WO2015045152A1

WO2015045152A1 - Dump body structure for dump truck

Info

Publication number: WO2015045152A1
Application number: PCT/JP2013/076538
Authority: WO
Inventors: 篤北口; 崇佐々木; 純池田
Original assignee: 日立建機株式会社
Priority date: 2013-09-30
Filing date: 2013-09-30
Publication date: 2015-04-02

Abstract

Stiffeners (26a-26i) are welded to a bottom plate (22a) which constitutes a part of the load carrying section (22) of a dump body (20). The intersection between a dump body rail (23) and the stiffener (26a) among the stiffeners (26a-26i), the stiffener (26a) being located on the front side, with respect to the vehicle body, of at least the bottom plate (22a), and the intersection between the dump body rail (23) and the stiffener (26f), where a hinge pin bracket (24) is located, are reinforced respectively by reinforcement members (28). As a result of this configuration, the portion where stress due to a load concentrates when the dump body is loaded can be effectively reinforced, and consequently, the dump body (20) can exhibit high strength and rigidity while an increase in the weight of the dump body (20) is minimized.

Description

Dump truck bed structure

The present invention relates to an ultra-large dump truck used in a large-scale civil engineering work site such as dam construction or in a mine, and more particularly, a structure of a loading platform (dump body) for directly loading crushed stones or earth and sand. It is about.

As a transport vehicle for earth and sand in large-scale civil engineering work such as dam construction and open-pit mining work in mines (mining), for example, as shown in Patent Document 1 below, the loading capacity exceeds several tens to 100 t. A very large dump truck is used. Such an ultra-large dump truck travels in a state where loads such as crushed stones and earth and sand are piled up on the loading platform (dump body). A large load is also applied to the front, rear, left and right directions.

Therefore, the entire loading platform is formed of a robust material such as a thick steel plate and is reinforced in various ways. For example, the loading platform (dump body) of Patent Document 2 below forms a container-shaped stacking portion from a bottom plate and a front plate made of steel plates, and left and right side plates, and the vertical position of each steel plate is positioned outside the stacking portion. The entire loading portion is reinforced by welding a plurality of steel reinforcing members so as to extend in the horizontal direction or the horizontal direction.

JP 2007-176269 A Special table 2013-526446 gazette

By the way, in the case of the structure in which the loading portion is reinforced by the steel reinforcing member as described above, if many reinforcing members are used in order to obtain sufficient strength and rigidity, the weight of the loading platform increases correspondingly. There's a problem. An increase in the weight of the loading platform should be avoided as much as possible because it causes a decrease in the allowable load mass, a deterioration in driving fuel consumption, and a decrease in tire life.

Accordingly, the present invention has been devised to solve these problems, and an object of the present invention is to provide a novel dump truck bed structure capable of exhibiting excellent strength and rigidity while suppressing an increase in weight. Is.

In order to solve the above-described problems, a first invention includes a container-like stacking portion located on a body frame of a dump truck, and a loading platform rail provided on the bottom plate side of the stacking portion so as to extend in the front-rear direction of the vehicle body. A dump truck comprising: a plurality of stiffeners provided on a bottom plate side of the stacking portion so as to intersect with the carrier rail; and a reinforcing member that reinforces the intersection between the stiffener and the carrier rail. It is a cargo bed structure.

As a result of detailed investigation and analysis of the load applied to each part of the load carrier having the conventional structure at the time of loading (full load), the inventors have found that the load of the load is applied to the intersection of the stiffener that reinforces the loading part and the carrier rail. It was found that (stress) was concentrated. Therefore, by reinforcing the portion where the load is concentrated with a reinforcing member as in the present invention, it is possible to exhibit excellent strength and rigidity while suppressing an increase in the weight of the loading platform.

According to a second invention, in the first invention, the intersection reinforced by the reinforcing member is an intersection between the cargo bed rail and a stiffener located on the vehicle body front side of the bottom plate. This is a cargo bed structure. As described above, as a result of detailed investigation and analysis of the load applied to each part of the load carrier with the conventional structure when loaded (full load), the load of the load is particularly at the intersection of the stiffener and load carrier rail located in the front row of the load part. It was found that a larger load (stress) was concentrated. Therefore, by providing a reinforcing member at a portion where the load is concentrated, it is possible to reinforce more effectively while suppressing an increase in the weight of the loading platform.

According to a third invention, in the first or second invention, the cargo bed rail includes a pair of rail members extending in parallel with each other, and the reinforcing member is provided at each intersection of the pair of rail members and the stiffener. A dump truck bed structure characterized by being provided. According to such a structure, it is possible to reliably reinforce only the portion where the load is concentrated while suppressing an increase in the weight of the loading platform.

According to a fourth invention, in the first to third inventions, the carrier rail and the stiffener are formed in a substantially rectangular cross section, and the intersection reinforced by the reinforcing member is arranged such that the carrier rail side is more than the stiffener. The dumping truck structure is characterized in that the reinforcing member has a vertical truss plate that is welded so as to be bridged obliquely between the side surface of the loading platform rail and the upper surface of the stiffener.

The present inventors analyzed the load applied to the intersection of the stiffener and the load carrier rail located on the front side of the load carrier having the conventional structure when loaded (full load). It was found that a large downward bending moment (stress) occurs at the intersection of the stiffener as a fulcrum when the outer stiffener bends downward. Therefore, the intersection is reinforced by attaching a reinforcing member made of a vertical truss plate that is welded so as to cross between the side of the cargo bed rail and the upper surface of the stiffener at an angle, and the stress concentrated on the portion ( Bending moment) can be dispersed and reinforced.

According to a fifth invention, in the fourth invention, the reinforcing member further includes a rail side contact plate welded to a side surface of the cargo bed rail, and a stiffener side contact plate welded to an upper surface of the stiffener, The vertical truss plate is welded between the rail side contact plate and the stiffener side contact plate. By welding the vertical truss plate through the rail side plate and the stiffener side plate in this way, the construction becomes easy and the vertical truss plate can be firmly attached.

According to a sixth invention, in the first to fifth inventions, the intersecting portion reinforced by the reinforcing member is an intersecting portion between a location where the hinge pin bracket is located in the cargo bed rail and a stiffener. This is a dump truck bed structure. As a result of detailed investigation and analysis of the load applied to each part of the loading platform of the conventional structure when loaded (full load) as described above, as well as the intersection of the stiffener and loading platform rail located in the front row of the loading section as described above In addition, it was found that a large load (stress) was concentrated due to the load of the load even at the intersection between the position where the hinge pin bracket is located and the stiffener. Therefore, by providing a reinforcing member at a portion where the load is concentrated, it is possible to reinforce more effectively while suppressing an increase in the weight of the loading platform.

In a sixth aspect based on the sixth aspect, the load carrier rail is composed of a pair of rail members extending in parallel to each other, and the reinforcing member is formed between the pair of rail members where the hinge pin bracket is located and the stiffener. A dump truck bed structure is provided at each intersection. According to such a structure, it is possible to reliably reinforce only the portion where the load is concentrated while suppressing an increase in the weight of the loading platform.

In an eighth aspect based on the seventh aspect, the carrier rail and the stiffener are formed in a substantially rectangular cross section, and the second reinforcing member is inclined between the side surface of the carrier rail and the side surface of the stiffener. A dump truck bed structure having a horizontal truss plate welded so as to be bridged.

In addition, as a result of analyzing the load applied to the intersection between the carrier rail and the stiffener where the hinge pin bracket is located, the inventor generates a force that twists in the width and the longitudinal direction of the bottom plate at the intersection with the hinge bracket as an axis. I understood that. Therefore, the crossing portion is effectively reinforced by attaching a reinforcing member composed of a lateral truss plate that is welded so as to cross between the side surface of the cargo bed rail and the side surface of the stiffener to the crossing portion, The stress in the torsional direction concentrated at the intersection can be dispersed and reinforced.

In a ninth aspect based on the eighth aspect, the reinforcing member further includes a rail side contact plate welded to a side surface of the load carrier rail, and a stiffener side contact plate welded to the side surface of the stiffener, The horizontal truss plate is welded between the rail side plate and the stiffener side plate. By thus welding the horizontal truss plate via the rail side plate and the stiffener side plate, the construction becomes easy and the vertical truss plate can be firmly attached.

According to the present invention, since the intersection between the stiffener and the loading platform rail where the load stress during loading is concentrated is reinforced by the reinforcing member, it is possible to exhibit excellent strength and rigidity while suppressing an increase in the weight of the loading platform.

1 is a side view showing an embodiment of a dump truck 100 according to the present invention. It is a side view of the loading platform 20 of the dump truck 100 according to the present invention. It is a perspective view which shows the state which turned over the loading platform 20 of the dump truck 100 which concerns on this invention, and was seen from diagonally. FIG. 3 is a perspective (perspective) view of the first reinforcing member 27 as seen from the rear of the vehicle. FIG. 3 is a perspective (perspective) view of the first reinforcing member 27 as viewed from the front of the vehicle. FIG. 3 is a perspective (perspective) view of the second reinforcing member 28 as viewed from the front of the vehicle. FIG. 6 is a perspective (perspective) view of the second reinforcing member 28 as viewed from the rear of the vehicle. FIG. 6 is a conceptual diagram for explaining the operation of the first reinforcing member 27. FIG. 6 is a conceptual diagram for explaining the operation of a second reinforcing member 28.

Next, embodiments of the present invention will be described with reference to the accompanying drawings. 1 and 2 are general views showing an embodiment of a dump truck 100 according to the present invention. As shown in the figure, the dump truck 100 is an ultra-large transport work machine having a vehicle weight exceeding several tens to several hundreds t and a height exceeding several m to 10 m. The dump truck 100 includes an engine compartment 12 and a cab 13 in front of a vehicle body frame 10 provided with front wheels 11a and rear wheels 11b, and a structure provided with a loading platform 20 on the vehicle body frame 10. It has become.

The engine room 12 includes a diesel engine and a generator (not shown). The engine is driven by the engine, the electricity is controlled by a control device such as an inverter, and then the rear wheel 11b is driven by an AC motor. It is supposed to run. In addition, a hydraulic pump is provided in the vehicle body frame 10, and pressure oil is sent to a hoist cylinder 30 for raising and lowering the loading platform 20 to expand and contract.

The hoist cylinder 30 is composed of a large hydraulic cylinder having a load resistance of several tens of tons or more consisting of a cylinder body and a cylinder rod, and the lower end side of the cylinder body is pivotally supported on the side surface of the body frame 10, The tip end side of the cylinder rod is pivotally supported on the lower surface of the loading platform 20. The hoist cylinder 30 is expanded and contracted by the hydraulic oil from the hydraulic pump described above, so that the entire loading platform 20 is vertically moved from the lying down state shown by the solid line in FIG. 1 to the standing state shown by the broken line with the hinge pin 21 as the axis. It swings.

FIG. 2 is a side view of the cargo bed 20 as seen from the side, and FIG. 3 is a perspective view of the cargo bed 20 as seen from the upper side. As shown in the figure, the loading platform 20 has a structure in which a loading platform rail 23 and a plurality of stiffeners 26a to 26i are provided outside a container-shaped loading section 22 for loading earth and sand.

The container-shaped stacking section 22 is formed of a rectangular steel plate bottom plate 22a, a steel plate front plate 22b welded so as to stand up from the bottom plate 22a, and both sides of the bottom plate 22a. The pair of side plates 22c (only one is shown in the figure) welded to both sides of the front plate 22b, and a bowl-shaped top plate 22d extending forward from the upper end of the front plate 22b.

And the loading platform rail 23 which consists of a pair of

rail members

23a and 23a is welded to the approximate center part of this bottom plate 22a. Each of the

rail members

23a and 23a is made of a box-shaped steel material having a rectangular cross section, and the container-like stacking portion 22 is mounted on the vehicle body frame 10 via a rubber pad p serving as a cushioning material. It has become. That is, the rubber pads p respectively provided on the lower surfaces (upper surface portions in FIG. 3) of the

rail members

23a and 23a are directly placed on the vehicle body frame 10 to load the loading platform 20 and the load loaded on the loading platform 20. All loads are transmitted to the body frame 10 side. As shown in the figure, the ends of the

rail members

23a and 23a protrude slightly forward from the front end of the bottom plate 22a.

In addition,

hinge pin brackets

24 and 24 are provided slightly rearward from the centers of the rail members 23a and 23b, respectively, so as to be coupled to the hinge pins 21 provided on the vehicle body frame 10 side. . Accordingly, the loading platform 20 can swing in the vertical direction as described above with the

hinge pin brackets

24 and 24 as axes. As shown in FIG. 3, hoist

pin brackets

25, 25 are provided on the bottom plate 22a in front of the

hinge pin brackets

24, 24, and the hoist cylinder 30 described above is provided on the hoist

pin brackets

25, 25. 30 cylinder rods are pin-coupled.

Also, a plurality (9 in this embodiment) of stiffeners 26a to 26i are provided on the bottom plate 22a so as to extend in the width direction orthogonal to the

rail members

23a and 23a. The stiffeners 26a to 26i are made of a steel plate having a channel (downward U shape) shape, and the bottom plate 22a is reinforced so as not to be deformed due to the weight of the load. In the present embodiment, as shown in FIG. 3, the first stiffener 26a is located at the edge of the bottom plate 22a on the front plate 22b side, and the ninth stiffener 24i is located at the rear edge of the bottom plate 22a. Welded.

The second stiffener 26b to the eighth stiffener 26h are welded on the bottom plate 22a between the first stiffener 26a and the ninth stiffener 26i so as to be positioned at substantially equal intervals. Of these, the hoist

pin brackets

25 and 25 are welded to the bottom plate 22a between the second stiffener 26b and the third stiffener 26c, respectively. Six stiffeners 26f are welded so as to be orthogonal to the rail members 23a and 23b.

Further, as shown in FIG. 3, the

rail members

23a and 23a are raised in the first half portion from the positions of the

hinge pin brackets

24 and 24, respectively, and are approximately twice the height of the first stiffener 26a to the fifth stiffener 26e. It is the height of. On the other hand, the rear half portions of the

rail members

23a and 23a are substantially the same height as the sixth stiffener 26f to the ninth stiffener 26i. Of the

rail members

23a, 23a, the entire rubber pad p provided on the entire lower surface (upper surface in the drawing) of the raised portions of the first half of the

hinge pin brackets

24, 24 is brought into contact with the body frame 10 as a cushioning material. It has become.

On the other hand, a stiffener including a plurality of lateral stiffeners 26j, 26k, 26m, and 26n extending in the vehicle width direction on the front plate 22b and top plate 22d sides and a plurality of

vertical stiffeners

26p, 26q, and 26r extending in the longitudinal direction of the vehicle, respectively. Are provided to reinforce each of them vertically and horizontally. Further, a pair of upper and lower vertical stiffeners 22s and 22t are also welded to the side plate 22c along its longitudinal direction.

In the present invention, each of the intersections of the

rail members

23a, 23a and the first stiffener 26a and each of the intersections of the

rail members

23a, 23a and the sixth stiffener 26f are respectively Reinforcing

members

27, 27, 27, 27 and second reinforcing

members

28, 28, 28, 28 are provided, and these reinforcing

members

27, 27, 27, 27, 28, 28, 28, 28 respectively The intersection is reinforced.

As shown in FIGS. 4 and 5, the first reinforcing member 27 includes a rail side contact plate 27 a welded to the side surface of the rail member 23 a and a stiffener welded from the upper surface to the side surface of the first stiffener 26 a. Side support plate 27b, vertical truss plate 27c that is welded so as to bridge the upper surface of stiffener side contact plate 27b from rail side contact plate 27a, and two support plates that support the side surfaces of this vertical truss plate 27c 27d and 27e.

That is, the first reinforcing member 27 is first welded to the side surface of the rail member 23a with a rail side abutting plate 27a made of steel plate, and the same stiffener side made of steel plate from the upper surface to the side surface of the first stiffener 26a. The contact plate 27b is welded. In the figure, the stiffener side abutting plate 27b is composed of two steel plates divided at the center of the upper surface of the first stiffener 26a. Further, since the corner portion of the first stiffener 26a is rounded, the corner portion of the stiffener side abutting plate 27b is rounded in advance so as to follow this.

Next, the vertical truss plate 27c made of a steel plate having a rectangular shape is welded so as to bridge the upper surface of the stiffener side abutting plate 27b from the surface of the rail side abutting plate 27a obliquely in the vertical direction. Thereafter, the steel

plate support plates

27d and 27e are welded to one side of the vertical truss plate 27c so as to reinforce the same so that the side surfaces of the stiffener side contact plate 27b are obliquely bridged from the surface of the rail side contact plate 27a. By doing so, the welded connection between the rail member 23a and the first stiffener 26a is reinforced. And since there are a total of four weld connection portions between the rail member 23a and the first stiffener 26a, the respective weld connection portions are reinforced by the first reinforcing member 27 having such a structure. The strength and rigidity of each intersection of the

rail members

23a, 23a and the first stiffener 26a are increased.

On the other hand, as shown in FIGS. 6 and 7, the second reinforcing member 28 is a rail side contact plate that is welded to the side surface of the rail member 23a so as to straddle the sixth stiffener 26f immediately below the hinge pin bracket 24. 28a, a stiffener side abutting plate 28b welded from the upper surface to the side surface of the sixth stiffener 26f, and a pair welded so as to bridge between the side surfaces of the stiffener side abutting plate 28b from the rail side abutting plate 28a.

Horizontal truss plates

28c, 28c.

That is, the second reinforcing member 28 is first welded to the side surface of the rail member 23a with a steel plate rail side abutting plate 28a, and also from the upper surface to the side surface of the sixth stiffener 26f. The contact plate 28b is welded. The stiffener side abutting plate 28b is also composed of two steel plates divided at the center of the upper surface of the sixth stiffener 26f. Further, since the corner portion of the sixth stiffener 26f is rounded, the corner portion of the stiffener side abutting plate 28b is also rounded in advance so as to follow the corner portion.

Next, the steel-made

horizontal truss plates

28c and 28c are welded so as to be obliquely bridged between the side surface of the stiffener side contact plate 28b from the surface of the rail side contact plate 27a. The

lateral truss plates

28c and 28c have a curved shape that covers the connection portion between the rail member 23a and the sixth stiffener 26f in a triangular shape (truss shape) as shown in the figure, and the stiffener side abutting plate 28b. It is welded continuously from the side surface to the corner. Similarly, since there are a total of four welded connection portions between the rail member 23a and the sixth stiffener 26f, the respective welded connection portions are reinforced by the second reinforcing member 28 having such a structure. Thus, the strength of each intersection of the

rail members

23a, 23a and the sixth stiffener 26f is increased.

Thus, the first reinforcing

members

27 and 27 are provided at the intersections between the

rail members

23a and 23a and the first stiffener 26a and at the intersections between the

rail members

23a and 23a and the sixth stiffener 26f, respectively. 27, 27 and the second reinforcing

members

28, 28, 28, 28 can effectively reinforce the stacking portion 22 while suppressing an increase in weight. *

FIG. 8 is a conceptual diagram for explaining the action of the first reinforcing member 27, and FIG. 9 is a conceptual diagram for explaining the action of the second reinforcing member 28. First, as shown in FIG. 8, when the loading portion 22 is fully loaded with loads such as crushed stones and earth and sand, the load is applied to the loading frame 10 via the

rail members

23a and 23a as shown in FIG. In addition, a load is generated such that both sides of the bottom plate 22a bend downward due to its weight. In order to support such a load, as described above, a plurality of stiffeners 26a to 26i are provided on the bottom plate 22a side so as to extend in the width direction. As shown in Fig. 2, the vehicle is inclined forward.

For this reason, the load applied to the plurality of stiffeners 26a to 26i is not uniform and increases as the vehicle moves forward, and the largest load is applied to the first stiffener 26a at the tip. That is, in the first stiffener 26a located at the tip, a large bending moment is generated downward with the intersection (welded portion) with the

rail members

23a and 23a as a fulcrum.

Since the present invention includes the first reinforcing member 27 as described above at the intersection between the rail member 23a to which the greatest bending moment (load) is applied and the first stiffener 26a, FIG. As shown, the strength and rigidity of the part are greatly improved. As a result, it is possible to reduce (stress distribution) the load caused by the bending moment concentrated at the intersection. Moreover, since the first reinforcing member 27 is composed of several steel plates as described above, the loading platform 20 as a whole is only slightly increased in weight and does not cause a significant increase in weight.

On the other hand, the loading platform 20 is pin-coupled to the vehicle body frame 10 side via

hinge pin brackets

24 and 24. As shown in FIG. 9, the position where the

hinge pin brackets

24, 24 are provided is located on the rear side of the center of the loading platform 20, so that the loading platform 20 has its width around the

hinge pin brackets

24, 24. When a force that swings in the direction is generated, the force is concentrated at the intersection (welded portion) between the

rail members

23a, 23a and the sixth stiffener 26f via the

hinge pin brackets

24, 24. A stress that twists in the longitudinal and width directions of the bottom plate 22a is generated in the portion.

The present invention further includes the second reinforcing member 28 as described above at the intersection (welded portion) between the rail member 23a and the sixth stiffener 26f, which is loaded by the stress in the large torsional direction. Therefore, the strength and rigidity of the portion can be significantly improved, and thereby the force in the torsional direction generated at the intersecting portion can be reduced (stress distribution). In addition, like the first reinforcing member 27, the second reinforcing member 28 is also composed of several steel plates, so that the loading platform 20 as a whole is only slightly increased in weight, resulting in a significant increase in weight. Nor.

As described above, the present invention selects two regions in the loading portion 22 where stress is particularly concentrated during loading, and reinforces these regions with the first reinforcing member 27 and the second reinforcing member 28, respectively. It is possible to exhibit excellent strength and rigidity while suppressing an increase in the weight of the whole 20. In the present embodiment, an example has been described in which a total of four first reinforcing members 27 are provided on both sides of each intersection of the two

rail members

23a, 23a and the first stiffener 26a, but as described above. Of the first stiffener 26a, a larger load is applied to the outer portion than the inner side of the rail member 23a. Therefore, the first reinforcing member 27 is provided only on the outer side of the rail member 23a, and the first reinforcing member on the inner side of the rail member 23a is provided. The member 27 may be omitted. Similarly, any one of the second reinforcing members 28 may be omitted.

DESCRIPTION OF SYMBOLS 100 ... Dump truck 10 ... Body frame 20 ... Loading platform 22 ... Loading part 22a ... Bottom plate 22b ... Front plate 22c ... Side plate 22d ... Top plate 23 ... Loading platform rail 23a ... Rail member 24 ... Hinge pin brackets 26a-26i ... First stiffener- 9th stiffener 27 ... 1st reinforcement member 27a ... Rail side contact plate 27b ... Stiffener side contact plate 27c ... Vertical truss plate 28 ... 2nd reinforcement member 28a ... Rail side contact plate 28b ... Stiffener side contact plate 28c ... Horizontal Truss board

Claims

A container-shaped loading section located on the body frame of the dump truck;
A cargo bed rail provided on the bottom plate side of the loading portion so as to extend in the front-rear direction of the vehicle body;
A plurality of stiffeners provided on the bottom plate side of the stacking unit so as to intersect the cargo bed rail;
A dump truck bed structure characterized by reinforcing a crossing portion of the stiffener and the bed rail with a reinforcing member.
2. The dump truck bed structure according to claim 1, wherein the intersection reinforced by the reinforcing member is an intersection of the carriage rail and a stiffener positioned on the vehicle body front side of the bottom plate.
The carrier rail is composed of a pair of rail members extending in parallel to each other,
The dump truck bed structure according to claim 2, wherein the reinforcing member is provided at each intersection of the pair of rail members and the stiffener.
The cargo bed rail and the stiffener are formed in a substantially rectangular cross section, and the crossing portion reinforced by the reinforcing member is higher on the cargo bed rail side than the stiffener,
The dump truck loading platform structure according to claim 2, wherein the reinforcing member has a vertical truss plate that is welded so as to be bridged obliquely between the loading rail rail side surface and the upper surface of the stiffener.
The reinforcing member further includes a rail side contact plate welded to a side surface of the cargo bed rail, and a stiffener side contact plate welded to the upper surface of the stiffener, and the vertical truss plate includes the rail side contact plate and the stiffener. 5. The dump truck bed structure according to claim 4, wherein the structure is welded between the side contact plates.
2. The dump truck bed structure according to claim 1, wherein the intersection portion reinforced by the reinforcing member is an intersection portion of the carriage rail where a hinge pin bracket is located and a stiffener.
The carrier rail is composed of a pair of rail members extending in parallel to each other,
The dump truck loading platform structure according to claim 6, wherein the reinforcing member is provided at each intersection of the pair of rail members where the hinge pin bracket is located and the stiffener.
The cargo bed rail and the stiffener are formed to have a substantially rectangular cross section, and the second reinforcing member has a lateral truss plate that is welded so as to be bridged obliquely between the side surface of the cargo bed rail and the side surface of the stiffener. The dump truck bed structure according to claim 6.
The reinforcing member further includes a rail side contact plate welded to the side surface of the load carrier rail, and a stiffener side contact plate welded to the side surface of the stiffener, and the lateral truss plate includes the rail side contact plate and the stiffener. The dump truck bed structure according to claim 8, wherein the dump truck bed is welded between the side contact plates.