This paper presents the experimental results of five large-scale hybrid glass fiber reinforced polymer (GFRP)-steel reinforced concrete continuous beams compared with two concrete continuous beams reinforced with either steel or GFRP bars as reference beams. In addition, two simply supported concrete beams reinforced with hybrid GFRP/steel were tested. The amount of longitudinal GFRP, steel reinforcements and area of steel bars to GFRP bars were the main investigated parameter in this study. The experimental results showed that increasing the GFRP reinforcement ratio simultaneously at the sagging and hogging zones resulted in an increase in the load capacity, however, less ductile behaviour. On the other hand, increasing the steel reinforcement ratio at critical sections resulted in more ductile behaviour, however, less load capacity increase after yielding of steel.The test results were compared with code equations and available theoretical models for predicting the beam load capacity and load-deflection response. It was concluded that Yoon's model reasonably predicted the deflection of the hybrid beams tested, whereas, the ACI.440.1R-15 equation underestimated the hybrid beam deflections. It was also shown that the load capacity prediction for hybrid reinforced concrete continuous beams based on a collapse mechanism with plastic hinges at mid-span and central support sections was reasonably close to the experimental failure load.

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Construction projects are usually associated with several challenges owing to the varying process during the project lifetime. Hence, the final cost of any civil engineering project is influenced by many factors. There are numerous ways of determining the final cost of a project, however, the most essential approach is the Estimate at Completion (EAC) technique. This technique is mostly favored because it considers the probability of risks and project performance. Furthermore, EAC helps project managers in the definition and determination of the critical problems expected during the project period and the likely solutions toward these problems. In this review research, the basic empirical, regression and advanced soft computing methodologies adopted for the EAC computation, were surveyed and reported in detail. The review established on the base to recognize the modern advancement of the soft computing in computing the EAC with accurate, reliable and robust manner. The review was highlighted the main literature limitation, current status and possible future direction.

A conventional Portland cement can be considered as the most consumed energy material, since it isresponsible on about 1.35 billion tons annually, occupying is approximately 6% of global CO2 emissions. It can be stated that the emission related to CO2 is the main reason of global warming and greenhouse effect. For this reason, studies have been devoted to find a clean source of material to be an alternative for the traditional cement. Geopolymer concrete is being emerged as a promised construction material that acts as an ecofriendly material. Geopolymer is an inorganic material that can be produced from geological origin or by-product waste, mainly from Silicon (Si) and Aluminum (Ai) in addition to the alkaline activator required for geopolymerization process. Research conducted to assess the performance of the existing design guidelines (e.g. ACI code) for moment and/or deflection calculations of Geopolymer concrete beams is scarcely available in literature. Therefore, this research is devoted to evaluating the applicability of ACI 318-2019 code for flexural and deflection calculations. For this purpose, a total of 40 simply supported geopolymer concrete beams embedded with steel reinforcement bars were compiled from different sources of literature. The experimental results collected from the samples were compared to those calculated by ACI 318-2019 in terms of moment capacity and deflection. It was found that the calculated moments of the ACI were conservative with a mean value and the variation of coefficient of 1.16 and 15 %, respectively. On the other hand, the deflection results were much lower than those measured experimentally. Essentially after the formation of the first crack, highlighting the need of a suitable model for precisely predicting the flexural strength and deflections of geopolymer concrete beams to reflect the main parameters that control the behavior of such elements.