Cascaded and upgradable smart contracts for blockchain-aided construction business process management

Collaboration in Construction Business Process Management (CBPM) often suffers from inefficiency, fragmentation, and security concerns. Blockchain and Smart Contract (SC) offer potential solutions by enabling automation, transparency, and tamper-resistant records. However, adoption remains limited due to two critical gaps: (1) insufficient automation, as current SCs lack cascaded (interdependent) execution, and (2) insufficient adaptability, as existing SCs are non-upgradable, limiting responsiveness to workflow changes. This paper proposes a SC-CBPM framework addressing these gaps through three objectives: (1) Automate CBPM tasks and processes; (2) Develop Cascaded SCs to link interdependent tasks and enforce access control; (3) Develop Upgradable SCs to allow updates without data loss. The framework is validated through two scenarios: BIM-based design collaboration and payment automation, demonstrating feasibility and acceptable computational workability. Performance is evaluated through gas consumption and latency, ensuring deployment readiness. The main contribution is advancing blockchain from a static record-keeping tool to an adaptive workflow automation mechanism.