Date of Graduation

2017

Document Type

Thesis

Degree Type

MS

College

Statler College of Engineering and Mineral Resources

Department

Mining Engineering

Committee Chair

Brijes Mishra

Committee Co-Chair

Thomas Evans

Committee Member

Aaron Noble

Abstract

The use of anchorage in satellite and spacecraft design has been largely restricted to harpoon-inspired technology based on anticipated low strengths of cometary and asteroid material. Initial results from the Rosetta mission to comet 67P/Churyumov- Gerasimenko, however, have demonstrated both larger-than-expected compressive strengths of cometary materials and the importance of adequate anchorage to mitigate the risk of mission failure. The field of rock mechanics can provide unique insight into the design of these satellite and lander anchors by drawing on existing roof bolt technology. This study compared the behavior of tensioned point anchor and untensioned fully-grouted roof bolts with a polyurethane-anchored bolt under environmental conditions similar to those anticipated in space. These conditions include variation in possible material types as well as variations in regolith properties, anchorage length, and low operating temperatures.;Using a Box-Behnken experimental design, this study first compared the effects of anchor depth and rock strength on each of the three anchorage types in a competent rock strength regime. The study then examined the effects of compaction, water content, and temperature on each anchor type in a regolith environment. The subsequent data analysis identified one anchor type as the overall best anchor for these environments. This finding has led to a preliminary design recommendation to advise space agencies on satellite anchor construction based on the target orbital body's anticipated environmental and "exogeologic" conditions.

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