Nest excavation in social insects is an integral part of a colony’s life cycle. Soil-dwelling colonies build complex systems of narrow underground chambers and tunnels spanning thousands of insect body lengths below the ground. The nest excavation is performed by multiple animals simultaneously and is governed by local interactions of the workers with environment and other workers. The challeng...

This paper presents a methodology for evaluating life safety risks in road tunnel fires. The methodology considers three realistic fire scenarios, smoke spread, occupant evacuation, and reliability of fire suppression systems. The three fire scenarios represent three variations of fire growth rates. The road tunnel in this study is assumed to have two traffic tubes, a longitudinal ventilation s...

The SHPB experimental device was adopted to carry out the uniaxial impact tests in studying failure characteristics of combination surrounding rocks and primary support for tunnel, so as explore key factors affecting its dynamic strength deforming properties. To simplify practice model tunnel construction, specimens combined by rock were simulated concentric annular sandstone cement mortar this...

On the basis of analyzing engineering geological conditions inlet slope diversion tunnel on left bank a hydropower station in Jinsha River, overall three-dimensional generalized model is established according to and topographic data during construction period. According excavation support scheme, displacement, stress, strength reserve safety factor after all are calculated simulated under exist...

The main objective of this study was to investigate the performance of a roadheader used for the excavation of Küçüksu Sewage Tunnel having a length of 1037.52 m. The tunnel is located in Anatolian part of Istanbul and constructed by STFA for Istanbul Water and Sewerage Administration (ISKI). Detailed statistical analysis showed that net advance rate of the roadheader is directly influenced by ...