Strain Resilient Cementitious Composites of Unclassified Calcareous Fly Ash and PP Fibers: Performance by also Considering Durability Effects: Fid-Bau Portal

Strain Resilient Cementitious Composites of Unclassified Calcareous Fly Ash and PP Fibers: Performance by also Considering Durability Effects

Tastani, Souzana / Ntampanli, Evangelia / Savvidis, Ioannis / Veneti, Maria / Zapris, Vasileios

Abstract

Abstract Strain Resilient Cementitious Composites (SRCC) is a class of ECCs, following the design philosophy in terms of grain fineness of mixing materials and the high dosage of plastic fibers, but differentiating in the tensile response: after first cracking they develop a wide parabolic response sustaining adequate tensile strength up to high levels of strain. The material’s deformation is concentrated near a limited number of cracks emanating from the anchorage conditions of the embedded fibers. In the case of SRCC made by the less studied calcareous fly ash (of low pozzolanic ingredients and high lime) and polypropylene (PP) hydrophobic fibers, early studies have shown that strong chemical bond links are developed in the fiber-binder interface as the material hardens with time. This time-dependent effect alters the mechanical behavior of fibers from partial pullout at early age to elongation at advance time; the latter mechanism promotes the occurrence of early crack stabilization with the development of few cracks which sustain the tensile resistance due to the sufficient anchorage length of the fibers. This paper presents experimental results for the mechanical characterization of four SRCCs with parameters the Greek calcareous fly ash and the PP fiber contents at advanced age. In total 120 specimens were tested in compression (cubes) and tension (3-point bending prisms and 4-point bending beams for definition of material’s tensile strength/fracture energy and deformation capacity respectively) by also considering assessment of materials’ durability in regards to the impact of hearing and freeze-thaw cycling.