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Time–space conflicts are one of the most common issues facing construction practices, impacting safety and productivity in several negative ways at construction sites. Therefore, implementing and developing methods to reduce the frequency of such conflicts occurring in activity workspaces can effectively enhance project performance. Space is usually a constrained resource in construction project sites; therefore, in this project, we propose an approach as a method of time–space conflict management in construction project sites. The method implements Informed Rapidly Exploring Random Tree-Star (Informed-RRT*) path planning, Discrete Event Simulation (DES), and geometry to automatically detect and resolve time–space conflicts in construction projects. To evaluate the method's capabilities, it is tested on a case study of an earthwork operation, including the loading, hauling, dumping, and return phases. Finally, our method finds the shortest travel path and duration for each hauling truck between two given starting and end points in each phase without colliding with static obstacles (randomly placed in the site), intersection points of the trucks' path, the start and stop time for the truck serving higher-priority construction activities, and the total duration of each truck's earthwork operation. [ABSTRACT FROM AUTHOR]

The problem of selection or ranking of alternatives based on multiple criteria is not an easy problem, neither economically nor mathematically. The recent advancements in various structural systems have made the selection of the appropriate structural system for a specific project a challenging decision-making process. This process involves different economic and technical criteria representing the availability of experienced technicians and engineers and necessary machinery and construction materials. Economic life cycle, environmental protection related issues, safety of the project site, and vulnerability to natural disasters such as earthquakes are also issues related to the country and location in which the construction project takes place, and they should also be addressed in the decision-making process. In this paper, a new algorithm combining two well-known multicriteria decision-making (MCDM) techniques, namely, elimination and choice expressing the reality III (ELECTRE III) and preference ranking organization method for enrich evaluation II (PROMETHEE II), have been specially developed for ranking of structural systems. The proposed algorithm is also applicable to group decision-making cases. In addition, the decision matrix data, criteria weights, preference, indifference, and veto thresholds are set as interval values to consider uncertainties in the decision-making procedure. The proposed methodology considers veto threshold, provide complete ranking, exempts the preference functions and includes conceptions such as risk, uncertainty, and reliability with interval approach. The proposed algorithm has been utilized in selecting the appropriate structural system in a low-rise multihousing project in Iran. In this case study, sixteen criteria have been used to select the best structural system between eight alternatives considering relevant uncertainties in the judgments of three groups of stakeholders (owner, consultants, and contractors). The results of the case study showed that the proposed methodology can be used as a proper tool for decision making in the construction management processes. [ABSTRACT FROM AUTHOR]