Effect of recycled concrete aggregates on the flexural behavior of reinforced concrete beams

Abstract

The last few decades witnessed an increased interest in sustainable construction. Many studies suggested that construction industry has drastically contributed to the overall environmental degradation. Central to the idea of sustainable construction is the choice of construction materials. A number of studies attempted to find new materials that replace conventional ones and help in preserving the natural resources. A sustainable material is one that reduces the use of energy and eliminates the depletion of raw materials. Although nowadays there exists a number of green alternatives, these remain restricted in most cases to nonstructural components. This project aims to investigate the effects of replacing natural coarse aggregates with Recycled Concrete Aggregates (RCA). The replacement is an attempt to make concrete, the worlds most used construction material, less harmful to the environment. The lack of research on the subject is highlighted in the literature review. The project is mainly concerned with the experimental study of the flexural behavior of RCA concrete as well as the properties of aggregates used and the resulting Recycled Concrete Aggregates (RAC). Most of the findings are in conformity with the researchers results The four-point bending test was used to determine the bending behavior of two beams; used as control beam the first made beam is made entirely with natural coarse aggregates (R0).The second beam prepared a 75% replacement ratio of the coarse aggregates. The experimental program included four reinforced concrete beams. The first beam is made entirely with natural coarse aggregates (assigned R0) and three beams made with different replacement ratios of the coarse aggregates that are 50%, 75% and 100%. Our project focus on R0 and R75 while another project deals with the other two ratios 50% and 100%. So our conclusion can be drawn with regard to the flexural capacity Mn, cracking moment Mcr and deflection expectations.