Design of structures made using Silica Fume (SF) concrete to an acceptable level of safety requires the probabilistic evaluation of its mechanical properties. An extensive experimental program was carried out on compressive strength, flexural strength and tensile splitting strength of SF concrete. Seven concrete mixes with different proportions of SF were designed to produce 490 concrete samples. The probabilistic models to describe the variability of the mechanical properties of SF concrete were proposed. Two parameter probability models such as Weibull, normal, lognormal and gamma distribution were considered for the representation of variability. The probability distribution models were selected based on the three goodness-of-fit tests such as the Kolmogorov-Sminrov (KS), Chi-square (CS) and log-likelihood (LK) tests.The results obtained from the models are useful for description of the variability of selected mechanical ManuscriptClick here to access/download;Manuscript;Manuscript.docx 2 properties of SF incorporated concrete. This study proposed lognormal distribution function as the distribution model that most closely describes the variations of different mechanical properties of SF concrete for a practical point of view. Further, the performance of typically selected buildings using SF concrete was evaluated through fragility curves and reliability indices incorporating the proposed probability distributions and variability of compressive strength property. It was found that 15% to 25% of partial replacement of cement with SF may yield better performance of the frames.

Sustainable concrete construction has encouraged the utilization of industrial wastes (fly ash, silica fume, ground granulated blast furnace slag, metakaolin, etc.) as a composite cementitious material due to its high pozzolanic activity. Among them, fly ash (FA) concrete is gaining high popularity in the construction industry due to its several benefits to the concrete structures with increased structural performance. In order to estimate the seismic performance of FA concrete buildings, a probabilistic study needs to be performed for its mechanical parameters at various performance limit states. Weibull, normal, log-normal and gamma distribution probability distribution models are considered for three goodness-of-fit tests such as the Kolmogorov-Smirnov (KS), Chi-square (CS) and log-likelihood (LK) tests. Among them, the lognormal distribution is found to be the closest distribution in describing the variations in the mechanical properties of FA concrete as compared to other distributions. It was observed that 20% to 40% partial replacement of FA with cement gives an improved performance to the structures with enhanced structural safety at economical cost.

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.

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