Content area
Abstract
Construction, with its uniqueness and unusual operational characteristics, faces special handicaps dealing with process planning and control. To study the productivity and the resource efficiency of construction operations, one has to consider the impact of a wide variety of factors. For the analysis of such complex systems, quantitative methods are sought.
The CYCLONE (CYCLic Operations NEtwork) technique presents an analytical means for modeling and simulating construction processes. It considers the logical relationship between work tasks, their durations and the number of resources. CYCLONE determines process productivity and the effectiveness of resource utilization.
The productivity of repetitive and balanced systems is considered to be in steady-state when its variation is marginal. The literature about digital computer simulation discusses mostly steady-state performance while real world processes are most frequently not steady. Especially in operations which take place on a construction site where work places constantly change, etc., delays occur often.
The storage of raw material and process units creates the opportunity to continue the production while a particular work task is interrupted by providing necessary resources.
This thesis develops a systematic framework for the identification of delay causing factors. It focuses on the study of the relationship between storage limitations for flow units and process production. Enhancements to the existing CYCLONE simulation program which allow the analysis of storage conditions as well as the effect of break-down delays on productivity are presented.
The analysis shows that generally higher storage contraints result in higher overall productivity. However, the different structures present specific conditions where the general rule does not apply. System constraints, the randomness of digital simulation and bulk arrivals in storage areas are factors which must be considered in the analysis of simulation results.
Digital simulation techniques provide the means to model and to study construction processes. This research exhibits how the existing CYCLONE technique can be enhanced to allow the simulation of an even wider variety of real world situations.