Reinforced plasters - CRM System
Fibreglass mesh reinforced plasters and specific mortars for repairing and strengthening masonry structures.
Consolidating masonry, using the reinforced plaster technique, represents one of the solutions indicated in Italian Ministerial Circular No. 7 of 21/1/2019 for increasing the load-bearing and anti-seismic resistant capacity of existing walls.
This solution is particularly effective in the case of severely damaged or discontinuous masonry, provided the necessary transverse connection elements are installed and anchored securely to the reinforcement on both sides of the masonry.
Ruregold reinforced plaster is realised using the CRM masonry strengthening system, consisting of the following elements:
- G-MESH 400/490/1000 preformed GFRP alkali-resistant impregnated GFRP fibreglass meshes;
- Connection system consisting of HELICAL CONNECTOR helical, stainless steel bars or, alternatively, G-MESH CONNECTOR preformed, A.R. glass fibre elements;
- G-MESH GUSSETS for distributing the stress concentrations across the connection systems;
- Structural plaster mortars: high pozzolanicity hydraulic binder-based (MX-RW High Performance), cement based (MX-15 Plaster) and lime-based (MX-CP Lime), obtained using premix technology.
Structural repairs without reinforcement with fibre-reinforced mortar:
By using MX-PVA Fibre-Reinforced mortar, with its excellent mechanical performance and ductile performance specifications, it is to avoid the need to use the sort of extensive reinforcement that typifies traditional reinforced plaster solutions and/or innovative CRM systems.
When determining the improvement coefficients to be adopted when using MX-PVA Fibre-Reinforced mortar, it is important to take into account the mechanical characteristics that were identified during an extensive series of experimental tests conducted by the University of Perugia; we also recommend the use of transversal connection systems, such as HELICAL CONNECTOR, or C-BAR or G-BAR pultruded FRP rods (together with MX-JOINT mortar for insertion into the perforation).
Alternatively, B-JOINT fibre connection systems may also be used.
In order to assess the significant technical contribution of MX-PVA Fibre-Reinforced mortar, a series of diagonal compression tests were conducted on unstrengthened masonry samples, compared with similar samples strengthened with 2.5-3 cm of MX-PVA Fibre-Reinforced mortar, without any form of transversal connections.
On the basis of the resulting mean resistance values, it may be seen that the shear strength of masonry strengthened using MX-PVA Fibre-Reinforced mortar is increased by a factor of approximately 1.85 with respect to unstrengthened masonry.
