Performance-based design of high performance fiber reinforced cementitious composites for repair of rigid pavement and other infrastructure

A large number of existing concrete infrastructures suffer from deterioration under combined mechanical and environmental loads and require high costs for renovation. Repeated maintenance of these structures often results in social and environmental costs. Thus, a sustainable repair material that will provide longevity with minimal maintenance is urgently needed. As a result of the studies conducted in recent years, the successful application of Engineered Cementitious Composites (ECC) in the repair and strengthening of concrete structures is observed. The objective of this study is to develop new generation ECC mixtures with high early age strength and high dimensional stability, compatible with existing concrete, and without compromising its high ductility and multiple micro-cracking behavior. This study is composed of mainly three parts: in the first step, a comprehensive literature survey was carried out on the criteria specified by national and international organizations for high early age strength for rapid repair of conventional concrete and how these criteria were obtained. In the second part, several high early age strength ECC (HES-ECC) mixtures were designed by micro-mechanical design procedures and their ductility and strength (compressive and flexural) properties were verified in accordance with the criteria specified in the first part of this study. In the third part, after testing the properties of monolithic specimens, the bond strength, flexural performance and freeze/thaw resistance of layered HES-ECC specimens (existing concrete + HES-ECC) were tested and the performances of mixtures were compared with one of the commercially available high early strength repair material.