Layered high-performance concrete plates interacting with granular soil under blast loads: an experimental investigation

Abstract

A new-layered precast tunnel segment made of different fibre-reinforced cementitious composites is here proposed. The article aims to study the effect of impulsive distributed pressure over tunnel rings under blast loads for the development of this new design solution. Shock tube experiments have been carried out to investigate a small portion of tunnel segment interacting with soil subjected to a plane shock wave. A set of accelerometers mounted on the specimen and placed inside the soil, as well as strain gauges mounted on the ad hoc chamber containing the specimen and the soil, have provided valuable information on the soil–structure interaction response. A careful investigation on the possible delamination between concrete layers is also carried out by UPV measurements. The experimental results have pointed out the great potential of this new design solution for precast tunnel segments subjected to internal explosions.

Keywords:

• internal tunnel explosion
• fibre-reinforced concrete (FRC)
• layered thick plates
• soil–structure interaction
• inter-layer delamination
• shock tube test

Acknowledgments

The research was financially supported by European INTERREG IT/CH 2006_2013 project ACCIDENT ID 7629770, measure 2.2. The authors want to thank Lorenzo Corti and Luca Corti for their help in the experimental campaign as a part of their M.Sc. thesis in Civil Engineering at Politecnico di Milano. A special acknowledgement goes to Andrea Stefanoni for his assistance in carrying out the experimental tests.