SA94150102B1 - Anti-explosion pads and how to use them - Google Patents

Abstract

Abstract: The invention relates to high efficiency anti-blast pads comprising multiple sheets of expanded metal mesh separated by a core layer of porous material such as fiberglass, cotton wadding or a group of ellipsoids or small balls formed from expanded metal mesh 0 when covered A wall or other structural component, the layered pads efficiently scatter the vibrational waves and thermal effects of a bomb blast at close range.

Description

Anti-Blast Pads and Method of Their Use Full Description BACKGROUND: This invention generally relates to anti-blast Pads which can be used to protect structures against the catastrophic effects of accidental or undesirable explosions. More specifically, the invention includes anti-bursting layered Pads comprising 0 of several layers of lightweight expanded metal mesh. The invention also includes Load, a method of using these Pads to take advantage of their anti-explosion properties. As is well known; The production and use of explosives is a comprehensive and far-reaching industry. Scientific research over the centuries has developed many useful applications for known explosive materials; Lay in that industrial blasting used in the mining industries; building 0 roads; As well as harnessing very small explosions for use in internal combustion engines. The military use of gunpowder and other explosives in guns is also well known; artillery weapons; Bombs and the like. At the same time and by the benefits derived from the useful application of explosives; The world has been forced to endure catastrophic consequences, which also happen more often than not. Loveie Explosives 1 explode by accident (unintentionally); As in the case of explosions in coal mines; fuel tank fields; homes; the cars ; ships; Planes ; and the like. Likewise: The world is faced with incidents in which terrorist or other illegal ol eS bombs are used. Great effort has been made to develop products and methods to protect buildings against the destruction that occurs when explosives detonate near them; Either by accident or for spoiling purposes. Although there has been some progress; Yet the loss of human life and destruction of property by the explosions continue at an unacceptable rate; And that there is a continuous intensive effort to find economical, effective and practical ways to improve anti-blast products and technologies. h00.”

However, the objective of the present invention is to provide a felt material (Pads) that has significantly improved blast suppression properties. The other objective of this invention is to produce an anti-explosion Pad that contains very light weight components that act in a very effective way to disperse the vibration © waves resulting from the explosion of an explosive. Another goal is to provide ways to use the new anti-blast Pads to protect buildings that, on the other hand, are subjected to violent destruction as a result of the force of the blasting bomb. There are other goals and features that will become clear by completing the description. 0 General description of the invention: This invention is based on the discovery that walls and other structural elements can be effectively protected against bomb blasts by placing a lightweight Pad between them and the Cua bombs. The Pads contain multiple sheets of elongated metal mesh separated by by a layer of porous material. It was found that the presence of the stretched metal grid 1 causes deflection and scattering of the vibrational waves resulting from the detonation of the explosive material; So that the wall or other structural element retains its physical integrity despite the occurrence of an explosion. Therefore, the product of this invention is a layered anti-blast Pads comprising a Jf sheet of expanded metal mesh; a second plate of elongated gastric reticulum; © and an inner core layer of air-permeable material Jai the first two pages Ally mentioned . And in one of my favorite apps; The Pads are held between the front and rear covers + the expanded metal mesh sheets are made of slit metal foil such as magnesium alloy metal while the inner core is a porous material such as fiberglass; or cotton pads; or a collection of small vo (quasi-spherical) spheroids (Jia (ellipses or spheres) formed from the elongated metal lattice). laugh"

P The invention also includes a method for protecting structures against the impact of blasts which includes placing layered anti-blast Pads of the nature described above between the said structure and the explosive material. Explanation of Drawings 0 Fig. 1: My hometown of a cross-section of the anti-explosion Pad sal lll of this invention » showing the different constituent layers. Figure iY Birthplace of a Cross Section for an Optional Variation of Blasting Pads: For this invention; Shows the inclusion of various additional optional layers. Figure “: apical view of the cleaved metal wafer sheet; which can 00 be widened by extension to make the expanded metal mesh usable in the present invention. : shapes of ; to 1 are apical views of the elongated metal meshwork; Which shows the changes in the morphology as the cleaved plate is pulled to open the elongated metal mesh. 0 DETAILED DESCRIPTION Z Referring to drawings 0, the basic anti-blast pads of this invention are shown in figure 1; in which the 01 Pads contain sheets of ¥ and ; Made of elongated metal mesh and separated from each other by an inner core © made of air-permeable material. Although it is not essential to the invention; © It is required for certain purposes to wrap the previous Pads between two front and back covers + and 17 Ll all over the integrity of the Pads and to prevent slipping or shifting of the elements of the Pads from their position. For this purpose the front and back covers 1 and 7 may be joined together by sewing; or stapling or means of fastening known at the seams (sews)

and A Yo the expanded metal used in sheets and; It is formed by slitting a continuous sheet of metal foil in a custom manner and then stretching the slit to turn it into an elongated prismatic metallurgical grid having a thickness substantially greater than

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Foil thickness. With reference to the drawings; The form *cp is a sheet of pide with discontinuous slits intended for the present invention. The length and width of the plate may be chosen from any number of practical dimensions - depending on the size of the anti-blast pads to be produced.

° As shown in Figure oY, plate 01 is provided with unconnected slits 11 in divergent lines parallel to each other, but which cut through the longitudinal dimension of plate 01 . The notches 11 are separated in each line by non-slotted VY segments or indentations; It will be noticed that those slits 11 in each line are in contrast to the gaps 11 in the adjacent lines. Likewise, the VY gaps in each line are different from the 11 gaps in the lines

0 adjacent. Notch lines extend perpendicularly to the longitudinal edges 17 and NY of the continuous plate of the foil. The device for producing slit foil paper is detailed in US Patent No. 0,157,786; dated September 1st + VARY | And when stretching the slit metal foil shown in the figure “by exposing it to longitudinal tension; it turns into an expanded metallic prismatic lattice;» usable as elements

1 © and; 1 of this invention. in tide step; The horizontal surfaces of the foil are raised to a vertical position; So that it takes a honeycomb-like structure. This transformation is explained in the figures; to 7 graphics. The slit Ve metal foil is shown in the figure; before the tide step. and when applying longitudinal tension in the direction of arrow 10; the slits 11 open and turn into eyes 11; The product takes the appearance shown in the figure

© > . Applying more tension leads to a wider opening of the cracks; The product expands to the honeycomb-like prismatic shape » shown in Figure + . By applying more tension, Ode, the structural figure reaches its required terminal point; As in fig. transformation shown in the figures; to 1 be accompanied by an increase in the thickness of the product; The final thickness of the honeycomb-like product is approximately twice the value of the space ;1 between each vo line of slits.

For the purposes of using the anti-explosion Pads of this invention; It requires that the foil be very thin and that the cracks are in each seam and the voids between it.”

Fonts are very small. And accordingly; The thickness of the metal foil used for the production of the metal mesh shall be in the range between 0.748 and 1 millimeter; The preferred thickness is between 0.74 and 7 mm. The length of each slit is 11 in the range between 1 and 7.5 centimetres; The length of the unslitted portions or gaps 11 between each notch shall be in the range between m? to 1 millimeter. The distance ;1 separating the incision lines may be variable; According to the required thickness of the resulting stretched metal mesh. The distance 1 is usually in the range between 1 and ; millimeter; So that the thickness of the resulting expanded metal mesh is usually in the range between ? and A millimeters. The preferred value for a distance of 16 is either 1 millimeter or 1 millimeter. The type of metal used in the metallic wafer can be chosen from a large number of 0 metals or alloys, which may be produced in the form of wafers. For the purposes of this invention, it is preferable to use magnesium alloys with some other compatible materials. And accordingly; and for example ; It is desirable to use Apu magnesium alloy with materials such as aluminum “copper fusion” zirconium ¢ zinc 2106 strontium “radon (electron) Rn (electron) 0 Silicon « titanium 0 + iron » manganese 011801880656 chromium ¢ and groups thereof. Alloys such as those previously mentioned have the property. A value in that it is not only lightweight; strong and flexible; heat conductive; etc. ; But it also has an important property of being non-flammable. A particularly advantageous combination is the magnesium alloy with aluminum and copper. in which aluminum is replaced by: magnesium, which is useful in the practical application of the invention. The magnesium alloy used in the invention must contain at least 70.5% of its weight: of magnesium -magnesium Yo, and we get other advantages if the expanded metal net is covered with the alkaline bichromate de materials. or protozoans; which are effective in preventing any disease.”

No _ combustion which may be initiated by detonating an explosive. and when heated; These materials emit thick vapor that envelops the area and helps prevent the ignition of building materials in the area. And although the plates * and; has been described to this extent in terms of the expanded (stretched) metal grid ¢ the use of cleft but not stretched sheets at the time of formation of the Pads is considered within the study of the invention. It was found that “when the pads are exposed to an explosion; The resulting forces cause the cleft plate to stretch; The elongated metal mesh profile is useful in deflecting the effects of the blast. It should be noted that the inner core© layer may be any suitable air-permeable material such as fiberglass; cotton pads; or any other similar non-woven (non-woven) material. The core material particularly suitable for layer 0 is Ae gana balls formed from an elongated metal mesh. These balls are most effective when shaped like small ellipses. Ellipse figures are produced by cutting sheets of expanded metal mesh (such as those shown in Figures 7) into small pieces and then mechanically shaping them into shape. Vo ellipse. calle and a long range diameter of 010 IF mm. The apparatus intended for producing ellipse figures is described in detail in US Patent No. 076 Arl Rack dated £ sla » 147 1. 7 It is desirable that the thickness of the inner core layer be in the range between 0725 to ve m. The lower thickness than the previous one provides diminished protection; and fish more than that range; Although effective; It adds bulkiness which is considered impractical under most circumstances. For some uses; it requires the layers to be oF; It is bonded to ve in Knit Pads using Front and Back Covers 1 and 7; Which judges at seams A and 4 . Any suitable material may be used for the back cover 1 . However ; It's from huh

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It is essential that the front cover + be made of a breathable material such as a metal or fiber loom; which will allow the vibration and heat waves of the bomb blast to reach the layers of the elongated metal grid 7 and; And allowing those aforementioned layers to dissipate and scatter the aforementioned waves before they reach the structure to be protected. IF FRONT COVER + SOLID© MATERIAL; impermeable The shock waves of the explosion of the explosive will exert all their unweakening force against the impermeable surface and will destroy not only the protective pads but also the structure intended to be protected. It is furthermore necessary that the front cover be breathable as indicated; It should also be placed in a position facing the direction

from which explosive forces will be generated.

1 The invention is not limited to using only two layers of expanded metal mesh; separated by a single core layer. for some applications; including heavy charges of explosives; It is advantageous to use three or four layers of metallurgical mesh separated by a suitable core of porous material. It is also useful in some environments to use one or two sheets of metal mesh joined together in a layer

Vo is alone.

Figure 1 shows one of the applications of this invention; in which double layer is used

For expanded metal mesh placed near the front surface of Pads and other layers of metal mesh; Separated by ellipse-shaped filler layers + fixed behind the front double layer. additional layers of the network

© Mineral and material in the voids Jig Improved blast protection. Referring to the figure © ; The improved 117 anti-blast layered pad contains the layers

YY 40 Yo 0 14 (VA) made of elongated metal mesh separated from each other by inner gates YY 7 ? and YE made of a set of ellipses mentioned above. The front layer VA is composed of a set of layers of gastric network

elongated yo. The VV Pads are contained between the front and back covers, Yo and YU, which are joined together by stitching; Stapling or other common means of fastening such as stitching

YY As indicated earlier in connection with the application in Figure 1; It is necessary that

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Cae permeable to air and to be placed facing the direction from which the front cover 77 and 74 may have 77 Pads of explosive vibrational waves coming from it. Although the cores were shown in the form of ellipsoid figures; which are preferred; It will be understood that the core material may be any suitable air-permeable material such as fiberglass; or fillings ¢ one may make cotton pads; or any other similar non-woven material. pada 0 for some purposes; with different pulp materials in the various pulp layers; For example, as in made of ellipsoid figures and the rest of the core layers of YY with a Pad sald fiberglass core.

Layered Pads of the nature described above provide outstanding protection against the destructive forces of an explosion. Although the ratio of the expanded metal mesh to the total weight of the structure to be protected is very small (i.e. between 106 = 71); The special honeycomb-like structural shape and thermal conductivity of the elongated metal mesh effectively disperses the vibration waves and thermal effects of the near-range bomb explosion. The nature of the light weight of the Pads has been shown in the following table that shows the dimensions; weights

1 And the porosity of the barrier pads represented within the scope of the invention: huh

And 1 Table 1 is the weight of the area density 1 al No. 1 limit | 1 asl 1 aad | aad term 1 term | aad | term term a | Aw 1 A | lowest | Aw 1 A | minimum 1 or 1 maximum metal with reticulated eyes | TYLE | Fe[AVY| EVA | cg] To | | ve) very fine metal with fine retinal eyes | YY | ve) | #AA 4.131 [ANY EVAL a TY faa a Reticular Eyes Metal | 61 | VY | Ee | ONY EVA | [| te | arr

TY | ge PF ANY | EVA | gE | Metal with fine mesh eyes | pw ay ge Pre Lavy | eva | veg mf [ary] voy | Reticulated eyes metal Y very accurate pry em ay ge Pre lav | eva leg] to | ery metal with fine mesh eyes | Very net = ay Lge + any eva | egg] p | died vy | Metal with Reticulated Eyes 1" Very accurate huh".

-17- z z z z 1 1:2 |. Lary] Mf A M [arr] Metal with fine mesh eyes | Very Hoo ype Key: : VY Limit Bis = Min Middle term Bis = Med Represents Maximum = Max Represents the number of components = X- oo ha Metal with mesh eyes min fis = FM elongated foil fis = EE representing an ellipse - EL ] representing glass fibres. = FG fas Explosion has high porosity Pads One of the advantages of the invention is that the pads have 1 strong The versatility of the Cari dal enables it to perform efficiently as a dispersion type arrestor for confined blasts; Without removing their effectiveness to act also as inhibitors of the deflecting variety to change the direction of the lateral forces of unconfined explosions. For the purposes of this stratification, it must have a porosity within the range of the pads of the invention. the felts; It is preferable for the porosity to be around 1 to 794 . And as specified in Table 286 vo : 7995 to 1 The stratification of the invention provides another benefit Pads The unique open lattice structure of the pads than the working efficiency of the Pads; Which enables the felts, in the form of a high internal surface area, to ignite without interfering with its capabilities to prevent explosion. Felts (al ga) as stands formerly have specific internal surface areas close to 1 such as those shown in Table 2808 #0 of 78 square feet per cubic foot; Which actually qualifies them as ignition fluids for all fuel class pads or flammable vapors. For the purposes of this invention; The felts. square feet per cubic foot YO to have a specific internal surface area of at least and in the practical application of the invention; It is possible to reach qualitative interior surface areas of square feet per cubic foot; Although for most practical purposes the FY is higher than ve such high spaces are not necessary.

The anti-blast pads may be easily placed on the structures; by screws ¢ pins; Adhesives ; and the like. And when placed in the correct position; The invention has widespread applicability for the protection of structures against explosions. Applications in homes and commercial buildings include covering the walls of garages; furnace rooms; Or other platforms in which fuel tanks or any other explosive materials are placed. and in cars; The firewall between the engine room and the passenger compartment may be covered with anti-explosion Pads. and for the purposes of combating terrorism; The walls of aircraft baggage compartments may easily be covered with the product of this invention; This is to contain and dampen the vibration and reflux caused by the bomb and to prevent the destruction that may occur to the control devices and structural elements 0 the vital structural elements of the aircraft. The material may be made into portable shields for use by policemen and firefighters when exposed to the threat of bomb blasts. The following example describes a particular application that explains the invention but should not be considered as limiting the scope of the invention. Example -: 1 Vo The layered pads with the structural shape shown in Figure 1 were tested in drawings to determine their efficiency in protecting walls of concrete blocks 6 feet long, 1 feet high, and 116 meters thick from blasting. The tests were conducted underground in a high energy containment bunker. Each of the diaphragm pads tested was xp nad 2 feet in length and . The material used ai all the Pads was 2,5808090 meters (1 millimeter) of uniquely cut sheets of alloy steel foil and as used; The material spread either in the form of an elongated metal mesh; Or as polygons ellipses. The ellipses were tao, + FAYO in diameter + 0.0056 lbs in weight + 7948 in porosity. The pads consisted of three layers of elliptical shapes, and four layers of stretched and unstretched metal foil. (Some tests were done with the four-layer foil in the stretched image and some in the unstretched image). The unstretched layers sneezed my cradle.”

-and 1- better performance by about 770 than the unstretched. The whole set was bound up between two layers of aluminum sieve size VT mesh; In the following composition: a layer of aluminum sieve size 11 mesh. Layer 8,506,060 meters of expanded (or unstretched) foil 6,5565601 meters ABE, expanded (or not) stretched) 07976 m diameter layer of ellipse of 1 m stretched (or unstretched) foil layer 6.0060601 0 stretched (0 unstretched) foil. Layer of 07475 ft Diameter Ellipse of 00000 Meters of 01 Elongated Foil Layer of 506060601 Meters of Elongated Foil (or Unstretched) Layer of 1074759 Meters of Diameter of ellipsoids of 00009 Meters of Elongated Foil. Layer oe ee is a stretched (or unstretched) foil meter. Vo layer of aluminum sieve, size 11 mesh (Type 0). Tests were conducted to determine the estimation of the measured distance achieved by the tested 5° blocking pad. The quantitative damage from the blast was calibrated by means of a relationship between the 'overpressure' (Ja) per square inch ¢ (psig) and the 'measured distance' (the ratio of the distance (in feet) the explosive charge is away from an object to the cube root of the material's weight Explosive charge (J); ft / (Td) The lower the distance measured in a given lad, the better the protection. The overpressure is proportional to the extent of the damage caused by the explosion. (See Kuchta, J.; Handbook Investigation of Fire and Explosion Incidents in the Chemical, Metallurgical and Fuel Industries USA Mine Bulletin No. 186 M50 Bureau of Mines Bulletin 17.5 Yo Tests were conducted by detonating a specified charge of the explosive asa ou C4 at a specified distance from the walls of a concrete block of thickness (+m ¢) with and without the presence of loo

— \ _ test between the wall and the explosive; Determine the measured distance at which blocker protection is available. The test showed that; When detonating o, YA a pound of plastic explosive 04 (equivalent to Yo, + a pound of TNT) at a distance of © inches from a 0 0.19 meter thick concrete LBS wall the wall cracks 0 However, when the fluid Pads of this invention are placed between the blast and the wall, no noticeable crack or damage occurs, and this enables the Aten to a measured distance of 17 ft / TT dda, and then the pad is shown The repellent Pad has the following characteristics: - Weight Tad / Jd, Y, ¥E 1 because Ee has less porosity | 8Azizal SaudiTerg>#g Measured Distance (Protection From (Jai) | 7" ft / PTY day) The previous test and characteristics provide the basis for the following interpretations:-

01 \= a concrete block wall with a thickness of .,0 mm Laie whose overpressure of explosion exceeds 1 psi will be shattered. At a measured distance of 1.7 ft/Th the excess pressure of the explosion is 1,001 psi. And accordingly; It turns out that the fluid pads of this invention completely absorb all the force of the explosion. Reduced overpressure from 0001 to Y psi.

00?- Although the fluid pads of this invention are completely lighter in weight than most modern al galls; They have a lower measured distance and greater overpressure dispersion than modern al gallons. *- The measured distance of 17 ft/lb “””” is within the range of 1 =, Yo ft/lb “”” provided by steel reinforced concrete. Tancreto ¢ C Tancreto, I. “Reinforced concrete in

“Ye. Blast Reinforced Buildings” © chapter » page at You ¢ Facility Design Considerations for All Chemicals and Explosives 3 edited by Rose. Scott with Jd. Lumney; American Chemical Society Symposium Series No. 46 187 :7

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Design Considerations for Toxic Chemical and Explosive Facilities, R. Scott and L.

Loemeny, Eds., ACS Symposium Series 345, American Chemical Society, 1987. Furthermore, tests show that the sealing pads of this invention can provide an unreinforced concrete block wall with destruction resistance equivalent to a steel-reinforced AS 0 concrete wall. A;- The measured distance of 1.7 ft/lb provides protection equivalent to that protecting an ABS concrete wall from the blast effects of a Yeo pound of TNT at Yeo ft. This is one of the requirements for buildings that contain explosives. R . strelo with &baker; Strehlow, R. and Baker;w. 'Description and Evaluation of Flash Eruptions'; ade Progress in Energy and Combustion Science Part ¥¢ p.a.b. Although the preferred applications of the invention have been described in this invention in detail; It would be understandable to those skilled in the field that changes can be made without deviating from the content of the invention. No

Claims (1)

- 1 A —- Elements of Protection 1-1 Lightweight Anti-Blast Layered Pads to protect against the devastating impact Y of the blast; Said Pads have a porosity in the range of 80 to 7450 and an 'inside specific surface area' of greater than 750 square feet per cubic foot; and comprising a first plate £ of slitting foil ¢ and a second plate of foil slit at a distance from said first plate; And an inner core layer of air-permeable material. 1 "- Explosion proof Pads of protection element No. 1 wherein said inner core Y of the air permeable material is at least 1 inch thick. 1 1 Explosion proof Pad 5 of protection element No. 11, where the mentioned first and second Y-sheets have been extended to produce expanded metal grids. -magnesium alloy ,. support Wherein the 1 explosion-proof foil sheets of protection element No. 1 Y-Slotted Pads mentioned have thicknesses in the range from about 0748 to 1 millimeter. \ 1 - The anti-explosion pad 5 of protection element Protection No. 6 “where the Y sheets of the first and second mentioned expanded metal mesh have a thickness ranging from about ? to a yen of a millimeter in its elongated form. 1 7”- anti-peated GL ad Pads Protection No. 1; Wherein the aforementioned inner core, Y of the air-permeable material, comprises a group of spherical bodies formed from the elongated metallic lattice 3. —A 1 Explosion-proof Pads of Protection No. 1 » where said inner core Y of the air permeable material comprises an array of ellipses formed from expanded metal lattice. yao mentioned Pads where pad 1) Explosion proof Pad 5 of protection element 4-1 is held between front and back covers; Said front cover incorporates 0 air permeable v. anti-explosion protection element No. 4; Where the front cover includes Felt Pads 0-1 on a woven sieve. Layered lightweight anti-blast protection against destructive impact Pads Pad 11-1 to 7960 and the Av area mentioned has a porosity in the range of Pads for blasting; and the pad is Y square feet per cubic foot; and its constituent layers bonded YOu an inner surface of higher quality than v together to form the unified structure containing: 4 (a) first sheet of expanded metal mesh made of magnesium alloy foil; magnesium alloy 1 (b) a second sheet of expanded metal mesh made of alloy foil; and magnesium alloy A (c) a second blastproof layer comprising at least one sheet of lattice 9 spaced from an elongated metal magnesium alloy of magnesium alloy 1 first blastproof layer. 1 (D) An air-permeable inner core layer separating the aforementioned first and second plates; VY and the aforementioned inner core layer includes solids in the form of an ellipse y. 0.128.0 alloy Vo, where Alloy 11 Explosion-proof Wrap of Protection Element Pads 1 -1 0.178 mentioned has a thickness in the range of about magnesium alloy Y 1 mm. to ¥ , where the expanded metal mesh 11 anti-explosion of the protective element Pads VY is 1 mm in its extended form. A mentioned has a thickness of about ? to Hoo L 1 6- Lightweight anti-explosion layered Pads to protect against the devastating effect Y of the explosion; Said Pads have a porosity in the range Av to 7900 and an internal specific surface area y higher than YOu square feet per cubic foot; And its constituent layers are; - Linked together to form a unified structure that contains: 0 (a) The front cover layer is composed of an air-permeable material. 1 (b) a first blastproof layer comprising at least two sheets of expanded steel mesh 71 of magnesium alloy in contact with each other and in proximity to said front cover layer A; 4(c) A second blastproof layer comprising at least one sheet of elongated metal lattice of magnesium alloy placed at a distance from the first blastproof layer 11. VY (d) an air-permeable inner core layer separating the aforementioned first and second explosion-proof layers yy; It includes the aforementioned inner core layer on the objects that are on <1> in the form of an ellipse embedded in it, which are made of the extended metal mesh of the magnesium alloy, Co. .magnesium alloy \o 4 (e) back cover layer bonded and joint with said front cover layer to provide uniform 7 L composition; and YA (f) an air-permeable Al inner core layer separating said second blast-proof layer from said back-covering layer; Said inner core layer includes YS ellipsoids fixed in it made of elongated steel mesh of magnesium alloy l-magnesium alloy -1 1 method of protecting structure against explosive blasting effect; Comprising the insertion of a 5 ¥ layered anti-blast pad between said structure and said explosive material and that 5 ¥ pad having a porosity in the range from 80 to 748 and an internal specific surface distance greater than YOu square feet per cubic foot; It includes an initial sheet of slotted foil; ° and a second sheet of foil slotted at a distance from said first sheet; And 1 inner core layer of breathable material. noo yy 1 - Claim No. Vo method; Where said inner core of the permeable material is at least Y of thickness YO 0.0 m. -11! Method of protection element No. V0, where the first and second mentioned plates, Y, are extended to produce expanded metal grilles. VA 1 Claim 06 method; Where the aforementioned expanded metal mesh is made of the metal foil of the magnesium alloy, Y.magnesium alloy. 1 4- Claim 18 method; Wherein, the metallic foil of said magnesium alloy Y has a thickness in the range of about 0.0778 to 1 millimeter. -0-1 claim method 17; Wherein the mentioned elongated gastric reticulum has a thickness of Y about A JY millimeters in its elongated form. -71 1 method of protection element V0 - where the said inner core of the permeable substance of sell includes a group of semi-spherical bodies formed from the elongated metal grid. YY 1 protection element method VO; Where the aforementioned inner core of the air-permeable material, Y comprises a set of ellipse-shaped solids formed from the metal and elongated lattice. —YY 1 protection element method Vo; Where the aforementioned Pads are sandwiched between the front and back Y covers; Said front cover includes breathable material. 1 *- claim method 77 Where the aforementioned front cover includes a woven sieve 7. huh”