Abstract

AbstractSnow appears as a granular material in most engineering applications. We examined the role of grain shape and cohesion in angle of repose experiments, which are a common means for the characterization of granular materials. The role of shape was examined by investigating diverse snow types with discernable shape and spherical ice beads. Two geometrical shape parameters were calculated from X-ray micro-computed-tomography images after a particle segmentation was performed with a watershed algorithm. Cohesion was examined by conducting experiments at six different temperatures between −40 and −2°C, assuming sintering as its cause, which accelerates with increasing temperature. As a cohesionless reference, experiments with glass beads were performed. We found that both shape and cohesion exerted about equally strong influence on the angle of repose. We utilized our results for an empirical model that describes the influence of shape and cohesion as additive corrections of the angle of repose of cohesionless spheres and explains all experiments with a correlation coefficient r2 = 0.95. With temperature and the chosen shape parameter as fitting variables, previous experiments with another snow type could be consistently included. The experiments highlight the relevance of these parameters in granular snow mechanics and can be used for model calibration.

Highlights

  • The angle of repose is a classical measure for the investigation of granular materials (Al-Hashemi and Al-Amoudi, 2018)

  • We investigated two of the most common snow types, rounded grains (RG) and faceted grains (FC), and ice beads (IB) as spherical model snow

  • Two typical natural snow types were investigated with rounded grains (RG) and faceted grains (FC), as well as spherical ice beads (IB) as model snow

Read more

Summary

Introduction

The angle of repose is a classical measure for the investigation of granular materials (Al-Hashemi and Al-Amoudi, 2018). As a characteristic of a granular material, it depends on particle and material properties such as size distribution and shapes of the granules, interparticle friction, surface roughness and cohesion. These properties are examined in the angle of repose by means of experiments (Shmulik and Robinson, 2002; Rackl and others, 2017), analytically (Albert and others, 1997) or numerically (Zhou and others, 2001), for model parameter calibration, or to examine their influence on the flowability of a material in general. It is recommended to clearly predefine the purpose of the angle of repose investigation and select the method (Al-Hashemi and Al-Amoudi, 2018), since it remains an important and interesting characteristic of granular materials

Methods
Results
Discussion
Conclusion
Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.