Effect of Silpozz and Fly Ash on Strength and Durability Properties of Concrete in Sea Water

This paper investigates the influence of using environmental by-product materials such as Silpozz and Fly Ash (FA) in concrete properties to resist saline water. The mix design is targeted for M30 grade concrete. Five concrete mixtures were designed to have the same degree of workability with water to cementitious material ratio of 0.43. The plain cement concrete samples made 0% replacement of FA and Silpozz with cement. The blended cement concrete samples made with 10% replacement of FA and 10%, 20%, 30%, and 40% replacement of silpozz with cement. Two set of samples (cube, cylinder and prism) have been prepared. One set of sample, after 28 days of Normal Water Curing (NWC) was being immersed in sea water for 7, 28 and 90 days and the other set of samples have been cured in normal water for 7, 28 and 90 days. The studied parameters include the compressive strength, flexural strength and split tensile strength of NWC and Sea Water Curing (SWC) samples after 28 days of NWC for 7, 28, and 90 days curing period. The acid soluble chloride and water soluble chloride contents were measured through the concrete samples of 28 days SWC after 28 days of NWC. The obtained test results indicated that the use of FA and Silpozz in concrete showed significant resistance to chloride penetration up to 10% replacement of FA and 30% replacement of Silpozz with cement. The carbonation depth of concrete samples for 90 days SWC after 28 days of NWC was measured. There is no significant change in depth of carbonation. The percentage increase in compressive strength for blended cement concrete in NWC is better than the samples in SWC after 28 days of NWC.