Simulation of a longwall development extraction network

CIM Bulletin, Vol. 80, No. 903, 1987

SUKUMAR BANDOPADHYAY and ARUNAPURAM SUNDARARAJAN, Department of Mining and Geological Engineering, University of Alaska, Fairbanks, Alaska

For the last three decades, the application of network planning has provided a basis for a formal and general approach to the discipline of project management. For fixed activity duration, a very simple algorithm commonly known as critical path method (CPM), gives the length of time required for the total project as well as indicates the activities which are vital to the completion of a project. Project Evaluation Review Techniques (PERT) on the other hand, generalize the above approach to recognize uncertainty in the activity durations by allowing them to be random variables. One of the misleading aspects of current "PERT" solution method is, however, the implication that there is a unique critical path. In general, any number of paths could be critical, depending on the particular realization of the random activity durations that actually occur. In this case, simulation can be utilized to estimate completion time of a project. In this paper, the concept of criticality indexing is discussed, and a simulation model application which defines the critical path based on the criticality indexing concept, to a longwall development - extraction network, is presented. The model also provides suitable scheduling of resources based on the resource constraints and smooths out period-to-period assignments.

Keywords: Simulation, Longwall development, Project management, Modelling.