CONSOLIDATING AND PROTECTING RC AND PRC STRUCTURES.
Most of the edifices built in the aftermath of the Second World War, particularly between the 1950s and 1970s, at a time when anti-seismic regulations were still lacking, are made of reinforced concrete and specially designed to stand the action of gravitational loads. Because these buildings feature very irregular mass and stiffness distribution, pillars with a poor resisting section and over-sized, scarcely ductile beams often made with poor quality materials, their maintenance and seismic improvement and upgrading are particularly troublesome.
More problems forth come from the degradation of reinforcing bars, which are highly sensitive to corrosion, especially if associated to porous or inadequately compacted concrete, inadequate concrete cover and extremely harsh conditions, e.g. brackish air or water, high content in salts or other chemically aggressive substances. As a matter of fact, large-sized RC and PRC works – e.g. bridges, viaducts and similar infrastructures – are frequently affected by concrete carbonation, which causes the metal reinforcements to corrode and lose their resisting sections and, as a consequence, large areas of the concrete cover tend to peel off. Among various systems aimed at consolidating existing structures, Fibre Net developed a special FRP range for the fibre-reinforced sheeting method, which is especially suitable to consolidate, improve the seismic resistance of RC and PRC beams, pillars and frames.
Developed to protect the main reinforcements against chemical aggression, the FIBREBUILD FRCM (Fiber Reinforced Cementitious Matrix) system, consisting of GFRP meshes and accessories, provides an efficient superficial reinforcement which, combined with adequately selected structural mortars, helps rehabilitate the sections and improve the mechanical characteristics of any damaged element.
Fibre Net systems guarantee efficient and durable consolidation, with improved mechanical resistance, ductility and stiffness, while keeping loads and thickness of reinforcement low.
REINFORCED RENDER METHOD
The corrosion of superficial reinforcing elements is a most frequent mechanical degradation found in modern RC and PRC buildings, and particularly in structures exposed to aggressive weather conditions, e.g. brackish air and water, and to chemical agents. Corroded bars cause portions of mortar cover to fall off and, as a consequence, speed up and worsen the process of structural degradation.
Rehabilitating and protecting degraded RC and PRC structures with FIBREBUILD-FRCM system consists in passivating all surfacing bars and then coating them with suitable mortars reinforced with GFRP meshes and connections. Their great mechanical resistance and chemical inertia help obtain durable and efficient consolidation of the whole structure, improving and protecting the whole structure.
• LIGHTWEIGHT BUT HIGHLY RESISTANT
• CORROSION-PROOF, EVEN UNDER EXTREMELY CORROSIVE CONDITIONS
• NON-MAGNETIC (NO “FARADAY CAGE” EFFECTS)
• REDUCED WEIGHT AND THICKNESS
• REINFORCING BARS ARE PROTECTED AND SECTIONS REHABILITATED
• EFFICIENT AND DURABLE CONSOLIDATION
• DIFFUSED AND HOMOGENEOUS MECHANICAL IMPROVEMENT
• SIMPLE AND RAPID INSTALLATION
• REDUCED HANDLING, INSTALLATION TIME AND COST
• REDUCED TOTAL INTERVENTION COST
• SAFE WORKING ENVIRONMENT
FIBRE-REINFORCED SHEETING METHOD
Structural degradation and reinforced concrete elements insufficiently sized to stand seismic action do not guarantee adequate mechanical properties and ductility.
FIBREBUILD-FRP reinforcements, consisting of glass fibre and carbon fabrics glued with thermosetting polymer resins, help improve shear, flexural and compressive strength of beams and pillars. The system allows reinforcing individual spots and hooping the most sensitive areas, e.g. beam-column joints, inter-floor and top curbs. The works are carried out in-situ, by carefully choosing the amount and arrangement of the fibres with a view to maximizing the mechanical properties of the reinforcement according to the special needs of the intervention.
• GREAT MECHANICAL PROPERTIES
• CORROSION-PROOF AND COMPATIBLE WITH LIME AND CONCRETE BASED MORTARS
• EXTREMELY THIN
• EFFICIENT AND DURABLE CONSOLIDATION
• MECHANICAL IMPROVEMENT WITH TARGETED CONSOLIDATION OF INDIVIDUAL SPOTS
• REINFORCEMENT CAN BE SIZED TO SPECIFIC DESIGN
• REINFORCEMENT CAN BE ADAPTED TO IRREGULAR SHAPES
• NON-INVASIVE CONSOLIDATION