T. Kanda and V. C. Li
Journal of Advanced Concrete Technology, 4(1) 59-72, 2006
Engineered Cementitious Composites (ECCs) have
recently demonstrated their high performance with pseudo strain hardening (PSH) behavior
in civil engineering structures and buildings. These ECCs incorporate low cost fibers
like Polyvinyl Alcohol fibers which often involve fiber rupture in composites. Such
fiber rupture type ECCs tend to have inferior and unsaturated PSH behavior compared
with properly designed pull-out type. The present study focused on presenting practical
criteria to achieve designing saturated PSH behavior in fiber rupture type ECCs.
These criteria were proposed based on two performance indices, which are measures
of energy exchange during steady state flat crack propagation and stress level to
initiate micro-cracks. The latter performance index necessitated a new cracking strength
prediction theory, which was proposed in the current study. Finally the cracking
strength theory was justified using tensile test data, and the criteria were proposed
based on the data in terms of these two indices.
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