In recent years in New Zealand there have been a number of tunnelling and deep directionally drilledrnpipelines projects that have required access shafts. Often these shafts are in urban environmentsrnwhere vibration and high noise levels are not tolerable. There are a number of methodologies thatrncan be adopted dependent upon the shaft plan area, depth and geology.rnThis paper will describe some different methodologies that can be adopted that use piling methodsrnsuch as large diameter piles, and secant piles. The paper will use case studies to highlight:rn? construction methodology,rn? specifi c methodology issues and constraints,rn? lessons learnt, andrn? recommended specifi cations.rnThe development of piling technologies in New Zealand has enabled the development of costrneffective solutions for the construction of deep shafts in sensitive urban environments.
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