"The most significant change this author/mud man extraordinaire has seen in the last 15 years of experience in the horizontal directional drilling (HDD) industry is not in the equipment or technology, but in the capabilities and accomplishments of drilling contractors, especially in the mini to mid-sized HDD drilling market."
Even the most conscientious and careful drilled shaft installation program can be subject to incidents during construction. Bad weather, unexpected delays in concrete delivery, equipment breakdowns or unanticipated ground conditions can produce imperfections or defects in the completed drilled shaft foundation.
This review is intended as a fundamental guide to various aspects of the technology, including drilling methodologies, flushing, drill hole deviation, monitoring and specifications.