A non-queue-based paradigm in Discrete-Event-Simulation modelling for construction operations

Discrete-Event Simulation (DES) is an event-driven simulation approach in which a real dynamic process is imitated as it progresses over time. It has been recognized as a powerful technique for the quantitative analysis of complex construction operations. However, current DES modelling strategies/frameworks implicitly rely on queuing structures which are too rigid to easily describe systems with complex behaviour common in construction, e.g., multi-tasking resources and/or role changes of entities. Queuing networks are one of the most common elements of DES systems and have been used to model a wide range of problems, but they lack the generality to easily model the complex decision mechanisms required to, e.g., efficiently multi-task or dynamically determine the best role for an entity. This research proposes a new modelling approach for construction that replaces Queue-Based (QB) DES, with its implicit queuing network control, with Non-Queue-Based (NQB) DES that explicitly defines the decision mechanisms of a model. It utilises a new conceptual modelling paradigm for simulation, Hierarchical Control Conceptual Modelling, which was developed to address similar issues with control mechanisms in health care simulation. This new approach is especially beneficial for the construction industry where determining effective decision making mechanisms is of significant importance for optimising, e.g., logistics and resource utilisation. This research investigates the benefits of the proposed approach for DES models in construction by investigating three earthmoving case studies. Although the scope of this research is limited to DES modelling in construction, the outcomes of the proposed NQB paradigm in construction translate to other domains that utilise DES for solving complex problems.