Abstract Interim payment provisions in construction projects are susceptible to unfair practices. In construction project participants with varying financial capacities belonging to different organizations are bound by contractual relationships. Due to this type of project organizational structure, project participants do not completely trust each other which prevents the adoption of existing centralized automated frameworks for interim payment. Therefore, this paper presents a distributed blockchain-based framework that does not require to be trusted for automatically enforcing the terms and conditions related to interim payments and sharing payment records at project-level transparently and securely. A logic to automatically initiate, validate, and disburse interim payments according to general contract conditions for interim payments is formalized in this paper. A blockchain-based data model that enables selective-transparency in payment records is proposed. This data model facilitates the sharing of sensitive financial information privately between two contracting parties and non-sensitive payment-related information publicly among all project participants. The proposed blockchain-based framework is supported by a key management strategy to facilitate different security properties such as confidentiality and authenticity of data and users. Considering the non-technical nature of construction project participants, the proposed key management strategy is designed to dynamically generate cryptographic keys from publicly sharable parameters so that storage and management overheads are reduced. Security properties such as immutability, data confidentiality, user integrity, performance, and cost of deployment of the proposed blockchain framework are validated and recommendations for executing the proposed framework with a high level of security are discussed in this paper.

中文翻译：

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通过基于区块链的框架确保建设项目的临时付款

摘要 建设项目中的临时付款条款容易受到不公平做法的影响。在建设项目中，属于不同组织的具有不同财务能力的参与者受到合同关系的约束。由于这种类型的项目组织结构，项目参与者之间并不完全信任，这阻碍了采用现有的集中式自动化框架进行临时支付。因此，本文提出了一种基于分布式区块链的框架，该框架不需要被信任，可自动执行与临时支付相关的条款和条件，并在项目级别透明、安全地共享支付记录。自动启动、验证、并根据一般合同条件支付临时付款，在本文中正式确定了临时付款。提出了一种基于区块链的数据模型，可实现支付记录的选择性透明性。该数据模型有助于在两个缔约方之间私下共享敏感的财务信息，并在所有项目参与者之间公开共享非敏感的支付相关信息。提议的基于区块链的框架由密钥管理策略支持，以促进不同的安全属性，例如数据和用户的机密性和真实性。考虑到建设项目参与者的非技术性质，提议的密钥管理策略旨在根据可公开共享的参数动态生成加密密钥，从而减少存储和管理开销。验证了安全属性，例如不可变性、数据机密性、用户完整性、性能和所提议的区块链框架的部署成本，并在本文中讨论了以高安全级别执行所提议框架的建议。