چكيده به لاتين
Abstract:
Changes in construction projects represent a critical challenge faced by the construction industry. Architectural, engineering, and construction projects are depicted as dynamic, unique, information-rich, labor-intensive, and risky undertakings. Typically, the lifecycle of these projects is divided into seven stages: client needs clarification, conceptual design, detailed design, construction, delivery, operation, and maintenance. Several stakeholders from various domains such as architecture, structure, mechanics, electrical, plumbing, execution, etc., play predominant roles at each project stage. Given the dynamic and challenging environment in which the construction industry operates, fluctuations and changes in construction projects significantly impact project outcomes, schedules, and costs. However, a comprehensive understanding of the various factors affecting these changes and their effects will be instrumental in improving project performance. This research investigates this issue by employing structural equation modeling to examine the causal relationships between different factors affecting changes in construction projects and their effects. It is expected that these findings and analyses will enhance the construction industry's capability in predicting, managing, and controlling changes optimally in construction projects. This study was conducted by collecting and categorizing the underlying causes and effects of changes through the Partial Least Squares (PLS) modeling technique. The Smart PLS software was used to develop and evaluate the study model based on 24 change causes and 18 change effects identified through literature review. The change causes were classified into three structured categories: client-related causes, consultant-related causes, and contractor-related causes, while effects were grouped into time, cost, and quality impacts. Survey data were collected from 384 professionals working on construction projects in contracting companies in Tehran. evaluation of the constructed model demonstrated that the client group, due to the presence of the factors "insufficient understanding of client needs" and "client collaboration with multiple contractors," with an outer loading of 0.862, is the most influential group of causes in the model. Meanwhile, the time increase effect due to the presence of the factor "disagreement between client and contractor," with an outer loading of 0.885, is the most significant parameter affected by changes occurring in construction projects in Tehran.
