Influence of Crumb-Rubber in the Mechanical Response of Modified Portland Cement Concrete

Abstract EN

The influence of crumb-rubber on the mechanical properties of Portland cement concrete (PCC) is studied by experimental tests and numerical simulations.

The main hypothesis of the study is that replacing part of the stone aggregate with crumb-rubber in the mix modifies the energy dissipation during the cracking process and affects the concrete behaviour under monotonically increasing loads.

The experimental research program characterizes the mechanical properties of PCC for three different types of concrete with a variable content of crumb-rubber.

The experimental results showed that fracture energy and other properties are directly related to the rubber fineness used in the mixture.

The material properties derived for these laboratory tests are used to study, by numerical models, its response through its damage evolution.

The numerical model used to simulate the damage evolution of the concrete is the Embedded Discontinuity Method (EDM).

One characteristic of the EDM is that it does not need to modify the mesh topology to propagate the damage through the continuum solid.

For this study, the Disk-Shaped Compact Tension specimen geometry, normed by the D7313-13 of the ASTM, is used.

Results showed that the numerical methods provide good approximation of the experimental curve in the elastic and softening branches.