The influence of age on Double-K fracture parameters of roller-compacted concrete (RCC) was investigated via fracture test on eighteen RCC wedge splitting specimens at different ages (28 d, 60 d, and 90 d). The effective crack length, initial fracture toughness and unstable fracture toughness of the RCC specimens of different ages were acquired. Results revealed that with the growth of age, the critical pressure for initial cracking and critical pressure for instability both expanded, and the ratio of critical pressure for initial cracking to critical pressure for instability also increased. With the age increasing from 28 d to 90 d, initial cracking toughness KiniIC and unstable cracking toughness KunIC climbed by 0.216 0 MPa·m1/2 and 0.292 2 MPa·m1/2, respectively; the ratio of KiniIC to KunIC maintained between 0.5 and 0.6 in general. Effective critical cracking length and subcritical crack extension both changed in a negative relation with age, implying that smaller age results in better toughness of specimens.
Key words
roller-compacted concrete /
double-K fracture parameters /
age /
wedge splitting test /
fracture toughness
{{custom_sec.title}}
{{custom_sec.title}}
{{custom_sec.content}}
References
[1] 胡少伟, 谢建锋, 喻 江. 不同初始缝高比楔入劈拉试件断裂试验研究[J].长江科学院院报, 2015, 32(2): 114-118.
[2] 张国辉,李宗利,聂抗义,等.不同含水率混凝土断裂韧度试验研究[J].水力发电学报,2016,35(2):109-116.
[3] 胡少伟, 胡 亮. 混凝土试件四点加载剪切断裂试验研究[J].长江科学院院报, 2014, 31(9): 99-104.
[4] 陈 晋. 非标准楔入劈拉试件研究混凝土的断裂参数[D].大连:大连理工大学, 2009.
[5] 张小刚, 王学志, 陈意勤, 等. 缝高比及尺寸对碾压混凝土失稳断裂的影响[J].深圳大学学报(理工版), 2011, 28(2):125-130.
[6] 赵 超. 不同再生粗骨料掺量碾压再生混凝土楔入劈拉试验研究[J].结构工程师, 2015, 31(1):132-136.
[7] LIU C, ZHANG H, L N. Influence of Different Sizes of Concrete and Roller Compacted Concrete on Double-K Fracture Parameters [J].2016, 10(35): 500-508.
[8] 王学志, 毕 重, 张小刚, 等. 碾压混凝土断裂韧度尺寸效应的试验研究[J].武汉理工大学学报, 2007, 29(6):54-57.
[9] BAANT Z P, OH B H. Crack Band Theory for Fracture of Concrete[J].Matériaux et Construction, 1983, 16(3): 155-177.
[10] HILLERBORG A, MODER M, PETERSSON P E. Analysis of Crack Formation and Crack Growth in Concrete by Means of Fracture Mechanics and Finite Elements[J].Cement and Concrete Research, 1976, 6(6): 773-781.
[11] JENQ Y S, SHAH S P. Two Parameters Fracture Model for Concrete[J].Journal of Engineering Mechanics, ASCE, 1985, 111(10): 1227-1241.
[12] KARIHALOO B L, NALLATHAMBI P. Effective Cracks Model for the Determination of Fracture Toughness (KIce) of Concrete[J].Engineering Fracture Mechanics, 1990, 35(1/3):637-645.
[13] BAANT Z P, KAZEMI M T. Determination of Fracture Energy, Process Zone Length and Brittleness Number from Size Effect, with Application to Rock and Concrete[J] .International Journal of Fracture, 1990, 44(2): 111-131.
[14] XU S, REINHARDT H W. Determination of Double-K, Criterion for Crack Propagation in Quasi-brittle Fracture, Part II: Analytical Evaluating and Practical Measuring Methods for Three-point Bending Notched Beams[J].International Journal of Fracture, 1999, 98(2):151-177.
[15] 徐世烺. 混凝土断裂力学[M].北京:科学出版社, 2011: 232.
[16] DL/T 5332—2005,水工混凝土断裂试验规程[S] .北京:中国电力出版社,2006.
[17] 胡少伟, 范向前, 陆 俊. 强度等级对混凝土双K断裂参数的影响[J].水电能源科学, 2012,(9):77-81.
PDF(2104 KB)
