Willawong Bus Depot Civil Works The Civil Group of BCC City Design works closely with - but separately from - the "Survey Section" of BCC who produce land surveys in-house. They produce surveys and pass them to Civil Group as DTM (Digital Terrain Model) 3D data. This data goes into the 12d Model3 system - a string- or vectorbased system “like AutoCAD and then strings can be turned into points or vertices (strings become invisible but points can be seen)”. To quote the 12d Model’s website, the system “is powerful surveying, terrain modelling & civil engineering software. It allows fast production in a wide variety of projects including mapping, site layouts, road, rail and highway design, residential & land developments, and environmental impact studies”.
Figure 4.
Impression of refuelling area of Bus Depot
Image courtesy of City Design, B r i s b a n e 20 0 8
According to a civil designer for Willawong Depot, 12d has been available for many years (he has been using it since 1999) and Queensland Department of Main Roads have taken it on as a major surveying system. Anecdotes from other users who are "into the software" has led to the belief that 12d was more flexible and reliable than most competitive packages. In his opinion, “12d is very flexible and can handle thousands of points and has no trouble with very large projects - even on 3
12d Solutions Pty Ltd
see http://www.12d.com/model/
standard computers” reportedly because it uses complex algorithms which have been refined over a long period of time. The Bus Depot itself is a number of buildings set upon a concrete slab, and because of the complex nature of the Willawong site and the important requirements for retention of rainwater and recycling of run-off and grey-water via bio-filtration drainage swales etc. there was close cooperation between the landscape design staff and the civil designers and engineers. 3D CAD capabilities were used to set up the levels for the Bus Depot and a TIN (Triangulated Irregular Network) data file was created which went back to the civil engineers “to check that it all tied in with their kerb levels and so forth - this provided a level of checking and any discrepancies were worked out between the groups”. Unfortunately from a full BIM and interoperability viewpoint, this data was exchanged as data files rather than being an integral part of a synchronous BIM system. In the Willawong Bus Depot project, it seems that the civil designer was never requested to take any data into Revit, so the interface or interoperability between 12d and Revit was not explored in the project.
Landscape Design In this project, when viewed from a multidisciplinary team perspective, the edges between the disciplines were somewhat blurred with civil engineers responsible for kerb levels and also pathways (traditionally a landscape component) while landscape architects were responsible for courtyard areas and similar. With a focus on innovation and sustainability for the Bus Depot project, BCC landscape architects provided criteria to the service consultants about where lightpoles etc. should NOT be
CRC for Construction Innovation, BIM National Guidelines and Case Studies Project (2007-02-EP)
Case Study 5 Page| 5 of 11