RFID-based quality and safety building site improvement during execution phase

Nowadays, construction projects are typically carried out by several main contractors as equal partners and dozens of subcontractors, mainly SMEs, organised in hierarchical contractual and responsibility structures of several subcontracting levels. Hierarchical centralized planning down to individual tasks with exact time scheduling is also done in advance, but due to the high networking complexity and, especially, the multi-project participation of many of the actors this often leads to very high planning risks with regard to resources and time. Moreover, many ad-hoc decisions are taken by the project manager on the job site, without a proper update of the process plan. Due to this very common scenario, there are two specific issues that need to be put at the front of the 21^st century construction site: quality and safety. To achieve that, capabilities for distributed teamwork management and on-site decision making are required, coupled with adequate services enabling just-in-time goal-driven information delivery and capable to support the needed on-site dynamicity in terms of quality assurance and safety on site management. Two specific technologies which were used in other sectors during the last decades, such as RFID have shown to be powerful enabling technologies for construction sector. As it will be explained in this article, three applications have been implemented by ACCIONA in its sites. On one hand, RFID tags have been used to assure safety inside tunnels during its construction, tracking workers location. On the other hand, an RFID-based wireless sensor network has been deployed in order to remotely monitor concrete mechanical properties in real time, being able to optimize execution times of all the successive construction phases (excavation under a slab, advancing in shuttering truck tunnels, etc).