Integrating BIM- and Cost-included Information Container with Blockchain for Construction Automated Payment using Billing Model and Smart Contracts

Payment issues are necessary in the construction industry, often manifested by high levels of arrears and long-term payment delays. An automated payment could be a solution to speed-up the payment process after successful completions. In this paper, a framework is proposed for the automated payment via Building Information Modeling (BIM), Linked Data, Smart Contract and Blockchain technologies. Geometrical and payment-related data are stored as BIM-based linked data. Linked Data technology connects a BIM model with its related Bill of Quantities (BoQ) and Quantity Take-Off (QTO). Based on the transparency, traceability and collaboration of the Blockchain technology, an automated payment can be secured. To integrate such an information container with Blockchain for the automated payment, an additional information model called Billing Model (BM) is proposed. Thereby, each Billing Unit (BU) stores one or more construction work tasks with a related payment and a related due date. Together with the corresponding Smart Contract rules, the BM can automate payment via a Blockchain. Several aspects of improvement and further development are discussed in the end.