Comparative testing of crack formation in strain-hardening cement-based composites (SHCC)

Two of the main activities of RILEM Technical Committee 208-HFC Subcommittee 2 were the preparation and publication of the state-of-the-art report on durability of strain hardening cement-based composites (SHCC), and the performance of comparative laboratory testing on SHCC. In this paper the comparative mechanical tests are reported, as performed in laboratories of five participating institutions. The purpose was to investigate and compare the crack patterns in terms of crack widths and spacing, and subsequently to make recommendations for a suitable test setup and procedure towards characterizing cracking in this class of materials. Such standardized procedures are required for future systematic and objective research towards durability of these materials in their in-service conditions, i.e. their resistance to deterioration processes in the cracked state. Standardized test procedures are also required for durability testing and guidelines for structural design with SHCC, which is the focus of follow-up committee activity in TC 240-FDS.