FR3070172A1 - SPECIAL FOUNDATIONS BY WELL, ADAPTED TO PENTUS VOLCANIC SITES, FOR THE PURPOSE OF AVOIDING RIDING AND SLIPPING - Google Patents

Abstract

The invention relates to constructive details of foundations-basements, likely to oppose the main causes of major disasters suffered by the buildings of Reunion (and more generally tropical and equatorial volcanic sites.) During climate phenomena of the type : cyclones, and taking into account the steep terrain, the most prevalent in this type of sites. To know: Settlements and landslides. The characteristics of the building respecting this invention make it possible to solve the problems posed by future tropical cyclones, in their constraints due to precipitation, constraints which have worsened by 15% in the last decade. And it is the specific system of adaptation to soils drilled wells and piles linked to the compact substrate by a continuous reinforcement which allowed to find the reliable solutions to these primordial problems of settlements and landslides. But this is not limited to the utility of the innovation proposed for patenting. Indeed, the removal of the retaining walls that accompany the system of adaptation to the ground currently the most widespread: by cut-backfill, not only preserves the natural sites, but eliminates the multiplication of losses due to the poor execution current of these walls .

Description

Description of the subject of the patent:

The file concerns an innovative concept of foundations-bases answering the requirements and specificities of the island of Reunion, and tropical and equatorial volcanic sites in general.

Indeed, currently, the models of houses or the original plans proposed on the island. include continuous footings or wells estimated to be "on the right soil", this being not researched during the course of studies or construction.

These provisions do not take into account the natural specificities of Reunion. This results in the multiplication of excavation-embankment earthworks, therefore retaining walls, and many major disasters, especially during cyclones.

The concept of foundations-bases presented in this dossier responds first to the local natural conditions in terms of soils, which are of volcanic origin,

This specificity, which is in the form of a compact basalt base, on which a thin layer of more or less fine material has formed, causes difficulties in adapting to steep soils, but also major disasters caused by very heavy cyclonic precipitation, which generates subsidence and landslides under the effect of water infiltration in the upper soft layers, and generates destructive surface water flows.

The elements to be protected by this file therefore consist of a set of technical provisions intended to counter the effects of future cyclones on the foundations of buildings of all kinds:

They relate to a foundation system + bases, comprising:

Concrete wells drilled to find the ubiquitous surface of compact basalt from old lava flows, most of the time close to the surface on sloping ground. These wells are crossed by reinforcements deeply anchored in the basalt, and piles of large section of variable height, these reinforcements being extended as far as the connection pilings / beams for supporting floors, and beams / masonry floors.

The reinforcements plunge into the bedrock are continuous, even into the compression slab of the floors.

The following plans and attached drawings specify what the innovations to be protected consist of:

-Drawing 1 defines the compact substrate-well-pile-piles-beams-floor assembly, in elevation and in top view in the following three cases:

-Slope terrain and land less than 2.50m thick

-Flat ground -Thickness of land greater than 2.50m.

The industrialization of this set is allowed, first by its simple and repetitive constitution, then by the possible prefabrication of the following elements: Heads of piles and beams supports of floors.

The foundation-base set therefore includes:

A supporting slab which rests on a set of foundations plus foundations (2) which consists of:

Reinforced concrete drilled wells (3) down to the compact substrate, topped with reinforced concrete pilings (5), the heads of which receive the supporting beams (6) of the slabs. (6.1)

Of a vertical reinforcement (7) connecting: Load-bearing floors - beams - stilts - foundation wells natural seat foundation (7). It is continuous, and, starting from the compression slab of the floors, it penetrates deep into the compact rocky natural foundation. (1m minimum), thanks to drilling at the bottom of the well (4).

The base of the wells therefore rests on the incompressible compact substrate, as soon as it can be reached by an auger, or a mechanical shovel, and the reinforcement of these wells penetrates into the compact substrate.

If the thickness of loose soil is more than 2.50m, micro-piles penetrate at least 1m into the compact substrate, and are linked to the thin well that supports the pilings.

The innovation to be protected therefore resides in the following double condition: Foundation by wells lowered to the compact supporting substrate, and whose vertical reinforcement, continuous from the compression slab of the floor penetrates deeply into this substrate.

And this, whatever the nature, the section of the built parts, and the nature of the compact substrate.

The numbering refers to drawing 1, below

Claims (2)

1: Structure of buildings, in particular intended for individual houses or not, characterized in that it comprises: -A foundation system by drilled wells (drawing 1) resting on the compact substrate, and integral with this substrate by a continuous vertical reinforcement (7) 2: Building structure according to claim 1, characterized in that the base foundation system comprises: - Reinforced concrete drilled wells (3) down to the compact substrate (4) - Topped with reinforced concrete stilts (5), the heads of which are intended to receive: slab-bearing beams (6), - Slabs of slabs or solid reinforced concrete (6.1) - The vertical reinforcement (7) of the assembly being continuous from the compression slab, to the compact substrate into which it penetrates deeply. (1m mini)