Monitoring segment production and installation 18 Oct 2018

Smart technology is being used ever increasingly for current and future monitoring of underground infrastructure. An important and specific application of the technology is for the monitoring of the segments manufactured for the one-pass lining and support of infrastructure projects.

Scanners link via a wireless network to the SDS database

Leading the technology is the segment documentation system (SDS) developed and supplied by VMT. Each segment produced is fitted with radio frequency identification (RFID) tags and bar codes so that segments can be tracked throughout the production process and then monitored throughout their lifespan in situ. The system documents all the major processes within the production and storage of segments and captures their position and installation data in the tunnel to manage plannable, efficient, transparent handling on site.

More than a documentation system, SDS is an integrated solution that ensures compliance with quality and documentation standards to optimise use of resources, exclude risks, avoid errors and reduce costs. The system links all areas of the tunnel site to an intelligent, efficient workflow network and collects detail data to allow production of a report of all the necessary information relating to the quality and combination of raw materials used in each segment produced. This data is checked by staff in the segment production line and by project managers before being added to the database that contains a complete report on each individual segment. The system can be adjusted as required so that customer specifications and guidelines are followed and implemented in all stages in the process.

Segment production is monitored using bar codes and RFID tags

A significant application of the system currently is on the Santa Lucia highway tunnel project in Italy where a 15.87m diameter Herrenknecht EPBM is excavating and erecting the segmental lining of a single 7.5km long tunnel. The tunnel is one of several on a 59km long section of the A1 Autostrada in Italy which is currently being upgraded and widened in four sections with construction of three new lanes for southbound traffic with the existing four lane highway becoming ultimately the northbound route.

The Santa Lucia tunnel is being built through the Apennine mountain range by contractor Pavimental which is a JV owned by Atlantia, Autostrade per l´Italia, Aeroporti di Roma and Astaldi. The 15.87m diameter machine has been designed to bore through heterogenous geology of the mountainous region using a drive power of 8,750kN and a torque of 101,296kNm.

Segment casting yard for the Santa Lucia project

Segments prepared for building into the highway tunnel

For production of the 32,000 segments required to line the tunnel, the client and contractor subcontracted Italian construction and precast company Maccaferri to fabricate and supply from a precast segment factory based in nearby Bologna. To meet the challenges of high quality standards and the application of RFID tags as specified in the tender to manage control of the process, the manufacturer decided to work with the SDS system from VMT.

“The decision to manage the production and the logistics storage through an integrated system came from the need to produce and document a range of elements,” said Valeria Mainieri, Quality Manager with Maccaferri. “The alternative was to employ several workers that would be stationed along the production line in order to collect the production data required. This could have led to human error. It also meant that we could meet the customer requirement to install and monitor RFID tags into the liner segments.”

“The SDS system allows us to manage the production process along with detecting some of the parameters linked to the traceability of materials,” added Mainieri. “The fact that we could customise parts of the system meant we were able to drastically reduce the use of resources allocated to data input on the client side of the process, which was one of the requirements demanded by our customer Pavimental.”

Lining is being installed by the 15.87m diameter EPBM

In setting up the system, VMT provide training of segment fabrication workers, staff and management and remain on hand should further service be required.

“Despite the usual communications difficulties where manufacturer and client work in different languages, our collaboration with VMT, both in the negotiation stage and in the implementation phase has been both profitable and direct,” said Mainieri. “During the production phase VMT was always available for support. Once trained in the system our operators seldom had to call on the VMT team to assist, but we always knew they were available if needed.”

Mainieri concluded that: “The system is certainly well built and solid and while the final outturn cost is not always as might be preferred, the system had the flexibility to be adapted and integrated with any changes in the production process, even after segment production had started. This allows the system to fit with the production process and in particular to the part dedicated to the segment storage system.”