Rejuvenating NZ's rail bridge asset

Since 2004 KiwiRail has significantly increased the rate of bridge renewals and refurbishments throughout the New Zealand rail network. This has primarily been driven by an aging asset and that there had been relatively low levels of investment towards NZ rail infrastructure in the two decades leading up to 2004. Engineers have been faced with the dual challenge of significantly increasing productivity while making the best use of the limited funds and resources available. This has led to a number of innovative initiatives through standardizing designs, fast/reliable construction techniques and efurbishment/strengthening of existing structures. The majority of the NZ Rail Network was constructed in the first half of the 20th Century. Most of the 1535 rail bridges in the network are still the original structures from when railways were first built and were constructed using common materials and designs of that time (timber, mass concrete, cast iron and steel). In particular, as at 2004, over 50% of the bridges in the network were either entirely or partially constructed out of hardwood timber. Large numbers of these timber bridges were reaching the end of their serviceable lives. Special programmes were initiated to replace timber super and substructures. Some of the standard designs developed consist of slim line steel spans, driven H piles, reinforced concrete bored piles which incorporate a driven plug, ballast deck concrete box culverts. All the designs have been developed with the need to undertake construction in a live rail corridor where there are limited opportunities for a full rail shut down to execute bridge change-overs and be very cost effective. The current rate of productivity is about one bridge treatment being completed per week. This paper describes the general design constraints and solutions that have been used and construction techniques plus provide the unit-rate costs of construction for each solution. It discusses the background factors that are the drivers for the strategic asset management plan for the NZ rail bridges.

Media Info

  • Pagination: 10p.
  • Monograph Title: Rejuvenation and renaissance: CORE 2010: conference on railway engineering, 12-15 September 2010, Wellington, New Zealand

Subject/Index Terms

Filing Info

  • Accession Number: 01517089
  • Record Type: Publication
  • Source Agency: ARRB
  • Files: ATRI
  • Created Date: Mar 4 2014 8:07PM