Anchorage system using an anisotropic coupling inserted into the foundation studs

Abstract

 System of anchorage by means of anisotropic resistance coupling into foundation studs which improves the performance of the anchored element given the impact of a vehicle.
The main goal of the use of this completely new system of anchorage is to control the lamppost stiffness given the impact of a vehicle. This is achieved by inserting an anisotropic resistance coupling (C) into the foundation studs (B), because its geometry allows it to resist the stresses generated during its usual working, which are mainly of traction-compression, but it allows the shearing of its two parts, controlled by a mechanical fuse (D) which limits its resistance given the impact of a vehicle.
This coupling (C) must be placed in an area of the foundation which has been created with little hardness concrete, so that its breaking is not an impediment to the right working of the system.
It has application in the public works sector.

Description

b) DOMAIN OF THE TECHNIQUE:

[0001] It has application in the construction industry.

c) STATE OF THE PREVIOUS TECHINIQUE:

[0002] Nowadays, the anchorage system is done by means of continuous studs which are inserted into the foundation and joined to the base with screws. The diameter of these studs may be variable, although it is usually of 20 or 22 mm, which gives it extreme stiffness, given the impact of a vehicle, provoking strong decelerations on it which lead to serious injuries or even the death of the occupants of the vehicle.

d) EXPLANATION OF THE INVENTION:

[0003] The present invention, as its own title states, makes reference to a completely new system of anchorage for lampposts and other elements of the urban furniture. The main objective of this invention is to create a system of anchorage with the necessary resistance under current regulations to hold the lamppost or the element, but it must also have a controlled resistance given the impact of a vehicle.

[0004] This is achieved by means of the inset of an anisotropic resistance coupling into the foundation studs, as it can be seen in the picture. This is a valid solution because there is a basic difference between the stresses during the life of the lamppost and the stresses generated by the impact of a vehicle:

During its normal use, a lamppost mainly undergoes the wind stresses and the weight of the own lamppost. These stresses will generate on the system of anchorage sharp stresses of little value and flector moments which will cause traction-compression stresses in the foundation studs.

When the impact of a vehicle against the lamppost takes place, the main stresses generated are horizontal therefore, regarding the layout of the studs, they are of sharp type.

[0005] Taking all this into account, the coupling that has been designed presents a high resistance in case of traction-compression stresses, because it causes the overlap of geometries in a large area, and its dimensions have been designed so that it can support the stresses with some little deformations. When a horizontal stress on the lamppost, sharp on the couplings, takes place, taking into account their geometry, the two parts of the coupling can split up because the upper part of the coupling is stiffly joined to the upper stud and the lower part is joined to the other stud. Thus, the stress applied by the vehicle is transmitted to the upper part of the coupling, which will split up from the lower part because it is stiffly joined to the foundation. Thanks to its geometry in the shape of "C", and thanks to the fact that this movement is not completely guided , it allows that this type of coupling works properly in three directions, whereas there is one where there cannot be any separation between the two parts. Therefore, this direction must correspond with the direction of the vehicle which impacts from the exterior of the lane to the roadway because this is the direction that presents less possibility of accident.

[0006] It has been previously mentioned the controlled stiffness of the coupling, given an impact of a vehicle. This control is achived by means of the use of a mechanical fuse which joins both parts, as it can be seen in figure 2. The dimension and position of this mechanical fuse can be calculated in such a way that when the impact of a vehicle against the support takes place, the mechanical fuse breaks by shear in the joint of both parts. By varying the diameter and/or the material of the mechanical fuse the stiffness of the coupling can be controlled, getting the anchorage of the lamppost not to yield in case of an impact at low speed, but getting it to do it when the impact is at high speed, avoiding the danger that involves their excessive stiffness nowadays.

e) BRIEF DESCRIPTION OF THE CONTENT OF THE PICTURE:

[0007] The pictures included in the present report try, on the one hand, to show in a graphic way how these couplings must be placed in the system of anchorage and, on the other hand, to give an idea about how the geometry of this anisotropic stiffness coupling must be.

[0008] Figure 1 shows an overview of the system of anchorage. In this figure it can be seen how a coupling must he assembled over each foundation stud and how it is necessary to do the foundation in two parts, one with little hardness concrete and the other with plain concrete. Each of the letters of reference in the picture show the following:

A.- lamppost base.

B.- foundation studs.

C.- anisotropic coupling.

D.- inserted mechanical fuse.

E.- foundation die.

F.- little hardness concrete.

G.- plain concrete.
Figure 2 shows an idea about how this coupling can be made in order to get its suitable performance. Each of the letters of reference in the picture show the following:

H.- upper piece.

I.- lower piece.

J.- upper stud.

K.- lower stud.

L.- drill for the laying of the mechanical fuse.

M.- mechanical fuse.

Claims

1. "SYSTEM OF ANCHORAGE BY MEANS OF ANISOTROPIC RESISTANCE COUPLING INTO FOUNDATION STUDS" which improves the performance of the anchored element given the impact of a vehicle. The system is characterized by the insertion into the foundation studs of an anisotropic resistence coupling, due to the fact that its geometry allows it to resist the stresses generated during its usual working, which are of traction-compression mainly; but it allows the shearing of its two parts.

2. "SYSTEM OF ANCHORAGE BY MEANS OF ANISOTROPIC RESISTANCE COUPLING INTO FOUNDATION STUDS", according to demand number 1, characterized because the use of this system of anchorage and the insertion of the "mechanical fuse" with a calculated diameter, as it is shown in the pictures, allows to control the necessary force for the breaking of the coupling and, therefore, the severity of the bump before the breaking of this system of anchorage.

3. "SYSTEM OF ANCHORAGE BY MEANS OF ANISOTROPIC RESISTANCE COUPLING INTO FOUNDATION STUDS", as it is described in the body of this report and demands, which consists of 4 pages written only on one side and two figures.

Drawing