EP3310973A1

EP3310973A1 - Construction of the prefabricated column and beam type

Info

Publication number: EP3310973A1
Application number: EP16728392.8A
Authority: EP
Inventors: Libère Nitunga
Original assignee: Individual
Current assignee: Individual
Priority date: 2015-05-28
Filing date: 2016-05-25
Publication date: 2018-04-25
Anticipated expiration: 2036-05-25
Also published as: CN108138481B; JP2018520285A; EA034805B1; KR20180012809A; PE20171773A1; EA201700596A1; TN2017000477A1; US20180163389A1; US10494807B2; AU2016268484A1; BR112017025348A2; ZA201800002B; WO2016189476A1; MX2017014935A; EP3310973B1; CN108138481A

Abstract

The invention relates to a construction system for high-level prefabrication of building structures of the column and beam type, such prefabrication enabling this type of construction to be industrialized. The main development that makes it possible to achieve this objective under the same, if not better, technical conditions as with the conventional system is the large-scale use of vertical and horizontal braces. Such a construction system is of particular benefit in areas of high seismic risk, since the building is very light, made up of a set of structurally self-supporting units, highly triangulated and thus not easily deformed, all at a relatively low cost.

Description

Construction type columns and prefabricated beams

Description

Technical area

The present invention relates to the construction of buildings type posts and prefabricated beams, whether wood, reinforced concrete or any other material.

Prior art

Reinforced concrete buildings of the post and beam type are rather rare, because it is more advantageous to create horizontal and vertical connections, in one piece for each floor, as far as possible: reinforcement and pouring of the concrete. In the context of timber construction, however, posts and beams are widely used. They are always prefabricated and brought to construction sites to be assembled using various points and / or fittings.

Presentation of the invention

The present invention relates to a construction technique of wood, reinforced concrete or any other material, which consists of using prefabricated columns and beams in the factory, and to carry out their connection on construction site, on the one hand by a system of vertical and horizontal bracing, and on the other hand by a reinforced concrete junction at their intersection.

A central role is played by the bracings that securely hold the posts and beams in their final position as soon as their installation is complete. They make a link that we call here device, as opposed to the central link made at the intersection of said posts and beams.

Threaded rods are the most appropriate means of joining braces to studs and beams.

The central junction, can itself be cast on site; we are talking about partial or prefabricated prefabrication, and we are talking about total prefabrication.

The contact surface between a brace and a post or beam can be simple without any particular provision. In this case, if there is a force that tends to open or close the angle formed by the post and the beam, the bracing will play its role in opposing it. But for the bracing does not slip along the pole or beam, the assembly rod will be stressed in shear and should therefore be of large section. To remedy this problem, it is expected roughness on said surfaces, a notch in the post or beam, a notch into which enters a shim provided at the end of the brace, etc.. Such a system prevents any risk of sliding of the brace against the pole or against the beam in case of force tending to modify the angle formed by the post and the beam. The outer notch prevents closure of said angle, and the inner notch prevents its opening. For greater efficiency, the inner notch is longer than the outer notch, and may even form an acute angle with the axis of the pole or beam.

To prevent, reduce or eliminate the possible gaps between the prefabricated elements, namely the posts, the beams, the braces and the terminal blocks, but also to make a certain junction between said elements, is applied at their intersection a joint under form of cement mortar for example.

There is no limitation in the number or inclination of bracing pieces, nor in the number or type of their attachment to posts or beams: bolts, dowels, rivets, nails, etc. It is the same for the connection between the terminal blocks and the ends of the columns and beams described below.

Case of partial prefabrication: pouring of the junction on site

The beams are prefabricated at the factory, with bars or irons waiting to enter the junctions.

For poles, it is expected at the base an area of about 20 cm which will be concreted on site at the time of their installation, with waiting irons. At the top of the posts, waiting irons of a sufficient length to be part of the junction, and to serve as waiting irons for the subsequent assembly of the post of the upper stage.

Posts and beams are securely held in their final position by horizontal and vertical bracing. The ends of said posts and beams form a formwork lost at the time of pouring concrete in the junction.

At the time of laying the beams for attachment to the braces, it is useful to fix in the first place removable intermediate supports on the side and top of the poles, on which the beams will rest, which facilitates the adjustment and fixing the braces.

Insofar as the junction whose concrete is poured on site occupies a small area, it is possible to use a very high proportion of the concrete, to use the weld of the reinforcement in the connection instead of the usual overlap by juxtaposition. waiting irons, etc.

In a knot of construction intersect the many waiting irons of the post and adjacent beams. Their positioning may be a problem at the moment of construction due to their high rigidity and the small size of the space they occupy. To remedy this, the reinforcement of the junction is prefabricated, either completely or partially. It can take the form of a metal frame, preferably welded.

The columns and beams whose reinforcement entering the junction is prefabricated are provided with small pieces of iron waiting on which will be welded the prefabricated reinforcement of the junction.

Case of total prefabrication: prefabricated terminal blocks

Here is manufactured in factory, for each node, a complete junction block with as many branches as there are poles and beams in this node. The branches of said terminal block will be connected to the ends of the posts and beams that enter the node. The assembly area of a branch of the block with a post or a beam can be cut along an oblique line, ie bevelled, along a straight line, along a broken line, that is to say a staircase, etc. .

The junction blocks, as well as the ends of the posts and beams that form the junction are manufactured to ensure high mechanical strength: dense reinforcement and maximum concrete dosage.

The contact surfaces have deep grooves or other forms of asperities intended to prevent the relative movement of the elements to be connected. Threaded rods are the means of assembling poles and beams to the most suitable terminal blocks.

It is also possible to improve the connection between these elements by increasing their contact surface, on the one hand in the longitudinal direction to the posts and the beams by an increase in the length of the branches of the prefabricated terminal block, and on the other hand in the orthogonal direction to the columns and beams by increasing the width of said branches. In the latter case, it is as if the prefabricated terminal block had been cut out of a building, cutting not only the posts and beams, but also the corners of the walls and adjacent floors.

The ends of the columns and beams that enter this node then take the form of a T to match the dimensions of the terminal block thus formed. The thickness of the different parts of the terminal block must take into account the thickness of the ends of the columns and beams to which it will be connected, so that the total thickness does not differ too much from the thickness of the columns and beams, for example. example 20 cm. Thus, the central portion of the terminal block, which is not contiguous to any post or beam end, retains the thickness of the posts and beams, 20 cm in our example.

The areas of the terminal block to which are joined a single end of post or beam have a thickness of about 10 cm in our example, half the thickness of the structure of the construction. It is the same, mutatis mutandis, areas of the terminal block which are crossed by two ends.

It goes without saying that the thickness of one end of a post or beam must in turn take into account the thickness of the other ends and the branch of the terminal block with which they are going to be in contact. the knot, to make a total thickness of 20 cm in our example.

Wooden construction case

Usually, the assembly of posts and beams is usually done using various hardware. But in the context of the present invention, the junction is reinforced concrete. It is then a question of securely fixing the steel bars at the ends of the posts and the beams, so that they present waiting irons which will participate in the realization of said junction.

The present invention also takes advantage of cross-nailing for good attachment of wood bracing, poles and beams also wood. The areas that are likely to crack or burst as a result of intensive nailing are surrounded by compression fittings, which at the same time increases the pressure exerted on the nails used and improves the connection achieved.

Brief description of the drawings

Figure 1/20 shows the sectional view of the foundation and the lower chaining (2) of the building under construction.

We distinguish the foundation of the building (1), the lower chaining (2), and the iron waiting for the installation of a post of the first level or ground floor (3).

Figure 2/20 shows a sectional view of the installation of a post in the case of partial prefabrication.

The prefabricated zone is distinguished from the post to be laid (4), the standoff bars in the area of the post-concreting post (5). Figure 3/20 shows the pole at the time of its installation on the lower chaining. There are stand-off irons of the foundation or of the lower floor and of the post (5), the braces (6), as well as the connecting rods for the connection of the braces with the posts and the beams (7) .

Figure 4/20 shows a pole whose junction with the lower chaining is already concreted: the connection is complete.

Figure 5/20 shows the installation of the beams that will form the upper chaining of the stage.

A beam (8) is distinguished, as well as the reinforcement of the junction (9) constituted by the waiting bars of the left beam, those of the right beam and those of the upper end of the pole.

Figure 6/20 shows the same elements as the previous figure, but after concreting the junction: the completion of the junction is complete.

Figure 7/20 shows a sectional view of all the links in a node of the construction, highlighting the concreted parts on site.

Figure 8/20 shows a prefabricated terminal block for the connection of the various posts and beams that enter the node, in case of total prefabrication.

There are two branches for connecting two posts, and two branches for the connection of two beams, and holes (10) waiting for the passage of the connecting rods.

Figure 9/20 shows a terminal block that is already attached to the pole. There is an assembly rod (1 1), and two beams (1 2) pending fixation on the block.

Figure 10/20 shows an enlarged terminal block. Areas of the enlarged terminal block are distinguished at the corners of the walls and adjacent floors (13).

Figure 1 1/20 shows an enlarged terminal block which is already attached to the post. There are three assembly rods (1 1), and two beams (12) pending fixation on the block.

Figure 12/20 shows the diagram of an assembly of a beam with bracing. No special provision has been made for the contact area. In case of force tending to open or close the angle formed by the post and the beam, the bracing will oppose it. The connecting rod will be stressed in shear and must be dimensioned.

FIG. 13/20 shows the diagram of the same beam-bracing assembly in which a notch in which a wedge fits in the beam is provided. provided on the bracing, to prevent sliding of the brace against the beam, and shear forces that would result for the connecting rod.

Figure 14/20 shows the schematic of the same beam-bracing assembly in which the internal bracing blockage notch is deeper than the outer notch.

Figure 15/20 shows the diagram of the same beam-bracing assembly in which the notch provided in the post or the beam is less than 90 °.

Figure 16/20 shows a sectional view of a typical junction of the construction. We distinguish the pole (4), a beam (8), a bracing (6), and the reinforcement of the junction (9).

Figure 17/20 shows a sectional view of a reinforcement of the prefabricated junction. We distinguish the reinforcement of the prefabricated junction (14).

Figure 18/20 shows a sectional view of a typical construction node, prior to the installation of prefabricated reinforcement.

We distinguish the pole (4), a beam (8), and the removable intermediate support (15). Figure 19/20 shows in detail the end of a beam when using a prefabricated reinforcement.

We distinguish the beam (8), as well as the ends of horseshoes on which will be welded the prefabricated reinforcement (16).

Figure 20/20 shows the assembly of prefabricated reinforcement on the beams.

There is a beam (8), and prefabricated reinforcement (14).

Best way to realize the invention

The best way to achieve the invention is described below: 1 ° Factory manufacturing of all poles, beams and braces.

On the beams are provided pieces of iron waiting about 4 cm in length, on which will be welded the reinforcement of junctions also prefabricated (Fig.19 / 20). By cons the poles will be provided with waiting irons about 20 cm long at the base, and waiting irons of about 40 cm at the top (Fig 2/20). 2 ° Construction of a classical foundation for a reinforced concrete construction.

Waiting irons are planned for future poles (Fig. 1/20).

3 ° Poles of the first level of construction. The waiting irons of their base intersect with the waiting irons provided in the foundation. The columns are held in vertical position by the braces connecting the said posts to the lower chain (Fig. 3/20). Horizontal bracing connecting the beams constituting the lower chaining, adjacent to each post is fixed. After checking the verticality of the columns, we proceed to the formwork and concreting of this part of the posts. Insofar as the posts are firmly held in their final positions by the bracing system, the construction work can continue shortly after pouring the concrete in the junctions, or even before said pouring. 4 ° Laying beams which will form the upper chaining of the floor.

To do this, we first fix removable supports laterally on the upper part of the columns, then the beams, then the braces (Fig. 18/20). After fixing the vertical and horizontal braces, the removable supports are removed and construction work can continue. 5 ° Fixing of the reinforcement of the prefabricated junctions.

Prefabricated reinforcements are welded to the standpipes of columns and beams (Fig. 20/20). The formwork is then made where it is necessary, that is to say in the nodes which comprise two or three beams, keeping in mind that the ends of the columns and beams constitute a lost formwork, then the concrete is poured. in the junction.

6 ° The slab is made, then step 3 ° is repeated for the continuation of the construction of the next stage.

It should be noted that it is possible to pour the concrete in the joints once and for all, at the end of the construction work of the whole structure. Possibilities of industrial application

The primary object of the invention is as much prefabrication as possible of the structure of buildings of the type of columns and beams, prefabrication which allows industrialization of this type of construction. The main development that achieves this goal under the same technical conditions, or better than in the conventional system, is the massive use of bracing both vertically and horizontally. They constitute a peripheral and solid junction which connects the posts and the beams on the one hand and the beams between them on the other hand. The central junction, which takes place at the intersection of posts and beams can be done on site or prefabricated, and therefore industrialized, or at least highly standardized.

Whether in the case of on-site junctions or in the case of prefabricated junction blocks, everything is practically done in the factory, with the resulting advantages: standardization of the manufacturing, quality and speed of execution, reduction costs and construction times.

In addition, the weight of the building will be reduced, because for the same resistance to vertical and horizontal loads, this modular lattice structure is lighter than a conventional structure. The main constraint of the system is that the braces occupy the axis of the walls for greater efficiency, which prevents or reduces the use of the usual materials in the construction of walls such as bricks and blocks of all kinds. But this will push manufacturers to adopt more often the walls and walls adapted to this type of structure, for example the panels currently used in the construction of wood.

Finally this constraint will be largely offset by the many additional benefits that will result from the use of lightweight walls and walls, to such an extent that one could even speak of a multiplier effect in terms of weight reduction, cost and efficiency. deadlines for completion of the construction.

Such a construction system is of special interest for regions with high seismic risk, because the building is light, consisting of a set of structurally self-sufficient units, strongly triangulated and therefore very little deformable, all at a relatively modest cost .

Claims

claims

1. A type of construction technique such as prefabricated poles and beams made of wood, reinforced concrete or any other material, characterized by a systematic and modular prefabrication of columns and beams, their connection taking place on the construction site of a building. part by a system of vertical and horizontal bracing, and secondly by a reinforced concrete junction at their intersection, the lower end of the posts being concreted on site to ensure their connection with the nodes on which they rely because these were manufactured at the time of construction of the foundation or the lower floor.

2. A construction technique according to the preceding claim, wherein the junction is not made on site, but prefabricated in the factory in the form of junction block which will be connected to the ends of poles and beams.

3. A building system according to the preceding claim, wherein the prefabricated terminal block is widened to the corners of the walls and adjacent floors, the pole ends and beams attached thereto being enlarged accordingly.

4. A building system according to the first claim, wherein the reinforcement of a joint is precast separately from the posts and beams and takes the form of a welded metal frame, which prefabricated reinforcement will be welded to the ends of the reinforcement of the posts and / or beams on construction site.

5. A building system according to the first or the fourth claim, wherein removable intermediate supports are placed laterally on the upper part of the columns, and on which the beams will rest before or during fixing braces.

6. A building system according to any one of the preceding claims, characterized by the use of joints, for example in the form of cement mortar, to prevent, reduce or eliminate the possible play between the different prefabricated building elements, and also for to achieve a certain connection between the said elements.

7. A building system according to any one of the preceding claims, characterized in that the posts, beams and braces are provided with anti-slip devices, such as notches, wedges and lugs.

8. A technique according to any one of the preceding claims in the context of the wooden construction, characterized by the installation of brackets in areas where an element may be subject to cracking or bursting after intensive nailing.