Effect of Strain Gradient on Tensile Strength of Concrete Blocks

The tensile strength of the masonry unit is an important characteristic affecting the capacity of concrete block masonry under various loading conditions. Therefore it is necessary to have some measure of the tensile strength of the block that is both reliable and representative of its strength in the stress field associated with the loading conditions. The tensile strength was observed to vary considerably depending on the stress field created. From tests of concrete blocks under concentric axial tension, eccentric axial load, flexural tension, and splitting tension, it was shown that the tensile strength is significantly affected by the strain gradient. A linear relationship between the tensile strength and the strain gradient was proposed based on experimental data. It is suggested that this relationship could be used in the analysis of masonry assemblages where tension is the governing failure mode.