Overview
The City Rail Link (CRL) project was given the Infrastructure Sustainability Council (ISCA) measured carbon reduction goals to meet and exceed for stage one of the project which included the building of the two tunnels near the existing Post Office building - a heritage site.
To help achieve the ISCA rating goals recycled crushed concrete was used from Green Vision for two parts of the project build.
Recycled crushed concrete aggregate (GVRCC10) was used as a replacement for quarried aggregates in a flowable fill concrete supplied by Allied Concrete. The use of Green Vision recycled crushed concrete resulted in carbon saving of around 55% (using ISCA model calculations). Please refer to the table 1 below showing the saving when using the Recycled Crushed Concrete as base course material versus using a quarried finite aggregate.
Solution
Green Vision partnered with Allied Concrete Ltd to supply a 10 Mpa strength concrete that would be suitable to use as flowable fill in a non-structural concrete application.
Outcome
+ Greatly reduced carbon footprint
The product was easily manufactured, helped with regular just in time deliveries of RCC10 material made to the Allied Concrete plant in Leon Leicester Place, Mount Wellington which is located 4.7 km from the Green Vision Recycling plant reducing the carbon footprint of the concrete by 40%.
+ Specification met
The concrete was manufactured without any detrimental production issues and was functional in the application as a low carbon flowable fill option.
+ Contributed to helping meet the project ISCA goal
Table 1
Added Value
+ Cost of the product was similar to finite resource aggregate
+ Contributed to help meet CRL1 projects ISCA carbon goals
+ Provided flexible supply solutions
