Concrete is weak in tension and strong in compression which results in brittle failure. This is obviously unacceptable for any construction materials. Thus, concrete requires some type of tensile reinforcement to balance its brittle behavior and improves its tensile strength. Adding of fibers is one of the most prevalent techniques to enhance the tensile behavior of concrete. Fiber slows cracking phenomena and increases energy absorption capacity of the structure. Majority researchers focus on mechanical performance of fiber reinforced concrete. In this research, the influence of various dosages of steel fibers (0%, 1.0%, 2.0%, 3.0%, and 4.0% by weight of cement) is investigated on the mechanical and durability properties of concrete. Mechanical properties such as compressive strength and split tensile strength are studied at 7-and 28-days curing. To evaluate the durability aspects of each mix, various parameters such as water absorption, acid attack resistance, and permeability are investigated. Results indicate that strength was increased up to 2% addition of steel fiber and then reduced gradually. It also indicates that, durability parameter of concrete for example water absorption, permeability, and acid attack resistance considerably improved with incorporation of steel fibers at 2.0% incorporation of steel fibers. Therefore, it is recommended to mix steel fibers up 2.0% by weight of cement to achieved maximum benefits.

No abstract

No abstract

No abstract

The automorphism group of the set of 12 points associated with an apolar system of conics is determined. A complete (q -&arc for q = 13 can be obtained as a special case. The orbits of its automorphism group are also described. 0 I Y Y~ John Wile?. & Sons, h e .