Sensor-integrated hybrid blockchain system for supply chain coordination in volumetric modular construction

Volumetric modular construction (VMC) needs streamlined supply chain coordination to achieve its full potential benefits, such as reduced schedule and cost, with consistent quality. Studies have noted that blockchain technology has significant potential for increasing the efficacy of supply chain coordination by providing reliable information sharing among VMC stakeholders. However, it is not well known how blockchain technology's enhanced information sharing ultimately can lead to better supply chain coordination in VMC. To address this issue, we developed and tested a blockchain-based information collecting, storing, and sharing system with an automated contract execution method. A sensor-integrated decentralized application collects project information and sends it to the blockchain network to be shared among project participants for data-driven actions in VMC. We demonstrated the system through a hypothetical case project in which stakeholders took photos with their mobile devices to share the module's status information to trigger an automated payment promptly, facilitating efficient supply chain coordination. The results show that any photos collected from the stakeholder's mobile device can be traceably stored and shared in the suggested blockchain system regardless of their file size, triggering nearly real-time automated payments. The primary contribution of this study is the development and demonstration of a blockchain system that realizes accountable project-related information sharing with automated contract execution functions across VMC stakeholders for better supply chain coordination.