EP0179821B1 - Protective wall for constructions - Google Patents

Abstract

To protect a construction against terrorist acts, in particular explosive attacks, a protective wall requiring considerable time for destruction is placed in front of it. This protective wall consists of a row of pillars from which are suspended a support net (4) and shielding elements (5) in the form of a box structure, constituting a closed suspended wall (H1), attached by hooks (16) to the net. Each shielding element (5) comprises an armoured front plate (12) and a filling in the form of an inflammable material (13) in which igniting devices (14) are embedded, being triggered under the effect of the firing of the explosives or other means of attack, thus setting fire to the inflammable material (13). The flames and fumes thus produced prevent the terrorists from proceeding further.

Description

The invention relates to a system for protecting buildings from terrorist attacks, in particular explosives, with a protective wall in front of the building.

For certain structures, such as Power plants, radio and television transmitters, high-voltage line masts, military installations or the like. there is an increasing risk of acts of terrorism, mainly for political reasons.

Therefore, in the case of already known protective systems of the aforementioned type, the outer walls of the endangered structures are at a relatively large distance from z. B. provided about 100 m relatively high barbed wire fences or erected concrete walls. However, these obstacles can be overcome relatively quickly by terrorists with special tools or by blasting, so that the time to alert the police and their appearance at the crime scene is too short to destroy the exterior of the building, the terrorists' intrusion into the building, to prevent their actual work of destruction inside the building and their escape. In addition, for reasons of space, there is often no possibility locally to erect a protective wall or to arrange it at the desired large distance from the building wall facade. Sufficient security to prevent logistically mostly carefully prepared acts of terrorism is therefore usually not given at all. The purpose of the invention is to remedy the above-mentioned disadvantages of the known protective systems, and it is therefore based on the object of creating a protective system of the type mentioned at the outset, in which the protective wall in front of the outer wall of the structure is not or only with great difficulty and therefore A relatively large amount of time can be overcome by terrorists, whereby the time required to partially destroy them should be as long as possible, so that the time required to alert the police, to show them in time at the scene and thus to thwart the actual terrorist attack directed against the building itself, how, if possible, to ensure the arrest of terrorists with greater certainty than before.

Accordingly, the invention relates to a protective system of the type mentioned at the outset, which according to the invention is characterized in that the protective wall is provided with a combustible mass to delay the terrorist attack due to the development of flames and smoke, and that ignition devices are embedded in this in that these an explosive explosion can be triggered by deformation of the protective wall and contain two coordinated amounts of two spaced-apart compounds or raw materials that only react chemically with one another exothermically when they come into contact with each other to trigger and thus set the flammable mass into fire.

The progress achieved with the invention compared to the previously known protective systems consists in the fact that in the case of acts of terrorism it is usually practically impossible to overcome the protective wall and, even when using highly developed professional methods of perpetrator, is so delayed by the intense heat and smoke development of the combustible mass ignited by the ignition device that Even if the protective wall could finally be overcome by the terrorists, the actual terrorist attack on the object to be destroyed can be thwarted with sufficient certainty thanks to the timely alerting of the police to the relatively large amount of time required for the local destruction of the protective wall.

Due to the many times greater effectiveness of the protective wall according to the invention, the time gain that can be achieved by choosing a relatively large distance between the protective wall and the building facade tends to be less important. Therefore, the protective system according to the invention can also be used where the local space conditions do not allow such a large protective distance; this is particularly the case if the protective wall consists of two or even several wall walls arranged one behind the other, formed from armored elements and each self-contained.

Further features and advantages of the protective system according to the invention will become apparent from the following description of an exemplary embodiment of the invention in conjunction with the associated drawings.

• Fig. die Schutzwand der Anlage, in einem vertikalen Querschnitt,
• Fig. 2 ein Panzerelement der Schutzwand nach Fig. 1, in das zugehörige Tragnetz eingehängt, in vergrössertem Massstab in einem vertikalen Querschnitt,
• Fig. 3 einen frontalen Ausschnitt aus der Schutzwand nach Fig. 1, in einer räumlichen Frontalansicht,
• Fig. 4 eine in der brennbaren Masse eingebettete Zündvorrichtung gemäss Fig. 2, in einem vertikalen Querschnitt, und
• Fig. 5 eine Panzerplatte nach Fig. 2, mit den über ihre Grundfläche verteilt angeordneten Zündvorrichtungen nach den Figuren 2 und 4, in einer frontalen Draufsicht auf die Panzerplatte.

In the drawings, an embodiment of the protection system according to the invention, which at the same time also essentially illustrates the mode of operation of the system, is shown schematically. Show it:

• Fig. The protective wall of the system, in a vertical cross section,
• 2 shows an armored element of the protective wall according to FIG. 1, suspended in the associated support net, on an enlarged scale in a vertical cross section,
• 3 shows a frontal section from the protective wall according to FIG. 1, in a spatial frontal view,
• FIG. 4 shows an ignition device according to FIG. 2, embedded in the combustible mass, in a vertical cross section, and
• 5 shows an armor plate according to FIG. 2, with the ignition devices according to FIGS. 2 and 4 distributed over its base area, in a front plan view of the armor plate.

In Fig. 1 is a vertical outer wall of the structure to be protected, e.g. a power plant, designated 1. The wall 1 is placed at a relatively short distance from a generally designated 2, also vertically extending protective wall. The protective wall 2 consists essentially of supporting pillars 3, two support nets 4 attached to them and armor elements 5 suspended therein.

The supporting pillars 3 are arranged in a row running parallel to the outer wall 1 of the building and at their upper ends with one another same, projecting forward cantilever arms 6, on each of which live in two mutually parallel verticals a support net 4 is attached. In this way, two vertical, mutually parallel walls are formed from the two support nets 4 and the armor elements 5 suspended therein, the armor elements 5 placed against one another with horizontal and vertical butt joints representing two self-contained hanging walls H1 and H2 (cf. also Fig. 3 with the front hanging wall H1). The cavity between these two hanging walls is filled with barbed wire rolls 7. The protective wall 2, which here is, for example, about 1 m thick and with its rear wall surface 9 is about 1 m distant from the facade 10 of the building's outer wall 1, is protected against atmospheric precipitation by a narrow, inclined roof 8.

According to FIG. 2, each armor element 5 consists of a cuboidal steel sheet box 11 which is closed on all sides, a armor plate 12 which is inserted in the front of its cavity and a combustible mass 13 which fills the remaining box cavity on the back, and for its ignition from a plurality of ignition devices 14 which are inserted into the combustible Mass 13 are embedded.

The mode of operation of a single ignition device 14 will be explained in more detail later with reference to FIG. 4; it should only be mentioned here that this ignition device has an exothermic, i.e. Heat-releasing chemical reaction of two chemical compounds generates a high temperature in a matter of seconds and thereby quickly sets the surrounding combustible mass 13 on fire, which in turn immediately generates a great deal of flame heat and strong flue gases.

The sheet steel box 11 is closed by a rectangular sheet steel plate 15 welded onto its rear side. The armor element 5 is provided with hook-like brackets 16 welded on the rear to the sheet steel plate 15 and hung with them into the support net 4. The thickness of an armored element 5 here is, for example, approximately 80 mm in the exemplary embodiment according to FIG. 2.

According to Fig. 3, the armor elements 5 are arranged one above the other in horizontal rows, wherein they are joined together with vertical butt joints 17. The armored elements 5 are identical to one another here, and their butt joints 17 are offset from one another from row to row. 3, the length of a tank element 5 is, for example, approximately 2 m, its height e.g. approx. 1 m. FIG. 3 also shows that and how a self-contained front hanging wall H1 is formed by the front support net 4 and the armor elements 5 suspended therein (cf. also FIG. 1 with FIG. 3).

FIG. 4 illustrates that or how a single ignition device, generally designated 14, is embedded in the combustible mass 13. The ignition device 14 here consists, for example, of a glass ampoule 18, an amount of a chemical compound 19 of a liquid “mold type” (or “physical state”) and an amount of another chemical compound 20 of e.g. powdery, i.e. thus fixed «form type».

The two chemical compounds 19 and 20 are substances between which there is great specific connectivity, i.e. There is a high so-called «chemical affinity», so that when they are brought together, a rapid, exothermic chemical reaction takes place and thus immediately releases a relatively large amount of heat and therefore a relatively high temperature, it is the ignition temperature for the combustible mass 13, is generated, although the course of the chemical reaction depends not only on the substances involved, but also (apart from the temperature and pressure) on their quantitative ratio.

If terrorists attack the protective wall 2 (cf. FIG. 1) with explosives, at least one of the ampoules 18 lying in the area of the explosive device bursts due to the deformation of the armor plate 12 affected thereby; this is all the more certain since the length of each ampoule is a multiple of its diameter, i.e. the ampoule is relatively “slim”. When the ampoule 18 bursts, its contents pour out, i.e. the filled amount of the liquid compound 19, into the amount of the solid compound 20 immediately surrounding the ampoule, which in a matter of seconds triggers the chemical reaction required to ignite the combustible mass 13 between the two substances 19/20. The combustible mass 13 set on fire immediately develops - it can consist, for example, of largely shredded old car tires (shredded tires) - in a large amount of flue gases, but at the same time also a great deal of heat, which, of course, at least greatly hinders the continued work of the terrorists and thereby significantly delayed.

A terrorist attack using explosives would therefore initially proceed as follows:

If the front hanging wall H1 of the protective wall 2 (cf. FIG. 1) is partially demolished and the combustible mass 13 burns, the terrorist on the ground takes cover; then the explosion occurs through the explosion; but until he gets up from his covering, there is a fire inside the wall; but then he has the problem that he has to extinguish the fire (possibly using a hand-held fire extinguisher) in order to be able to progress in his further work.

It is only and only by destroying a tank element 5, i.e. of the associated steel sheet box 11 and the armor plate 12 inserted therein, the fire of the combustible mass 13 is triggered, but if a armor element 5 e.g. is destroyed by explosion, the combustible mass 13 in a matter of seconds, e.g. set on fire by igniter 14 in two seconds; however, once it burns, it is difficult to extinguish.

If an explosive charge is used in the terrorist attack, at least one of the armor plates 12 is torn or at least bent, i.e. very deformed. As a result, however, at least one of the ampoules 18 located in the armor element 5 is broken as a result of the detonation, and the liquid 19 then emerges from it and reaches the powdery, i.e. firm connection 20. If, however, an oxygen lance or a welding torch is used in the terrorist attack, the combustible mass 13 is set on fire anyway due to the enormous local heat development which occurs, in which case the function and effect of the ignition device 14 may function as an “ignition booster”. would come. The ignition device 14 is therefore of very great importance for a terrorist attack by means of an explosive charge, especially since explosives in particular are probably the most widely used aid for serious acts of terrorism today.

The ignition device 14 is embedded in the combustible mass 13, for example, as follows:

A recess 21 was formed in the combustible mass 13, which was initially only partially filled into the steel sheet box 11 (see FIG. 2), and the amount of the solid connection 20 was then pressed into it (see FIG. 4). Thereupon, the ampoule 18 filled with the amount of the liquid compound 19 was in turn pressed into the amount of the solid connection 20, so that it is encircled approximately semi-cylindrical by the latter on the front side exposed to the terrorist attack. Finally, the ampoule 18 was on the back, i.e. on the side facing the power plant facade, covered with the remaining combustible mass 13 to be used (cf. FIG. 4).

The overall operation of the protective system previously described with reference to the drawings will be explained in more detail below.

Nowadays terrorists work with diamond drill bits, welding torches, oxygen lances or explosives. The defense against explosive attacks on buildings, which are now becoming increasingly common, has already been described in detail. The defense against terrorist attacks, in particular by means of an oxygen lance, is now explained in more detail, but the following explanations about the gradual advancement of the terrorists and their constantly increasing disability also have general, fundamental importance for the explosive attack.

In the event of an act of terrorism using an oxygen lance, the armored plate 12 of an armored element 5 of the lowest row of elements would be perforated on the front hanging wall H1 in the worst case. However, one of the ignition devices 14 would be triggered, which would immediately set the combustible mass 13 on fire, which would cause a strong development of flames and flue gases. The same applies to the attack using a welding torch. In order to be able to slip through, the relatively narrow hole in the armor plate 5 has to be expanded many times by the terrorists, but they are at least severely hampered by the flames and the escaping hot smoke gases, which hinders their further work, i.e. the attack on the second rear wall H2, delayed accordingly, if not impossible.

For the party affected by the terrorist act, it is first and foremost about saving as much time as possible to ensure that the police force on standby is ready at the scene of the crime with sufficient certainty.

If a terrorist were able to get between two adjacent ignition devices 14 when attacking the front hanging wall H1 by means of a diamond bit, the borehole would then have to be expanded many times over in order to be able to slip through. In this case, however, at least one of the ignition devices 14 located in the borehole enlargement area would be triggered, making the further work of the terrorist more difficult.

If the second rear wall H2 is partially destroyed as well, the additional flame and flue gas development, with increasing irritation, nervousness and fatigue of the terrorists, is likely to thwart a professional, logistically prepared terrorist act before the actual object, i.e. in this case, too, only the outer wall of the building is reached. But then the police force responsible for the building has long been alarmed and has usually arrived at the scene. However, if the police are still on the move, then the actual terror attack on the building itself begins, so that there is still a relatively high probability that the physically and morally impaired terrorists will attack them now Make the outer wall of the building 1 harmless and arrest it.

With careful mutual coordination of the distance between the two hanging walls H1 and H2 with the distance between protective wall 2 and building outer wall 1 (see FIG. 1) in conjunction with the wall thicknesses to be selected for the two hanging walls and the type and quantity of the combustible mass 13 to be used the time saved until the police arrive on time can be further optimized by the increasing disability of the terrorists as a result of the spatial conditions that are disadvantageously changing for them.

If the terrorists should succeed in overcoming the first hanging wall H1, they have to get closer to it so that they can also tackle the second hanging wall H2 with the oxygen lance or the welding torch, and they must, if they can also overcome it should then continue to advance under increasingly difficult spatial and physical conditions, to get to the outer wall of the building in the first place.

The protective wall 2 is expediently provided on its two narrow end faces with end walls which extend as far as the facade 10 of the outer wall 1 of the building and extend up to the roof 8 (cf. FIG. 1).

The fact that the cavity between the two hanging walls H1 and H2 is filled with barbed wire rollers 7 (see FIG. 1) makes it even more difficult to overcome the protective wall 2 for a terrorist attack and thus further delayed.

The police alarm system is already known and is therefore not shown in the drawings for greater clarity. The question here is e.g. a vibration button serving as a mechanical pulse receiver, which triggers the alarm in the police station via a pulse converter, which converts the mechanical pulses into electrical ones. Other donors, e.g. Thermal sensors and / or special microphones should also be considered here.

Various deviations from the protective system previously explained with the aid of the drawings are possible. Thus, instead of arranging two hanging walls one behind the other, depending on the importance of the object to be protected, three or, on the other hand, only one could be provided. Instead of letting the pillar row run parallel to the outer wall facade of the building, it could - depending on the local conditions - deviate more or less from the parallel extension. Instead of providing only a single support net to form the hanging wall, several net tracks could also be attached next to one another on the supporting pillars in the relevant vertical plane. Instead of inserting only a single armor plate into the armor element, two or more could also be provided for each element and arranged side by side, one above the other or one behind the other.

The invention is therefore in no way tied to the embodiment of the protective system previously explained with reference to the drawings, rather the details of the embodiment within the scope of the invention, which is determined by the claims, can be varied.

Claims (6)

1. Arrangement for the protection of buildings from terror attacks, in particular attacks using explosives, with a protective wall placed before the building, characterized thereby, that, for a time delay of the terror attack by the generation of smoke and fumes, the protective wall (2) comprises a combustible mass (13), in which ignition devices (14) are embedded which are capable of being set off by a bomb explosion through a deformation of the protective wall (2), and, for setting off and, therewith, setting on fire the combustible mass (13), contain in each case two coordinating amounts of two compounds (19 and 20) or elements separated from each other and reacting only by mutual contact exothermically chemically together.

2. Arrangement as in Claim 1, characterized thereby, that with each ignition device (14) one (19) of two in this contained chemical compound (19 and 20) is liquid and filled in an ampoule, and the other (20) is solid; and that the ampoule (18) is enveloped on its front side by the solid compound (20).

3. Arrangement as in Claim 1, characterized thereby, that the protective wall (2) consists of a row of supporting pillars running at least approximately parallel to the outer wall (1) of the building, at least one support net (4) hung thereon arranged in a vertical plane, and armour elements (5) hung therein forming a self-contained suspended wall (H1 resp. H2), and that the armour elements (5) are box-type constructed and in the cavities thereof provided in each case with at least one front-side armour plate (12) and a rear-side filling of the combustible mass (13).

4. Arrangement as in Claims 1 to 3, characterized thereby, that the box-type armour elements (5) are closed on all sides.

5. Arrangement as in Claim 3, characterized thereby, that the supporting pillars (3) are provided on their upper ends with brackets (6) extending towards the attacked side, onto which in each case at least one support net (4) is hung in two vertical planes parallel to each other and that both support nets (4) are provided with armour elements (5) hung therein, forming thereby two suspended walls (H1 and H2) at a distance form each other.

6. Arrangement as in Claim 5, characterized thereby, that the cavity between the two suspended walls (H1 and H2) is filled with rolls of barbed wire (7).

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