FAQs

As the first point of call, Ground Science will adopt the pavement design guidelines as detailed in the local council publications. Some Councils have adopted the use of the Growth Areas Authority (GAA) Engineering Design and Construciton Manual or more recently, the Metropolitan Planning Authority Guideline. Ground Science also refers to the guidelines presented by Austroads and VicRoads where applicable.

Yes we can. Ground Science have assisted various Client's with the preparation of a sewer backfill procedure in accordance with the MRWA guideline. Speak to a geotechincal engineer at Ground Science who will be able to assist with the process and required information.

Where controlled clay fill in excess of 0.4m (0.8m for sands) has been placed on a site, the site classification must be re-assessed due to the potential movement of the fill and underlying natural soil from the time of placement to the equilibrium moisture condition. Where controlled fill has been in place for less than 5 years, Section C2.3.2 of AS2870 (2011) details that seasonal shrinkage and swelling cracks that naturally develop are not present.  Given the absence of these cracks, the characteristic surface movement (ys) of the site increases and in most cases, a higher site classification may apply. 

The CSIRO publication, "Foundation Maintenance and Footing Performance: A Homeowners Guide" (2011) will provide the necessary information. A copy can be obtained from the following link: http://www.publish.csiro.au/pid/7076.html

As per the new AS2870 (2011) Residential Slabs and Footings code, a shrink/swell index must be performed with each site classification to enable a better understanding of the soil reactivity, especially in areas of Victoria with known highly reactive soils such as the north & west. This test has proved its importance with some sites in the east recording high shrink/swell index values, where low reactive soils are typically expected - these sites, which would typically be a Class M using the older method of classifying a site were now classified as Class H1 or Class H2. The test enables the calculation of a ys value (characteristic surface movement) to assign a site classifcation to the site. For example, a ys value of between 20mm and 40mm is a Class M and a ys value of between 40mm and 60mm is a Class H1.

A 'Soil Test' is also known as a 'Site Classification' and involves an assessment of the soils on your site in relation to the proposed development. In general, the footing design of your property will depend on the reactivity and condition of the soils which will form the foundations for your house. A site classification is performed by the drilling of boreholes and onsite logging of the soils to understand the various soil types. This information is then extrapolated with site characteristics such as geology, climatic zones and associated soil categories to assign a site classification (Class M, Class H1, Class P for example) to assist the structural design. The works are conducted in general accordance with AS2870 (2011) 'Residential Slabs and Footings'. This standard has been recently updated and has made the performance of shrink/swell index tests relatively important as an added assessment factor of the soils on the site.