Improving Infrastructure Performance Using BIM (Building Information Modelling): Experimental Study of Cost Reduction in Road Planning

The productivity of the construction sector still needs to be increased by choosing effective methods. Manual method (2D) road planning takes a long time and results are less accurate. BIM (Building Information Modelling) as a new method needs to be proven for use in road planning projects. In this study, the BIM method was applied to the case study of the new road planning of Kretek-Girijati using Autocad Civil 3D software. Planning includes vertical alignment and horizontal alignment with the 2021 Geometric Road Guidelines standards. Furthermore, the volume of excavation and landfill will emerge from the model and the total cost will be known after multiplying the unit price. Some planning alternatives use BIM models compared to the initial design. There are 3 alternative designs made, featuring a shorter road trace length, more sloping, less excavation volume and pile than existing routes. The cost of the existing design is IDR 28,920,870,000.00, the most economical cost in Alternative 3 is IDR 15,697,819,300.00 with the difference in the cost of both IDR 13,223,045,900.00. It was concluded that Alternative 3 is the most economical in terms of earthworks compared to other alternatives and existing designs. These findings provide a reinforcement to use BIM methods at the road design stage.