quasi-brittle fracture, the maximum aggregate size d_(max) was introduced in the analytical formula of the proposed fracture model. The stable crack growth corresponding to the peak load of these specimens can be evaluated based on parameter combination β · d_(max), and precisely predict results can be obtained by using different values of discrete number β. The validity of the theory and the proposed method has been confirmed by test results from different scholars, including mortar, concrete and granite material(d_(max)=1.2 mm to 40 mm), linked with same specimen size W but with different initial crack length α_0 and geometrically similar or with a same ratio of initial crack length to specimens size α_0/W but different W.
【Fund】: 国家自然科学基金项目(51779095 51679092);; 澳大利亚国家基金项目(DP0346198);; 郑州市科技攻关项目(153PKJGG111);; 河南省高等学校青年骨干教师资助计划项目(2013GGJS-084)
【CateGory Index】: TU528
Download(CAJ format) Download(PDF format)
CAJViewer7.0 supports all the CNKI file formats; AdobeReader only supports the PDF format.
©2006 Tsinghua Tongfang Knowledge Network Technology Co., Ltd.(Beijing)(TTKN) All rights reserved