impact of 4d modeling on construction planning process - Chalmers ...

Figure 0-11: Percent plan complete over project duration
3.3.2 Case study 2 (Kymmell, 2008)
This case study is about a contractor developing virtual design and construction
(VDC) tools and integrating them into their standard processes. The VDC program
focused on 3D quality control, 4D scheduling, and 5D cost estimation. The
contractor’s executives were convinced from the start that the VDC process will be
beneficial for them, so not much effort was paid on return on investment (ROI)
studies. Rather their focus was to design and develop standards, processes, and
infrastructure for the effective delivery <strong>of</strong> new approach and to validate results to gain
confidence in the new BIM tools. Quite early in the program phase, two points
became obvious.
A quantity estimated by constructing a model is much more reliable than one
estimated from traditional methods and 2D documents and drawings.
The time spent in creating a model replaces the time spent in taking <strong>of</strong>f
quantities from 2D documents and drawings. With proper standards, processes
and training, creating a model is as fast as extracting data from the 2D
documents and drawings. That is, the time spent is evaluating the 2D
documents equals the time in creating a 3D model which will help us visualize
the 2D documents more efficiently and precisely. Thus the 3D model can
further be used for scheduling and coordination by transforming it into a 4D
model.
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CHALMERS, Civil and Environmental Engineering, Master’s Thesis 2012:27