Building Information Modelling
BIM is the progression from CAD, through to 3D modelling (great for visualisations but limited regarding information) to 3D models with information attached to the objects within it.
There are two main services in relation to 3D modelling that the arboricultural consultant can offer to the design team and it’s important to choose the right software.
The advantages for incorporating existing trees into the BIM landscape are as follows;
Allows the detection of clashes with proposed designs and services early in the design process
Sun and shade analysis
As the design changes the impact and constraints on existing trees is clearly visible.
Root protection areas and depths are visible in the BIM landscape for the design team.
Existing trees can be seen in relation to proposed landscape enhancements.
For arboriculture to reap the benefits above it is essential to accurately model existing trees to be able to demonstrate the advantages and constraints they pose to the scheme.
3D models of trees for visualisation, shading and other illustrative purposes can be easily created using software such as 3D CAD, SketchUp or similar. These trees can look very photo realistic but stock trees in these software packages are limited in their ability accurately represent a trees true measurements.
In relation to representing trees in line with BS5837:2012 in a BIM landscape we need to sacrifice the aesthetic detail and concentrate on the technical accuracy of the model. It will not be possible to ensure detection of clashes with a design scheme without this degree of technical accuracy. For instance, if root protection areas, crown heights and spreads are not modelled with accurate measurements how can we demonstrate the impacts that a design will have on trees or the benefits that they may bring?
There currently remains a software gap in regard to BIM for Arboriculture. This is mainly down to the fact that they are smaller disciplines than say, Landscape Architecture or Civil Engineering but there are also huge difficulties in dealing with organic form and representing it accurately in a computer programme without having to model each tree individually.