Doctoral Dissertations

Keywords and Phrases

Cable shovel digging dynamics; Blasting decision criteria

Abstract

"Cable shovel excavation m the Athabasca oil sands is vital given the in-situ excavation of formation. Random occurrence of boulders in the oil sands formation results in varying mechanical energy input and stress loading of the shovel handle-dippertooth assembly. These problems pose significant failure threat to the shovel handledipper- teeth assembly resulting in unplanned downtimes, inefficiency and high production costs. A potential solution is the deployment of an intelligent shovel navigation technology. Currently, there are no prediction models, based on sound theory, for shovel navigation in this formation. This research is a pioneering effort toward developing dynamic models to accurately predict the formation resistances, optimal digging schemes and critical formation resistances on the dipper-teeth assembly.

Dynamic models of shovel digging, dipper material weight and the cutting resistance have been developed using the simultaneous constraint method, geometric simulation and the passive earth theory. These models have been combined into a cable shovel simulator. Factorial experimentation shows that the shovel performance is most sensitive to oil sand bulk density. A stochastic optimization scheme has been developed to optimize the oil sands digging. Experiments with the 21 00BL and 41 00TS shovels show that digging optimization is independent of shovel size. Over the defined domain, the optimal digging strategy is defined by crowd arm and hoist rope speeds of 0.25 ms·' and 0.7 ms·', respectively. The results show that the optimized digging conditions could reduce the digging time and energy per cycle by over 45% resulting in over 14% increase in annual production and over 35% decrease in energy costs. This is a pioneering study in oil sands excavation modeling providing insight into shovel excavation optimization"--Abstract, p. iii

Advisor(s)

Frimpong, Samuel

Committee Member(s)

Grayson, R. Larry
Saperstein, Lee W.
Tien, Jerry C.
Van Aken, David C.

Department(s)

Mining Engineering

Degree Name

Ph. D. in Mining Engineering

Publisher

University of Missouri--Rolla

Publication Date

Spring 2006

Pagination

xiv, 147 pages

Note about bibliography

Includes bibliographical references (pages 133-146).

Geographic Coverage

Athabasca Tar Sands (Alta.)

Rights

© 2006 Kwame Awuah-Offei, All rights reserved.

Document Type

Dissertation - Restricted Access

File Type

text

Language

English

Subject Headings

Excavating machinery -- DynamicsBlasting

Thesis Number

T 8836

Print OCLC #

74840301

Share My Dissertation If you are the author of this work and would like to grant permission to make it openly accessible to all, please click the button above.

Share

 
COinS