June 18-21, 2006
Natural hazards, like avalanches and rock falls, will always be a major concern for infrastructure, i.e. roads and railways, in mountain areas. Several measures are available to protect this infrastructure, but especially in areas with steep slopes, rockfall- or avalanche galleries are commonly used. These structures, which are made to withstand high impact forces, can be made of reinforced/pre-stressed concrete culverts covered with soil. A possibly cheaper and equally safe alternative could be to use a buried corrugated steel culvert.
To investigate the use of buried corrugated steel culverts as rock fall protection structures an experimental study has been carried out. A 4.0 m span half arch corrugated steel culvert was buried in soil and instrumented during rockfall loading. Rock blocks with various weights have been dropped from different heights on a corrugated steel culvert covered with a cushion material. Tests were conducted with dense backfill in near zone and regular backfill in the cushion layer zone.
Measurements were made during both construction phase and during rockfall phase. During construction phase measurements were made to monitor culvert shape and culvert strains. During impact loading from rock blocks decelerations and transmitted accelerations were monitored together with change of culvert shape and deformations. Deceleration of the rock blocks was also documented with a high speed camera.
The goal of this study were to obtain knowledge which can be used in design codes in the future for flexible rockfall- and avalanche shelters.
R. Ebeltoft, J. O. Larsen, and S. Nordal, "Instrumentation of Flexible Buried Culvert Subjected to Rockfall Loading" in "Geohazards", Professor Farrokh Nadim, International Centre for Geohazards, Oslo, Norway; Dr. Rudolf Pöttler, Managing Director, ILF - Consulting Engineers, Innsbruck, Austria; Professor Herbert Einstein, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA; Professor Herbert Klapperich, TU Bergakademie Freiberg, Institut für Geotechnik, Freiberg, Germany; Professor Steven Kramer, University of Washington, Seattle, Washington, USA Eds, ECI Symposium Series, (2006). http://dc.engconfintl.org/geohazards/8