Equipment selection and on-site utilization for heavy industrial projects

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The oil sands industry is currently one of the strongest driving forces of Canadian economy. Recent statistics indicate that Canada is the third-largest oil reserves in the world, after Saudi Arabia and Venezuela with an estimated reserve of 174 billion barrels of which 170 billion are located in Alberta in the form of oil sands (Alberta Government, 2012). Because the Northern part of Alberta is known for its harsh and long winter, heavy construction faces stringent time constraints and because of that modular construction emerged as the solution of choice for large scale projects. However, as modules evolved to be heavier (sometimes in excess of 500 metric tons) and more voluminous their on-site assembly requires mobile crane. As a result of the industry embracing the concept of modularization, the challenge of heavy construction shifted from fabrication to assembly thus making crane operations one of the critical factors that could impact efficiency. A close examination of crane operations, especially from the view point of practitioners, shows that path planning is a challenging task especially for large scale projects which makes its automation indispensable to ensure fast responses to change in work orders or in the scope of the project. The proposed research aims at developing a holistic methodology to crane operations which integrates site layout, path planning and module assembly sequencing. The proposed research departs from previous work on two main elements: (i) in contrast to other studies in which paths are represented by polylines, the proposed research builds such trajectories as a sequence of rotations and translations which are the only fundamental motions of cranes; (ii) because installed modules may become obstacles for subsequent lifts, it is important to analyse the order in which modules are assembled so to maximize the area where a mobile crane can maneuver. This leads to a better utilization of mobile cranes since an optimal sequencing of modules reduces the need for crane walking or re-allocation which occurs when obstacle-free paths could not be found. However, to be complete the proposed research also addresses the issues of path planning in the case where the crane is required to walk while carrying the load.