For one of the major real estate projects in Chennai, out of 100 bored piles of 500mm and 750mm for each building few piles showed some distress. Tests conducted by two testing agencies provided conflicting results and the clients were not sure whether to accept or reject the piles. Finally, Geo Dynamics was called to do testing based on their expertise and our team correctly evaluated defects in many piles. These were also exposed for confirmation. Based on the findings, most of the piles for few buildings were rejected and the entire piling was properly redone. Tests conducted on new piles had no problems and the capacity confirmed by high strain and static test results. Low Strain testing proved to be a boon as otherwise it would have lead to dangerous consequences for the developer. Geo Dynamics also proved their expertise in this form of testing. It also proved that integrity testing is a state of art technology and merely trying to conduct 100’s of test at lower price may not be a good choice.
Routine PIT testing on 10 piles for a project in Goa showed defect in 3 piles. Eventually all the 150 piles were tested at the project and the results showed defects in atleast 40 of them. Many results were confirmed by manual excavation. The site was critical chemical plant and helped the client in avoiding major future accident that could have been caused due to pile foundation failures.
For a major pharmaceutical plant in Gujarat, bored piles of more than 400 piles of 900mm were installed. Geo Dynamics was engaged directly by the client to do testing and 40 piles showed defects in the upper shaft around 4m-7m and many others showed short lengths. The local contractor engaged another agency who confirmed almost all the piles as good. Eventually some piles were exposed for depth from 4m to 7m and all of them showed clear defects proving the integrity and capability of Geo Dynamics team.
Integrity Tests have also been routinely used to evaluate possible defects like cold joints, soil inclusions, or to evaluate integrity in case of specific concreting problems on site. It is very important that the agency engaged to do low strain testing understand the types of piles, their behaviour, possible problems that can occur, local conditions before an interpretation is done. It is (ultmost) important that the testing engineer is honest and non under any undue influence as sometimes more than the cost of testing, the entire project may stand risk. It is a risk to the builder or owner, consultant and contractor if major defects are not reported and any disaster may lead to serious consequences for everybody concerned.