Structural reinforcement of masonries with CRM systems
CRM (Composite Reinforced Mortar) systems represent a modern evolution of the traditional technique with reinforced plaster. In past decades, the reinforcement technique of masonry load-bearing structures with reinforced plasters spread, using often cementitious reinforced grouts with steel electro-welded meshes. Over the years, this technique has showed its limits and often appeared to be even harmful for the pre-existing structure.
The new CRM systems of the Olympus STONE line allow for interventions compatible with masonries and not resulting in specific criticalities. The CRM system features by definition a 30 to 50 mm thickness net of the eventual smoothing of the support.
CRM reinforcement systems of Olympus STONE line consist in:
Preformed meshes obtained from the impregnation of glass fibers resistant to alkali. The meshes function as boosters of the tensile strength and confinement of the members to be reinforced;
Preformed glass fiber mesh-shaped angular guards obtained with the same materials and the same production process of meshes whose function is to convey a structural continuum at the corners;
Preformed glass fiber connection members resistant to alkali and obtained with the same materials, whose function is to connect the reinforced plaster with the masonry member and the reinforcement applied on the opposite face of the latter, if the case;
Cementitious or lime-based mortars with a guaranteed structural performance;
Chemical bolts to fasten the connectors between each other or anchor them to the masonry support.
Olympus STONE CRM line
Possible employs
CRM Olympus STONE line composite materials are used for structural reinforcement interventions of pre-existing buildings.
Thanks to their mechanical, physical and chemical properties, these systems are particularly fit for the structural reinforcement of load bearing walls.
They can also be used in seismic adjustment or improvement works or to locally fix some structural gaps.
Below are the possible most common employs based on the type of structure to be reinforced.
a) Consolidation works on masonry members
Masonry panels → shear and flexural reinforcement for in-plane actions
Masonry panels → shear and flexural reinforcement for out-of-plane actions
Masonry Macro-members → prevention of local failure mechanisms
Masonry columns → confinement
b) Consolidation works on deckings
reinforcement of masonry deckings → any type of vaults and domes
Advantages
CRM systems convey several advantages also compared to other types of composite materials. These advantages are brought by the high-strength conveyed by the fiber-component and the use of synthetic matrices and they are:
- High mechanical strength;
- High durability over time;
- Reinforcements without any significant additional weight;
- Possibility to use synthetic matrices compatible with the masonry to be reinforced;
- Guarantee of breathability of masonry;
- Fire resistance;
- Easy lay-up by the workforce.
All the above advantages make the CRM systems an excellent structural reinforcement technology for load-bearing masonry members. CRM systems can be applied on any type of masonry.
Testing
OLYMPUS STONE line CRM systems were involved in more than one testing campaign by University laboratories and National research centers.
After the tests conducted the CRM systems obtained the compliance with the Guidelines of the Higher Council for Public Works.