Influence of water-retaining cellulose ethers on the properties of bedding mortar used in concrete structural masonry

The aim of this study was to investigate the influence of water-retaining cellulose ethers agent on the bedding mortar in concrete structural masonry. Hydroxypropylmethyl cellulose (HPMC) was used in different proportions in a cement-lime based mortar (0.00%, 0.03%, 0.06% and 0.09% of the total dry weight) to evaluate the influence of cellulose ethers on the properties of mortars in the fresh and hardened states. In addition, prisms were produced from three concrete blocks and mini-prisms were sawed off concrete blocks to evaluate compressive strength, modulus of elasticity and bond strength. The results showed that there is potential in the use of water-retaining cellulose ethers agent in the bedding mortar of concrete structural masonry, since that there was an increase in the water retention capacity of the mortars and the use of these products did not influence the compressive strength of the mortar and the masonry prisms. However the compressive strength of the bedding mortar joints, the modulus of elasticity of the prisms and the bond strength in flexion were significantly reduced, when cellulose ether was used.

Water-retaining agent; Cellulose ethers; Bedding mortar; Structural masonry; Concrete blocks.