Comparison of field and numerical modelling data for the steel pipe umbrella arch applications

摘要

Umbrella arch application is generally applied by using 4 inches Φ steel pipes. This application requires special experience and special machine for drilling holes to embed the 4 inches Φ steel pipes. In such a case, a machine to make umbrella arches in tunnel face, a machine to embed bolts at umbrella arch overthrust and also a machine to make excavation are required. As an alternative to this application, both excavation and umbrella arch application can be made with just one machine when 2 inches Φ steel pipe umbrella arch application is sufficient. Hereby, both a positive effect made on project costs by increasing machine usage rate and less amount steel pipes are used.