Harald Baardal adjusts one of the jacks on top of the framework before it is pulled forward
This viaduct will be the highest and, at 307 metres, the longest on the Sky – Langangen motorway being built as a working partnership between Veidekke and Albert Hæhre.
With fresh heart
“We have made smooth progress. Theory and practice are the same, but the concrete formulae are better and additives and formwork have been improved; for instance, we use steel formwork that comes away more easily“, explains Arne Havikbotn of V-Teknikk.
“So we set off with fresh heart on the first pair of columns for Kjose viaduct on 9 November 2009,” he adds. Sub-contractors Interform are operating the sliding formwork, with Br. Reme as sub-contractors for reinforcement. The columns are constructed in pairs with walkways in between.
“We were a little nervous to begin with. These are massive things we’re building: an oval cross section 5.5 by 2.5 metres and up to 56 metres in height, using 10.8 cubic metres of concrete per poured metre per column. The problems tend to come in the standards’ hardening limitations. We are using Anlegg FA cement, which develops heat quite slowly. The target was 3.2 metres a day. We didn’t manage it to begin with, but after adjusting the formula we managed just over three metres,” explains technical coordinator Knut Lauvålien, on loan from V-Teknikk.
“We are pouring eight loads at a time, 16 times a day. The first pair of columns was ready in 14 days. The quality has been as expected and there have been no complaints. The Norwegian Public Roads Administration’s Bridge Division had a whole delegation here,” explains Lauvålien.
Just as exciting every time
The first cast section of the superstructure of Kjose viaduct, from the pier to the first pair of columns of the southbound lanes, has just been completed, and the specially constructed framework is being pulled 66 metres forward to the next pair of columns. The two frameworks weigh 45 tonnes each and are pulled forward by the tower crane using a pulley system.
“Just as exciting and demanding every time,” says Arne Havikbotn, who is following the process. It will be moved forwards four times in all, before the entire concrete superstructure is finished sometime in August. Then work will begin on the side girders. The frameworks, like all the steel structures for this project, have been designed by Fredrik Smith, Veidekke’s project manager. Some of the concrete work is being handled by sub-contractors; Veidekke Telemark for example is building some culverts that cross below and environmental tunnels.
