One of the major projects currently underway in Italy is the Pedemontana Veneta Expressway, 94km from the Province of Vicenza to the Province of Treviso (Northern Italy), that will help reduce the level of traffic on the A4 Turin-Venice motorway. It will end up linking to the A28 motorway. Of the 90km of road, 50km will run through cuttings, 26.5km will run along embankments, 7.8km will run through natural tunnels and 5.6km will run through artificial tunnels. Reinforced concrete will be used for the walls and decks of the artificial tunnels and to build the retaining walls to shore up the cuttings.
The estimated volume of precast concrete required for the whole of the Pedemontana Veneta Expressway is around 1 million m3, while the amount of ready-mixed concrete required will be around 2 million m3 (source: Sis).
Numerous Mapei products have been used to construct this important link on the Italian roads network. The concrete mixes for all the precast structures include the super-plasticiser Dynamon NRG 1022 and the concrete will be stripped with the help of Mapeform Eco Oil form release agent.
Ready-mixed concrete has been admixed with the superplasticizers Dynamon SX 44 and Dynamon SX 42 with added aerating agent Mapeplast PT1 for concrete resistant to freeze-thaw cycles. The lanes for the toll booths have been made using concrete admixed with Mapetop N AR6 pre-blended, ready-to-use dry shake hardener along with Mapecure E curing compound to prevent rapid evaporation of water in concrete.
The load-bearing concrete walls for the toll booths have been covered with rough-cut natural stone bonded with Elastorapid adhesive, while joints have been grouted with Mape-Antique Allettamento mortar and expansion joints have been sealed with Mapesil LM neutral silicone sealant. Malech undercoat and Elastocolor Paint have been used to finish off precast concrete surfaces along the sides of the expressway.
The main tunnels have been built using the plasticizing and expanding agent Cablejet for preparing shrinkage-free, highly-fluid pumpable slurries for injection, as well as Mapequick AF1000 alkali free accelerator for shotcrete in combination with Mapefibre CN54 structural polypropylene fibers and Mapeform Eco Oil.
The firefighting tanks used to collect rainwater have been waterproofed with Mapelastic Foundation, while some of the concrete partition walls have been waterproofed with Planiseal 88 osmotic cementitious mortar. As for the viaducts, the following products were used: Mapegrout SV Fiber flowable, shrinkage compensated, quick setting and hardening, high-ductility cementitious mortar; Adesilex PG1 two-component, thixotropic epoxy adhesive for structural bonding; Planibond BA 100 two-component fluid epoxy resin for anchoring steel bars and Mapefloor EP90 three-component, epoxy screed consistency mortar.