WO2022259275A1

WO2022259275A1 - Dynamic modular anti-blast wall

Info

Publication number: WO2022259275A1
Application number: PCT/IT2022/050154
Authority: WO
Inventors: Massimo Perusi
Original assignee: Massimo Perusi
Priority date: 2021-06-07
Filing date: 2022-06-01
Publication date: 2022-12-15
Also published as: IT202100014699A1

Abstract

Modular wall for protection from attacks with bombs or blasting bullets that goes beyond the concept of a wall as an inert, compact and solid artifact, that contrasts forces and pressures caused by external explosions with a structure that leaves any individual element inside it free to move and that contrasts the explosions of bullets that succeed in entering its structure with the insertion in the wall of transversal hollow gun-barrel-bores shaped holes that carry the gases under pressure towards the outer edges of the wall, where an external container acts as a gun muzzle brake, diverting the gases and any bullets outward and using part of the pressure to compact the wall.

Description

DESCRIPTION of the invention entitled:

"Dynamic modular anti-blast wall" in the name of PERUSI Massimo, of Italian nationality.

Field of application This invention can be defined as a dynamic defence installation.

The construction sector (04), that of military devices, firearms (22), and defensive barriers (25) are the main areas of this invention but not the only ones; terminology and examples are taken from these areas, for illustrative and non-reductive purposes only. The terms anti-blast wall are used in different contexts to indicate contrast barriers to various types of possible explosions, from fuel deposits to sites where dangerous chemical compounds are used, etc.

Even if it may be adjusted to any of these situations, this invention is intended to propose a solution in the defensive field, meaning by blast the explosion caused by a bomb or by an explosive projectile; the aim of these explosions is to hit a solid and compact body, the wall, trying to break up its structure, to make it collapse, and to make it unusable, by creating three types of damage:

• damages from the physical impact of the bullet against the target · thermal damages caused by variations in temperatures

• and finally the greatest damage, that is the one caused by the shock wave or pressure wave, created by the blast of the explosive material contained in the device, which shakes the compact structures making them yield in their weakest points, first by the pressure of expansive bursting and then by the so defined negative pressure, an air suction caused by the vacuum created in the centre by the expansion of gases. The impact of the explosion may have two completely different dynamics on the structure of the target:

• if the device explodes nearby or on the surface of the target, as in the case of bombs, or

• if the device explodes inside the body of the target, as in the case of explosive bullets.

With this invention, an attempt is made to respond to both the situations.

The state of the art .

The present invention combines two hitherto distinct areas which, starting from opposite principles and needs, have independently developed their respective techniques: the sector of defence explosion- proof walls and the sector of firearms.

This invention transforms a defence installation such as the wall, passive by definition, into a dynamic weapon that, at the moment of the explosion, reacts and counteracts its effects in an active way.

The state of the art of both areas will be brought to clarify the inventive steps. Anti-explosion barriers: up to now, the field of barriers has hindered the active impact of explosions in a passive way,

• by the strengthening of the solidity of inert artefacts and their resistance to the impact with the parts of the exploded projectile and to the shock wave created by the explosion,

• or by reinforcing their resilience and their grade of absorbing its effects as much as possible.

One of the major problems to be faced by these structures are the delayed burst projectiles, created with the intention of bringing the explosion of the charge inside the artefact, blasting after the body of the projectile has penetrated into the structure thanks to the power of the launch and the robustness of its external body; this explosion, releasing the gases under pressure produced by the explosion inside the structure of the target, tends to break the unitary and compact structure of the wall in the points of greatest fragility or weakness, creating the greatest number of fractures possible, until the gases create paths to go outside and relieve pressure.

Resistance and resilience of the materials were also contrasted with this explosive force, with various kinds of improvements, all aimed to make the explosion-proof walls more and more compact, solid, and non- penetrable. Firearms: among the state-of-the-art applications underlying this invention, there are also the innovations made in the last century to firearms with the introduction of devices for the re-use of the power of firing gases to reduce their side effects, thanks to the creation on the barrels of obligatory paths that lead the gases, before being expelled, to give the weapons thrusts that go in a direction different or even opposite to the initial one; in small arms, this innovation has led to two innovations, namely muzzle brakes, and compensators, i.e. those devices that are applied to the muzzle of the barrels to reduce the recoil force (in the case of muzzle brake) or the detection (in the case of compensator), or both.

The muzzle brake, present in howitzers such as in small arms, acts in such a way as to mitigate the recoil, that is the retrograde movement of the weapon; like the compensator, it is a solid body, equipped with one or more pairs of side vents, assembled at the muzzle of the fire barrel; these devices convey the firing gases in the opposite direction of the recoil of the weapon, contrasting it with the jet effect; even the impact that the firing gases have against the front wall of the holes or vents before being deflected outwards provides an important forward thrust to the body of the weapon, which counteracts the recoil; particularly important is the thrust received in the instant in which the outgoing bullet passes the vent holes over, freeing them, but still blocking the final section of the muzzle.

Novelty and inventive step

This invention overcomes the inert behaviour of the defensive wall by introducing the improvement of a solution already at the state of the art in anti-seismic constructions but not yet applied to the specific field, namely that of the "moving wall" introduced by me with the patent EP3717088, which creates a wall that no longer has the behaviour of a solid and compact whole but which reacts to the thrusts allowing the independent movement of each single element that composes it, making the overall behaviour similar to that held by a bag of gravel, otherwise from which, however, every single element moves only in a preordained way; in addition to not opposing a compact and integral wall to blasts, the invention introduces active dynamics to counteract the explosive forces with the aforementioned anti-recoil techniques used in firearms, adapting them to reusing the blast gases not to avoid recoil but to avoid the disintegration of the artefact, also directing any projectiles in the desired direction.

The aspect of novelty and inventiveness starts from the change of point of view and terminology, identifying into an inert wall, impacted by an explosive bullet, the elements that can make it assimilated to a firearm.

So far, even if not identified yet, we already had three components:

• an explosion chamber, created in the random point of the wall where the explosive bullet impacts,

• an explosive charge, carried into the wall by the bullet itself

• missiles or bullets, i.e. the fragments of the bullet and the fragments of the impacted wall. This invention adds:

• firearm-barrel-bores shaped holes inside the wall, to convey the pressure of the gases of the explosion, and any bullets, in preordained directions, and

• a muzzle brake at the end of the created barrel bores, their muzzle, that directs the gases and projectiles in harmless directions and reuses the pressure of the gases to hinder the explosive thrusts and to compact the structure.

The invention: it is composed of an external container (Figs. 2, 4 ), that acts as a first defensive shield and as a muzzle brake, and of one or more internal walls (Figs. 3, 10, 11), whose elements (Figs. 7-9, 14, 15) are internally crossed by aligned holes (Figs. 16, 17), that create channels along the entire structure of the wall (Figs. 12, 13), which will have an equivalent function to that of barrel bores in firearms, that is to convey the gases of the explosion laterally outside, towards the walls of the container, where they will be expelled after having opposed the disintegrating action of the explosion using its own pressure and impact forces to compact the structure instead of for its disintegration, by varying the vector direction of the expanding gases that act on a wall that does not react in solidarity to the impact but that is already fragmented in a preordained way and whose single elements are ready to move in the predetermined directions.

This muzzle brake and the bores created inside the wall will turn the passive defensive construction into a dynamic weapon system upon the arrival of the explosive bullet that, hitting the wall, will at that moment lead to the creation and the assembly of all the components mentioned above.

In the case of a traditional bullet, in the absence of explosives, shocks given by the impact will be absorbed by the moving wall, which will nullify the disruptive effects with the innovative structure proposed. Similarly, in the event of a bomb that invests the wall only externally with the shock and pressure of the explosion and with the debris, the innovative structure of the inner wall will guarantee the absorption of the shocks and the maintenance of the integrity of the structure.

Presentation of the invention

The dynamic anti-blast wall, object of this invention, is a modular wall because it is made up of one or more identical modules, which can be assembled in the quantities and dimensions suitable for the desired protection.

One module will therefore be submitted.

The module (Fig. 1) consists of a container (Figs. 2+4), described later on, inside which is inserted a revised version of the wall built with the technique described in my patent EP3717088 to which reference is made, which goes beyond the concept of the wall as a compact and integral whole and which allows the construction of a "moving wall", in which the individual elements remain free to move, but only along the axis of the wall facade (Figs. 3, 10, 11); the needs of the situation, the required dimensions or the need for resistance to hypothetical explosions of greater capacity may require the reinforcement of the module by inserting more rows of elements in the container, obtaining a wall of greater thickness, or by inserting and positioning more walls in the same container, separated by empty spaces or by inert or shockproof material, or by metal walls or other solutions already in the state of the art, to improve their effectiveness.

The dimensions of the external container, its thickness, and the specifications of the materials used for its construction may vary in relation to the needs of the situation, as well as the quantities and arrangement of the vent holes, described later on.

Both for the container and for the internal elements, the choice of materials, dimensions, and proportions of the individual parts will be dictated only by the effectiveness of the whole structure and improvements and advances in the state of the art could vary the type of materials used, remaining within the perimeter of protection.

The modular elements (Figs. 7-9, 14-17)

The modular elements have shape and characteristics described in the aforementioned patent EP3717088, but are modified by inserting one or more holes inside them.

Made to allow the passage of air and gases under pressure at the moment of bursting, the optimal section of these bores is uniform and circular and they are positioned so that, once assembled, the holes on the contiguous faces of aligned elements match, and that their alignment creates longitudinal seamless holes that will have the shape and the behaviour of the bores of the gun barrels (Figs. 12-13); like the fire barrels, these bores may have a smooth internal surface or have helical grooves, called riflings, carved into the bore wall; once the wall in place, they will be transversal to the ground and symmetrical, creating a series of hollow barrel bores in the whole structure, arranged transversely between two contiguous internal faces of the container, reminding in the section of the wall the hypotenuses of right-angled triangles having their sides on two internal faces of the container.

When the elements are made of composite materials, the internal walls of the holes, the barrel bores, can be coated with metal or plastic, or other materials suitable for the purpose, to increase their resistance at the time of the passage of gases.

Patent EP3717088 forecasts the use of finishing and connection elements, while in this case only modular elements are used, which are rhomboid-based parallelepipeds; their arrangement in lozenges, in diamond disposition, will therefore lead the assembled internal wall not to adhere to the container, but to touch it only with the edges of the internal faces of the outermost elements (Fig. 6), creating a series of empty spaces, in the shape of a triangular prism, arranged all along the entire perimeter of the internal sidewalls of the container, spaces utilised for the reuse and the expulsion of the pressured gases (Figs. 1, 6).

The container (Figs. 2+4)

The container is a hollow artefact of reinforced concrete or other materials, with or without internal or external reinforcements to increase its resistance to shocks and pressure, normally in the shape of a six-sided parallelepiped (Figs.l, 2+4) of which the wider faces form the front and the back of the wall and the others are the sides, top, and bottom faces.

For clarity we use the following definitions from here on: Face "F"(Figs. 4, 5): the front face of the container, i.e. the external face of the defence wall from which the possible attack is expected to come; Face "P": the opposite, rear face of the wall, facing the area to be protected.

Face "B": the lower face, the base on which the container rests. Face "T": the upper face (top) of the container or of the wall.

Looking at the wall facing the front, we name Face "L" the side face on the left and Face "R" the lateral face on the right.

Although there are no limits to its dimensions, for logistical reasons the industrialized container module will have the maximum overall dimensions equal to those of the 20-foot container, i.e. 6058 mm in length, 2591 mm in height, and 2438 mm in width, including any external reinforcements. The external facade "F" of the wall, that is the one that could be hit by the bullet and then by the explosion, will have vent holes along the internal perimeter, in correspondence with the aforementioned empty internal spaces, holes that will allow these spaces to carry out the function of decompression chambers at the moment of the explosion and, in fact, of the function of muzzle brake (Figs. 1, 5+6).

Dynamic action.

Into these prism-shaped rooms communicating with the outside, the bores internal to the elements also open up, holes that, in place, continue seamlessly along their entire transverse axis of the wall, throughout the aligned elements (Figs. 12, 13).

Wherever the wall is impacted by the internal explosion brought by a delayed burst projectile, the displacement of air and pressure will be directed, through the holes, towards the vent chambers created between the internal elements and the container. The expansion of the gases will find these hollow paths towards the lateral vent holes, after a pressure's action towards the walls of the prismatic chamber; in those chambers, while the wall of the container will remain still, the other two faces created by the elements of the internal wall will tend to be pushed internally, so pushing their contiguous elements, free to slide and predisposed to possible movement along the axis of the wall and so on from contiguous element to contiguous element, along the entire row.

Since this will happen along all the internal walls of the container, all the elements will be pushed towards the centre of the wall, actually towards the only point where an empty space has just been created, due to the explosion, going to close it temporarily, to return at the end of the thrust in the original position.

With the exception of the point of impact, a few moments after the blow received, the wall will be ready to receive the next blow without having suffered further structural damage.

After appropriate evaluations, vent holes in various numbers and sizes can also be drilled along the sidewalls of the container ("L" and "R" and "T"), to discharge the forces of the blast also laterally and not only frontally. These options have not been displayed in the example.

Industrialization, an example of module The container

In the utilized example all measure are expressed in millimetres (mm). The external dimensions of the container are, 2400W x 2400H x 1000D These measures will allow and ease its portability and modularity.

The container is an external frame, a hollow cube of reinforced concrete; the thickness of its walls is 200, with a double internal iron rod grid of 10 mm in diameter, with openings of 90 x 90.

While the side and rear walls are entirely made of reinforced concrete, to form a compact and integral body, in the front face of the container, measuring 2400 x 2400, the reinforced concrete is not used along its external perimeter; the fagade will be kept assembled to the rest of the container only thanks to the iron grids that reinforce the concrete. There will be a central part of the fagade in reinforced concrete, measuring 1800 x 1800, surrounded by a band of 100 of iron rod grid only, between the central body of the fagade "F" and the thickness of the side faces of the container (200), which will allow the gas to be vented. The internal space of the container is a hollow cube measuring 2000 x 2000 x 600.

The internal elements

Two walls are positioned in the internal space of the container, i.e. two parallel rows of reinforced concrete elements laid simply side by side, following the technique of the aforementioned patent, using only modular elements arranged in lozenges, without inserting any element of completion.

Modular elements are parallelepipeds with two square bases of dimensions 140 x 140, to form the faces of the wall, and a height of 280 that becomes the thickness of the two internal walls and that form the four internal faces of the elements, each one measuring 140 x 280.

The external faces of the elements that make up the wall are squares measuring 140 x 140 with diagonals of 198, so the elements in position will have a height and width of 198 x 198. Each internal wall will consist of 181 elements arranged in a lozenge pattern or 10 rows of 10 elements interspersed with 9 rows of 9 elements each, for a total of 362 elements for each module filled with two internal walls. Total dimensions of internal walls side by side will be 1980 x 1980 x 560 mm set into an internal space of the container 2000 x 2000 x 600.

The 20/40 mm difference will avoid possible problems due to material tolerances and volume variations due to thermal excursions.

The result will be an internal wall that almost touches the internal faces of the container with the vertices of the elements of its outermost rows. The empty internal spaces between the container and the outermost elements of the two walls will have the dimensions of a prisms 560 deep and with a triangular section of 198 along the base, the container wall, and with two sides of 140, i.e. the sides of two modular elements. The height of this triangle is 99 mm, which is the same opening (100) left along the edges of the facade "F".

The 10 mm rod will also be used to reinforce the concrete of the elements and will be made to come out for 40 mm in the two lower faces, to form the pins of the elements, while the grooves on the upper faces will have a width of 12 mm and a depth of 45 mm to allow sliding effortlessly and with play of the pins in case of movement.

In the lozenge arrangement of the elements, grooves will all face upwards and pins all face downwards.

Every single element will have in the centre of an internal face a hole/bore parallel to the external faces, orthogonal to the upper internal face from which it starts and which runs parallel to the base of the element reaching the opposite lower internal face (Figs. 14-17).

In the example proposed, the bores have a constant circular section, with a diameter of 60, so the internal bore will be a hollow cylinder with a diameter of 60 and a height of 140. In the example and in the drawings, nor the metal lining of the inside of the bores, neither their rifling, which are desirable in practical application, are provided.

The elements of a wall will be arranged rotated by 180° along the vertical axis with respect to the elements of the other wall, thus arranging the reciprocal internal bores orthogonally, with an X-shaped perspective arrangement of the barrel bores.

For details regarding the reaction of this moving wall to shocks of any kind, please refer to the cited patent. This structure, already fragmented into 362 elements, independent and free to move, will also have 38 bores ready to convey the pressure wave towards the outside the module; at the moment of the blast, it will use the pressure of the gas against the internal walls of the container to compact the walls, making the modular elements of the internal wall slide towards the point emptied by the explosion, in the meantime diverting the gases and any fragments towards the front direction from which the attack came, helping the defence and achieving the purpose of this invention of which the protection is asked.

The modular structure will also allow a quick replacement of entire damaged modules and their maintenance, a quick restoring of the efficiency of the wall, and the storage of pre-assembled modules ready for use. Finally, the independent and dry-assembled elements will allow maintenance of the module with the replacement of only the elements damaged by the explosion with new elements that will bring it back to its full efficiency.

Brief description of the drawings

Fig. 1: Perspective view of a fully assembled module (the modular kit) ready for use, with the thickness of the front wall (face F) in transparency, to facilitate the understanding of the assembled whole.

Fig. 2: Perspective view of the container, empty and without facade F Fig. 3: Perspective view of the internal wall of modular elements, with 3 missing elements to facilitate the understanding of the assembled whole, positioned in the container. Figs. 4 and 5: Perspective view of the front wall (face F) of the container with vent holes along the perimeter.

Fig. 6: Perspective view of the internal wall positioned into the container, with 3 missing elements to facilitate the understanding of the assembled whole. Figs. 7-9: Perspective views of the 3 missing modular elements.

Fig. 10: Example of an internal wall assembled: bottom-up perspective view

Fig. 11: Example of internal wall assembled: top-down perspective view Fig. 12: Section of an internal wall assembled: bottom-up perspective view

Fig. 13: Section of an internal wall assembled: top-down perspective view,

Figs. 14-17: perspective views of the modular element, whole and sectioned along the hole.

Claims

1. Kit for the realization of a modular anti-blasting wall, comprising at least one polyhedric container having at least six faces, containing at least a plurality of modular elements having the shape of a parallelepiped with two bases and four faces extending between the bases, and having at least one female element and/or one male element on at least one of their faces, shaped so as to be coupled with play with the male/female element of a contiguous element, whereby the female elements have a groove shape and the male elements have a pin shape apt to be inserted and to slide along said grooves once in place, and whereby, in said modular elements, the grooves run parallel to the bases, whereby said modular elements can be connected and assembled together in absence of any sort of binder or joint, and whereby the bases of said modular elements can be assembled in static equilibrium with a diamond configuration along a plane parallel to the direction of the force of gravity, such that any single modular element is connected with play to at least a contiguous element and remains free to move also once in place, and all the faces of the modular elements in contact with the faces of other modular elements identify reciprocal, non-horizontal, sliding planes transverse to the direction of the force of gravity, characterized by the fact that, when the kit is assembled, the polyhedral container contains at least a plurality of assembled modular elements and that the polyhedral container has at least one vent hole on at least one of the faces and characterized by the fact that each modular element has at least one internal bore that runs from one of the four faces to the opposite one, parallel to the bases, and characterized by the fact that, once in position and assembled the modular elements inside the container, the holes on the faces of the contiguous elements match and are aligned to create a continuous bore, transversal to the walls of the container, which crosses all the elements until the internal faces of the container, and characterized in that the diamond arrangement of the modular elements inside the container creates hollow spaces between the internal walls of the container and the faces of the assembled elements closest to the internal walls and characterized in that the vent holes on the container walls are positioned in correspondence with said hollow spaces, into which the bores inside the assembled modular elements also open.

2. Module for constructing anti-blast walls constructed with the use of at least a kit according to claim 1.

3. Process of constructing a module for constructing anti-blast walls using at least a kit according to claim 1.