Waimarino rural bridges in need of work

Ruapehu Bulletin, Volume 12, Issue 565, 6 December 1994, Page 4

Waimarino rural bridges in need of work

Members of the Waimarino Community Board met in Ohakune last Thursday to consider a report from Ruapehu District Council's engineering consultancy manager, Jim Moore, detailing various defects on several rural road bridges in the Waimarino. Most of the report findings related to defective decking though one of the bridges - over the M akotuku Ri ver on the Ohakune/Raetihi Road at Raetihi - has suffered extensi ve j 'spalling' (splitting, chipping, splintering) of concrete on either side of the bridge. With the anticipated increased usage of this bridge . when Winstones start logging the Waimarino Forest it is expected that a bridge replacement, rather than a bridge i widening, will be required and a recommendation to this effect is to be included in the 1995/96 Land Transport Programme. If approved all costs would receive a 100 per cent subsidy from Transit New Zealand. The three bridges with defective decking are: Burnand' s Bridge on the Ruatiti Road; the Ruapehu Road Rail overbridge and; the Hoihenga Bridge on Hoihenga Road. The estimated cost of replacing the defective timber decking of the Burnand' s Bridge with pre-cast, pre-struc-ture concrete panels and adjusting the beams is $30,000. Ohakune' s Ruapehu Road overbridge above the railway line has a defective holding-down system which needs to be up-graded so as to improve the fixing of the concrete panel decking in place. There is a problem due to the presence of rail electrification cables under the bridge but most of the work can be carried out without needing Railways clearance or having the electricity tumed off. The existing decking on the Hoihenga Bridge is defective and needs replacing, estimated cost $30,000-$40,000. However, the existing structure of the bridge seriously restricts its loading capacity and the engineer's report recommends that the hangers (which connect the deck structure to the bridge cables) be strengthened to allow for a 10-tonne gross/5-tonne axle limit. Board member Winstone Oliver said eVen this recommended increase is inadequate to cope with fully-laden modem trucks and suggested an increase of a further five tonne gross to a maximum of 15-tonne. This might be achieved without exceeding the $40,000 budget.