Experimental Study On Mix Proportion And Compressive And Tensile Strength Of Recycled Concrete

Being service life or requirement of urban development, a great deal of concrete buildings, constructions are demolished to produce lots of abandoned concrete, more than two thirds among which is aggregate of sand and stone. The aggregate within the abandoned concrete (mainly denoting coarse aggregate) being utilized can not only reduce resource being exhausted and natural geology and geomorphic being disrupted because of extracting sand and stone aggregate, relieve the contradiction of supply and demand, but also alleviate the pollution of the environment by abandoned concrete, its economic, social and environmental effects will be quite obvious. Therefore, circulating to utilize the abandoned concrete (i.e. the new technique of recycled concrete) is getting more and more attention from lots of countries, being a hot point concerned by the engineering circles and academic circles at home and abroad and one of frontier researching topics. In this paper, the mixture ratio of recycled concrete and its fundamental mechanics properties have been researched by experiments, including: the calculating formulae and simplified calculating formulae for unit water use of recycled concrete, the trial approaching of unit water use of coarse aggregate recycled concrete, the decision of regression coefficients within Bolomey formula for coarse aggregate recycled concrete, the decision of regression coefficients within Bolomey formula for full recycled aggregate concrete, summing up the designing method for recycled concrete mixture ratio and comparing it with that for common concrete mixture ratio, cubic concrete compressive strength and split-tension strength of concrete, some factors influencing the recycled concrete strength and the laws of its strength with age developing.