Using a PERI climbing formwork solution precisely tailored to meet the project requirements and reduced material requirements, nine silos grew steadily upwards in regular 2-week cycles. Ready-to-use elements supplied directly from the PERI formwork assembly hall ensured dimensional stability.
Rising 52 m high into the sky, the recently completed nine grain silos have significantly expanded the storage capacity for the Molino Agugiaro & Figna Collecchio company which is based near Parma. The circular silos, with a 7 m inside diameter and 25 cm wall thickness respectively, are connected to each other and are positioned on a 5.45 m thick reinforced concrete foundation. 1,350 tons of wheat can be stored in the silos; a neighbouring building constructed at the same time houses the new cleaning and grinding plant which has a daily production of 30 t.
Reduced on-site material requirements
In order to maintain the tight 8-month construction schedule as well as ensuring optimal building progress, PERI engineers combined a complete platform level on the basis of the CB climbing system with the amount of wall formwork reduced by half. as a result, rapid and continuous working operations – reinforcement, forming, concreting – could be achieved with reduced on- site material requirements. The concept, with 16 climbing cycles and 3.25 m concreting cycle heights in each case, took into account that only one crane was available and could not be worked around the clock.
The CB climbing system ensures safe working operations with wall formwork at all heights. The well thought-out construction combines easy handling together with a fast moving procedure and problem-free adaptation to suit different building shapes. The high load-bearing capacity of the brackets facilitates the use of large scaffolding units – this saves on time-consuming tie points and the time required for climbing. With the CB 240 system, the strongbacks are connected to the brackets by means of a formwork carriage mounted on roller bearings together with a rack and adjustable braces. A retraction distance of approx. 75 cm creates an obstacle-free working area in front of the formwork. The decking of the CB 160 is only 1.60 m wide – here, the formwork is tilted, which is connected by means of an adjusting unit and adjustable braces.
Ready to use pre-assembled
VARIO GT 24 girder wall formwork elements were used to form the silo walls, and the formlining for the 3.50 m and 3.75 m internal and external radii respectively was adapted to suit the curvatures by means of shaped timber formers. These were accurately pre-assembled at the PERI assembly facility and delivered ready-to-use to the jobsite. Tight connections were ensured by using articulated couplings which also meant that the formwork elements could easily be positioned. In addition, the site-compliant PERI implementation planning took into consideration efficient striking procedures within the constraint points between the silos.
88 CB climbing platforms with CB 160 brackets on the internal and CB 240 on the external sides formed one complete working level. Including the finishing platforms on the CB brackets and concreting scaffolds on the internal formwork, optimum accessibility and safety was ensured on three levels. The access and safety concept was complemented by a steel staircase on the basis of the PERI UP Rosett Flex modular scaffolding system. Mounted as a 10-legged tower, access could quickly be adapted to suit the construction progress right through to the final staircase height of almost 40 m. Here, the lightweight individual steps were quickly mounted on the stringers without requiring any tools: they interlock during installation and are immediately secured.
The 1.00 m step widths of the PERI UP Rosett Flex Steel stairs together with separate landings provided site personnel sufficient space also when simultaneously using the stairs in both directions. Furthermore, the stair tower construction is designed for a high load-bearing capacity of 3 kN/m². Toe boards on the landings and closed risers reliably prevented any small parts from falling to the ground.