Abstract:
At the present time, Construction cost can be considered as one of the most important factors. This research aims to use recycle concrete as coarse aggregate. Nevertheless, no research has investigated the relationship between compressive strength and tensile strength. And Create simple estimation equations to predict compressive strength, tensile strength and density of concrete recycle. With proportions and compressive strength of recycled coarse aggregate as independent variables. Therefore, this research will study and compare the compression strength and tensile strength of concrete by using recycled concrete as coarse aggregate from concrete with ultimate compressive strength of 240, 380 and 500 ksc. Aggregate in various ratios will be compared with concrete using crushed rock as normal aggregate under the conditions that all grain sizes are in the range from 3/4 to 1 1/2 inch. With designed ultimate compressive strength of 280 ksc. using constant water to cement ratio. The ratio of crushed rock : recycled concrete used in this research are 75:25, 50:50, 25:75 and 0:100. Ten samples for each proportion will be tested for compressive strength and tensile strength. Therefore 120 samples will be tested in total. It was found that the concrete strength and Density are significantly decreased when increasing the proportion of recycled concrete as coarse aggregate.