Reducing the fingerprint of infrastructure has become and is likely to continue to be at the forefront of stakeholders’ interests, including engineers and researchers. It necessary that future buildings produce minimal environmental impact during construction and remain durable for as long as practicably possible. The use of basalt fiber-reinforced polymer (BFRP) bars as a replacement for carbon steel is reviewed in this article by examining the literature from the past two decades with an emphasis on flexural strength, serviceability, and durability. The provisions of selected design and construction guides for flexural members are presented, compared, and discussed. The bond of BFRP bars to the surrounding concrete was reportedly superior to carbon steel when BFRP was helically wrapped and sand coated. Experimental studies confirmed that a bond coefficient kb = 0.8, which is superior to carbon steel, may be assumed for sand-coated BFRP ribbed bars that are helically wrapped, as opposed to the conservative value of 1.4 suggested by ACI440.1R-15. Code-based models overestimate the cracking load for BFRP-reinforced beams, but they underestimate the ultimate load. Exposure to an alkaline environment at temperatures as high as 60 °C caused a limited reduction in bond strength of BFRP. The durability of BFRP bars is influenced by the type of resin and sizing used to produce the bars.

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Fly ash is a sustainable partial replacement of Portland cement that offers significant advantages in terms of fresh and hardened properties of concrete. This paper presents the findings of a study that aims at assessing the durability and strength properties of sustainable self-consolidating concrete (SCC) mixes in which Portland cement was partially replaced with 10%, 20%, 30%, and 40% fly ash. The study confirms that replacing Portland cement with fly ash at all of the percentages studied improves resistance of concrete to chloride penetration. The 40% fly ash mix exhibited the highest resistance to chloride penetration compared to the control mix. Despite the relative drop in compressive strength after 7 days of curing, the 28-day compressive strength of 40% SCC mix reached 55.75 MP, which is very close to the control mix. The study also confirms that adding 1%, 1.5%, and 2% basalt fibers, respectively, to the 40% fly ash mix improves the resistance to chloride penetration compared to the mix without basalt fibers.

Artificial Neural Networks (ANN) has received a great attention from researchers in previous decade to predict different aspect of engineering problems. The aim of this research is to present an implementation of ANN to predict the Chloride penetration of self-consolidating concrete (SCC), containing various amounts of cement replacement minerals including fly ash, silica fume, and slag.  The ability of concrete to resist chloride penetration is measured using Rapid Chloride Penetration (RCP) test through an experimental program. One- and two-layer ANN models were developed by controlling the critical parameters affecting chloride penetration to predict the results of RCP test.  The ANN models were developed using various parameters including ratio of water-to-binder (w/b), course aggregate, fine aggregate, fly ash, and silica fume. It was shown that the prediction accuracy of ANN models was sensitive to combinations of learning rate and momentum. Data used to train and test the ANN were obtained through an experimental program conducted by the authors.

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