Runway Shoulder Widening
Christchurch Airport, Christchurch New Zealand
The Runway 02-20 shoulder widening project, otherwise known as Project Takatū (translation: prepared for immediate action or use), created a safe and code compliant environment for the arrival of Code F aircraft to use at Christchurch Airport.
The contractor removed the existing concrete shoulders and replaced them with new structurally adequate 7.5 metre shoulders on either side of the entire 3,288-metre-long runway.
Each night shift lasted from 2100 to 0500 the next morning, the latest time the full length of the runway was required to become available for aircraft operations. Each shift would start with a pre-activity briefing, equipment line-up by 2030 and access to the runway work site at 2100. Removal of the existing concrete shoulders and immediate assessment of the subgrade were followed by placement of cement-treated subgrade generated from an on-site pugmill. The crucial task of protecting the tightly bound temporary surface, prior to the placement of the final 100mm layer of AC14, was achieved with the application of bituminous tack coat.
Meticulous planning and coordination were key to the success of the project. Each shift had to be broken down into precise stages and tracked very closely with go, no-go decisions from the construction engineers throughout the night. Airport personnel guided access to the site, implementing either a reduced length or displaced threshold runway configuration. The configuration was based current weather conditions. The construction engineers provided immediate decisions and guidance to facilitate the progress of work for without a cohesive team the chance of re-opening the runway on time was unlikely.
The project met several challenges, one of which was the introduction of a large international airline that wanted to start using the runway in December, about the mid-point of the project. The dilemma was that aircraft were not scheduled to depart until 2230 on any Sunday, Wednesday, and Friday. This caused challenges to an already short shift and start and completion times that could not be changed. An idea-generating session led our team to develop the proposal of double-shifting a paving crew in November just before the start of the modified work window. The additional crew was responsible for the critical path work of cement-treated-base. The two crews completed 25% of the total cement-treated-base in one month at minimal additional cost, thus saving time to the overall programme.
There are always ways to improve existing construction processes despite unanticipated challenges. Vogt CE understands the construction processes necessary to meet the unique demands of airport construction. We know how to generate ideas that speed construction processes and save time since a key to greater efficiency is to be imaginative and open to change.