FRACTURE PARAMETRIC STUDY ON CEMENT-BASED MATERIALS FROM THREE-POINT BENDING TEST
For two most basal cement-based materials, cement paste and mortar, their fracture parameters were studied by 84 geometrically similar three-point bending beams of which strength and size were varied. Complete load versus crack mouth opening displacement (PCMOD) curves were directly obtained, and their fracture toughness were determined. In the test, a sudden brittle fracture was not found in cement paste and an apparent stable crack propagation before unstable failure was observed both in cement paste and mortar. The process of crack initiation, stable extension and unstable failure were investigated using resistant strain gauges. There exist obvious size effects both in the critical crack mouth opening displacement and critical crack tip opening displacement of cement paste and mortar. Due to the influence of shrinkage crack and the precritical crack propagation length, the initial fracture toughness KIc ini and unstable fracture toughness KIc un are not size-independent.
Shilang Xu Yu Zhu
State Key Laboratory of Coastal and Offshore Engineering, Dalian University of Technology, Dalian China.
国际会议
第九届工程结构完整性国际会议(The Ninth International Conference on Engineering Structural Integrity Assessment)
北京
英文
2007-10-15（万方平台首次上网日期，不代表论文的发表时间）