Item: Preliminary investigations of glide/creep motion sensors in alta, utah
Title: Preliminary investigations of glide/creep motion sensors in alta, utah
Proceedings: Proceedings of the 1996 International Snow Science Workshop, Banff, Canada
Authors: Bob Rice, Dan Howlett, Rand Decker, Department of Civil Engineering, 3220 MEB University of Utah,Salt Lake City, Utah 84112, Snow Safety, Alta Ski Lift Co. And Chairman, Center for Snow Science at Alta, P.O. Box 8007, Alta, Utah 84092
Abstract: Creep and glide in an alpine snowpack can lead to snowpack failure including snow avalanching. With a snoid rate of change in creep or glide with respect to time without an increase in snow strength, avalanches may be expected. Deformation in the snowpackby creep and glide are necessary measurements in determining stress in snow slabs. In order to detect in real time the creep and glide in an alpine snowpack, the use of creep/glide sensors are utilized. These sensors are capable of detecting deformation rates and avalanche events. The sensors are connected by hardwire to a multiplexer and a datalogger where real time data are collected on creep and glide motion. This motion deflects the sensors which are fixed within a one meter poly vinyl chloride pipe which is attached to a coaxial spring. The deflections are monitored on two axis. Voltages corresponding to angle of tilts are recorded. These voltages are produced by a solid state accelerometer. Preliminary testing during the winter of 1995-1996 was carried out on Mt. Baldy in Alta, Utah. Valuable lessons were learned during the winter that will be implemented next winter. A number of significant events were captured by the sensors. These events included both the elastic response of the snowpack when explosives resulted in widespread avalanching and the-rapid increase in creep rates which preceded avalanching. The cause and effect between successful avalanche control with explosives and corresponding high creep rate events warrant further field investigation. The goal of the project is to improve or optimize avalanche forecasting and control using creep/ glide motion sensors.
Keywords: creep, glide, slab avalanche, forecasting
Digital Abstract Not Available