DOI: 10.5194/tc-8-1407-2014
Scopus记录号: 2-s2.0-84905453397
论文题名: The influence of edge effects on crack propagation in snow stability tests
作者: Bair E ; H ; , Simenhois R ; , Van Herwijnen A ; , Birkeland K
刊名: Cryosphere
ISSN: 19940416
出版年: 2014
卷: 8, 期: 4 起始页码: 1407
结束页码: 1418
语种: 英语
英文摘要: The Extended Column Test (ECT) and the Propagation Saw Test (PST) are two commonly used tests to assess the likelihood of crack propagation in a snowpack. Guidelines suggest beams with lengths of around 1 m, yet little is known about how test length affects propagation. Thus, we performed 163 ECTs and PSTs 1.0-10.0 m long. On days with full crack propagation in 1.0-1.5 m tests, we then made videos of tests 2.0-10.0 m long. We inserted markers for particle tracking to measure collapse amplitude, propagation speed, and wavelength. We also used a finite element (FE) model to simulate the strain energy release rate at fixed crack lengths. We find that (1) the proportion of tests with full propagation decreased with test length; (2) collapse was greater at the ends of the beams than in the centers; (3) collapse amplitude was independent of beam length and did not reach a constant value; (4) collapse wavelengths in the longer tests were around 3 m, two times greater than what is predicted by the anticrack model. We also confirmed the prediction that centered PSTs had double the critical length of edge PSTs. Based on our results, we conclude that cracks propagated more frequently in the shorter tests because of increased stress concentration from the far edge. The FE model suggests this edge effect occurs for PSTs of up to 2 m long or a crack to beam length ratio ĝ‰¥ 0.20. Our results suggest that ECT and PST length guidelines may need to be revisited.© Author(s) 2014. CC Attribution 3.0 License. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/74810
Appears in Collections: 影响、适应和脆弱性 气候变化与战略
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作者单位: US Army Corps of Engineers Cold Regions Research, Engineering Laboratory, Hanover, NH, United States; Earth Research Institute, University of California, Santa Barbara, CA, United States; Southeast Alaska Avalanche Center, Juneau, AK, United States; WSL Institute for Snow and Avalanche Research SLF, Davos, Switzerland; USDA Forest Service National Avalanche Center, Bozeman, MT, United States
Recommended Citation:
Bair E,H,, Simenhois R,et al. The influence of edge effects on crack propagation in snow stability tests[J]. Cryosphere,2014-01-01,8(4)