sismoplaque

This type of sheet allows an inertia of the building or mass (machine, turbine, column, pool…) in relation to the ground or foundation hitten by seismic events or vibration waves.

The concept is made of three parts:

1) A, connected to the supporting substrate, foundations, apron, slab, metallic structure.
2) B, rounding the plate or adding a slab which is thus untouched by seismic events, vibrations or accelerations which threaten to destroy the elements above the latter.
3) B between these two elements: balls whose resistance is defined by the load applied by the elements above.

The concept’s components: mainly HR steel which has been machined, milled or cast.
The steels’ quality is defined by the working loads.

Its principle is to work as a flat ball bearing.

The A piece and the B piece are defined by section plates which vary according to the situation and whether it is a new construction or an existing building going into protection.
Each sheet has a minimum thickness of 12 mm, manufactured on the half thickness with circular openings whose diameter depend on the shifting observed regionally and retrospectively (summary FR BRGM). The two sheets are placed one on another so as to form « boxes » containing a ball which positions itself at the center by a slight boss or hollow cone milling.

As to its sizing, the product design remains dependent on the displacements, the magnitude, the load-lowering and the size and shape of the future or current building.

The patent can apply to occasional concepts with a bell jar containing a ball and a counterpart called ball bearing stage.
Various developments make it possible to respond to earthquake and seismic standards on almost all structures (apron, wall, foundation, base, column, spot, central, etc.)

The wedging in the opening or box realised at the bottom of the elevation is possible thanks to an injectable bag with a mineral grout of the CA M-TECH type or a resin presenting a compressive strength of + /- 100 N.

The implementation of the patent depends on the situation and must be prescribed by the builder or a firm of engineering consultants.

As described above, the patent refers to the very principle of para-seismic protection and the technical or conceptual adjustments according to the situation of a specific intervention.

The invention’s name is currently SISMOPLAQUE ®.

Measures to be taken on an existing building. According to the survey defining the need.
- After defining the ideal level for the detachment of the elevations in relation to the foundations, and laying out the area above the latter, thus allowing to keep the building mass clear.
- Creation of through boxes whose dimensions are defined by the congestion of the process.
- Setup of the Sismoplaques.
- Wedging with injectable bags.
- Horizontal sawing between each box.
- Repair by injecting flexible resin or a expansion joint foil.

Setting-up principle for a new building.

On low-rise construction with flowing groundwork:
- The setting-up of SISMOPLAQUE is to be done at the same level and time as the sealing membrane.

On an apron:
- Build ideally with a first horizontal levelled apron
- Place the Sismoplaques in sealing plates according to the thickness of the process.
- For the second slab and apply the usual treatment after stiffening.

Setting-up of the Sismoplaques with an existing building. Setting-up on a new construction.
The basic principle of the Sismoplaques is to separate premises fit for habitation from the transmission of seismic events inherent to the ground. Therefore, it is necessary to cut the building at foundation level, in theory under the building’s ground slab.

The recommended equipment must allow the horizontal sawing while avoiding vibrations.
This engine can be used when the surroundings and the location allow it

This equipment can be completed by a portable chainsaw.
The other solution is the intervention of a wall saw, which also exists on rails.
The intervention requires a survey of the pipes, cable penetration, draining, water system, etc.
It is desirable to take advantage of this type of intervention to set up a definitive sealing membrane or to inject flexible resin.