|M.Sc Thesis||Department of Civil and Environmental Engineering|
|Supervisor:||Assoc. Prof. Shapira Aviad|
The selection process of construction equipment is complex, and conventional methods, such as optimization tools, expert systems or economic comparisons, frequently cannot provide the desired solution.
A comprehensive literature survey has uncovered the various selection factors of construction equipment, along with the drawbacks and limitations of existing models and selection methods. Within this thesis a comparative analysis is presented, that summarizes and highlights the body of knowledge on equipment selection models.
Selection of equipment for construction projects generally involves two classes of considerations. The first class comprises tangible, quantitative, formal considerations. The second class covers a medley of ample "other" factors, which mostly are intangible, qualitative and informal in nature.
Factors of this latter class are by nature much more difficult to deal with. It is, however, clear that these factors frequently play a dominant role during the decision-making process, and therefore are worthy of investigation.
Existing models are predisposed to be restricted to sub-problems of the general equipment selection problem, make simplifying assumptions, and are all found to lack the capability to integrate qualitative and intangible factors in the solution and to deal with uncertainty and subjectivity.
Within this study the role of intangible considerations in the selection of construction equipment was emphasized, and an Analytic-Hierarchy-Process- (AHP-) based model was developed with a focus on building projects. Model development included two main parts: (a) An AHP-based module to evaluate equipment alternatives in relation to intangible factors, yielding a benefit score for each alternative; and (b) an aggregation module to combine the costs and benefit scores of the considered alternatives.
The proposed model was validated through a series of case studies, and is, in effect, a formalization of good practice in equipment selection. Underlying the important role of intangible factors and systemizing the process of equipment selection, the model provides a significant contribution to the ultimate goal of successful selection of equipment, recognizing the impact this may have on the overall success of the project.