Night Works at a Busy Auckland Bridge

Project Requirements

Because of the need to keep Auckland City traffic flowing during the day, CSI sometimes needs to work overnight on upgrades and maintenance of the city’s infrastructure.

So it was with this busy Auckland bridge in the city.

CSI needed to work after hours and perform controlled breakouts at specified locations to reveal the extent of corrosion in existing reinforcement.   Scanners were used to identify the location of the steel for these breakouts.

In situ carbonation testing was to be carried out in the proximity of each breakout location to establish the degree of carbonation within the concrete; which in turn, can be an indication of potential corrosion of reinforcing bars.

CSI was also asked to conduct chloride contamination tests.  Chloride can potentially attack the passive layer of reinforcement if Oxygen and Water are present.

CSI followed up these tests by taking core samples to check concrete composition back at the lab.

Due to the location, there were some challenges to ensure the work was completed to the highest environmental standards and controlled all slurry, dust and other waste material.  CSI also had to prevent anything falling on the motorway below and repair breakouts to the highest possible standard.

Night Works at a Busy Auckland Bridge
Night Works at a Busy Auckland Bridge
Night Works at a Busy Auckland Bridge

Solutions

Working in the dark does have its challenges and this was overcome by using very high powered Halogen Lighting running off a generator.  Those lights were very Illuminating!!

To help control the waste material CSI used plywood back boards to prevent any debris falling on the motorway below the bridge.

The excellent procedures CSI have for managing slurry and dust when performing breakouts were put to good use which involved employing the use of vacuums and ‘socks’ to collect liquid slurry and dry waste.

If you refer to the CSI services page you will see the procedures for Corrosion Surveys. CSI was able to successfully get results from the Carbonation and Chloride testing, and establish the Concrete Composition from the cores that were taken on site.

CSI used Sika Monotop and Structural Repair Mortar to repair breakouts to the highest standard.


Benefits of Solutions

CSI was able to achieve minimal impact on the environment and Auckland traffic through their management of their aspect of the project.   By working at night time the disruption to Auckland traffic was successfully kept to a minimum

Since CSI was able to get reliable results for the client, they could then determine what maintenance was required on this piece of Auckland Infrastructure.

CSI was also able to repair the testing areas and leave the site in the best possible condition for ongoing use.