Modified Rammsonde tests in layered compacted snow
Modified Rammsonde tests in layered compacted snow
at : May 22, 2019 16:33:51  (view:295)

Modified Rammsonde tests in layered compacted snow

 

ZHUANG Feng1, LU Peng1, LI Zhijun1, HAN Hongwei2 & LI Wei1

 

1State Key Laboratory of Coastal and Offshore Engineering, Dalian University of Technology, Dalian 116024, China;

2School of Water Conservancy and Civil Engineering, Northeast Agricultural University, Harbin 150030, China

Received 14 February 2019; accepted 22 May 2019

Abstract

The investigation of snow’s physical and mechanical properties has long been a topic of interest to researchers for the demand of constructing compacted-snow runways in Antarctica. In an attempt to assess the strength of layered compacted seasonal snow, penetration tests using modified Rammsonde were conducted in Harbin, China in early 2018. Compared with the previous models, the modified Rammsonde is lighter overall, with improved resolution, thus more suitable for seasonal snow; the mechanical structure was adjusted, and the reading of depth data is more convenient. A total of 74 penetration tests were carried out and the results were analyzed both qualitatively and quantitatively. The results of these analyses demonstrated the applicability of the device, and revealed that several factors affect the estimate of the strength of layered compacted seasonal snow via the cone penetrometer. Such factors include confining pressure, penetration energy, as well as snow material properties, particularly the compaction of the snow undergoing penetration. A linear relationship between penetration pressure and density of snow was also established. The effect of age hardening on penetration pressure was studied and the microstructure of snow particles was observed through a microscope. These analyses showed that the cone penetrometer and data processing methodology applied in this study enable a rapid estimate of strength in seasonal snow to be provided, and may be considered for application in Antarctica after further modification. This would provide a scientific basis for the design of China’s Antarctic ice sheet airport.

Keywords

Layered compaction, penetration, resistance, snow hardness, snow age hardening

Citation

Zhuang F, Lu P, Li Z J, et al. Modified Rammsonde tests in layered compacted snow. Adv Polar Sci, 2019, 30(2): **-**, doi: 10.13679/j.advps.2019.0003