Rework is one of the most commonly encountered issues that face construction projects, leading to potential loss of money and delays. The aim of this study is to investigate the potential role of Building Information Modelling (BIM) in reducing Client-Related Rework (CRR) when set within the context of fast-track construction projects in Egypt. In order to study this issue survey data was collected from 51 construction professionals within the Egyptian private construction sector with experience in fast-track projects through a self-administered questionnaire composed of fourteen closed and open-ended subgroup of questions, whose aim is to gain an understanding of the main sources of CRR in the industry. The survey results revealed that the majority of the respondents (92.1%) had experienced CRR in construction projects, resulting in an average project cost increase of 22% and an average delay of 23%, as well as formulating the basis for a novel Severity Index (SI), which was devised in order to rank CRR causes, with its finding revealing "Clients' financial problems", "Impediment in prompting the decision making of the client" and "Replacement of materials by the client", as the biggest contributors to CRR. The survey also highlights visualization as a potential solution to CRR, with eight case studies from literature as well as one from the Egyptian market being used to validate the use of BIM in the reduction of CRR. Findings illustrated that the use of BIM in the Egypt is similar to findings in literature, with BIM resulting in rework cost and schedule reduction of 49 and 57 percent respectively.

Water scarcity is a global issue that is rapidly worsening. Many researchers have explored various approaches to promote sustainable uses of water, with Greywater (GW) recycling and utilization of innovative plumbing fixtures being among the methods presented to reduce freshwater consumption for domestic usage. Nonetheless, previous studies have dealt with both means independently, without studying the integrated effect of utilizing both GW recycling and innovative plumbing fixtures together both on the quality of supplied water, as well as on the cost of the integrated system. Accordingly, this research aims at improving the efficiency of water usage in residential buildings through the development of a mathematical optimization model that utilizes a constructed database in order to select the most appropriate GW recycling system, plumbing fixtures and system components with the aim of improving the water quality, minimizing the water usage and reducing the cost. The developed model is divided into three main modules: input, water flow and annual worth quantification. The model was verified on a case study, and sensitivity analysis was performed to explore the impact of changing major input factors on the total annual cost. A factorial design examining both two- and three-factor interactions was used. The number of residents and the annual increase in water tariffs factors had the most significant impact on the total annual worth, accounting for 55% and 43.7% of the total variability, respectively. Furthermore, the model was validated by comparing its results with a previous study conducted in the United Kingdom, where the developed model presented a significant reduction of the lifecycle cost of the decentralized water system in residential buildings and attained freshwater savings of 58.17%.

Existing buildings consume a large portion of the total current energy production, especially in developing countries such as Egypt. Increasing energy demand, coupled with decreasing availability and increasing cost of conventional non-renewable energy resources, have encouraged a “building green” retrofit trend in order to maximize the energy performance of the built environment. This paper outlines the development of an Energy Retrofit Decision-Support System (ERDSS) for hot, arid climates that models building retrofit scenarios and determines the impact of each retrofit measure on the overall energy consumption of a proposed building retrofit program. The methodology combines building an energy simulation with a database-driven, budget-constrained optimization framework based on the Savings-to-Investment Ratio (SIR) to evaluate and prioritize retrofit measures. In addition, ERDSS determines the impact of each retrofit measure on the overall energy consumption of a proposed building retrofit program, ranks the retrofit measures according to their Savings-to-Investment Ratio (SIR) and uses optimization to develop a suggested retrofit program for a given budget. ERDSS is applied on a case study of an education building in New Cairo, Egypt, in order to illustrate the performance of the framework. Results show that savings for the commissioned retrofit, standard retrofits, and deep retrofits reached 15 percent, 35 percent, and 45 percent, respectively.

Expansion joints (EJ)s are considered one of the weakest elements in bridges as their lifetime is considerably shorter than that of other elements. The objective of this research was to select an appropriate system for assessment and maintenance of bridges’ EJs. The system seeks to predict the conditions of EJs, with the aim of offering appropriate maintenance and repair strategies that extend their life spans. An EJ management system (EJMS) was developed that optimizes cost over time, targeting the optimum maintenance strategy for EJs, through visual inspections and a genetic algorithm to construct a unique Markov chain transition matrix capable of predicting EJ deterioration. The model was tested using case studies of existing bridges in Egypt and the results were compared against visual inspection, with the comparison showing deviations between 3.2% and 8.1%. The EJMS can help decision makers in selecting the optimum maintenance strategy that maximizes the overall conditions of EJs while meeting budgetary constraints.

This paper presents a detailed life cycle assessment (LCA) of a Dynamic Sand Filter continuous upflow sand filtration system used in municipal and industrial wastewater treatment. This study evaluates the environmental impacts associated with raw material extraction, manufacturing, transportation, operation, and end-of-life disposal. Using the TRACI methodology and following ISO 14040/44 standards, the results indicate that operational energy use, primarily electricity consumption, is the dominant environmental contributor, accounting for over 99% of total Global Warming Potential (GWP). Comparative analyses demonstrate that Dynamic Sand Filter outperforms conventional Dynamic Sand Filtration Methods (DSFMs) in both energy and emission efficiency across multiple wastewater treatment scenarios. The findings emphasize the environmental advantages of continuous filtration systems and highlight opportunities for further optimization through renewable energy integration and eco-design improvements, with the technology presenting savings of over 40 percent lower CO₂ per cubic meter in operational emissions and over 25 percent lower overall energy consumption. Additionally, this research includes further comparison with conventional Rapid Sand Filters and simulated suggestions to enhance ecological footprint.