a. s. j. al-zuheriy

Supporting sustainable development, contributing to reducing waste that causes environmental damage, and reducing the use of natural materials are part of preserving the environment and society. This is done by highlighting the manufacture of sustainable concrete pavement of acceptable quality and according to specifications. The authors previously produced a concrete pavement mixture with optimal properties by partially replacing the Portland cement with 55 wt.% of the ground granulated blast furnace slag (GGBFS) in addition to partially replacing the virgin aggregates with 30 wt.% of recycled aggregate from crushed rigid pavement. The goal of this research work is to produce a self-sensing rigid pavement mixture from wastes with high mechanical properties, that is better than regular concrete and less expensive. The new novel mixture has the ability to detect earlier the damages that occur to the concrete pavement so as to obtain a longer life by periodically maintaining the pavement on time. The previous mixture was improved by adding chopped steel shaving fibers with lengths ranging from 20-60 mm in four different volumetric ratios. These are 0.7%, 1%, 1.1%, and 1.2%. The results were compared with those of the basic mixture, and a decrease in workability and slump values were noticed. Moreover, significant improvements in the mechanical properties were obtained. The concrete's resistance to the applied loads increased by increasing the percentage of steel shaving in the mixtures, due to the increasing of cohesion forces within the mixture. The self-sensing capability for the developed mixtures was tested by measuring the changes in the electrical resistance under different types of mechanical loadings. The results showed that the direction of the applied load and the proportion of steel shavings affect the self-sensing properties in terms of the fractional variation in the electrical resistance (FVER, %), which highlights the importance of using steel shavings in producing smart concrete pavements from reused resources more efficiently and highly cost-effectiveness.

The Strut-and-Tie modeling (STM) technique represents an applicable and valuable method for structural engineers to design disturbed regions (D-regions) of reinforced concrete structures where the assumption of plane sections remaining plane after loading is inapplicable. The most important aspect to guarantee the suitable structural and economic performance of the design is finding a suitable truss-analogy model, leading to the use of a more efficient model in structural buildings. The evaluation of the antisymmetric Strut-and-Tie models (STM) with openings under different concentrated external loads has not been comprehensively investigated in the literature. So, to address this gap, the goal of this paper is to achieve the most efficient reinforcement layout design in antisymmetric reinforced concrete deep beams with openings under concentrated loading using the strut and tie model.  The experimental work was conducted and included (3) antisymmetric reinforced concrete deep beams with openings that were tested under different concentrated loadings (25, 35, and 16 kips for Specimens 1, 2, and 3, respectively) using the strut and tie model. The ANSYS FEM software is used for the initial strut and tie analysis, and the RISA-3D structural analysis program is used to find the internal forces for all members under concentrated external loads in each specimen. The findings of this paper show that Specimen 1 had the highest efficiency of 1.67, while Specimen 3 had the lowest efficiency of 1.31. It can be concluded that the efficient reinforcement layout of the strut and tie model leads to the highest efficiency of the model, regardless of the value of the externally applied load.

The literature and previous research revealed that reducing the variation order by selecting the favorite material visually by the project's owner in the design stage is not available recently. As a problem, the cost estimates in real-time from walk-through interactions selecting multi-alternative building components are a potential threat to projects' success unless there is a visualization system helping to decide the costs of different building items and the items’ suitability. This research is a powerful tool that allows the project's owner to reduce the variation order by visually selecting his favorite material in the design stage. It expresses the application of Building Information Modeling (BIM) with Virtual Reality (VR) to improve Cost Estimation (CE) and the material selection process. The authors utilize BIM and virtual reality technology to enhance the visualization and processing of project cost estimation in the construction industry. In this study, the primary goal is to develop a BIM-VR-CE system that helps construction stakeholders to visualize and quickly to decide the costs of different building items and the items’ suitability. Accordingly, the authors developed a BIM-VR-CE system that integrates BIM and virtual reality technology using Unity 3D. Navigating building environments in real-time with the ability to select the cost and items suitable for elements of projects is now available to construction stakeholders through the BIM-VR prototype developed in this paper. To evaluate the effectiveness of the proposed preliminary model, a questionnaire was created, and 85 evaluations were collected. The findings of this paper show significant potential to utilize the proposed model in construction projects to deal with cost, reduce the variation orders, and select the favorite elements.

A conventional stirrup is widely used in all concrete beams as shear reinforcement to prevent shear failure that happens suddenly and unexpectedly without previous warning. It is a great challenge to figure out another type of stirrup and establish a new formula to calculate the deflection. This article offers an experimental study that predicts a novel formula for calculating deflection in concrete beams reinforced with shear steel plates as a stirrup. The experimental work was established and consists of 16 wide reinforced concrete beams with 216x560x1800 mm dimensions. Instead of the conventional reinforcing stirrups, steel plates with 3.0, 4.0, and 5.0 mm thickness in longitudinal and transverse dimensions and for one-half of the samples, recycled PVC round bubbles were used as the variables explored in this study. In addition, the variables include an examination of the opening form of shear steel plates with varying distances between them. For calculating the deflection of wide beams, a new formula for the effective moment of inertia is proposed, and it yields excellent agreement for several investigations, with a coefficient of variation of 5.48 percent. The formulae for calculating the maximum deflection are established using ACI 318M-14 and EC 2.