مدیریت مبتنی بر مدل منابع پویا برای پروژه‌های ساخت و ساز

Excess resource idling can result in cost overruns, while low resource coverage or long lead-time in resource acquisition can delay the project schedule. Therefore, systematically managing this tradeoff is critical to ensure project delivery in time and within budget. In addition, to provide practically useful guidelines and tools, the dynamic construction process needs to be realistically represented. As an effort to address these issues, a model-based dynamic approach is proposed for construction resource management. The dynamics of construction progress and the tradeoff with resource coverage are identified. Then, the dynamic resource management model that has been developed using system dynamics is described. By simulating the model with heuristic and industry data, the effect of resource coverage on project performance is quantified and policy implications are obtained for dynamic resource management. Finally, the use of the model as an automated tool is demonstrated.

Construction progress is constrained by either work availability or resource availability. Work availability at a certain progress is governed by the work dependency [1] within the same activity (‘internal work dependency’, e.g., structural steel erection on the second floor can start only after completion of the first floor work) or between activities (‘external work dependency’, e.g., a finish-to-start relationship between foundation and excavation). Since work dependencies are determined by the nature of work, they are normally beyond the project manager's control. In contrast, resource availability is more likely determined by resource plans and managerial decisions, which can be made independent of the construction system. This fact suggests that construction management is nothing but resource management. For this reason, most project management text books (e.g., [2], [3], [4] and [5]) recognize resources as the key to meeting a project schedule, addressing their significant impact on the construction system. In the same context, the importance of resource management has been emphasized in the literature [6], [7], [8] and [9]. Various methods and formulations have been also suggested for effective resource management. For example, Padilla and Carr [10] developed a simulation model to dynamically allocate given resources to construction activities. Karaa and Nasr [6] and [19], and Senouci and Adeli [9] and [11] proposed mathematical formulations to optimize resource utilization. The models developed by Chan et al. [12] demonstrated that model-based resource leveling and constrain-based scheduling are useful in shortening project duration. For the same purpose, comprehensive algorithms and neural dynamic models were also elaborated [7], [8] and [13]. These researches demonstrated how resource-driven planning could enhance project performance and contributed to establishing a basis for construction resource management. Despite their different views and approaches, the previous researches commonly focused on minimizing resource idling and waste. As will be discussed, excess resource idling and waste can result in cost overruns, while low resource coverage or long lead-time in resource acquisition can delay the project schedule by creating resource bottlenecks. Therefore, systematically managing this tradeoff at either planning or control stages is critical to ensuring project delivery is in time and within budget. In addition, to provide practically useful guidelines and tools, the dynamic construction process needs to be realistically represented. In this paper, a model-based dynamic approach is proposed for construction resource management. Following a brief introduction of system dynamics, the research methodology, the dynamics of construction progress and its determinants are discussed. Then, having identified the tradeoff associated with resource coverage, and work dependencies involved in construction, this paper describes the dynamic resource management model developed using system dynamics. By simulating the model, it examines the effect of resource coverage on project performance and obtains policy implications for dynamic resource management. Finally, it is demonstrated how the model supports their application as an automated tool.

A model-based dynamic approach for construction resource management was proposed. Having identified the dynamics of construction progress and the tradeoff with resource coverage, this paper discussed the dynamic resource management model developed using system dynamics. By simulating the model with heuristic and industry data, the effect of resource coverage on project performance was quantified and policy implications were obtained. Then, the use of the model as an automated tool was demonstrated. Although the research results should be further refined and validated with more industry-linked researches, the model-based dynamic approach presented in this paper would have the following potential impacts: • Enriching the construction knowledge base by (1) introducing a new view on construction progress (work-constrained progress vs. resource-constrained progress), (2) identifying the time and cost tradeoff between resource coverage and project performance, and (3) representing the feedback based dynamic construction process. • Enhancing project performance by (4) providing a dynamic management tool to systematically manage resource coverage and other construction settings, and (5) improving construction professionals' understanding on the construction system.