Tubular construction

The invention relates to a liquid flow channel flat bottom resting on a support surface flattened and tamped, and consisting of sections placed end to end and each formed by wall elements in juxtaposed concrete.

are already known, in particular for construction liquid flow conduits, for example networks sanitation, methods in which the duct consists of sections placed end to end formed each of precast concrete elements that build the each other by their longitudinal edges. Generally, such devices are provided for cross-sections of not more than 1 to 2 m².

However, the applicant has already proposed a new Construction system for realizing ducts having a much larger cross-section, may exceed 100 m² and therefore usable for the construction of underground passages for the circulation vehicles, the diverting a river in a embankment etc.

Such duct consists of tubular sections abutted each comprising at least one element to remove substantially planar placed on the ground or cast in place, two side elements positioned on either side of the slab and, in the case of a buried pipe, an arch element resting on the upper ends side elements so as to close the conduit.Chaque side member comprises a curved wall orientation generally vertical and which connects tangentially, upwardly with the arch element and towards the bottom, horizontally, with the raft element so as to constitute a smooth wall whose curvature varies continuously .

Furthermore, according to the characteristics essential for the European application 00 81 402, both side elements are each provided with stabilizing members which in the embodiment described in the patent, are constituted by section substantially pads triangular, distributed at the base of the element of side, each pad leaving a flat support face that allows the side element to stand alone without scaffolding. In this way, during the construction of a section of the structure, is firstly laying a raft element in the extension of the part already constructed and the two side elements, on either side of the raft, and finally the roof element resting on the two elements of side.

In the embodiment previously known, the side elements are connected at their base with the elements to strike by concreted seals which are genuine clavages, ensuring the fastening of the assembly. To this end, the lower edges of the side elements and the longitudinal edges of the apron are provided with reinforcements exceeding pending and, laying of the side elements, leaves between the longitudinal edges vis-a-vis a space wherein intersect these frames which are then embedded in a cast sealing mortar in place.

the so, the load applied to the element of vault and transmitted to the side elements can be resumed through the bottom and is therefore distributed over a large area. Thus a considerable improvement in the distribution of the stresses generated in the soil.

This securing of the apron with the basis of side elements also allows, for the latter, not not deviate outwardly opening under the weight of the vault element when it arises. It is Therefore, it is preferable to make the joints concreted before applying the vault elements. However, achieving joints may delay construction of the duct It is not until the concrete before laying the arch component.

In addition, in some cases, the two elements of side are not connected to one another by a slab, the latter being cast in place thereafter.

According to the invention, the liquid flow channel, consisting of sections put end to end and resting on a laying surface (61) leveled and compacted, each section being formed from elements prefabricated wall juxtaposed concrete and comprising two side elements (2,2 ') with a curved side wall inwardly and each bearing on the laying surface (61) by via a stabilization member (7) in flat bottom allowing the side element to stand straight without scaffolding, and a raft element bearing on the side elements, wherein each side element (2,2 ') is provided at its base with a widened sole (7) comprising two wings (71, 72) extending horizontally in hand console side of the side wall (20) the element (2,2 '), the latter comprising a lower part (26) substantially vertical, perpendicular to said sole (7) and extended upwards by a portion upper (21) curved inwards, the two wings (71, 72) of the widened sole (7) extending, respectively on widths (a1) inwardly and (a2) outwardly, the width (a2) being determined so that said side elements (2, 2 ') withstand by themselves to the water thrust exerted on the side walls (20).

In a particular embodiment, the two side elements and the raft element are provided, respectively, along their longitudinal edges vis-a-vis thinned ends in the form of short brackets having, respectively, inverted profiles leaving the faces inclined longitudinal bearing the same non-zero angle, not by law relative to the vertical and to the laying of the elements, the distance between the inside edges of the two side elements is less than the width of the raft element so that the short brackets in vis-a-vis mutually overlap and that their inclined bearing faces apply in pairs on one another, the short brackets formed the along the inner edges of the side elements pass over corbel longitudinal edges of the raft element said brackets having a profile and specific mechanical characteristics of to enable them to transmit to the raft element subject to the weight of water at least a portion of element reversal efforts next to.

The invention will be better understood from the description Next to these various embodiments given by way of example and represented in the accompanying drawings .

Fig.1 shows schematically in perspective a channel according to the invention.

In Figure 1, there is shown a mode of embodiment channel circulation liquid and in particular channels irrigation can have a very large cross-section .

Such a channel is formed of sections placed end to end and each comprising a 1 raft element to flat bottom resting on the two elements side 2. The upper 21 of the curved side wall 20 of each element side 2 is connected to a lower portion 26 consists of a vertical wall element centered on a support base 7 which constitutes the basic element 2 to face plane bottom 70 and includes two wings 71, 72, extending symmetrically inwardly and towards outside, on both sides of the vertical lower portion 26 of the wall 20, respectively over distances a1 and a2 from the center plane of the wall 26, each element 2 side is provided at its base with a widened sole 7 comprising two wings 71, 72 extending horizontally from either side of the vertical side wall 26.

The distance a1 is determined as a function of the height h of the element 2 and of the curved shape to inside so as to prevent reversal to inside the side member 2 when the latter is placed on the mounting surface 61.

A2 width of the outer flange 72 is determined so as to prevent the reversal outwardly the side member 2. The channel thus formed, which can be used for circulating water or other liquid 14 can either be open upwards or be covered a curved member 36 that, not having to bear embankment , Is made of a lightweight, eg a corrugated plastics material so as to have a certain stiffness. Such coverage protects 36 transported water against pollution and reduces evaporation risks especially if the plastic material is opaque.

Moreover, these risks are also reduced by the curved shape inwardly of the side elements 2 which in equal volume transported, reduces the free surface of the liquid 14.

Note that, in this case, the two side elements affect the soil a corresponding simply pushed their own weight and which is distributed over the entire surface bottom 70 of the sole 7. On the other hand, the conduit is normally placed in a trench but in a easy installation to achieve good soil. The risk of vertical thrust on the raft 1 under the effect of the water table is lowered and the strike is subject primarily the responsibility of the water transported 14.

The use of bearing pads 7 extended to outside allows two side elements to resist the pressure of the water acting on the side walls 20 which, in this case, are not interconnected by an element Arch.

The thrust of the water on the internal wings 71 also improves the stability and, in the case where using longitudinal joints applied to short brackets one on the other, determines a compression of the seal 45 which promotes sealing.

In this case, each end 4 of an element of 2 side is thinned obliquely to form a short console of substantially triangular section leaving one face longitudinal 41 inclined at an angle A nonzero and not right over vertically.

Each end of the raft 5 2 is thinned from the Similarly in reverse and therefore has a face longitudinal 51 inclined by the same angle A with respect to the vertical. The brackets 4 and 5 are therefore profiles inverted and can overlap mutually in the laying elements.

A seal 45 in the form of thin strip continues is interposed, if necessary, between the faces 41 and 51 inclined so as to seal the led both outward than inward. 5 formed consoles along the longitudinal edges of the apron 1 cover the consoles 4 forming the inner edges of the sole 7 of the side elements 2. These resistant therefore the reversal effects outwardly under the push water 14 on the one hand thanks to the 72 portions flange 7 projecting outwardly and covered by the R embankment, and also thanks to the blocking effect of 1 raft subjected himself to the weight of transported water. We Note, however, that the curved inward 2 side elements also promotes stability reducing the value of the horizontal force of thrust liquids.