Optimisation of tower crane usage in planning of precast construction projects

Abstract

Cranes take indispensable role in construction operations. It is popularly seen tower cranes in high-rise, congested urban building construction, or mobile cranes in heavy civil and infrastructure construction. Cranes usage has profound effects on the completion time as well as the profitability of the project. Therefore, the choice of the crane and its optimum location on a site is seen as the one of the most important parts of construction planning. Optimizing the crane usage can be divided roughly into two main phases (1) selecting the suitable type of cranes and (2) choosing the particular model(s) with considerations to the crane configurations, its location, supply points and other site constraints. A computer program using genetic algorithms (GAs) has been developed to assist in the selection and positioning of tower crane(s) on the construction site with quantitatively evaluations of its (their) total hoisting time. The program is capable of dealing with multiple tower cranes and multiple supply points, and taking into account the crane configurations of different models in the databases.