It is very important to follow the correct procedure when preparing building sites ready for either construction of Industrial or Commercial buildings.
Generally, a new or existing site will have some form of vegetation on it, whether it be trees or grass or both. It’s important to remove all of the vegetation when stripping a site. If you just fill or build over the top, organic material will rot and decay over time and the ground will settle causing movement and the possibility of the concrete pavement cracking. It is also equally important to remove the topsoil that the vegetation is growing in (say 100-150mm deep) as this also contains organic materials such as roots.
Once the site is properly stripped then the process of laying the correct building foundation can begin.
If the site needs filling to bring it to the correct height or level, then this must be done under supervision of a Geotechnical Engineer to ensure the correct compaction is reached (this is called ‘Level One’ supervision).
Once the site has been checked for ‘soft spots’ the select fill must be brought in, spread with a dozer and rolled with the use of a vibrating ‘pad foot’ roller in layers of around 200mm thick. It is also very important to add the correct amount of water to help the material to key in and bind together. The moisture content will be decided by the Geotechnical Engineer on site, depending on the type of fill being imported. During the filling process, the Geotechnical Engineer does testing of each layer to make sure that a minimum of 98% compaction is achieved.
It is critical that this procedure is followed otherwise the Structural Design Engineer may have to design much larger and more expensive building foundations, as the fill may be classed as ‘uncontrolled’ and could be subject to settlement.
Here at Clarke’s Design & Construct we achieve 98% minimum (sometimes it’s as high as 104%) compaction under Level One supervision for all our projects where filling is required.
For more information and handy hints in this and other building procedures, please call 1300 11 25 11.