چكيده به لاتين
The Persian Gulf is well known as one of the most aggressive environments in the world because of its high relative humidity, temperature and concentration of chloride ions. Improving the durability of concrete structures in such environments is an important issue. In this paper, the performance of ternary and quaternary blended mortars/concretes containing natural zeolite (NZ)/silica fume (SF) and lime stone powder as an inert filler, under various exposure conditions has been investigated. To achieve this objective, self-consolidating mortar/concrete specimens containing 15% natural zeolite, 8% silica fume with total binder content of 380 kg/m3 with a constant water to cement ratio of 0.45 were fabricated. After 7 days of curing in saturated calcium hydroxide solution, all of the specimens were subjected to three exposure conditions (tidal, splash, submerged). After taking fresh property testes of mortar/concrete samples, hardened properties were investigated by mortar/concrete compressive strength, chloride permeability, concrete electrical resistivity, mortar capillary water absorption and porosity tests. Also, the degree of sulfate attack was evaluated by measuring expansion of mortar prisms. Moreover, both the conventional and SCC mixes were subjected to these durability tests in order to compare their performance. The results were obtained from a laboratory set up and indicated that when the durability properties of the concretes in such environments were taken into account, the ternary use of zeolite and silica fume provided the best performance in all exposures. Furthermore, self-consolidating concretes and mortars performed better than the normal types. The correlation between electrical resistivity and compressive strength with sorptivity of all mixes exposed to simulated Persian Gulf sea water and costs of materials were also evaluated.
