Flexible assembly methods

Report, 2013

There is today an increasing need for replacement of bridges in Europe due to aging infrastructures and increasing traffic. A large proportion of these bridges is located in urban environment or on important traffic routes, sensitive to nuisances such as noise and vibrations or to traffic disruptions, which are frequently inherent in construction works. In this context, PANTURA project aims to equip authorities and other stakeholders with methods, tools and techniques to enable bridge construction to be carried out in the most efficient and sustainable way. One of the means to reach this goal is through the improvement of off-site production and on-site construction processes. A wide range of technical solutions from prefabrication, ICT and robotics have been identified in this study. Many of these solutions or the materials they are based on are commonly used in production and manufacturing in other industries but scarcely in construction. Others have already been applied with success in civil engineering projects in some countries and would deserve wider diffusion. By analysing different innovative solutions using the SWOT approach, strategies have been presented to overcome their remaining weaknesses and to gain acceptance for them by the different actors of civil infrastructure projects. The use of prefabricated elements produced off-site and transported to the bridge site for assembly can be beneficial in terms of costs, construction time and social impact. Nevertheless, it sets high requirements on the assembly process. When using prefabricated elements flexibility decreases compared to traditional on-site bridge construction and late changes become harder to implement, therefore requiring a good planning to have an even flow at the site and to avoid unexpected events. With that in mind, the different stages of the assembly process have been studied to identify the critical issues. Based on these critical issues, precise procedures were developed for different aspects of urban construction. ICT technologies, assembly techniques and organizational patterns are proposed to enhance and optimize the processes existing within a construction site. Concepts such as logistics optimization, storage space rationalization or technological worker safety enhancement were thoroughly studied and ideas for improvement have been proposed as a result of the analysis. The procedures have been developed to integrate all the different activities during the building process, while seeking to avoid unwanted interferences between them. Through the application of the PANTURA procedures, construction sites can be turned into high-tech areas, where processes are streamlined, safety is paramount, nuisances are minimized, and latest advances in ICT technologies are used to facilitate coordination and management. This in turn will allow achieving a high degree of effectiveness during the construction process and as a logical consequence lead to the success of the projects.