Skip to main content

Major Pisa link gets upgrade

Recycling with foamed bitumen is being used for lane reconstruction on the SP11 road in Italy, where contractor F.lli Lepri is carrying out work on a 14km section. The SP11 is an important link forming part of the Colline per Legoli Highway connecting the SS67 Tosco-Romagnola Highway near Pontedera with the southeast region of Pisa Province up to the borders of Florence Province.
February 29, 2012 Read time: 3 mins
Recycling with foamed bitumen is being used for lane reconstruction on the SP11 road in Italy, where contractor F.lli Lepri is carrying out work on a 14km section.

The SP11 is an important link forming part of the Colline per Legoli Highway connecting the SS67 Tosco-Romagnola Highway near Pontedera with the southeast region of Pisa Province up to the borders of Florence Province.

The contractor is using a technique that meets Italian standards to client Pisa Province’s specification. The aim of the work is to improve the surface quality by repairing damage to the existing road.

Cold recycling has been used with foamed bitumen on sections with clearly identifiable damage and cracks in the surface, to produce a road surface 200mm thick. This features an 80mm asphalt binder layer and a 40mm asphalt wearing course. Cold recycling has been used to a depth of 100mm on those sections with less damage.

The cold planer makes an additional pass while any additional material, additives and foamed bitumen is sprayed into the mixing drum. Micro-processor controls ensure optimum metering of the sprayed additive when mixing with the pulverised material.

The processed material laid behind the machine is pre-compacted by a heavy screed and is followed by profiling with a grader and further compaction. By adding foamed bitumen, mixed material made from different natural additives or asphalt granulates can be turned into high-quality roads.

172 Bomag has developed the MPH125 recycling unit in collaboration with contractors and says that the machine is efficient and reliable and offers high performance for mixing lime, fly ash and cement for soil stabilisation. For cold planing, the unit can be used in multiple applications to pulverise old and damaged roads to stabilise the road.

The speed of the rotor is adjustable to match the job while the mixing drum adapts automatically to milling depth, the type of soil and materials used. Binder and soil can be processed to form a uniform mix with minimal wear and optimised energy consumption.

A high quality mix is created from the recycled materials when combined with water and binding agents and the new asphalt binder layer features good mechanical properties while the road's bearing capacity is improved, so there is no need to use reinforced structures. The uniform single-layer binder courses contain no weak points and there is less stress on the sub-base.

A recycling train can work in a single lane so that reconstruction can be carried out on half the carriageway and the entire road can be opened up again for traffic at the end of the shift.

A BOMAG Terrameter can carry out tests during cold recycling while work is ongoing. This unit automatically tests the bearing capacity of the asphalt layer during compaction, after which dynamic plate tests are applied.

Cold recycling can offer fast road repairs and as long as processes are adhered to, the technique offers a road repair with good mechanical properties and a long projected working life.

For more information on companies in this article

Related Content

  • No compromise with FAE’s STABI/H stabiliser
    May 5, 2021
    The STABI/H is FAE's top-of-the-line professional stabiliser for the construction market.
  • Bitumen technology suppliers seek new ways to save money and work more efficiently
    April 24, 2013
    When World Highways decided to ask some of the industry’s leading suppliers what the future holds for bitumen, we found out - not surprisingly in the current economic climate - that it’s all about saving money. Kristina Smith reports. How quickly the tide turns. Just two years ago, saving carbon and the planet was moving up many countries’ political agendas. Now politicians in Europe and beyond have been forced to park commitments in the face of economic austerity. “The big issue with local government is th
  • Dual layer, hot to hot paving at German airport
    August 18, 2015
    An airport in Germany has seen the use of very innovative asphalt paving techniques, with the use of dual-layer, hot-to-hot working. The method was used to meet a very tight schedule for the runway rebuilding work, while also delivering the high quality required. Two InLine Pave trains from Vögele were used at Rostock-Laage Airport to lay a new surface and binder course. The operation was innovative as the process used both hot-to-hot, echelon paving as well as dual layer, hot-on-hot working. Using this
  • Durability is crucial while warm mix technology can help disaster recovery
    February 21, 2013
    Why durability is crucial for both emerging and developed economies, and how warm mix technology can help disaster recovery - Kristina Smith reports. When CORE Construction, a 100% owned Ghanaian company, started working on road construction projects five years ago, it was difficult to source the right bituminous mixes. “In the past, most construction firms had a number of challenges when it came to bituminous works, since the local capacity was not well-developed,” said CORE CEO Frank Lartey. CORE’s soluti