BIM-INTEGRATED SYSTEM: A SUCCESSFUL ALTERNATIVE FOR ESTIMATING CASH FLOW IN BUILDING PROJECTS

Abstract

Cash flow calculation is an essential economic aspect of evaluating the success of a construction project. Strong cash flow positively impacts not only project effectiveness but also company profitability. Cash flow calculation is a good way for the contractors to avoid risks related to delay, cost overrun, or incompletion caused by financial deficits in the project’s performance. Building Information Modeling (BIM) is a revolutionary technology 4.0 that has been mandated and adopted by many countries all over the world. In Vietnam, a roadmap for BIM application in the construction sector was issued in 2023, under which obligatory new investment projects in public investment state capital provide BIM files to serve the appraisal of feasibility study reports, construction designs carried out after fundamental designs, applications for construction permits, and acceptance testing tasks. However, BIM authoring programming is still limited to cost management, especially cash flow calculations, because Vietnamese contractors are still facing a lot of difficulties in applying BIM to their projects, especially cash flow calculations. Therefore, this paper proposes a BIM-integrated system for calculating construction cash flow at the early phase of the project life cycle. The proposed system includes four modules: BIM visualization and data integration, construction cost estimating, construction project scheduling, and project cash flow calculation. The main functionality of the BIM visualization and data integration module is to provide a 3D visualized model with enough geometric and non-geometric data for the project quantity take-off. The functionality of the construction cost estimating module is to provide the direct cost categories, such as labor, material, and machine, and the indirect cost categories to perform all work tasks in the construction project. The main functionality of the construction project scheduling module is to provide the required time to complete all work tasks in the project implementation process. The main functionality of the project cash flow calculating module is to present cash inflows such as advance payment, payments from the owner, and cash outflows such as construction costs, equipment costs, project management costs, and project consultant costs to carry out the projects. The BIM-integrated system will make the calculation process of construction project cash flow easier and more accurate.