Experimental Setup (IMAGE) Nagoya University Caption Tunnel compression experiment using a universal testing machine was performed in this study (A). A wet granular layer with horizontal tunnel structure was prepared in an acrylic vessel (B). The entire wet granular layer including the tunnel structure was uniformly compressed. Credit Ayuko Shinoda and Hiroaki Katsuragi Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.