Construction Payment Automation Using Blockchain-Enabled Smart Contracts and Reality Capture Technologies

TL;DR

This paper introduces a blockchain-based smart contract system integrated with reality capture technologies to automate and improve construction payment processes, increasing transparency and reducing reliance on intermediaries.

Contribution

It presents a novel approach combining smart contracts, BIM, and UAV/UGV data for autonomous construction payment management, demonstrated on real projects.

Findings

Automated payments processed for 7 subcontractors

Enhanced payment frequency and transparency

Successful integration of UAV/UGV data with blockchain

Abstract

This paper presents a smart contract-based solution for autonomous administration of construction progress payments. It bridges the gap between payments (cash flow) and the progress assessments at job sites (product flow) enabled by reality capture technologies and building information modeling (BIM). The approach eliminates the reliance on the centralized and heavily intermediated mechanisms of existing payment applications. The construction progress is stored in a distributed manner using content addressable file sharing; it is broadcasted to a smart contract which automates the on-chain payment settlements and the transfer of lien rights. The method was successfully used for processing payments to 7 subcontractors in two commercial construction projects where progress monitoring was performed using a camera-equipped unmanned aerial vehicle (UAV) and an unmanned ground vehicle (UGV) equipped with a laser scanner. The results show promise for the method's potential for increasing the frequency, granularity, and transparency of payments. The paper is concluded with a discussion of implications for project management, introducing a new model of project as a singleton state machine.