الفهرس | Only 14 pages are availabe for public view |
Abstract This thesis reports new means to address these issues by introducing engineered cementitious composite (ECC), which is designed based on micromechanics principles and exhibits higher tensile and ductility, to replace brittle concrete matrix. Two series of ECC mortar mixes with two ratios of sand/cement =0.50 and 0.8, different Poly Propylene fiber content (1, 2, 3, 4%) and fly ash/cement ratios (50, 100, 150, 200%) were designed and tested. The results revealed that, ECC specimens exhibit significant increases in loadcarrying capacity, ultimate deflection capacity and damage tolerance (such as crack width or spalling) compared to those with sand/cement =0.50. The extent of improvement strongly depended on the failure mode; that is, when the limit state was dominated by the matrix behavior, more significant improvement was observed. Moreover, ECC specimens showed improvement in the flexural performance in terms of ductility, deformability and compressive strength as the fiber increased to 3.00%. Also, the experimental results revealed that the flexural behavior and ductility were improved at fly ash/ cement ratios of 100%, while the compressive strength decreased. |