Revit: Cut and Flood not Cut and Fill

Scott White and Hookins have recently invested in purchasing and training of its staff in the use of Autodesk Revit which is a Building Information Modelling (BIM) application.

BIM is a term that has been around for a while in manufacturing and engineering industries. In the construction sector it is a process that has started to emerge in the last five years or so. Now a mainstream technology, BIM applies the parametric 3D modelling approach to dynamic building design, adopting its principles from manufacturing and engineering design software to increase productivity.

BIM involves much more than simply switching to a new software package. It requires a different way of thinking which requires a move away from traditional workflow methods, with more time being spent on the scheme at feasibility, and outline design phases.

BIM works best when Architects, Mechanical & Electrical and Structural Engineers are all sharing the 3D parametric model and BIM data of the proposed development.

Producing construction documentation from a 3D Model has a number of advantages, clash detection between disciplines can be detected early avoiding costly re-design late in the project. Documentation such as schedules, plans and even visualisations are automatically updated when changes to the design are made. This reduces wasted time and money by keeping documentation coordinated if changes are made late in the project which everyone tries to avoid but inevitably happens.

During project feasibility and obtaining planning permission, we seem to be having more lengthy discussions with the Environmental Agency these days with regards to flooding in conjunction with global warming and climate change. The Environmental Agency provides us with maps showing the 1 in 200 year Tidal Events + 2070 Climate Change Prediction Depth Grid Maps centred on our site. One assumes that they obtain levels from the OS Maps and or aerial photographs to build such models.

Alan Wooldridge Engineering & BIM Manager based at our London office established that it was possible to create BIM topographical models of the existing and proposed site layouts and graphically Illustrate the extent of the flooding using Civil Engineering Cut and Fill techniques within Revit to emulate the rising flood water.

BIM Technician Rikki Hartigan also based at our London office used an AutoCAD 2D site survey drawing as an underlay to create the 3D topographical model of the existing and proposed site layouts for a proposed development for a well known supermarket chain

The attached Images below show accurately the extent and pattern of the flooding of the site under the influence of a rising flood water level.

Existing Site PlanProposed Site Plan

Using the BIM Data and Revit, we were able to provide the Environmental Agency with drawings at set levels of flood water. We also provide them with the volumes of water held on the site for each 100mm increment of depth of the flood water for the existing and proposed site layouts.

An additional benefit was that the client and his insurers could see to what extent his proposed building was at risk from flooding, and the model helped set the proposed floor level of the stores such that it was not at risk of the 1 in 200 year Tidal Events + 2070 Climate Change Prediction Flood event.

If you want to find out more about Flooding, Flood Risk assessments or how we use BIM and Revit, then please contact us.

Structural Engineering Civil Engineering