Compressive and Tensile Strength Characteristics of Masonry Mortars

摘要

The investigation presented was a study of the nature of strength relationships to mortar mixtures of varying water-cement ratios. Moist curing of the mortar specimens significantly increased their ultimate compressive and tensile strengths. Moist curing of the mortar specimens produced a higher percentage increase in the compressive strength of the mortar cubes than percentage increase in the tensile strength in the mortar cylinders. The tensile strength of the moist cured mortars was approximately 10% of the compressive strength. Tensile strength can also be stated to be 7.0 square root of F sub mc for the moist cured specimens. Both compressive and tensile ultimate strengths take a sharp decrease if the watercement ratio of a mortar mixture is increased from 0.4 to 1.0. This would present a critical area for watercement ratio control. In order to obtain high compressive and tensile strengths in mortars, low water-cement ratios are needed and from the standpoint of economy and efficiency, it may prove advantageous to establish some type of mortar mixture control during field preparation of mortar mixtures. In addition, the photoelastic analysis of the diametral compression load test of the mortar cylinder specimens proved to yield very satisfactory qualitative results and to a lesser degree quantitative results.