A New Perspective in the AEC Industry
1910! A solid 99 years to the present, Henry Laurence Gantt, an American mechanical engineer designed a chart popularly called Gantt chart, named after him, to monitor progress of the project against time constraint. It has long been a popular technique for project planning. But it lacks something to be desired when it comes to visualizing a project timeline. 4D model is the solution to it. 4D model is a 3D CAD model attached to the fourth dimension of time via a schedule. Though the concept of 4D scheduling has been around over 20 years, it has not been popular due to some technical challenges associated with it. The continuous advancement in technology and the emergence of Building Information Modeling (BIM) have removed all challenges associated with 4D scheduling. With the increasing success of BIM in the realm of designs, the adoption of 4D modeling is becoming the norm today.
Rich with information, BIM modeling services deliver architects a wealth of design-centric tasks and home builders a number of significant benefits including increased coordination, constructability analysis, BOQ, quantification, and cost estimation and so on. One of the most important developments in building applications for BIM is the project planning where design and construction come together. At the core of a project planning, there lies building design, the backbone of a project planning. 4D scheduling plays an important role in project planning.
It includes vital data such as start and finish date of each component and their criticality. 4D model delivers minute details to the project team. It works as a platform for project team and other non-technical stakeholders to visualize the assembling of a building over time. With 4D construction simulation process, architects can evaluate various options and choose the best alternative at project design phase.
4D Modeling Offers Significant Benefits over 3D Modeling
4D model is a further development over 3D model. It challenges and changes many of the practices of conventional scheduling. Some of the significant considerations are as follows:
Visualization of the Project: 4D model enables the scheduler to view the entire construction site in a nutshell. The scheduler is able to move around, look outside, inside and under the building and verify the progress of project. It helps the scheduler to detect inconsistency and avoid visual incongruities in the representation.
Better Integration and Cost Estimation: Integrating human resources, equipment and material resources with the BIM model, 4D scheduling helps to better schedule and cost estimate of the project. 4D BIM also monitors procurement status of project materials.
Conflict Detection and Resolution: During design and construction phase, potential spatial conflicts may arise between building components. It is not easy to identify or predict these conflicts using 2D or 3D layouts. But, 4D model identifies various issues related to space, schedule and sequencing, and resolve them ahead of the construction process.
Improved Time Management: Integrated with BIM modeling, 4D scheduling helps the owner as well as project team to easily visualize time constraints and opportunities of improvement and investment in the project.
Maximization of Critical Resources: 4D model allows the project team to evaluate various alternatives resources and scopes of work over a period of time to optimize the resources and labor accordingly.
4D Project Planning with BIM
By adding the schedule date to the model components, project team improves the plan and integrates the communication among various divisions. With the progress of time, project team programmatically links schedule to BIM model to evaluate various construction options to make the optimum decision. There are two methods for linking a BIM model to a project plan-
1. Direct link between Revit and MS project, and
2. Exporting a Revit BIM and displaying it in 4D
