Integrated approach for quality control of fibre-reinforced sprayed concrete for tunnel lining

Abstract

The quality control of fibre-reinforced sprayed concrete (FRSC) for tunnel linings has evolved significantly in recent years. One of the main innovations concerns the control of FRSC in the lining using small-scale tests of cores extracted from the tunnel instead of the traditional approach, based on the characterization of panels sprayed on moulds. This study combines experimental and numerical investigations to evaluate if constitutive models derived from small-scale tests, such as the double punch test (DPT) and double-edge wedge splitting (DEWS) test can be used to predict the behaviour of larger panels in the round panel test (RPT) ASTM C1550. Results confirm the link between the new and the traditional approaches. Findings demonstrate that small-scale tests can be considered as a viable method to evaluate the mechanical behaviour of FRSC both in regular quality control programs and for verifying an existing tunnel lining condition.