| || Quantitative Step-loading Block Test: A Substitute for Loaded-column Test
Author : Gusain, H. S.;Chandel, Chaman;Ashwani;Prashar, Ankur
Source : Defence Science Journal ; Vol:56(4) ; 2006 ; pp 577-583
Subject : 551 Geology
Keywords : Stability test;Failure load;Failure plane;Great Himalayan range;Snowpack stability test;Quatitative step-loading block test;QSLTB;Unstable snow;Shear frame test;Loaded-column test
Abstract : A new snowpack stability test, quantitative step-loading block test (QSLBT) has been developed and used operationally by the Snow and Avalanche Study Establishment during the winter 2004-05 at Patsio Research Station in Great Himalayan range. This test is simple, takes less time in measurement, and effectively communicates the results. In this test, an isolated snow column of area 13 cm x 18 cm (0.234 m2 or may be up to 0.30 m2) is cut out of the wall of a snow pit. A wooden block of known weight (0.21 kg) and of the dimension 13 cm x 18 cm is placed over the snow block and loaded in steps with iron weights of known quantity. On loading if the block fails, the height of failure from ground and the load by which the failure of block has taken place, are noted. While most of the stability tests in snow provide just an estimate of snowpack instability, this test provides the quantity of load required to fail the snowpack. More than 40 tests were carried out in Great Himalayan range during the winter 2004-05 and were compared with the shear strength of the failure plane. The results are in good agreement with shear frame test.