The development of self-compacting concrete (SCC) is a revolutionary landmark in the history of the construction industry. Incorporation of fibres further enhances the properties, especially those related to the post-crack behaviour of SCC. The fibres used in the study are 12 mm long chopped glass fibre, carbon fibre and basalt fibre. The volume fractions of fibre taken are 0·0, 0·1, 0·15, 0·2, 0·25 and 0·3%. The research comprised two stages: the first stage consisted of the development of an SCC mix design of M30 grade; in the second stage, different fibres, such as glass, basalt and carbon fibres, were added to the SCC mixes and their fresh and hardened properties were determined and compared. Carbon fibre-reinforced SCC (FRSCC) exhibited the best performance followed by basalt FRSCC and glass FRSCC in the hardened state, whereas it exhibited the poorest performance in the fresh state due to its high water absorption. Glass FRSCC exhibited the best performance in the fresh state. This study concludes that, in terms of overall performance, optimum dosage and cost, basalt fibre is the best option for improving the overall quality of SCC.

No abstract

No abstract

Synopsis Results of tests on 20 two-span un bonded prestressed concrete I beams failing infiexure and shear under symmetrical point loads are presented. Under shear failure, the mechanism offailure being that of diagonal tension cracking only, a fracture criterion suitable for concrete is adopted to predict this cracking strength. Various existing methods of predicting the cracking strength of pre-tensioned and post-tensioned I beams are compared with the present proposal.

This study aimed to determine the strength and chloride content of marine concrete if fly ash and silica fume were used to replace a portion of the conventional Portland cement (OPC). The study was done so that these goals could be reached. W/C of 0.42 to make M30 grade concrete. Even though the number of parts that go into making OPC concrete is the same, using SP cuts the amount of water needed to make mixed concrete by 20%. Several different experiments that were done with different mixtures back up this conclusion. Compressive strength, flexural strength, and split tensile strength are the three types of strength that have been looked at. For the durability test, water-soluble chloride (WSC) will be used. SEM, which stands for scanning electron microscopy, will be used for the microstructural analysis. According to the test results, the compressive strength of concrete that had been treated with dosages of SP and had 10% fly ash showed a degradation factor (DF) of less than 5% after being exposed to the elements for a year. Even though the concrete had been out in the weather, this was still the case. After 90 days, both the split tensile strength and the flexural strength have a DF of 0.95 percent, but the flexural strength only has a DF of 0.5 percent.