Resource Leveling of Railway Track Construction Operations Using the Linear Scheduling and Genetic Algorithm Techniques


Damcı A. , Polat G.

2010 International Conference on Construction and Real Estate Management, Brisbane, Australia, 1 - 03 December 2010, pp.105-110 identifier

  • Publication Type: Conference Paper / Full Text
  • City: Brisbane
  • Country: Australia
  • Page Numbers: pp.105-110

Abstract

Since management of construction projects in terms of time, cost and quality has been highlighted, the development of scheduling methods was inevitable. Activity-based scheduling methods (i.e., critical path method, etc.) were predominantly used for construction scheduling. However, this situation is now changing rapidly for several reasons. For instance, activity-based scheduling methods were found to be inadequate for linear construction projects due to some shortcomings, such as: (l) Difficulties in visualization of a network which consists of repetitive activities; (2) The primary goal is minimizing the project duration rather than dealing with time/space conflicts and resource constraints, etc. Due to these shortcomings, an alternative methodology, which is called location-based scheduling, has been developed. It is commonly claimed that the linear construction projects, which are repetitive in nature, are well suited for location-based scheduling methodology. Nevertheless, selecting the appropriate scheduling technique is not enough to complete a project successfully. Construction companies should schedule their projects in a manner that considers the efficient use of limited resources in order to remain competitive in today's global construction market. In this context, this paper mainly discusses the resource leveling problem of a railway track construction, which is a linear construction project, by using the linear scheduling and genetic algorithms. The railway track construction operations mainly consist of five consecutive processes, which are: (1) The placement of the first layer of ballast; (2) Laying down preconstructed rail panels; (3) The placement of the second layer of ballast; (4) Tamping and stabilizing; (5) Flash butt welding. A genetic algorithm based model is developed in order to minimize the sum of the absolute value of the deviations among resource requirements on any day and thereby achieve a desirable resource utilization rate, without changing the total completion time of the aforementioned activities for a railway track construction. The proposed resource leveling model attempts to improve a linear schedule.