Allan Block® Retaining Wall System – Brentwood Estate
Brentwood Estate was a new subdivision with high quality amenities and features, including incredible views to one of New Zealand’s national treasures, lake Taupo.
Initially Taupo ITM offered the client the option of using either timber or Allan Block as retaining wall’s structures. Previous experience a few years earlier with the Allan Block RW system in a smaller and earlier part of the subdivision, and the fact that it was going to add more value to the sections and provide not only a longer life expectancy, but a guarantee seismic performance, made the client select the Allan Block RW system as the right option.
Design
After the type of block and colour were signed off, the Bowers technical design carried out a series of preliminary designs, offering different backfill and reinforcement options for each of the 15 retaining walls initially considered. The project time frame was tight as we got the call just before Christmas, so both the technical and manufacturing teams put extra hours to make sure the project was not delayed and get it moving forward. Technical support was provided to the project design engineers, regarding No-fines concrete specs, geogrid placement on outside curves, and so on.
Installation
The client asked the Bowers sales team to put forward a short list of experienced contractors that could complete the project satisfactorily. Alicon Limited, with more than 10 years doing some of the most amazing Allan Block retaining walls around the country was selected to perform the task.
Installation was smooth and carried for a couple of months. Bowers provided sales and technical support along the way when needed to anybody involved in the project design and installation. One of the peculiarities of the Brentwood Estate project was the used of local and readily available Pumice soils as backfill material in the reinforced zone interacting with the geogrid.
The value of using a very skilled and passionate contractor such as John Graham and his team, was the fact that his knowledge and understanding of the system, made him provide improvements and suggestions to the client regarding changing sharp corners for curved walls, this way avoiding weak points on the structure and enhancing the stability and beauty of the Allan Block retaining walls.
