During implementation of construction projects, durations of activities are affected by various factors. Because of this, both during the planning phase of the project as well as the construction phase, managers try to estimate, or predict, the length of any delays that may occur. Such estimates allow for the ability to take appropriate action in terms of planning and management during the execution of construction works. This paper presents the use of the non-deterministic concept for describing the uncertainty of estimating works duration. The concept uses the theory of fuzzy sets. The author describes a method for fuzzy estimations of construction works duration based on the fact that uncertain data is an inherent factor in the conditions of construction projects. An example application of the method is presented. The author shows a fuzzy estimation for the duration of an activity, taking into consideration the distorting influence caused by malfunctioning construction equipment and delivery delays of construction materials.
The complexity of construction projects increases the likelihood of hazards affecting their successful implementation. There are many risk factors that lead to the failure of the project. These factors should be identified and ordered both because of their degree of importance (significance) and level (volume) of a given factors. This is very important in order to determine their effect on the construction project. Typically, the threats for the construction project include the extension of the project duration, the increase of the project cost and/or the reduce of the quality of the works. This article aims (1) to identify risk factors that may affect the construction project in Poland in the above-mentioned aspects and (2) to prioritize the significance of those risk factors. Due to the uniqueness of individual construction projects, the potential hazards and their effects are usually characterized by different levels of uncertainty. Unfortunately, it is often a non-statistical uncertainty. For this reason, the degree of significance of risk factors is described and modelled using linguistic variables and elements of the theory of fuzzy sets. This method allows to evaluate the risk of construction projects prior to their implementation.
Article deals with the problem of technology selection for construction project. Three criteria were proposed: cost, time and technological complexity. To solve the problem, fuzzy preference relations were used. Authors present an algorithm supporting multi-criteria decision-making process. The algorithm creates fuzzy preference relations on the basis of the fuzzy comparison: "xi is better than xj". Then, with the use of criteria weights it creates general fuzzy preference relation, finds all non-dominated (admissible) alternatives and the best one among them. The algorithm consists of 7 steps. Authors show application of the proposed algorithm -example calculations.
In the construction practice, at the stage of planning of a construction project, planners are trying to take into account the possibility of unfavorable situations and their consequences during the project execution. Therefore, planning decisions should use appropriate tools for uncertainty modeling as well as consider alternative options for the implementation of the entire undertaking or the most sensitive (critical) works. Taking into account the fact that the management and planning of construction projects is carried out in conditions of non-stochastic uncertainty, the authors propose to create an alternative model with a fuzzy decision node based on classical network models. This approach allows to model activities that are alternative to each other. An important methodological element is the fuzzy assessment of the considered alternatives with the use of fuzzy set theory. The proposed alternative network model with a fuzzy decision node gives the possibility to conduct a comprehensive analysis with the possibility of taking into account and modeling the uncertainty of input data in an easy way. The numerical example shows the possibility of quick selection of the best variant based on the adopted assessment criteria and allows to serialize work variants, which gives additional information in the alternative activities of the network model in the form of preferences. The combination of a decision model in the form of a decision node with a network model can be useful in both strategic and tactical planning of the implementation of construction projects.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.