Constitutive modelling to predict behaviour of PCC mixes with tire derived aggregates

Abstract

Due to the worldwide depletion of raw materials required for construction projects, it is becoming clear that alternative and renewable construction materials are needed to reduce the demand for raw materials. Sound concerns arise from the side effects of replacing normal aggregate with tire rubber waste, which is expected to affect mechanical properties of the Portland Cement Concrete (PCC) mixes. To be able to decide on suitable Tire Derived Aggregates (TDA) replacement percentages, a simplified model is proposed to predict the PCC mixes stress-strain diagram with different TDA percentages. 0, 10, 20, 40, 60, 80 and 100% TDA were investigated. Using homogenization and lab test results for PCC mixes, 0% and 100% TDA were used as upper and lower bounds, and a model was developed to predict Young’s moduli and stress-strain curves for evaluated PCC mixes. Then the model results were verified using other test results. It was found that the proposed model seems to capture the behaviour of PCC mixes with TDA fairly well. However, peak stress for PCC mixes with 40% TDA results were slightly underestimated, but with reasonable accuracy. Furthermore, the proposed model well predicted the ultimate stresses, ultimate strains, and the elastic modulus.