Use of recycled aggregates in fibre reinforced shotcrete: mechanical properties, permeability and frost durability

摘要

As part of a construction project in Oslo, Norway, wet-mixed steel fibre reinforced shotcrete was used substituting up to 20% of the aggregate with recycled aggregate. The shotcrete was used outdoors for the main purpose of protecting a lightweight bridge foundation. This paper presents some of the results from laboratory testing of shotcrete specimens made with recycled aggregates. The investigation was performed as a part of RESIBA, an ongoing research project in Norway demonstrating the use of recycled aggregates in various applications. The results indicate a reduction of approximately 15-20% relative to the control mix for compressive and flexural strength of shotcrete with up to 20% recycled aggregate. The use of recycled aggregate however does not appear to have any effect on the residual flexural strength or the flexural toughness. Furthermore, results from durability testing (freeze/thaw-test, water intrusion, and capillary absorption) do not show any clear reduction in durability for shotcrete produced with up to 20 % recycled aggregate.