A simple method, named peak-load method, is proposed mination of material fracture parameters ~Jc parameter fracture model (TPFM) from the peak more distinct specimens. This method is verified and split tension tests. A quantity called specimen ........ " ......... ,…
A simple method, named peak-load method, is proposed mination of material fracture parameters ~Jc parameter fracture model (TPFM) from the peak more distinct specimens. This method is verified and split tension tests. A quantity called specimen ........ " ......... , . ....., ... ,,'"' is proposed to quantitatively distinguish specimens. differences in specimen distinction number among specimens, the more confident the results obtained by the using the peak-load method, the peak loads measured fracture tests for applying the size effect model determine ~Jc and CTODc. The relationship between in TPFM and Gr and ct in SEM is established. between the fracture models can provide appreciable research and engineering practice. 135 1 two-parameter fracture model (TPFM) (Jenq and Shah, 1985) .... LJ! ... ,L'"' .......... ..,,.,,..., two material fracture parameters K5'Jc and CTODc to charac- fracture of concrete. three-point bend beam suggested for measuring values of K5'Jc and CTODc by the test initial compliance and the compliance at the load must be measured. Therefore a closed-loop testing machine to record versus crack mouth opening displacement loading and unloading. ow1eve~r- a closed-loop test system may not be available in many and Thus Tang, Ouyang and Shah (1995) have r"'t'tf"•r"C'""',, a simple procedure to determine K5'Jc and CTODc from peak three or more distinct specimens. This method is named method to distinguish it from the test method recommend- RILEM, which is t:alled compliance method. In this paper, a is proposed as a measure of confidence level for K5'Jc and determined by peak load method. Based on it, another called specimen distinction number is proposed to distinguish the sense the proposed method. With the peak-load ............. , .......... ...., .......