For years geotechnical practitioners have commented on the failure of clients to appreciate the value of good site investigation and the benefits of obtaining more detailed information. Some of the benefits of a good ground investigation coupled with appropriate experience, analysis and design in foundation engineering projects are potential savings in construction costs, potential for assessment of foundation alternatives and reduction of risk in ground works. The savings can be significant – of the order of hundreds of thousands if not millions of dollars for the larger projects. Why then do clients seek to “save” money with taking on the lowest price ground investigation?
Littlejohn et al (1994) wrote:
Now and in the future, it is vital that financial decision-makers appreciate that you pay for a site investigation whether you have one or not, and you are likely to pay considerably more if you do not, or if it is inadequately designed, executed or interpreted.
Nothing much seems to have changed since those words were written, for in 2006, Egan reported:
For nearly a third of all the piling and specialist geotechnical contracts surveyed, the site investigation information provided was poor, preventing optimisation of the foundation solution. The cost to clients arising out of poor site investigation far exceeds the savings that could be made by following good practice when investing in a site investigation.
This presentation provides a guide to the various levels of ground investigation, analysis and design which are available and through the use of case histories, illustrates the significant benefits that higher levels of sophistication can bring to the project.
Engineers Australia members participating in AGS technical sessions can record attendance on their personal CPD logs. Members should refer to Engineers Australia CPD policy for details on CPD types, requirements and auditing guidelines.