Micromechanics-based design of strain hardening cementitious composites (SHCC)

Abstract

This paper reviews the research and development of micromechanics-based design theory of strain hardening cementitious composites (SHCC) at different scale, linking the microstructure at micro scale with the composite tensile behavior at macro scale through fiber bridging properties at meso scale. Micromechanics relates macroscopic properties of SHCC to its microstructures, and forms the theoretical basis of SHCC design theory. So the single fiber pullout behavior at micro level lays the foundation of the scale-up research and has been investigated under various loading conditions. Based on the single fiber pullout behavior, analytic tools on micromechanics-based strain hardening model have been developed in closed or numerical forms. And it is widely applied as design guideline in guiding ingredients selection and component tailoring to achieve desired strain hardening performance. Afterwards, the micromechanics-based concept has been extended to develop models for tensile stress-strain properties and cracking process of SHCC. Therefore, the micromechanics-based design methodology of SHCC becomes holistic in the sense of obtaining the ultimate composite behavior with given micromechanical parameters, and versatile in various SHCC design, i.e. towards durability performance with charactering the crack pattern. It is expected that the micromechanics-based design tools capable of capturing the essence of SHCC behavior, should help structural designers take full advantage of SHCC material in infrastructure system design.