Durability and service life design concepts for structures and (non-)structural members made of or strengthened/repaired with SHCC

Abstract

Due to their unique properties, strain-hardening cement-based composites (SHCC) are well-suited for structural and non-structural members, as well as for the repair and rehabilitation of ordinary concrete structures that are exposed to severe mechanical or environmental loading. To fully utilise their advantageous durability properties, a comprehensive durability and service life design framework is required. This framework must encompass design concepts for all relevant load cases and load case combinations. For an efficient service life design of members and structures, the design concepts must be performance-based. In this chapter, SHCC applications and relevant degradation processes are classified. Following the classification, possible service life design approaches are described, categorised and assessed regarding their suitability for the service life design of SHCC members and structures. Following an outline of a possible development strategy for a service life design framework, available design concepts for chloride-induced rebar corrosion are presented. It is shown that in order to develop available concepts into a comprehensive durability design framework, the uncertainty of input variables must be reduced, and deterioration models must be further validated. Finally, other limit states, load cases, and load case combinations must be considered. Moreover, it is postulated that for most load cases and load case combinations, suitable deterioration models for SHCC with reasonably well-quantified input variables will require significant additional development. Hence, deterioration model-free durability assessments with fuzzy uncertainty quantifications will likely be the most suitable option for most load cases and load case combinations for the foreseeable future.