Performance of Fiber Reinforced Concrete Produced with Mineral Admixtures and Waste Plastic Fibers Under Acid Attack
In this experiment an effort is put to produce the fiber reinforced concrete by partially replacing cement with mineral admixtures like ground granulated blast furnace slag, Metakaolin and silica fume in different percentages. Along with replacing cement partially, steel fibers were also partially replaced by waste plastic fibers. This replacement would reduce the production cost considerably. Another important factor considered in this experiment is to assess the performance of the fiber reinforced concrete thus produced under acidic environment. The grade of concrete used for this study is M25. Total percentage of fibers was 2% of the volume. Keeping steel fibers as 1% and waste plastic fibers as 1% of the specimen volume, fiber reinforced concrete specimens were produced replacing cement by mineral admixtures namely ground granulated blast furnace slag, Metakaolin and silica fume in different ratios from 10% up to 25%. The specimens were immersed in acidic solution for a period of 90 days. The specimens were then checked for difference in weight and tested for compression, split tensile, shear and flexural strength and the results were compared with the conventional Fiber reinforced concrete.It was found from the investigation that the conventional concrete has the highest strength when compared with all the different samples when subjected to acidic solution and this is obvious as the control mix has the highest cement and steel fiber content. However when focused on the samples that were produced replacing steel fibers by 50% by various plastic fibers and cement by various mineral admixtures in varying percentages from 10% up to 25%, replacement of cement by ground granulated blast furnace slag shows considerably less drop in overall performance when compared with Metakaolin and silica fume. Also it can be noted that 20% is the optimum percentage replacement of cement by mineral admixtures.
Keywords - Mineral Admixtures, Flexural Strength, Split Tensile, Acid Attack, Plastic Fibers.