Preliminary experimental study on producing green building mortar by using recycled construction waste

As the resource of natural sand is exhausting while construction waste is recycled with a low rate in China, this paper aim at solving this problem by using construction waste to substitute natural sand in producing building mortar. In this study, recycled sand made of construction waste substitutes natural sand with a rate of 0, 20, 40, 60, 80 and 100% to produce cement-based mixed mortar with the strength of M5.0,M7.5 and M10. The results shows that water consumption increases, coursing degree of mortar decreases, and water-retaining capacity of mortar goes up while recycled sand is used more; recycled sand has no significant adverse influence on the strength of middle and low strength mortar, and when the substituting rate is 40%, good particle size distribution is obtained and higher strength of mortar is gained; for mortar of M5.0, M7.5, all substituting rates can meet the designed strength requirement.