Essay Example on The details of mix proportions used in this Research

The details of mix proportions used in this research are given in Table 1 Ordinary Portland cement type I with high grade 52 5N and silica fume SF were used as cementitious materials The chemical compositions and physical properties of the cementitious materials used are listed in Table 2 For all test specimens a W C of 0 18 was applied Sand with grain size smaller than 0 6 were used Natural crushed basalt graded from 1 18 mm to 10 0 mm max nominal size was used as a coarse aggregate To improve fluidity a high performance water reducing agent Sikament NN super plasticizer SP was added to investigate the effect of steel fiber volume fraction and aspect ratio on the mechanical properties steel fibers with a length of 30 mm and a diameter of 1 0 mm and steel fibers with a length of 50 mm and a diameter of 1 0 mm were considered in three different volume fractions 0 1 2 and 3 with aspect ratios 50 and 30 leading to seven series of test specimens The properties of steel fiber are presented in Table 3 The test specimens were cured at clean tab water for 28 days Compression test The compression test was carried out on cube specimens 100 100 100 mm and cylinders with 100 mm diameter and 200 mm height after 28 days curing 

The flexural strength was calculated as follows was conducted on 100 x 100 x 500 mm prism specimens The specimens were demoulded after 24 hours of casting and were transferred to curing tank where in they were allowed to cure for 28 days ASTM C 1018 Using a Beam with Third Point Loading was used to determine the flexural strength This test consists of loading a small prism at the third points to create a constant moment region and recording the load and deflection so the data can be analyzed to give the flexural cracking stress flexural strength of the fiber reinforced concrete This configuration loaded the specimens at the third points of the span and created a simple support condition as outlined in ASTM C 78 where the specification for the loading apparatus is given The deflection measuring was secured to the prism at the neutral axis of the prism directly above the support points In each category three beams were tested and their average value is reported The flexural strength was calculated as follows