Effect of Water Content on Tensile Properties of Cement Mortar

Abstract

In order to study the effect of water content on the tensile properties of cement mortar, the “8” test method was used for the five water contents of the two mix ratios (saturation was 0%, 25%, 50%, 75%, and 100% respectively.) A total of 100 cement mortar specimens were subjected to a uniaxial tensile test. The test results show that the stress-strain curves of the cement mortar specimens are similar under different saturation, and the stress increases nonlinearly with the increase of the strain. After the peak strain is reached, the specimens are destroyed. The curve has no yield stage and shows the characteristics of brittle materials of the cement mortar; As the saturation increases, the tensile strength, peak strain and fracture toughness of the cement mortar specimens first decreased and then increased, and showed a linear relationship; the cement with a saturation of 50% mortar specimens have the lowest tensile properties. Compared with cement mortar samples with saturation of 0%, the tensile strength, peak strain, and fracture toughness were reduced by 40%, 24%, and 50%, respectively; the peak strain of cement mortar specimens with 100% saturation was the largest. The cement mortar specimens with a saturation of 0% increase by 24%; by comparing the tensile properties of cement mortar specimens at two different mix ratios (water-cement ratios of 0.55 and 0.45, respectively), it was found that the water-cement ratio was not the same. The effect of saturation on the tensile properties of cement mortar is similar, verifying the accuracy of the test results.