Effect of strain rate and water-to-cement ratio on compressive mechanical behavior of cement mortar
来源期刊：中南大学学报(英文版)2015年第3期
论文作者：ZHOU Ji-kai(周继凯) GE Li-mei(葛利梅)
文章页码：1087 - 1095
Key words：cement mortar; loading rate; compressive strength; critical strain; stress-strain behavior
Abstract: Effects of strain rate and water-to-cement ratio on the dynamic compressive mechanical behavior of cement mortar are investigated by split Hopkinson pressure bar (SHPB) tests. 124 specimens are subjected to dynamic uniaxial compressive loadings. Strain rate sensitivity of the materials is measured in terms of failure modes, stress-strain curves, compressive strength, dynamic increase factor (DIF) and critical strain at peak stress. A significant change in the stress-strain response of the materials with each order of magnitude increase in strain rate is clearly seen from test results. The slope of the stress-strain curve after peak value for low water-to-cement ratio is steeper than that of high water-to-cement ratio mortar. The compressive strength increases with increasing strain rate. With increase in strain rate, the dynamic increase factor (DIF) increases. However, this increase in DIF with increase in strain rate does not appear to be a function of the water-to-cement ratio. The critical compressive strain increases with the strain rate.
ZHOU Ji-kai(周继凯), GE Li-mei(葛利梅)
(College of Civil and Transportation Engineering, Hohai University, Nanjing 210098, China)
Abstract:Effects of strain rate and water-to-cement ratio on the dynamic compressive mechanical behavior of cement mortar are investigated by split Hopkinson pressure bar (SHPB) tests. 124 specimens are subjected to dynamic uniaxial compressive loadings. Strain rate sensitivity of the materials is measured in terms of failure modes, stress-strain curves, compressive strength, dynamic increase factor (DIF) and critical strain at peak stress. A significant change in the stress-strain response of the materials with each order of magnitude increase in strain rate is clearly seen from test results. The slope of the stress-strain curve after peak value for low water-to-cement ratio is steeper than that of high water-to-cement ratio mortar. The compressive strength increases with increasing strain rate. With increase in strain rate, the dynamic increase factor (DIF) increases. However, this increase in DIF with increase in strain rate does not appear to be a function of the water-to-cement ratio. The critical compressive strain increases with the strain rate.
Key words:cement mortar; loading rate; compressive strength; critical strain; stress-strain behavior
