Application of computer simulation to construction of incremental launching bridges

Abstract

Construction of bridges is associated with uncertainties that rise due to unavailability of resources, equipment breakdown and/or working environment. Bridge construction techniques can be grouped into six main categories: 1) castin-situ on false work, 2) cantilever carriage, 3) stepping formwork, 4) launching girder, 5) pre-cast balanced cantilever, and 6) incremental launching. The latter technique is characterised by minimising the use of falsework. Further, the fabrication and casting of bridge segments are executed at a stationary location, named casting yard (which includes several facilities), deck form, concrete mixing unit, and pumping system. This paper presents a special purpose simulation model to capture the uncertainty associated with bridge construction. The model accounts for the interaction between the different involved resources in construction of bridges using incremental launching technique. The paper describes two methods (single form and multiple forms) of execution used for the segments fabrication. The proposed simulation model utilises STROBOSCOPE as a simulation engine and is coded by Visual Basic 6.0. An actual case study is presented to illustrate the capabilities of the developed model and validate its performance.