Causes of failure and lessons learned

It is a sobering thought that foundation failures continue to occur in spite of rapid technological advances. In many instances this is because although state-of-the-art technology is available, to an individual practitioner it may not. In some other instances, the technology is available but pressure of time, budget and commercial considerations may prevent the complete utilization of current 

A foundation may fail due to lack of technology, i.e. the state of the technology which is available is not adequate to cope with the problem at hand. Although this seems to be rarely the case, the situation does arise, and if it is due to ground difficulty, it is sometimes feasible to relocate the structure concerned to avoid the difficulty. If not, the client should be informed of the inherent risks which are being faced. 

Some foundation failures are caused by inadequate site investigation. On rare occasions failures have been caused by the complete absence of site investigation. Both are due to ignoranee, laek of expertise in site investigation or pressure from the client to save cost. It has been said that you pay for a site investigation whether you have one or nof (Littlejohn 1991). This is beeause an inadequate site investigation can lead to either over-conservative design, which is wasteM and expensive, or to foundation difficulty or even failure. 

This is the second major cause of foundation failures (Chan 1996). Common construction shortcomings in foundation include  

Static load testing remains the most reliable technique for assessing single pile performance. Such testing should be started early in the construction program to verify that both the design and construction are satisfactory. 

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