In recent years in New Zealand there have been a number of tunnelling and deep directionally drilled pipelines projects that have required access shafts. Often these shafts are in urban environments where vibration and high noise levels are not tolerable. There are a number of methodologies that can be adopted dependent upon the shaft plan area, depth and geology. This paper will describe some different methodologies that can be adopted that use piling methods such as large diameter piles, and secant piles. The paper will use case studies to highlight: construction methodology, specific methodology issues and constraints, lessons learnt, and recommended specifications. The development of piling technologies in New Zealand has enabled the development of cost effective solutions for the construction of deep shafts in sensitive urban environments.
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