Effects of specimen height on the acoustic emission rate value ‘a’ for cement mortar

Abstract

In order to study the size effect on the AE rate ‘a’ value, three kinds of mix ratios were set up by different particle sizes and water cement ratios, 45 cement mortar specimens with five different heights were tested under axial compression. And the whole damage processes were monitored by full-digital acoustic emission acquisition system, followed by an analysis of mechanical behavior and AE activity. The experimental results show that the height of the cement specimen has significant effects on the compressive strength and the acoustic emission rate ‘a’ value, but a slight effect on the accumulated AE hits number, which is analyzed from aspects of failure process of cement mortar specimens.

Keywords

cement mortar / concrete / acoustic emission / damage evolution / a value / rate process analysis

References

[1] Sagar RV, Prasad RV, Prasad B R, et al. Microcracking and Fracture Process in Cement Mortar and Concrete: A Comparative Study Using Acoustic Emission Technique[J]. Experimental Mechanics, 2013, 53(7): 1161-1175.

[2] Haneef TK, Kumari K, Mukhopadhyay CK, et al. Influence of Fly Ash and Curing on Cracking Behavior of Concrete by Acoustic Emission Technique[J]. Construction and Building Materials, 2013, 44: 342-350.

[3] Carpinteri A, Lacidogna G, Niccolini G. Damage Analysis of Reinforced Concrete Buildings by the Acoustic Emission Technique[J]. Structural Control and Health Monitoring, 2011, 18(6): 660-673.

[4] Saliba J, Loukili A, Grondin F, et al. Identification of Damage Mechanisms in Concrete under High Level Creep by the Acoustic Emission Technique[J]. Materials and Structures, 2014, 47(6): 1041-1053.

[5] Saliba J, Loukili A, Grondin F, et al. Experimental Study of Creepdamage Coupling in Concrete by Acoustic Emission Technique[J]. Materials and Structures, 2012, 45(9): 1389-1401.

[6] Grosse CU, Ohtsu M. Acoustic Emission Testing[M], 2008

[7] Ohtsu M. Rate Process Analysis of Acoustic Emission Activity in Core Test of Concrete[J]. Concrete Library JSCE, 1992, 20: 143-153.

[8] Ohtsu M, Watanabe H. Quantitative Damage Estimation of Concrete by Acoustic Emission[J]. Construction and Building Materials, 2001, 15(5): 217-224.

[9] Su HZ, Tong JJ, Hu J, et al. Experimental Study on AE Behavior of Hydraulic Concrete under Compression[J]. Meccanica, 2013, 48(2): 427-439.

[10] Watanabe T, Hosomi M, Yuno K, et al. Quality Evaluation of Shotcrete by Acoustic Emission[J]. Construction and Building Materials, 2010, 24(12): 2358-2362.

[11] Suzuki T, Ogata H, Takada R, et al. Use of Acoustic Emission and X-ray Computed Tomography for Damage Evaluation of Freeze-thawed Concrete[J]. Construction and Building Materials, 2010, 24(12): 2347-2352.

[12] Suzuki T, Ohtsu M, Shigeishi M. Relative Damage Evaluation of Concrete in a Road Bridge by AE Rate-process Analysis[J]. Materials and Structures, 2007, 40(2): 221-227.

[13] Ishibashi A, Matsuyama K, Ohtsu M. AE Application for Diagnosis of Deteriorated Concrete of Harbor Structures[J]. Proc. 6th Int. Sym. on AE from Composite Materials, 1998 145-152.

[14] Suzuki T, Ohtsu M. Quantitative Damage Evaluation of Structural Concrete by a Compression Test Based on AE Rate Process Analysis[J]. Construction and Building Materials, 2004, 18(3): 197-202.

[15] Carpinteri A, Lacidogna G, Pugno N. Structural Damage Diagnosis and Life-time Assessment by Acoustic Emission Monitoring[J]. Engineering Fracture Mechanics, 2007, 74(1): 273-289.

[16] Ohtsu M, Suzuki T. Quantitative Damage Estimation of Concrete Core Based on AE Rate Process Analysis[J]. Journal of AE, 2005, 22: 30-38.

[17] Qian L. Damage Evaluation of Concrete Based on Acoustic Emission Technique[D], 2005 Wuhan: Huazhong University of Science and Technology.

[18] Kani GN. How Safe are Over Large Concrete Beams[J]. Am. Concr. Inst., 1960, 56(9): 1469-1479.

[19] Cotterell B, Mai YW, Lam KY. Statistics and Size Effect in Cementitious Materials[J]. Cement and Concrete Research, 1995, 25(2): 408-416.

[20] Yang G, Hikosaka H. Crack Length and Specimen Size Influences on Fracture Strength of Brittle Materials[J]. Construction and Building Materials, 1996, 10(8): 565-570.

[21] Koc V, Sener S. Size Effect in Normal-and High-strength Concrete with Different Notches under the Axial Load[J]. Journal of Materials in Civil Engineering, 2009, 21(9): 433-445.

[22] Ince R, Arici E. Size Effect in Bearing Strength of Concrete Cubes[J]. Construction and Building Materials, 2004, 18(8): 603-609.

[23] Hu X, Duan K. Size Effect and Quasi-brittle Fracture: the Role of FPZ [J]. International Journal of Fracture, 2008, 154(1–2): 3-14.

[24] Glucklich J, Cohen L J. Size as a Factor in the Brittle-ductile Transition and the Strength of Some Materials[J]. International Journal of Fracture Mechanics, 1967, 3(4): 278-289.

[25] Wang ZY, Su XY. The Effects of Shape Factors on the Concrete Strength Grade[J]. Sichuan Building, 2006, 26(4): 144-145.

[26] Kim JK. Size Effect in Concrete Specimens with Dissimilar Initial Cracks[J]. Magazine of Concrete Research, 1990, 42(153): 233-238.

[27] Dyskin AV, Van Vliet MRA, Van Mier JGM. Size Effect in Tensile Strength Caused by Stress Fluctuations[J]. International Journal of Fracture, 2001, 108(1): 43-61.

[28] Karihaloo BL, Abdalla HM, Xiao QZ. Deterministic Size Effect in the Strength of Cracked Concrete Structures[J]. Cement and Concrete Research, 2006, 36(1): 171-188.

[29] Liu HY, Zhang JQ, Cheng SS, et al. Study on Compressive Strength of Concrete Core Samples [J]. Concrete, 2012, 2: 36-38.

[30] Ji HG, Zhang T S, Cai MF, et al. Experimental Study on Concrete Damage by Dynamic Measurement of Acoustic Emission[J]. Chinese Journal of Rock Mechanics and Engineering, 2000, 19(2): 165-168.