EP4752314A1

EP4752314A1 - Structural connection

Info

Publication number: EP4752314A1
Application number: EP24461638.9A
Authority: EP
Inventors: Krzysztof Kacalinski; Slawomir Samonek
Original assignee: Pelter Sp Z OO
Current assignee: Pelter Sp Z OO
Priority date: 2024-11-27
Filing date: 2024-11-27
Publication date: 2026-06-03

Abstract

The subject of the invention is an airtight connection of an element made of a first material with a second element made of a second material, wherein the second material is different than the first material, and the first element comprises a first part, which constitutes a bare end, extending from the second part, and the second element comprises a socket part on at least one of its ends, characterised in that the second element (B), in the socket part, has an outer flange (C) and an inner flange (D), and the first part (A1) of the first element (A) is connected by means of anchors (GW) with the inner flange (D) of the socket, and the second part (A2) of the first element (A) is connected by means of anchors (GZ) with the outer flange (C), wherein sealing layers (E) are located between the first part (A1) and the outer flange (C) and between the second part (A2) and the inner flange (D). The invention also relates to a method of constructing a shelter using the above connection, a shelter module, and a modular shelter.

Description

The subject of the invention is an airtight mechanical structural connection of elements made of different materials, a modular shelter module, a method of connecting modules, and a modular shelter.
Shelters made of connected modules are known in the state of the art. American Patent Application US2013091783A1 describes a shelter comprising an inner front module having an airlock and an outer front module which is slidingly attached to the inner front module. The shelter has an inner rear module and an outer rear module which is slidingly attached to the inner rear module. When the outer front module and the inner front module are in the extended state, and the outer rear module and the inner rear module are in the extended state, and the outer front module and outer rear module are attached, they form an airtight chamber in which users are protected from the external environment. In turn, from International Application WO18186771A1 , a structure and a modular element for a subsurface structure intended for short-term accommodation of humans underground are known. The underground module (structure) comprises a cylindrical, vertically mounted housing, the bottom part of which is connected to a base, and the top part of which is connected to a cover having a door aperture, wherein the housing is comprised of multi-layered sections interconnected by tongue-and-groove type joints, each section consisting of an outer shell and an inner shell with a layer of heat-insulating material therebetween. The modular element comprises a cylindrical housing consisting of four interconnected segments, the bases of which have flanges formed along their edges. The flanges are provided with working apertures for fastening elements. Several rows of reinforcing ribs are formed on the inner side of each segment. A joining assembly of the double tongue-and-groove type is formed between the segments, providing rapid assembly as well as enhanced waterproof properties of the modular element once assembled.
The technical problem is providing a connection between two different structural materials, particularly concrete and plastic, which would be characterised by high airtightness, uniform adhesion of the connected materials with respect to each other and high precision of connection as well as high mechanical strength. Another problem is providing a shelter module and/or a modular shelter having airtight connections between module elements and/or modules. In addition, it should be possible to connect the elements of the shelter before its installation at the target site as well as at the installation site (e.g. in an excavation pit).
The first object of the invention is an airtight connection of an element made of a first material with a second element made of a second material, wherein the second material is different than the first material, and the first element comprises a first part, which constitutes a bare end, extending from the second part, and the second element comprises a socket part on at least one of its ends, characterised in that the second element, in the socket part, has an outer flange and an inner flange, and the first part of the first element is connected by means of anchors with the inner flange of the socket, and the second part of the first element is connected by means of anchors with the outer flange, wherein sealing layers are located between the first part and the outer flange and between the second part and the inner flange, wherein the anchors are arranged in mounting hole arrangements in the first element and in the second element, preferably, the first element is made of concrete mass and the second element (B) is made of plastic, preferably polyethylene, most preferably high density polyethylene, preferably, the second element (B) is in a form of a pipe.
In a preferred embodiment of the invention, the second part of the first element is a partition wall, or an emergency exit wall.
In another preferred embodiment of the invention, the first part of the first element is in a form of a ring, having an inner diameter and an outer diameter.
In yet another preferred embodiment of the invention, the mounting hole arrangement in the outer flange of the second element corresponds to the hole arrangement in the second part of the first element.
In another preferred embodiment of the invention, the hole arrangement in the first part of the first element corresponds to the mounting hole arrangement in the inner flange of the second element.
In yet another preferred embodiment of the invention, the inner dimension of the socket in the element corresponds to the outer diameter of the first part of the first element.
In yet another preferred embodiment of the invention, the inner flange is located in the socket of the second element at a distance from the end of the second element corresponding to the length of the first part of the first element.
In yet another preferred embodiment of the invention, the anchors are chemical anchors.
In another preferred embodiment of the invention, the sealing layers are sealings that swell in contact with water.
In another, different, preferred embodiment of the invention, the first element is fixed in relation to the second element, connected by means of anchors using a bolted joint.
The second object of the invention is a shelter module, characterised in that it is comprised of at least one first element made of a first material connected to at least one second element made of a second material, wherein the second material is different than the first material, and the second element is connected by its first end to the at least one first element using the connection according to the first object of the invention,

wherein the first element is made of concrete mass,
wherein the second element is made of plastic, preferably polyethylene, most preferably high density polyethylene,
optionally, the second element is connected at its ends to two first elements.

The third object of the invention is a method of constructing a shelter comprising provision of at least one first element, at least one second element, characterised in that the second element is connected by its first end to the second element using the connection according to the first object of the invention, and the second end of the second element is connected to another first element, optionally, the second end of the element is connected to the first end of another element until a desired length of the connected elements is achieved, and the end of the connected elements is connected to the first element.
In a preferred embodiment of the invention, the first element is connected to the second element before fixing the shelter module at the target site or after fixing the shelter module at the target site.
Another object of the invention is a modular shelter, characterised in that it is constructed of at least one module or modules according to the second object of the invention, or is constructed using the method according to the third object of the invention.
In a preferred embodiment, the shelter is constructed of modules connected by the ends of the second elements, optionally, the second elements are connected to each other by their first and second ends, forming a continuous structure, wherein at the first and second end of the continuous structure, the second elements are connected to the first element using the connection according to the first object of the invention.
The connection according to the invention of the elements made of different materials (concrete/plastic), using a socket connection mechanically assisted by anchors, washers and nuts arranged symmetrically, provides uniform adhesion of materials with respect to each other. Referring to the solutions in the state of the art, an improvement was made by mechanically connecting only three elements of the shelter: two partition walls A, made of concrete, and a polyethylene pipe B. In case of the above-mentioned solution described in WO18186771A1 , the elements forming the shelter were connected multiple times, which makes it difficult and time-consuming in construction site environment to achieve precise connection and maintain airtightness of the structure. The solution of joining partition walls with a ready-made polyethylene product according to the invention is characterised by connection strength, shear resistance and tightness of the structure during the onset and after the passage of an overpressure wave. The connection of these two elements is carried out efficiently at the shelter installation site using commonly available mechanical tools and a crane.
The embodiments of the invention are depicted in the drawing, wherein:

Fig. 1 shows the connection of element A, a concrete wall, with element B, a polyethylene pipe, a socket connection,
Fig. 2 shows in detail the arrangement of holes in flanges C and D, mounting positions of sealings E, mounting position of anchors,
Fig. 3 shows, from the right side, a top view of the socket connection of two elements A and B, and from the left side, a side view of the socket connection of two elements A and B,
Fig. 4a shows a three-dimensional view of a socket connection of elements A and B from the perspective of the concrete element A in the foreground,
Fig. 4b shows a three-dimensional view of a socket connection of elements A and B from the perspective of the polyethylene pipe element B,
Fig. 5 shows a three-dimensional view of the shelter module comprised of concrete elements A and A" and a polyethylene pipe B, and an evacuation shaft S made of a polyethylene pipe,
Fig. 6 shows a top view of the shelter module,
Fig. 7 shows a side view of the shelter module,
Fig. 8 shows a three-dimensional view of the shelter module comprised of concrete elements A and A", and elements forming section B-B" connected using an extrusion weld, and an evacuation shaft S made of a polyethylene pipe,
Fig. 9 shows a three-dimensional view of the shelter module comprised of concrete elements A and A", and elements forming section B-B'-B" connected using an extrusion weld, and an evacuation shaft S made of a polyethylene pipe.

Example 1. Mechanical connection of a large diameter polyethylene pipe with concrete structural elements

The connection of an element made of a first material with a second element made of a second material, which is different than the first material, according to the invention will be described below. The invention relates to a connection of an element A made of concrete, which may be a partition wall of the main entrance to the shelter or of the emergency exit having dimensions of 3200×3200×300 mm, with an element B made of HDPE plastic having an inner diameter of 3000 mm. The connection of the element A with the element B is a socket type connection.
In the following part of the description, in order to illustrate the object of the invention, a concrete partition wall having two main structural components was chosen as the element A (Fig. 1 and 2). The first component is a ring A1 made of concrete. It has an outer diameter of 2950 mm, an inner diameter of 2500 mm, and a length of 250 mm, the second component is a partition wall A2 having outer dimensions of 3300×3300 mm, thickness of 300 mm, and an opening intended for the entrance door to the shelter. The elements A1 and A2 are pre-assembled together and constitute a single cohesive structural element A. The ring A1 of the structural element A is the bare end in the socket connection. In case of other concrete structural elements, it is important for them to comprise the ring indicated above as A1. It is important, because the above-mentioned ring A1 corresponds to the bare end in the socket connection and is inserted into the socket of element B. Therefore, the ring A1 allows effective connection of elements connected in the socket type connection.
Inside and outside of the structural element B, two polyethylene flanges - the outer one C and the inner one D - are mounted by means of extrusion welding. These flanges are pre-mounted during the manufacture of pipe B. Before assembling the elements A and B, it is necessary to verify the perpendicularity of the flanges C and D in relation to pipe B, as well as the quality of the weld and connection. However, it is possible to mount them temporarily or correct the mounting at the installation site. In this case, one should be equipped with an extrusion welding kit, e.g. WLI 3000 type from Uponor. The outer flange C is located at the end of pipe B. The inner flange D is located close to the end of pipe B and is spaced from it by a distance equal to the depth of the socket, about 250 mm, which also corresponds to the length/thickness of the element A1 ring of the partition wall A.
In order to construct an airtight shelter, the concrete wall element A should be connected to the polyethylene pipe B (Fig. 1 and 2). The socket type connection is obtained by sliding the socket of the polyethylene pipe B onto the ring A1 of the partition wall A, the connection should be made in such a way that the outer flange C of pipe B engages with the surface of the concrete wall A2, while the inner flange D engages with the front of the ring of the concrete wall A1. It will be obvious for a person skilled in the art, from the following description, that the polyethylene pipe B can be connected at both ends with a concrete element in a manner described above, as will be presented in the description below. For the sake of clarity of the description of the invention, a connection on one side of the structural element B will be presented. The elements connected together: A - provided with a ring, in this case it is the bare end A1, and element B - the socket, are mounted to each other, forming a socket connection. Next, the elements A and B are connected to each other using the elements C, D, F, GW, GZ, H, I (Fig. 1 and 2). Elements A1 and A2 of the concrete wall A as well as the pipe B on the inner surface B1 thereof should be checked, verifying that elements A and B are free of any unevenness, cracks, grooves, etc. on the surfaces which adhere to each other after connecting the elements A and B. If damage is found, repairs must be made before continuing assembly. During assembly of elements A and B, it is possible to connect the element A to B as well as B to A, depending on the laid foundation of the objects at the installation site.
It is recommended to make holes F on the outer C and inner D flange of the polyethylene pipe and to make holes in the concrete wall A2 and the frontal plane of the concrete cylinder A1, and to install chemical anchors G therein before placing the element at the installation site in the excavation pit. This will facilitate making the holes and connecting elements A and B in the next step. It can also be conceived to make the above-mentioned holes at the installation site in the excavation pit.
In the element A2, 24 symmetrical holes F of the same depth and diameter are made. Next, in the element A1 on its frontal wall, also 24 holes F of the same diameter and depth are made. In the outer flange C and in the inner flange D of pipe B, a total of 48 holes F are made, 24 on each of flanges C and D. The holes in the flanges are indicated as CF - holes in the outer flange, DF - holes in the inner flange.
In the example above, pipe B having an inner diameter of 3000 mm has 48 holes F in total, 24 in flange C and 24 holes in flange D. Changing, i.e. increasing or decreasing, the diameter of the pipe may cause the number of holes F to increase or decrease.
It should be checked that all anchors GZ pass through the 24 holes CF in the outer flange C and that the anchors GW pass through the 24 holes DF in the inner flange D. Next, inside previously made holes A1F and A2F, in the elements A1 and A2 respectively, in the concrete wall A and on previously mounted anchors GW/GZ, washers H and nuts I will be installed. Elements A and B prepared in such a way are connected to each other by tightening the nuts according to the intended force for a given type of nuts. For example, an M33 nut class 8.8 is tightened using a force of 2161 Nm. All anchors GW/GZ used to connect the elements A and B are chemical anchors.
On the outer surface of the concrete wall A2, below the holes A1F for mounting anchors G, and on the front surface of the cylinder A1, a sealing E is mounted, e.g. bentonite waterstop sealing tape 20×25 mm (Fig. 2), which swells in contact with water and moisture. This provides airtight connection between two different materials, such as concrete and polyethylene. This solution can be used for sealing various types of spaces, rooms, pipelines which require connecting concrete elements with large diameter polyethylene pipes. The described solution may be used for constructing modular and singular composite shelters (single module) made of polyethylene and concrete.
Polyethylene pipe B may be made of high density polyethylene (HDPE) or a different type of polyethylene providing an adequate, i.e. comparable to HDPE, mechanical strength and chemical resistance. An example of polyethylene pipe B, meeting the requirements of the invention, is a pipe manufactured by GF Uponor (https://www.uponor.com/pl-pl/infra/produkty/kanalizacja-deszczowa/rury-weholite), a Weholite pipe SN 8; DN 3000; PE-100.

Example 2. Shelter constructed of a polyethylene pipe with concrete structural elements

The shelter constructed by connecting concrete structural elements in a form of a partition wall A and one end of element B in an airtight, hermetic manner, provides protection for people inside against threats related to chemical, biological and conventional weapons. This connection of elements A and B forms a shelter module. The second end of the element may be connected to the second end of the second element B, essentially similar or identical to the first element B, or to the concrete element A (Fig. 5, 6). Elements B may be connected to each other using an extrusion weld, for example by means of a WL 3000 type welding machine. Further elements B may be connected (welded), forming a shelter section of any length, e.g. two-element B-B" (Fig. 8) or longer B-B'-B", as shown in Fig. 9. A socket for connecting, using the method according to Example 1, with a concrete element, e.g. a partition wall A", is located at the end of the section of elements B. An emergency exit in a form of a shaft will be installed from the outside of the wall A".
In the concrete partition wall (A, A"), an explosion-proof door with increased strength and resistance to overpressure of 0.4 MPa is installed. Structure of the double-walled polyethylene pipe B provides resistance to impact of an overpressure wave of 0.1 MPa. The polyethylene pipe B is pre-fabricated and comprises a straight section having an inner diameter of 2600 or 3000 mm at the ends, and has two extrusion-welded flanges for connecting with concrete - the outer one C and the inner one D. An important feature of this solution, due to the lightness of the material used for manufacturing of the pipe, in this case PE 100 granulate, will be the ease of transporting the element B and connecting it with the concrete structural elements A in the excavation pit.
To verify the strength of the polyethylene pipe B with an internal diameter φ of 3000 mm used to construct the shelter, field tests were carried out, which confirmed its resistance to the load of a direct wave pressure generated as a result of an underground explosion with a value greater than 0.1 MPa. Another advantage of the presented structure made of pipe B is its structural resistance to the effects of physical forces such as static and dynamic soil pressure. Additionally, the PE100 polyethylene, of which the pipe is made, is resistant to corrosion, erosion and corrosive chemical substances. The use of concrete staircases, vestibules and partition walls ensures the safety of the shelter structure against external factors such as high temperatures, impacts of overpressure waves caused by an explosion, mechanical impacts, acts of sabotage and vandalism. The concrete element (concrete wall) A is equipped with an explosion-proof door enabling access to the interior of the shelter and providing effective protection against an overpressure wave of 0.4 MPa and other threats such as firearms fire, shrapnel impacts, etc. Connected to above-mentioned concrete elements and installed 1 to 3 metres below the surface of the ground, element B (polyethylene pipe) ensures an airtight, hermetic environment inside the shelter that is resistant to threats resulting from warfare, climatic or technical disasters.
The use of this solution will be beneficial in terms of ease of production, lower transport costs, and speed of assembly compared to shelters made entirely of concrete or steel.

List of reference indications:

A - concrete element
A" - second concrete element, e.g. a wall for connection with an evacuation shaft
A1 - concrete ring - bare end
A2 - concrete partition wall
B, B', B" - polyethylene pipe having an inner diameter of 2600 or 3000 mm, made of PE-100 plastic
B1 - inner surface of pipe B
C - outer flange
D - inner flange
E - sealing
F - hole
G - anchor
H- washer
I - nut
S - evacuation shaft
CF - holes F in the outer flange C
DF - holes F in the inner flange D
GZ - anchors of the outer connection
GW - anchors of the inner connection
A1F - holes in the concrete ring A1
A2F - holes in the wall A2

Claims

An airtight connection of an element made of a first material with a second element made of a second material, wherein the second material is different than the first material, and the first element comprises a first part, which constitutes a bare end, extending from the second part, and the second element comprises a socket part on at least one of its ends, characterised in that the second element (B), in the socket part, has an outer flange (C) and an inner flange (D), and the first part (A1) of the first element (A) is connected by means of anchors (GW) with the inner flange (D) of the socket, and the second part (A2) of the first element (A) is connected by means of anchors (GZ) with the outer flange (C), wherein sealing layers (E) are located between the first part (A1) and the outer flange (C) and between the second part (A2) and the inner flange (D),
wherein the anchors (GZ, GW) are arranged in mounting hole arrangements in the first element (A) and the second element (B),

preferably, the first element (A) is made of concrete mass and the second element (B) is made of plastic, preferably polyethylene, most preferably high density polyethylene, preferably, the second element (B) is in a form of a pipe.
The connection according to claim 1, characterised in that the second part (A2) of the first element (A) is a partition wall or an emergency exit wall.
The connection according to claim 1, characterised in that the first part (A1) of the first element (A) is in a form of a ring, having an inner diameter and an outer diameter.
The connection according to claim 1, characterised in that the mounting hole arrangement (CF) in the outer flange (C) of the second element (B) corresponds to the hole arrangement (A2F) in the second part (A2) of the first element (A).
The connection according to claim 1 or 4, characterised in that the mounting hole arrangement (DF) in the inner flange (D) of the second element (B) corresponds to the hole arrangement (A1F) in the first part (A1) of the first element (A).
The connection according to claim 1, characterised in that the inner dimension of the socket in the element (B) corresponds to the outer diameter of the first part (A1) of the first element (A).
The connection according to claim 1, characterised in that the inner flange (C) is located in the socket of the second element (B) at a distance from the end of the second element (B) corresponding to the length of the first part (A1) of the first element (A).
The connection according to claim 1, characterised in that anchors (GW, GZ) are chemical anchors.
The connection according to claim 1, characterised in that the sealing layers (E) are sealings that swell in contact with water.
The connection according to any of the preceding claims, characterised in that the first element (A) is fixed in relation to the second element (B), connected by means of anchors (GW, GZ) using a bolted joint.
A shelter module, characterised in that it is comprised of at least one first element (A) made of a first material connected to at least one second element (B) made of a second material, wherein the second material is different than the first material, and the second element (B) is connected by its first end to the at least one first element (A) using the connection according to claim 1,
wherein the first element (A) is made of concrete mass,

wherein the second element (B) is made of plastic, preferably polyethylene, most preferably high density polyethylene,

optionally, the second element (B) is connected at its ends to two first elements (A, A").
A method of constructing a shelter comprising provision of at least one first element, at least one second element, characterised in that the second element (B) is connected by its first end to the second element (A) using the connection according to claim 1, and the second end of the second element (B) is connected to another first element (A), optionally, the second end of the element (B) is connected to the first end of another element (B) until a desired length of the connected elements (B) is achieved, and the end of the connected elements (B) is connected to the first element (A).
The method of construction according to claim 12, characterised in that the first element (A) is connected to the second element (B) before fixing the shelter module at a target site or after fixing the shelter module at the target site.
A modular shelter characterised in that it is constructed of at least one module or modules according to claim 12, or constructed using the method according to claim 13.
The modular shelter according to claim 14, characterised in that it is constructed of modules connected by the ends of the second elements (B), optionally, the second elements (B) are connected to each other by their first and second ends, forming a continuous structure, wherein at the first and second end of the continuous structure, the second elements (B) are connected to the first element (A, A") using the connection according to claim 1.