Complexity of Construction Supply Chain Management: Agent-Based Simulation of High-Rise Building Construction Project

Abstract

(2) in the case that insufficient resources are shared by multiple material supply process, the interference between those processes can occur unpredictably and have a negative effect on a whole construction project, even in Just-In-Time method that is able to optimize the inventory level of individual process

(3) spatial conflicts between workspace and internal material storage space can have a negative effect on a whole supply chain, which is irregularly circulated in the form of feedback between construction and material supply processes

(4) in construction projects that have the complex behaviors as above, holding the minimized inventory level in Just-In-Time results in lower performance due to lack of safety inventory that can alleviate the nega-tive effects of the complex behaviors. However, holing an excessive inventory level also exhibits lower performance because the complex behaviors increase with the increase of the inventory level. Thus, the relationship between the inventory level and the performance of construction projects is not linear

finally, (5) as the external risk factors can changes the behaviors and relationship of system components, the relationship of the inventory level and the performance of construction projects is not constant, but changeable.

The main contribution of this research is to extend a body of knowledge by investigating the complex behaviors of construction sup-ply chains and their impact on the performance of construction projects, which are difficult to explain though the previous researches based on reductionist perspectives.

Based on reductionist perspective, existing researches on construction management have focused on individual components of construction projects under the assumption that those components are independent with each other and the relationship of the input and output of each component is linear. However, production systems of construction projects are complex systems whose components are interdependent and generate emergent effects that is difficult to explain with the properties of individual components. Hence, previous researches with the reductionist perspective have a limitation to understand the characteristics and behaviors of whole production systems. Based on a holistic perspective in order to overcome these limitations, supply chain management regards various types of value-adding and non-value-adding activities as one process and synchronizes such processes in the light of the interdependence of components and processes, in order to maximize the performance of construction projects.

High-rise building construction projects, whose number remarkably increase in the world, are characterized by large-scale projects that are comprised of a number of organization, tasks, materials, spaces and information, and concurrent construction projects that a number of construction works are performed simultaneously. Whereas, these projects are also characterized by insufficient resources for material supply. These characteristics can make supply chains of high-rise building construction projects complex by causing various types of interactive and dynamic behaviors between construction and material supply processes. Nevertheless, previous researches on building constructions have been conducted under the reductionist perspective, and researches in the holistic perspective have made efforts to build a theoretical and research foundation, which is difficult to provide specific and quantitative in-formation on the interdependence of components and their emergent effect on a whole system.

For those reasons, in this dissertation, I conducted a series of re-searches with the purpose of identifying complex behaviors of the components of high-rise building construction projects and examining an emergent effect of a whole supply chain. Through the process to achieve this purpose, firstly, I developed a conceptual framework for construction supply chains and established five hypotheses on the complexity of them. Secondly, using agent-based and discrete-event simulation methods, I developed multiple simulation models associated with the five hypotheses. Finally, I carried out simulation experiments with real-world data in order to confirm the five hypotheses.

Through the results from simulation experiments, this research resulted in the following findings: (1) as the network of construction process is comprised of heterogeneous and locally connected components, the local effects from external risk factors such severe weather do not have a linear relationship with the performance of construction production systems