MXPA97008888A - Member of computing structural reinforcement - Google Patents

Abstract

A reinforced structural member has a "W" shaped reinforcing member that carries an expandable thermal resin based material. The "W" resin reinforcing member is placed in the channel of a hollow structural member above a transverse pin that fits through the groove of the reinforcing member. The structural member is heated to expand the resin-based material that holds the reinforcing member in place, thereby significantly reinforcing the structural member.

Description

"MEMBER OF COMPOSITE STRUCTURAL REINFORCEMENT" TECHNICAL FIELD OF THE INVENTION The present invention relates generally to automotive body structural members and, more specifically, relates to reinforcing members to increase the strength of the structural members of the automobile body.

BACKGROUND OF THE INVENTION In a number of design applications, particularly in the automotive industry, it is essential to provide structural members that are lightweight and yet have high strength characteristics. A number of exotic metal alloys and the like have been proposed by others in the past to be used to form high strength structural members; however, in some applications, including the automotive industry, the cost of these alloys is typically prohibitive. Accordingly, there is a need for structural reinforcement members that are lightweight, and inexpensive and that can be used to complement existing design structures. There is a considerable aggregate of prior art transactions with the reinforcement of structural components of motor vehicles. In the North American Patent Number 4,901,500 called "Light-Weight Composite Beam", a reinforcing beam for a vehicle door is disclosed which comprises a metal member in the form of an open channel having a longitudinal cavity that is filled with a material based on thermosetting or thermoplastic resin. In US Patent Number 4,908,930 entitled "Method of Making a Torsion Bar", a hollow torsion bar reinforced with a mixture of resin with filler or filler material is described. The tube is cut to the desired length and loaded with a resin-based material. In U.S. Patent No. 4,751,249 entitled "Reinforcement Insert for a Structural Member and Method of Making and Using the Same", a premolded reinforcement insert is provided for structural members that is formed of a plurality of granules containing a thermosetting resin and an agent inflator The pre-molded part expands and is cured in place in the structural member. Also, in US Pat. No. 4,978,562 entitled "Composite Tubular Door Beam Reinforced with a Syntactic Foam Core Localized in the Midspan of the Tube", a composite door beam having a resin base core occupying not more than a third is discarded. part of the drilling of a metal tube. In the co-pending US Patent Application Serial No. 245,798 filed May 19, 1994, entitled "Composite Laminate Beam for Automotive Body Construction", a hollow laminated beam characterized by a high mass-stiffness ratio and having an external portion is disclosed. It is separated from an inner tube by a thin layer of structural foam. Although in some applications there are advantages to these reinforcement techniques from the previous branch, there is a need to provide a reinforcement for the rail sections that increases the rail resistance, particularly at stress points, in a way that is not only costly. low but also easily adapts to the mass production assembly. In addition, cyanoguanidine is known to be a latent curing agent commonly used for foamed epoxy polymers. The material most frequently used has the nominal particle size of approximately 80 microns. For greater reactivity, micronized versions are sometimes used. 90 percent of particles less than 30 microns. In the prior art, the conventional use of curing agents can cause the "combustion" of the foamed polymer. This is because the heat of the exothermic healing reaction does not dissipate easily. However, this solution is not practical when the furnace temperature is pre-graduated for other conditions, that is, for paint curing and similar conditions.COMPENDIUM OF THE INVENTION In one aspect, the present invention provides a reinforced structural member. The reinforced structural member has a longitudinal cavity in which a reinforcing member is placed. The reinforcing member includes a slot through which a pin or other coupling means extends. The pin is secured on the opposite side walls of the structural member. The sides of the reinforcing member are open and the interior of the reinforcing member is filled with a resin-based material. The reinforced structural member is assembled securing the pin in position and then dropping the reinforcing member that is filled with the resin-based material above the pin. The open sides of the reinforcing member and the resin-based material therein are the adjacent side walls of the structural member, the pin passing through the open slot of the reinforcing member. The structural member, which may comprise a motor vehicle rail is moved through a priming furnace after which the resin-based material expands and adheres to the side walls of the structural member, so as to form a intense bond with the internal walls of the structural member. The expanded resin-based material effectively creates a single unitary structure comprising the reinforcing member, the expanded resin and the structural member. In another aspect, the openings in the reinforcing member adjacent to the bottom of the structural member allow the resin to expand through the openings and join yet another surface of the structural member in order to provide even greater bonding of the limb member. reinforcement in the structural member. In still another aspect, the present invention provides a novel reinforcing material based on epoxy resin, containing epoxy resin, an elastomer, a filler or filler, fuming silica, high-strength glass spheres together with a curing agent, an accelerator and a puffing agent.

In the present invention, the overall strength of the structural member is significantly increased, reducing cracks at the stress points where the reinforcing member is placed.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a perspective view of a portion of reinforced rail member in accordance with the present invention. Figure 2 is a side elevation view of the rail member of Figure 1, partially broken away to illustrate the placement of the reinforcing member and the transverse pin. Figure 3 is a perspective view of the structural reinforcement carrying member before being inserted into the hollow structural member of Figures 1 and 2. Figure 4 is a cross section through lines 4-4 of Figure 3. Figure 5 is a perspective view of the hollow structural member with the transverse reinforcing pin prior to the insertion of the reinforcing member.

Figure 6 is a side elevational view of a partially broken and recessed hollow frame section according to the present invention in another embodiment. Figure 7 is a cross-section of reinforcement member of Figure 6 on the line 7-7. Figure 8 is a perspective view of the reinforcement member of Figure 3, without the resin-based core. Figure 9 is an elevation view of a reinforcement member in another configuration for use in the present invention. Figure 10 is an elevation view of a reinforcing member and retaining pin in another configuration for use in the present invention. Figure 11 is a plan view of the structure shown in Figure 1, but with the core based on resin removed. Figure 12 is an elevation view of a reinforcing member in another configuration for use in the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to Figure 1 of the drawings, a reinforced structure 18 having a hollow structural member 20 with an upper or closing plate 22 (shown in silhouette) is seen. The structural member 20 has opposite sidewalls 24 and 26 and a floor or bottom surface 28 and is therefore of the nature of a channel-shaped member. A rod or pin 30 extends between opposite side walls 24 and 26 as best shown in Figure 5 of the drawings. The pin 30 serves as a shock absorbing accessory and as a retaining member for the reinforcing member 32. The reinforcing member 32 is positioned within the longitudinal channel or cavity 34 of the hollow structural member 20 and has a carrier portion 33 (best shown in Figure 8) that serves as a carrier or container for the reinforcing / bonding material 36. based on resin. In Figure 2 of the drawings, the side wall 24 is shown partly broken to reveal the reinforcing member 32 and the end of the pin 30. The hollow structural member 20 is preferably formed of metal, for example of steel, and is especially preferred a rail of a motor vehicle. Accordingly, in the especially preferred embodiment, the reinforced structural member 18 is a car rail or beam.

Referring now to Figures 3, 4 and 8 of the drawings, the carrier 33 has external side walls 38 and 48, internal side walls 42 and 44, lower walls 46 and 48 and a connecting wall 50 in such a way as to define two channel-shaped cavities or reservoirs 52 and 54. As best shown in Figures 4 and 8, these walls define a "c" shaped resin receiving cavity 56. In this way, the resin-based reinforcement / bonding material 36 forms a "c" -shaped resin body structure or core 58. It will be understood that a number of geometries may be suitable for use as the carrier 33 and that the "w" design or configuration, even if it is preferred, is only one of these configurations. For example, a corrugated configuration 70, as shown in Figure 9, or an inverted "u" shaped structure 72 as shown in Figure 10, which have an outer, resin-based material coating (i.e. , no external side walls) may be appropriate in a given application. It may also be appropriate to completely remove the carrier 33 and use a freestanding resin body 74 as shown in Figure 12. In general, it is sufficient that the reinforcing member 32 has a means for containing or supporting a reinforcing body based on of resin and a means for interconnecting with a positioning retention means in position such as the pin 30. Preferably, the carrier 33 will define one or more containment sites or reservoirs for the resin-based reinforcement / binding material. , while still having openings such that the resin-based reinforcement / bonding material can expand and bond with the side walls 24 and 26 of the hollow structural member. The thickness or thickness of the carrier 33 may vary, but typically it is between .025 and approximately .060. The dimensions of the reinforcing member 32 should closely coincide with the channel 34 so that there are at least some contact points between the carrier 33 and the side walls 24 and 26, but will not require the channel 34 to expand for insertion of the reinforcing member 32 during assembly. The pin 30 is preferably metal and as stated serves to retain the reinforcement member 32 in place by engagement with the groove 60 defined by the internal side walls 42, 44, and the connection wall 50 of the carrier 33. It is especially preferred that any clearance between the pin 30 and the slot 60 be sufficiently small such that the reinforcing member 32 does not move significantly even before the expansion of the resin-based reinforcement / bonding material 36. The composition of the resin-based reinforcement / bonding material 36 as well as the method of assembling the reinforced structural member 18 will be described more fully below. In still another embodiment of the present invention, now referring to reference to Figures 6 and 7 of the drawings, the reinforcing member 32 'is shown having a plurality of openings or channels 62 through which the material 36' flows at Resin base during expansion in the assembly process. This forms additional bonding regions 64 on the surface 28 'of the floor of the hollow structural member. By providing the openings 62 in this manner, additional bracing and reinforcing strength is obtained for the reinforced structure 18. In this embodiment, all other features of the reinforced structural member 18 are identical to those described in relation to the embodiment shown in Figures 1 to 5. A number of materials may be appropriate to be used to form the reinforcing / bonding material 36. resin base. The appropriate materials must have sufficient body when they are not cured or partially cured so that the material does not flow significantly out of the carrier 33 once it has formed and before it is inserted into the channel 34. Therefore,, it will be appreciated that the carrier 33 receives the resin-based reinforcement / bonding material 36 in a preparation step to form a unit that is subsequently dropped into the channel 34. In addition to having sufficient body, it is important that the material 36 resin-based reinforcement / bonding is permanently expanded to contact the sidewalls 24 and 26 (and the floor surface 28 in the embodiment shown in Figure 4 and Figure 7) and this permanent expansion provides the strength of desired compression. It is also important that the resin-based reinforcement / bonding material 36 adhere strongly to the internal surfaces of the carrier 33, as well as the side walls 24 and 26. The resin-based reinforcement / bonding material 36 should also be the sufficiently thermally stable in such a way that it does not degrade to the temperatures experienced in paint curing ovens and similar operations. The resin-based reinforcement / bonding material 36 should also be lightweight and inexpensive and, in general, should impart excellent mechanical strength to the reinforced structural member 18. More specifically, the resin-based reinforcement / bonding material 36 should have a density of about 560 grams per cubic centimeter to about 1040 grams per cubic centimeter before being fully cured and from about 400 grams per cubic centimeter to 720 grams per cubic centimeter. cubic centimeter once it has expanded completely into place. The compressive strength of the resin body 58 (after expansion and cure) should be at least 70.30 kilograms per square centimeter and more preferably approximately 105.45 kilograms per square centimeter or greater. The bond between the resin body 58 and the side walls 24 and 26, where the side walls 24 and 26 are made of steel, should be sufficient to maintain the strength of the metal bond / cure. This minimizes the separation of the resin body 58 from the side walls 24 and 26 as well as from the carrier 33. The cured resin body 58 must be able to withstand temperatures in excess of 232 ° C for short periods absent from any significant applied stress and temperatures up to about 80 ° C for long periods without exhibiting considerable heat induced distortion or segregation. The resin body 58 can be formed in place on the carrier 33 by closing the open side walls 39 and 41 of the carrier 33, and injecting or emptying a liquid or a paste such as a resin-based material therein. The material 36 can then be hardened in place by curing or cooling. Alternatively, the resin body 58 can be preformed and then inserted into the resin receiving cavity 56 which is defined by the carrier 33. A preferred material for use as a resin-based reinforcement / bonding material 36 includes a synthetic resin, a expandable self-foaming agent and a filling or loading material. All percentages herein are by weight unless otherwise indicated. In one embodiment, the synthetic resin comprises from about 45 percent to about 70 percent by weight and preferably from about 50 percent to about 60 percent by weight of the resin body 58. A cellular structure is especially preferred since it provides a low density and high strength material that is sturdy and yet light in weight. The self-foaming agent may comprise a chemical swelling agent such as azodicarbonamide or P, P'-oxybis (benzenesulfonyl hydrazide) comprising from about 0.1 percent to about 10 percent, and most preferably about .5 percent a about 2 weight percent of the body 58 of resin. In addition, in some applications, it may be preferable to use plastic microspheres which may be either thermosettable or thermoplastic and which are in their unexpanded state until the reinforcing structural member is heated to expand the material 36. It should be understood that the material 36 does not fully expand until after reinforcement 32 is in position on channel 34. When using blowing agents such as the self-foaming agent, comprise from about 0 percent to about 10 percent, and more preferably from about 1.5 percent to about 3 percent by weight of body 58 of resin. A number of fillers or fillers are suitable including glass or plastic microspheres, fuming silica, calcium carbonate, ground glass fiber and crushed glass strands. A filler or filler material comprises from about 20 percent to about 50 percent by weight and more preferably from about 25 percent to about 40 percent by weight of the resin body 58. Preferred synthetic resins for use in the present invention include thermosetting resins, such as epoxy resins on the one hand, vinyl ester resins, thermosetting polyester resins and urethane resins. The average molecular weight (number average) of the resin component is from about 1,000 to about 5,000,000. When the resin component of the material 36 is a thermosetting resin, various accelerators are included such as modified ureas or boron trichloride. A curing agent such as dicyandiamide is used to cure the resin. A functional amount of the accelerator is typically from about .1 percent to about 5 percent of the weight of the resin with a corresponding reduction in one of the three components: resin, self-foaming agent or filler or filler. Some thermoplastic materials may also be appropriate. An especially preferred composition for use as the material 36 and one comprising another aspect of the present invention, is an epoxy system of an uncured part which is provided in the form of a high viscosity "dough" which is placed in the carrier 33 as described above. With the epoxy mass of a preferred part, the uncured material 36 and therefore the reinforcing member 32 can be washed, phosphatized or otherwise treated with an alkaline or acidic solution without noticeable deterioration of the material 36. In this way the material 36 in this embodiment is resistant to acids and bases in its uncured state. Particularly in automotive applications, this feature allows the reinforcing member 32 to be inserted at an early stage in the production line. Accordingly, in a preferred embodiment, the material 36 contains in weight percent from about 30 percent to 70 percent epoxy resin, from about 0 percent to 20 percent elastomers such as polybutyl rubber, acrylonitrile butadiene rubber (ABR) or polyisoprene, from about 1 percent to 30 percent of a filler or filler such as calcium carbonate, fuming silica, high strength glass microspheres and from about 0 percent to 10 percent of the swelling agent such as azodicarbonamide or P, P '-oxibis (benzenesulfonyl hydrazide). In addition, the material 36 further includes from about 2 percent to 10 percent of the agent of the curing agent such as dicyandiamide or cyanoguanidine. It has been found that the size of the particulate curing agent is an important feature of the preferred formulation of material 36. Providing a pulverized or particulate curing agent where 40 percent of the particles are larger than 15 microns in diameter, which is completely mixed with the other constituents of the material 36, a uniform cure can be obtained without thermal degradation to the - temperatures experienced in car priming ovens. In other words, by using a one part epoxy resin containing mixtures of cyanoguanidine having a high coarse particle content, there is no "combustion" or reduced "combustion" levels inside the cured epoxy foam mass. Also preferably included is from about 0 percent to about 5 percent of the accelerator such as modified ureas or boron trichloride in the material 36. Approximately 0 percent to 10 percent carbon black can also be included. In the especially preferred embodiments, the material 36 includes from about 1 percent to 6 percent hydrophobic silica and about 18 to 27 high strength glass spheres ranging from about 20 microns to about 400 microns in diameter. High strength spheres should have a hardness (crush resistance) of at least 35.15 kilograms per square centimeter. Especially preferred epoxy resins are solid bisphenol A and solid bisphenol F including the liquid epoxy resin. One of these epoxy resins is sold as DGEBPA resins by The Peninsula Polymer Company. The especially preferred elastomer is acrylonitrile-butadiene rubber and is sold as NIPOL 1312 by The Zeon Company of Kentucky. A preferred filler or filler is calcium carbonate treated with stearic acid sold as WINNOFIL SPT by The Zeneca Company of Massachusetts. The preferred fuming silica is sold as CAB-O-SIL TS 720 by The Cabot Company of Illinois. The preferred high strength glass spheres are sold as B38 Glass Bubbles by The 3M Company of Minnesota. The curing agent, the healing elastomer and the especially preferred swelling agent are sold as Diciandimide G sold by SKW of Georgia, AMICURE UR (Air Products Company of Pennsylvania) and CELOGEN OT (Uniroyal Company of Connecticut), respectively. In the especially preferred embodiment, the (uncured) preparation material 36 must have a mass-like consistency. The material 36 can be prepared by conventional techniques such as mixing the various components together.

In the following table, a preferred formulation is indicated for the resin-based reinforcement / bonding material 36. It should be understood that this formulation is only preferred that other formulations are appropriate in a specific application.

TABLE I Percent by weight Epoxy Resin 50.45 Acrylonitrile Butadiene Rubber 4.33 Calcium Carbonate 5.81 Carbon Black 0.13 Fumed Silica 3.55 Heavy Duty Glass Sphere 22.40 Healing Agent 4.33 Accelerator 1.29 Inflator 0.71 For the assembly of the reinforced structural member 18 and now referring to Figures 1 and 3 of the drawings, the resin-based reinforcement / bonding material 36 is prepared and placed on the carrier 33 as described above. A number of reinforcement members 32 loaded at one time may be prepared and stored for future use. It should be understood that at the point of time when the reinforcement member 32 is to be dropped towards the channel 34, the material 36 The resin-based reinforcement / bonding is of high viscosity such that it is retained within the reinforcing member 32 but is still capable of expanding and fully healing or solidifying to form a rigid structure (resin body 58) in the channel 34. in combination with the carrier 33. The perforations are drilled through the side walls 24 and 26 and the pin 30 is inserted therein. It will be appreciated that the function of the pin 30 is to hold the reinforcement member 32 in place in the channel 34., and that other securing means such as buttons or the like which extend only partially from each of the opposite sidewalls 24 and 26 may be appropriate or desirable in any given application. Preferably, the pin 30 is welded in place in such a manner that it extends through the channel 34 as best shown in Figure 5 and provides strength to the structure 18. The reinforcing member 32 is allowed to fall into the channel 34. in such a manner that the pin 30 slides into the slot 60 to thereby secure the reinforcement member 32 in place (ie, the reinforcing member 32 is restricted in longitudinal movement along the channel 34). In the embodiment shown in Figure 1, the upper plate 22 is then placed on the hollow structural member 20 and is welded in place so that the channel 34 is completely closed. As the motor vehicle moves through the paint furnace, the resin-based reinforcement / bonding material 36 expands thermally to form the rigid resin body 58 which, as shown, holds the reinforcement member 32 in channel 34. In other words, once it has fully expanded and solidified or cured, reinforcing member 32, resin body 58 and opposite walls 24 and 26 form an integral mass of material that adds significant strength to the structural member 18 reinforced. Although the time and temperature can vary considerably depending on the selection of materials used to form the resin-based reinforcement / bonding material 36, with the preferred formulations noted in the above tables the material 36 must be heated to a sufficiently high temperature. , depending on the amount of the accelerator, the healing agent and the mass. The reinforced structure 18 has a number of advantages in relation to the structures of the prior art. By strategically positioning the reinforcement member 32 at the stress points, metal fatigue and cracking can be reduced without the use of thick metals to form the structural member. It is therefore preferred that the carrier 32 occupy less than half the volume of the structure 20, ie, of the cavity 34. It will also be appreciated that the preferred configuration of the carrier 33 results in the formation of a series (three in the preferred "w" -shaped design of "u" or column-like structures extending between the side walls 24 and 26. The resistance to the compression forces and the torque of the pin as shown in FIG. length of an axis through the side walls 24 and 26 and therefore, along the length of the columns, is significant. It will be appreciated that the carrier 33 acts as a container for the resin body 58 which maintains the body 58 against warping, cracking or exfoliation as well as acting as a handling mechanism. This is particularly important when the resin body 58 is the main load carrying unit. In turn, the resin body 58 stabilizes the carrier 33 in such a way that the carrier 33 does not buckle before the time the resin body 33 acts as a support structure. Although a specific embodiment of this invention has been shown and described herein, it will be understood that the invention is not limited thereto since many modifications can be made, particularly by those skilled in the art in view of this disclosure. It is therefore proposed that the present invention cover any of those modifications that fall within the true and spirit of the scope of this invention.

Claims (22)

R E I V I N D I C A C I O N E S:

1. A reinforced structural member comprising: a structural member defining a space; a reinforcing member placed in the space, the reinforcing member has a carrier portion and a thermally expanded portion, wherein the carrier portion is a carrier for the thermally expanded portion, the thermally expanded portion is bound to the structural member and the carrier portion; and a means for retaining the reinforcing member in the structural member.

2. The invention according to claim 1, wherein the carrier portion has at least one opening through which a portion of the thermally expanded portion extends, the extended portion of the thermally expanded portion is bound to the structural member. aforementioned.

The invention according to claim 1, wherein the portion of the carrier defines a slot and wherein the retaining means includes a projection fixed to the structural member and projecting into space, the projection being at least partially positioned in the slot for retaining the reinforcement member in that space.

4. The invention according to claim 1, wherein the thermally expanded portion is a resin-based material.

5. The invention according to claim 1, wherein the structural member is a section of metal rail, the portion of the carrier has a geometry that defines both a groove and at least one reservoir, the thermally expanded portion is a material based on resin placed in the reservoir, the retention means is a projection extending towards the space and which is fixed to the structural member, the projection extends towards the slot to hold the structural member in place.

6. The invention according to claim 5, wherein the portion of the carrier is a "w" -shaped sheet of metal having two reservoir portions, one of the reservoir portions being placed in a slot and the other of The spare portions are placed on the other side of the slot, the thermally expanded portion is placed in both of the tanks.

The invention according to claim 5, wherein the "w" metal sheet has a longitudinal axis that passes through both reservoirs and a transverse axis perpendicular to the longitudinal axis, and wherein the slot is a channel extending along the transverse axis, the structural member has opposite side walls, and the metal sheet in the form of "w" being placed in that space with the transverse axis extending from one of the opposite side walls to the other of the opposite side walls.

8. A reinforced structural member comprising: a steel rail having opposite side walls and defining a longitudinal channel, the longitudinal channel being along a longitudinal axis; placed in the channel, a resin support reinforcement member defining a cavity formed of metal placed in the channel, the resin support reinforcement member has at least one structure in the form of a column and at least one groove, the column-shaped structure has a column axis along the length of the column-shaped structure, with the axis of the column extending between the opposite side walls perpendicular to the longitudinal axis; a pin fixed to the steel rail and extending towards the slot; and - 2! a resin base core placed in a cavity defined by the resin support reinforcement member defining the cavity, a resin-based core being adhered to the side wall and the resin support reinforcement member defining the cavity.

9. The invention according to claim 8, wherein the resin base core is formed of a thermally expanded resin-based material.

The invention according to claim 8, wherein the resin support reinforcement member defining the cavity has a "u" shaped configuration that defines three columnar structures.

11. A reinforcement insert for reinforcing a hollow structural member, the insert comprising: a portion of the metal carrier defining a resin receiving space and a pin receiving groove; and a resin-based portion placed in the resin receiving space, the resin-based portion being less fully expanded and less completely cured.

12. The invention according to claim 11, wherein the portion of the metal carrier has the shape of a W.

13. A reinforcing structural member comprising: a structural member defining a space; a reinforcing member placed in that space, the reinforcing member consists essentially of an expanded resin base body thermally bonded to the structural member, the resin-based body further defining a groove; and means for retaining the reinforcing member in the structural member, the retaining means including means for engaging the groove.

The invention according to claim 13, wherein the retaining means is a pin secured to the structural member.

15. A method for reinforcing a structural member comprising the steps of: forming a metal carrier, the metal carrier defining a resin receiving space and a slot; applying a carrier-based expandable resin-based material in the resin receiving space; providing a hollow structural member having a longitudinal cavity and securing a pin to the hollow structural member in the cavity; place the metal carrier with the resin-based material therein in the cavity and with the pin passing through the slot; and expanding the resin-based material to bind the carrier to the structural member.

16. The invention according to claim 15, wherein the expandable resin-based material is thermally expanded and wherein the expansion step is carried out by heating the structural member.

17. A reinforcing rail for a motor vehicle comprising: a hollow rail section having an opposite side wall defining a longitudinal channel; a pin having one end fixed to a side wall and the other end fixed to the other side wall; a strip of metal in the form of "w" that defines two deposits and a groove; a core core of thermally expanded resin bonded to the metal carrier in the form of "w" in the tanks; the metal strip "w" is placed in the hollow rail section between the opposite side wall and is bound to the side walls by the resin base core; and the pin is in position in the slot.

18. The invention according to claim 18, wherein the rail has a bottom wall connecting the opposite side wall, and the metal strip in the form of "w", has at least one opening therethrough through which extends a portion of the resin-based core, the extended portion of the core being attached to the floor.

19. The invention according to claim 1, wherein the expanded portion contains epoxy resin, an elastomer, fumed silica, high strength glass microspheres, a swelling agent and a curing agent.

20. The invention according to claim 19, further comprising a filler or filler and an accelerator.

21. A composition for reinforcing structural members comprising: epoxy resin; an elastomer; fumed silica; high strength glass microspheres; a puffing agent; and a healing agent.

22. The invention according to claim 21, wherein the elastomer is an acrylonitrile-butadiene rubber.