Evaluation of the effects of engineered cementitious composites (ECC) plasticity on concrete pavement performance

Engineered Cementitious Composites (ECC) are considered a promising alternative for the construction of durable pavements. The objective of this study was to evaluate the effects of plasticity and flexural fatigue behaviour of ECC on pavement performance. A low-cost ECC using low fibre content (1.5% volume fraction), locally-available river sand and a high level of cement replacement with class F fly ash (75% by weight) was investigated. The ECC demonstrated a pseudo-strain-hardening (PSH) behaviour at all curing ages. Furthermore, as curing progressed, the tensile and flexural strengths increased; yet, ductility decreased. The flexural fatigue performance of the ECC was significantly superior to that of regular concrete. Finite Element Analysis (FEA) was integrated with flexural fatigue experimental results to establish a thickness vs. cycles to failure (T-N) relationship. In developing the T-N relation, the effect of ECC plasticity was accounted for by proposing a stress equivalency function to convert plastic stress into an equivalent linear elastic stress. From the T-N curves, it was determined that the original ECC T-N curve (without implementing the stress equivalency function) greatly overestimated the numbers of the cycle to failure for thicknesses below similar to 60 mm as this curve starts exhibiting an asymptotic behaviour with respect to N.

Automated summary

Engineered Cementitious Composites (ECC) show promising plasticity and flexural fatigue behavior, making them suitable for the construction of durable pavements. The ECC demonstrated a pseudo-strain-hardening (PSH) behavior and superior flexural fatigue performance compared to regular concrete. By integrating Finite Element Analysis (FEA) with experimental results, a thickness vs. cycles to failure (T-N) relationship was established, leading to improved accuracy in predicting failure cycles for ECC at various thicknesses.