Patent Publication Number: US-9417044-B1

Title: Explosives storage system

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a divisional application of U.S. patent application Ser. No. 14/169,587 filed Jan. 31, 2014 which further claims the benefit of U.S. Provisional Application No. 61/760,546, filed Feb. 4, 2013, both of which are hereby incorporated in their entirety by reference and the benefits of each is hereby claimed. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates generally to a container with a lid. More particularly, the invention relates to a system for storing explosives. 
     2. Description of the Related Art 
     Unexploded and abandoned ordnance, more broadly known as Explosive Remnants of War (ERW), is a global problem with a broad range of contributing factors. ERW can be an issue in any country or region in which an armed conflict has occurred on its soil. 
     Improvised containers do not necessarily provide adequate protection to the populace from ERW, nor do they protect the ERW from further deterioration from the elements. On the other hand, military grade storage devices and facilities can be expensive and are not feasible, especially in developing countries. 
     SUMMARY OF THE INVENTION 
     In accordance with one embodiment, an explosives storage system is described including: a substantially cylindrical container having an opening extending from a top end of the container along a central axis of the container, a sidewall formed between an outer perimeter of the container and an inner perimeter of the opening, and a base portion formed at a bottom end of the container to enclose a bottom of the opening, the bottom of the opening having a hemispherical shape; and a lid removably disposed on the top end of the container having a through-hole aligned substantially over the opening of the container. 
     In accordance with another embodiment, a method for manufacturing an explosives storage container is described, the method including: stacking a plurality of tires one on top of another; filling the plurality of tires with a cement and fiber mixture to form a cylindrical sidewall of the container surrounding a central opening; and creating a bottom layer of the container with the cement and fiber mixture, the bottom layer having a hemispherical shape on an inner side that forms a hemispherical termination of the opening. 
     Embodiments in accordance with the invention are best understood by reference to the following detailed description when read in conjunction with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  illustrates a perspective view of an exemplary explosives storage system in accordance with one embodiment. 
         FIG. 2A  illustrates a side sectional view of the explosives storage system of  FIG. 1  in accordance with one embodiment. 
         FIG. 2B  illustrates a top view of the explosives storage system of  FIG. 1  in accordance with one embodiment. 
         FIG. 2C  illustrates a top view of the explosives storage system of  FIG. 1  with a reinforcing structure in accordance with another embodiment. 
         FIGS. 3A-3C  illustrate a method of construction of an exemplary container for the explosives storage system of  FIG. 1  by utilizing a tire as reinforcement material in accordance with one embodiment. 
         FIG. 4  illustrates three tires stacked on top of one another to be used for reinforcement in accordance with one embodiment. 
         FIGS. 5-6  illustrate a method of construction of an exemplary container for the explosives storage system of  FIG. 1  using basket-like woven reinforcement in accordance with one embodiment. 
         FIG. 7  illustrates an exemplary lid of the explosive storage system of  FIG. 1  including a reinforcing structure, flexible covering, and a thin external finish in accordance with one embodiment. 
     
    
    
     Embodiments in accordance with the present invention are further described herein with reference to the drawings. 
     DETAILED DESCRIPTION OF THE INVENTION 
     A system that provides safe and secure storage of explosives is described herein. According to the embodiments of the present disclosure, the system for storing explosives is scalable and may be constructed using readily available materials at little to no cost. The system may also provide a suitable level of security to prevent theft of the stored explosives. As used herein, the term “explosives” refers to any device that may explode or detonate, such as bombs, improvised explosive devices (IEDs), or ERW. 
     In an event of unintended detonation of the explosives, the system should stop all ordnance-produced primary fragmentation (i.e., shrapnel from the ordnance itself), while eliminating or creating minimal secondary fragmentation from the storage system itself. Accordingly, the storage system described according to the embodiments of the present disclosure is directed to a thick, reinforced structure, in which the explosion is vented out the top of the structure. Thus, substantial explosive force is directed upward and away from surrounding personnel, while providing a way to contain the fragmentation within the structure. 
     A person having ordinary skill in the art would understand that explosive reactions will exploit any weakness in any material by taking a path of least resistance. Most blast protection and mitigation structures overcome this limitation by using very thick and very strong building materials. However, in keeping with the spirit of the embodiments of the present invention, low cost, abundantly available materials are utilized instead. 
     Accordingly, a cylindrical structure is utilized as the container and a hemispherical shape at the internal base of the container allows for the force from the explosion to take the path of least resistance, up and out, without having to turn around in any corners. That is, the inside of the container has substantially no corners. 
     In this way the explosive storage system is adapted to redirect the thermal effects and blast overpressure wave away from the population and mitigate its effects to a K-Factor of 24. A K-Factor of 24 or K-24 (31 feet or 9 meters) is the minimum distance allowed between an individual and a one pound (1 lb.) TNT equivalent explosive detonation without receiving life threatening or disabling injuries, such as lung or ear drum ruptures. Accordingly, a system for minimizing or stopping the ordnance-produced primary and secondary fragmentation is described by implementing a simple, scalable, design and construction methodology that utilizes readily available, sustainable, and reused materials. 
       FIG. 1  shows a perspective view of an explosives storage system  100  which includes a container  102  and a lid  106 . Container  102  has a cylindrical shaped body and has a round opening  104  at a top portion of container  102  that extends downward along a central axis of container  102 . In the present embodiment, the bottom of opening  104  terminates in a hemispherical shape  108  in order to minimize corners or edges. Accordingly, if ordnance detonated inside opening  104  of container  102 , fragmentation from the explosive will take the path of least resistance and exit upward, and out of container  102 . 
     In one embodiment, container  102  is covered with lid  106 . Lid  106  has a through-hole  110 , such as a round opening. In one embodiment, lid  106  is sized to be placed on top of container  102  and to cover the top of container  102  such that through-hole  110  is aligned over at least a portion of opening  104 . In some embodiments, latch devices  112  are formed in or attached to container  102  and lid  106  to enable explosives storage system  100  to be secured, such as by locking. 
       FIG. 2A  illustrates a side sectional view of explosives storage system  100  showing container  102  having opening  104  with hemispherical shape  108 , and lid  106 . In one embodiment container  102  has a continuous sidewall  200  made of, for example, cement with reinforcement fibers, and having a thickness  202  that is suitable to withstand an explosive blast. Container  102  further has a base portion  204 , made of, for example, cement with reinforcement fibers, and having a suitable thickness  206 . In one embodiment, sidewall  200  surrounds opening  104  to form a cylindrical cavity shape with a substantially smooth inner wall. Base portion  204  is formed in a hemispherical shape so that as the inner perimeter wall formed by sidewall  200  terminates in base portion  204 , the bottom of opening  104  is terminated in hemispherical shape  108 . In one embodiment, the hemispherical shape of the inner side of base portion  204  is substantially smooth. In some embodiments, latch devices  112  can be formed in or attached to container  102  and lid  106  to allow lid  106  to be secured to container  102 . 
       FIG. 2B  illustrates a top view of explosives storage system  100  showing container  102  covered with lid  106  in accordance with one embodiment. As earlier described, in one embodiment, lid  106  has a through-hole  110  (i.e., an opening) that is approximately the same size as opening  104  of container  102  to allow venting from container  102  when explosives detonate. Accordingly, an explosive device may be placed in container  102  and covered with lid  106  to contain any fragmentation from the blast. 
       FIG. 2C  illustrates a top view of explosives storage system  100  showing container  102  covered with lid  106  in which through-hole  110  is covered with a reinforcing structure  208 , such as a lattice of metal rods or webbing, in accordance with one embodiment. Reinforcing structure  208  serves to prevent entrance of outside elements, such as people, animals, or debris, and yet is spaced and/or flexible enough to allow a detonation force to escape upward from container  102 . In some embodiments, see for example,  FIG. 7 , a flexible covering such as a tarp material can be placed over through-hole  110  to prevent entrance of elements such as water or debris. 
     As earlier described, in one embodiment, lid  106  has through-hole  110  (i.e., an opening) that is approximately the same size as opening  104  of container  102  to allow venting from container  102  when explosives detonate. Accordingly, an explosive device may be placed in container  102  and covered with lid  106  to contain any fragmentation from a blast. In one embodiment, latch devices  112  when secured assist in containing a detonation in container  102 . 
     In some embodiments, container  102  may be made of a thick metal and/or reinforced building material in which an explosion is vented out of the top of container  102 . In various embodiments in accordance with the invention, container  102  can be made of various materials that may be abundantly available and low cost. In some embodiments, container  102  is first reinforced with fiber material. In some embodiments, lid  106  is made of materials similar to container  102 . In alternate embodiments, lid  106  can be made of materials different from container  102 . 
     According to an example embodiment, container  102  can be made of a mixture of cement and fiber reinforcement material. In more detail, a ratio of one-half portion (e.g., one-half of a bucket) of cement is added to one portion of fiber and dry mixed together, according to an example embodiment. Then one portion of soil is added to the cement and fiber mixture, and further dry mixed together. Next, one-half portion of sand is added to the cement, soil, and fiber mixture, and dry mixed again. Once the dry mixing is performing, the fibers are completely coated or “dusted” in the binding matrix, and water is gradually added in small amounts until the desired consistency of the mixture is obtained. 
     In some embodiments, the fiber can be one or more of natural fibers and/or raw fibers such as, by way of example and not of limitation, S bagasse (sugar cane pulp), phormium (New Zealand flax), Indian hemp (dogbane), papaya, reed fiber, ramie (China grass cloth), sisal (agave), coir, palm fiber, bamboo fiber, umbrella plant, milkweed, pina, abaca, cotton, kapok, bast fibers, nettles, esparto, bowstring hemp, jute, kenaf, henequen, hemp, flex, hoovine, elephant grass, yucca, water reed, plantain, musamba, wood fiber (kraft pulp), maguey, lechuguilla, banana leaf, and guaney. 
     In some embodiments, tires (e.g., truck tires) may be utilized as reinforcements for the container.  FIGS. 3A-3B  show the tire being packed with the mixture created as described above. In some embodiments, the tires can be stacked, one on top of another, for example, up to three or four tires high, as shown in  FIG. 4 . A center portion of the packed tires can have an opening and the hemispherical bottom portion can be formed as shown in  FIG. 3C . 
     Alternatively, in some embodiments, vertical stabilizers can be utilized and woven in a basket-like manner with horizontal stabilizers to create a framework, or reinforcement for the container. For example, substantially straight vertical stabilizers such as bamboo can be driven directly into the ground eight to 12″ (25.4 cm) as shown in  FIG. 5 . The vertical and horizontal stabilizers can also be comprised of other abundantly available materials such as plastic bags, sliced open plastic bottles, and sliced tires. 
     In some embodiments, the base of the container can be made first, and the vertical stabilizers can be driven directly into the outer edges of the base. Once the vertical stabilizers are set in place, horizontal stabilizer material is woven into the vertical stabilizers to form a basket-like structure as shown in  FIG. 5 . The cement and fiber mixture is used to fill in the space between the woven basket and the inner diameter to create the cylindrical sidewalls of the container as shown in  FIG. 6 . 
     Once the cement and fiber mixture is cured, the inner diameter mold can be removed and the internal hemispheric bottom portion is created. As described earlier, the hemispheric bottom portion redirects the thermal effects and blast wave of a detonation vertically upwards. 
     According to an embodiment, lid  106  for container  102  is constructed of approximately 3″ of the cement and fiber mixture. Lid  106  has a through-hole  110  at the center that is approximately the same size as opening  104  of container  102 , i.e., the inner diameter of through-hole  110  is approximately 20″-24″ (50.8 cm) to allow the detonation to vent directly up and out of container  102 , and away from the surrounding area. 
     In one embodiment, once the cement and fiber mixture of container  102  and lid  106  cures, an external finish is applied to the surface to further reduce the effects of a detonation, and allow for painting the surface to protect container  102  and lid  106  from elements. A thin external finish can also applied covering the venting hole of the lid as shown in  FIG. 7 . As further shown in  FIG. 7 , in one embodiment, lid  106  can include a reinforcing structure  702 , a flexible covering,  704 , and a thin finish  706 . 
     Although various materials and fibers have been described in fabricating exemplary embodiments in accordance with the invention other materials can also be used. Naturally occurring, discontinuous short cellulose fibers are widely used in Fiber Reinforced Concrete (FRC) all over the world. Termed natural fiber reinforced concrete (NFRC), its applications are numerous and include modern synthetically reinforced building materials. A myriad of natural reinforcing materials can be obtained at little cost, or for free, as agricultural byproducts using locally available manpower and technical expertise. Fibers, such as hemp and jute, are often used in the manufacture of low fiber content building materials and are typically referred to as unprocessed natural fibers (UNF). However, as the fiber content is increased, the material strength increases. 
     A variety of fiber materials other than steel, glass, or natural fibers have been developed and used to reinforce building materials, most commonly concrete. These fibers are categorized as synthetic fibers and are used in cement products generally termed SNFRC. Some of these fibers have little reported research while others, such as polypropylene, are often found in commercial applications and have been tested extensively. Synthetic fibers can increase the concrete composite&#39;s ductility and impact resistance significantly. Many synthetic materials can be found throughout the world as waste, such as plastic bags, water bottles, and discarded polypropylene rope that has reached the end of its service life. Any of these or other man-made material with acceptable tensile strength could be used as a substitute or addition to synthetic fibers. Variations of synthetic materials might be available as waste products such as any length of discarded rope, Polyethylene terephthalate (PET) from plastic bottles, or any readily shred-able plastic similar to PET or Polypropylene (PP). 
     Accordingly, this disclosure provides exemplary embodiments of the present invention. The scope of the present invention is not limited by these exemplary embodiments. Numerous variations, whether explicitly provided for by the specification or implied by the specification or not, may be implemented by one of skill in the art in view of this disclosure.