KR200325423Y1 - Temporary bridge composed of selectively prestressed bridge girder, apparatus for preventing falling off bridge and supporting apparatus having multiple supporting points - Google Patents

Abstract

The present invention is designed to increase the load capacity, prevent falling-off, and maintain and maintain the long span between the beams and reduce the beam size. The bridge girders composed of the prestressed multi-layer composite double beams, the multi-point support device and the fall prevention device are connected to the upper part of the temporary vent, and the tension device for maintenance is installed on the lower part of the bridge girder. Multi-layered double beams welded up and down with different upper and middle H beams, Multi-layered double-layer beams welded up and down with different top and bottom H beams with different stiffness By welding or bolting the beam, the intermediate H beam and the lower H beam up and down, and then introducing prestress and welding or bolting the welding or bolting completely. Prestressed multi-layer composite double beams are fabricated, and the anti-falling device is installed on both sides of the temporary vent, and the multi-point supporting device is installed on the temporary vent in the longitudinal direction of the temporary bridge. The prestressed multi-layer composite double beam is mounted on the center apparatus of the temporary bridge on the bridge device, and the multi-layer composite double beam is installed on both points of the temporary bridge of the temporary bridge, and at the center of both temporary vents of the temporary bridge By installing a multi-layered double beam and connecting the connection between the multi-layered composite double beam and prestressed multi-layer composite double beams installed adjacent to each other, or bolted or welded, and installing the tensioning device under the multi-layered double beam, A. The tension device is connected to each other at the bottom of the rest multi-layer composite double beam To the bridge.

Description

Temporary bridge composed of selectively prestressed bridge girder, apparatus for preventing falling off bridge and supporting apparatus having multiple supporting points}

The present invention is designed to increase the load capacity and to prevent fallout while reducing the length of the span and reducing the beam height, and to pre-stress the multi-layer double beam, multi-layer composite double beam, and prestress with multiple H beams of different rigidity. A bridge girder consisting of a multi-layer composite double beam, a multi-point support device, and a fall prevention device are connected to an upper part of a temporary vent, and a tension device for maintenance is installed below the bridge girder.

Multi-layered double beam with welded top and bottom H beams with different stiffness up and down, Multi-layered double-layer beam with welded top and bottom H beams with different stiffness up and down, different rigidity We fabricate bridge girders consisting of prestressed multi-layer composite double beams in which the upper H beam, the intermediate H beam and the lower H beam are welded up or down, and then prestressed and completely welded or bolted. ,

In order to install the prestressed composite double beams on the temporary vents installed in the center of the temporary bridges, the multi-stage composite devices for the prestressed multi-ply composite beams are installed after installing multiple points of support on both sides of the temporary vents in the longitudinal direction of the temporary bridges. It is installed on the bridge device, while installing the multi-point support device in the inner length direction of the bridge bridge on one side of the tent of the temporary bridge, while installing the bridge device on it and the multi-layer composite double beam on the After installing the multi-layered double beams between the multi-layered composite beams and the prestressed composite beams, bolted joints are formed on the abdomen of the H-beam to install temporary bridges.

At this time, in order to prevent the bridge girders from falling on the temporary vents on both sides in the width direction of the temporary vents, a fall prevention device is installed, and the load bearing capacity of the bridge is reduced by using the temporary bridges for a long time, thereby maintaining the load capacity. For the repair, the tensioner is installed at both sides of the lower part of the multilayer plywood at a certain distance, and the tension device is installed with the strands connecting them, and the multilayer composite plywood and the prestressed multilayer composite plywood are installed with the multilayer plywood interposed therebetween. It is a temporary bridge with a fixing device installed at each lower part and connected with a stranded wire.

The bridge device is developed to be applied to the temporary bridge of the present invention as a bridge device to improve the existing bridge device.

The purpose of installation of temporary bridges in the above method is to temporarily install bridges for vehicles and people to install permanent bridges. H-beams can be connected vertically in multiple layers, and prestressed to increase rigidity. If the prestressed multi-layer composite double beams with prestress are applied to the bridge according to the moment action stress, the effect of offsetting the stress caused by the load acting on the bridge and the stress that cancels in the future will be obtained. In the present design, a large number of stabilizing devices are installed on both sides of the temporary vent, and the fixed length must be increased without critical length of the bending moment stress acting on the girder. By installing a multi-point support device Since the bending moment acting on the bridge girders extends a certain length on the temporary girder as the government part is placed on the multi-point supporting device, the multi-point supporting device installed by the bridge girders supports the bridge girder so that the gentle bending moment is acted on. The bridge girder can be installed and the beam height can be reduced.

In addition, a fall prevention device for preventing the bridge girder from falling off due to an earthquake or the like is installed on both sides of the width direction of the temporary vent, and when the load capacity of the bridge needs to be increased, additional stress is introduced into the bridge girder. In order to provide a method of installing a temporary bridge to prepare for the maintenance of the bridge by installing a double tension device in the lower part of the bridge girder.

Currently, the installation method of bridge construction is to connect the beams to each other to establish a temporary vent, and to weld the temporary vent integrally thereon to install a temporary bridge, and then install a double-plate or steel plate on it to temporarily allow the vehicle or person to pass. There are existing conventional methods to install, a method of introducing prestress using a high strength steel bar, and a method of constructing a continuous assembly of trusses. The conventional method has a problem that temporary bridges are reduced to 5.0 ~ 8.0m because of the shortage of temporary bridges, and the temporary bridges are lost during flooding.The method using high strength steel rods has a ramen type negative effect and prestress. It is hypothesized by the long span, but this method is able to cancel the stress, but the rigidity of the upper beam cannot be increased due to the introduction of prestress by non-attached steel rods, so it cannot effectively cope with the deflection and vibration of the temporary bridge. In other words, long periods are possible in terms of stress, but because the upper beam is less rigid, a lot of deflection occurs, so that the actual use is restricted. In addition, the method of constructing the truss as a continuous assembly can be long and long, but since the material must be imported and installed from abroad, there is a problem in smooth supply and demand of the material. The problem has been raised due to poor use.

The present invention proposed to improve the above problems is to install a temporary bridge by installing a multi-layered double beam, multi-layer composite double beams and prestressed multi-layer composite double beams on a temporary vent, the bridge girder by welding the H-beams in multiple layers To install and install a temporary bridge using multi-layered composite double beams with prestress to cope with bending stress, develop a practical bridge installation method that can effectively cope with stiffness, deflection and vibration of bridge girders. At the same time, by developing and using a supporting device that can reduce the lower stress and side reaction of the temporary vent by enabling temperature contraction and expansion in the longitudinal direction of the temporary bridge, it can be easily manufactured and used in the field at a lower cost than the current products. Of economical and practical temporary bridges Provide the installation method, install the fall prevention device to prevent the bridge girder from falling off, and install the tensioning device in the lower part of the bridge girder so that the load capacity of the temporary bridge can be increased in the future. To provide a construction method for the construction of temporary bridges.

1 is a view showing the installation of a temporary bridge of the present invention as a whole.

2 is a view showing a multi-point support device and a fall prevention device installed on a temporary vent of a temporary bridge of the present invention.

3 is a view showing a multi-point support device of the present invention.

4 shows another embodiment of the multi-point support of FIG. 3.

5 is a view showing an A-A cross section of a multi-layered double beam that is the central portion of the temporary bridge of FIG.

6 is a cross-sectional view illustrating a B-B cross section of a prestressed multi-layer composite double beam installed at a central point of the temporary bridge of FIG.

Figure 7 is a view showing the C-C cross-section of the multi-layer composite double beam installed in the temporary vents on both sides of the temporary bridge of Figure 1;

<Description of the symbols for the main parts of the drawings>

A ... bridge girder

1 ... Chair 2 ... Double vent

3 ... handrail 4 ... hypothesis

5 ... Steel 6 ... Foundation

7 ... Foundation Support

10 ... Temporary bridge

20 ... multilayered beam 21 ... top H beam

22 ... intermediate H beam 23 ... lower H beam

30 ... Multipoint Support 31 ... Stool Supports

32 ... Support 33 ... Spacing Support

40 ... Antifalling device 41 ... Vertical stand

42 ... crossbar

50 ... tensioner 51 ... anchorage

52 ... the strand

60 ... Prestressed Multilayer Composite Double Beam

70 ... Multilayer Composite Double Beam

The present invention is a multi-layered double beam (20) made by welding the upper and lower H beams 21 and the intermediate H beams 22 having different rigidity up and down, and the upper H beams 21 and the intermediate H beams 22 having different rigidities. And a multi-layer composite double beam 70 in which the lower H beams 23 are welded up and down, and the upper H beams 21 and the intermediate H beams 22 and the lower H beams 23 having different rigidities are vertically welded or The bridge girders (A) made of prestressed multi-layer composite double beam (60), which is pre-bolted and then prestressed and fully welded or bolted to weld or bolting, are manufactured.

The multi-point supporting device 30 is installed on both sides of the temporary vent 4 in the longitudinal direction of the temporary bridge 10 in the temporary vent 4 installed at the center of the temporary bridge 10, and a plurality of the teaching device 1 is installed. Later, the prestressed multi-layer composite double beam 60 is installed on the bridge device 1, and the multiple lengths of the prestressed multilayer beam 60 are installed in one side of the temporary bridge 4 at both sides of the temporary bridge 10 in the longitudinal direction of the temporary bridge 10. The multi-layer composite double beam 70 and the prestressed multi-layer composite double beam 60 while installing the point supporting device 30 while installing a plurality of stagger devices 1 thereon and the multi-layer composite double beam 70 installed thereon. A multi-layered double beam 20 is installed therebetween, and a temporary bridge 10 is installed by forming a connection part 6 which is bolted to the abdomen of the H beam.

At this time, in order to prevent the bridge girders (A) from falling on the temporary vent (4) on both sides of the width direction of the temporary vent (4), the fall prevention device (40) is installed, the temporary bridge 10 Long-term use, the load-bearing capacity of the bridge is lowered, the anchorage 51 is installed on both sides at a constant distance to the lower portion of the multi-layered double beam 20 for maintenance for increasing the load capacity, the tension wire 52 is connected to them While the device 50 is installed, the fixing unit 51 is installed at the lower portion of the multi-layer composite double beam 70 and the prestressed multi-layer composite double beam 60 provided with the multi-layer double beam 20 interposed therebetween, and the strand wire 52. It is characterized in that the temporary bridge 10 is provided with a double tension device 50 is connected to each other.

The bridge device (1) is developed to apply to the temporary bridge 10 of the present invention as an improvement of the existing bridge device.

Method for installing a temporary bridge using the bridge girder is as follows.

a) Assemble the hypothesis vent (4) thereon while installing the foundation (6) to install the temporary vent (4) of the temporary bridge (10) and the foundation support (7) for installing the temporary vent (4). Making;

b) a multi-layered beam 20 interconnecting the upper H beam 21 and the intermediate H beam 22 at the ground surface, the upper H beam 21 and the intermediate H beam 22 and the lower H beam 23. ) Is welded or bolted completely while pre-stressing is introduced after the multi-layer composite double beam 70 and the upper H beam 21 and the intermediate H beam 22 and the lower H beam 23 are interconnected or welded. Manufacturing a bridge girder (A) made of one prestressed multilayer composite double beam (60);

c) installing a multi-point support device (30) provided with a plurality of stave devices (1) on the temporary vent (4) to extend a predetermined length from the temporary vent (4) in the longitudinal direction of the temporary bridge (10);

d) the prestressed multilayer composite double beam 60 at the intermediate point portion on the temporary vent 4, the multilayered composite double beam 70 at both side portions, and the prestressed multilayer composite double beam 60 and the multilayered composite double beam 70. Between the multiple beams (A) of the plurality of bridge girders (A) installed adjacently in the width direction while being installed in the longitudinal direction using a connecting portion 6 by bolts or welding to the abdomen of the H-beams between the steel (5) Assembling and mounting on the multi-point support device 30 while fixing using;

e) installing the fall prevention device 40 on both sides of the bridge girders (A) installed in the temporary vent (4);

f) Prists installed on both sides with the tension device 50 connected by the strands 52 and the multi-layered plywood 20 interposed therebetween with a predetermined interval on the lower part of the multi-layered plywood 20 and installing the anchors 51 on both sides. Installing the tension device 50 connected by the strand 52 while installing the anchor 51 in the multi-layer composite double beam 60 and the multi-layer composite double beam 70, respectively; And

g) installing the perforated plate (2) in the upper portion of the hypothesized bridge girder (A) and install the railings (3) on both sides to clean up the surroundings and install to allow passage to the temporary bridge (10) There is this.

Hereinafter, described in detail by the accompanying drawings the configuration and operation of the present invention as follows.

1 is a view showing the installation of the temporary bridge of the present invention as a whole, a multi-layered double beam 20 produced by welding the upper and lower H beams 21 and intermediate H beams 22 having different stiffness up and down, stiffness each other Multi-layered composite double beam 70 in which other upper H beams 21, intermediate H beams 22, and lower H beams 23 are welded up and down, upper H beams 21 and intermediate H beams 22 having different rigidities. Bridge girder (A) consisting of a prestressed multilayer composite double beam 60 in which the pre-stress is introduced and the pre-stress is introduced and the weld or bolting is completely welded or bolted. To create the

The multi-point support device 30 is installed on both sides of the temporary vent 4 in the longitudinal direction of the temporary bridge 10 in the temporary vent 4 installed at the center of the temporary bridge 10. Afterwards, the prestressed multi-layer composite double beam 60 is installed on the bridge device 1, and in the longitudinal direction of the temporary bridge 10 on one side of the temporary bridge 4 at both sides of the temporary bridge 10. While installing the multi-point support device 30 while installing a plurality of stagger devices 1 thereon and the multi-layer composite double beam 70 is installed thereon, the multi-layer composite double beam 70 and the prestressed multi-layer composite double beam 60 After installing the multi-layered double beams (20) between the (6) to form a connecting portion (6) connected by bolts to the abdomen of the H beam to install the temporary bridge (10).

At this time, in order to prevent the bridge girder A from falling on the temporary vent 4, a fall prevention device 40 is installed at both sides in the width direction of the temporary vent 4, and the temporary bridge 10 is installed. After long periods of use, the load-bearing capacity of the bridge is lowered, so that the anchorage 51 is installed at both sides at a lower distance from the bottom of the multi-layered double beam 20 for maintenance to increase the load-bearing force, and the strand wire 52 connecting them is installed. While the tensioning device 50 is installed, the fixing unit 51 is installed at the lower portion of the multi-layer composite double beam 70 and the prestressed multi-layer composite double beam 60 provided with the multi-layer double beam 20 interposed therebetween, and the strand wire 52 It is characterized in that the temporary bridge 10 is provided with a double installed tensioning device 50 is connected to each other.

The bridge device (1) is developed to apply to the temporary bridge 10 of the present invention as an improvement of the existing bridge device.

Installing the prestressed multi-layer composite double beam 60 on the center temporary vent 4 is the bridge in which the pre-stress is additionally connected while connecting three H beams since the largest parent moment acts in the center in the case of a continuous bridge. It is to install the girder A, and to install the multi-layer composite double beam 70 at both points, the parent moments generated at both points are relatively small compared to the amount of parent moments generated at the center. Instead of using a bridge girder (A) connecting the three H-beams up and down, the multi-layered double beam (20) installed in the center of the point, that is, the center of the point is connected to the two H-beams up and down each other point The moment acting on the center part is the static moment, which is connected to the bridge girder (A) installed in the center. Used.

Using three or two H beams in the manufacturing of the bridge girder (A) above is to select a bridge girder (A) according to the present invention, by using the above-mentioned number of H beams to produce a bridge girder (A) It can be hypothesized that the bridge can be hypothesized, and the selection of these conditions can be selectively used according to the site opinion at that time, and the number of the H beams is variable.

2 is a plan view showing a multi-point support device and a fall prevention device installed on the temporary vent of the temporary bridge of the present invention, the multiple installed inside the temporary bridge 10 so that a predetermined length is extended to both sides of the temporary vent (4) A plurality of bridge devices 1 are installed on the point support device 30, and a portion of the bridge girder A is mounted on the multi point support device 30. Since a certain portion of the multi-point support device 30 installed in this way is installed over a certain portion of the bridge girders (A), when the load acts on the temporary bridge (10), the bending moment of the portion to be applied smoothly acts as a bridge By improving the load capacity of the girder (A) it is possible to reduce the long span and sentence height. The number of the teaching device 1 installed on the multi-point support device 30 is three to five, preferably three, the installation position of the teaching device 1 is a multi-installation on the temporary vent (4) Not only the point support device 30, but also is installed in the multi-point support device 30 of a portion extending out of a predetermined length and the installation position of the chair device 1 is installed according to the site conditions, such as working load. The detailed structure of the multi-point support device 30 will be described in detail in FIGS. 3 and 4.

The fall prevention device 40 is installed on both sides in the width direction of the temporary vent (4) as shown in Figures 3, 4 and 7 steel on both sides of the bridge girders (A) installed in the temporary vent (4) Install using (5) but form a trapezoidal shape using the steel (5) in the side of the temporary vent (4) as shown in Figure 2 and then the temporary steel material (5) extending from the vertex of the trapezoidal shape 7 and a plurality of vertical stands 41 on the side of the bridge girder A on the steel 5 connected to the temporary vent 4 at the vertex of the trapezoidal shape as shown in FIG. The crossbar 42 is installed diagonally on the upper surface of the vertical stand 41 and the lower end of the trapezoidal shape so as to support the stand 41 by welding or bolting.

3 is a view showing a multi-point support device of the present invention, to be installed to extend a predetermined length in the longitudinal direction of the temporary bridge 10 on the temporary vent (4), on the multi-point support device 30 Install a plurality of chair devices (1).

As shown in FIG. 2, the multi-point support device 30 is provided with a predetermined number of horizontally on the pedestal device pedestal 31 on the temporary vent 4 while extending a predetermined length to the outside of the temporary vent 4. After installation using the cross-section after the installation on the bridge girders (A) so as to be perpendicular to the bridge device bracket 31 installed horizontally and the end portion and the temporary vent (4) A support 32 is installed diagonally at a lower side of a predetermined position so as to support the pedestal pedestal 31.

FIG. 4 is a view showing another embodiment of the multi-point support device of FIG. 3, in which the multi-point support device 30 is installed on the temporary vent 4 in FIG. 3, but the pedestal support unit ( 31, the support 32 is installed to extend to the base support portion 7 where the temporary construction of the temporary vent 4 begins to prevent the bending of when the length of the support 32 is long to support the load In order to install the interval support 33 installed diagonally on a certain portion of the support 32 in a place where the pedestal unit 31 and the temporary vent (4) meet at a right angle.

The bridge girder (A) by the plurality of bridge device (1) installed on the multi-point support device 30 of Figures 3 and 4 to freely behave by the temperature, impact, etc. on the temporary vent (4) The multi-point support device 30 is installed to extend a predetermined length to the outside of the temporary vent (4) to widen the distribution and reduction of the load acting on the bridge girder (A).

FIG. 5 is a cross-sectional view illustrating a cross section AA of a multi-layered double beam, which is a central portion of the temporary bridge of FIG. 1, wherein the multi-layered composite double beam 70 is formed as a multi-layered double beam 20 connecting the upper portion 21 and the intermediate H beam 22 up and down. And a prestressed multi-layer composite double beam (60) to form a connection girder (6) connected to the abdomen of the H beam by bolts to form a bridge girder (A), and to install a double hole plate (2) thereon The temporary bridge (10) is installed by installing handrails (3) on both sides of the upper part.

FIG. 6 is a cross-sectional view of the BB section of the prestressed multi-layer composite double beam installed at the central point of the temporary bridge of FIG. 1, wherein the upper H beam 21, the middle H beam 22, and the lower H beam 23 are vertically disposed. Prestressed multi-layer composite double beam 60, which is pre-stressed or temporarily bolted and then pre-stressed and welded or bolted fully welded or bolted, installed on a central temporary vent 4, which is the central part of the temporary bridge 10. To form a bridge girder (A) and to install a double hole plate (2) thereon and to install the handrails (3) on both sides of the upper portion of the temporary bridge (10) to install the temporary bridge (10). In the middle of the temporary vent (4), when the load is applied to the temporary bridge (10) is the place where the parent moment acts the steepest, so to use a multi-layered composite beam with a prestress is introduced to resist such stress.

FIG. 7 is a cross-sectional view showing a CC cross-section of a multi-layer composite double beam installed in a temporary vent, which is a point on both sides of the temporary bridge of FIG. 1, and the upper H beam 21, the middle H beam 22, and the lower H beam 23 are vertically up and down. The welded multilayer composite double beam 70 is installed on one side of the temporary vent 4 at both sides of the temporary bridge 10 to form a bridge girder A, on which a perforated plate 2 is installed, and the temporary bridge 10 Install the handrails (3) on both sides of the upper part of the temporary bridge (10).

By installing a temporary bridge using a bridge girder made by connecting a plurality of H beams up and down, the load capacity of the cross section can be increased to lengthen the space, and the lower space of the bridge can be expanded to reduce the height of the bridge, Multi-point supporting device is installed at the bridge, and a plurality of bridge devices are installed, and prestress is installed at the bridge girders installed at the intermediate temporary vents, thereby reducing the magnitude of the applied stress acting on the temporary bridge while providing a relatively gentle stress range. In addition, the stability of the bridge is improved, and the fall arrest device is installed to prevent the girder girder from escaping from the temporary vent due to an earthquake or an impact from the outside. The tension device is used to introduce additional tension to the bridge girder when it affects the safety of the bridge. It is very useful to have multiple installation and maintenance and management functions at the same time, and it has the merit to construct a temporary bridge considering the safety of the bridge.

Claims (8)

Bridge girder consisting of multi-layered double beams, multi-layered composite double beams and prestressed multi-layered composite double beams, which are connected to each other up and down by means of vertical flanges, is installed on the temporary construction according to the distribution of stress acting on the temporary bridge. Install a multi-point support device provided with a plurality of bridge devices between the temporary vent and the bridge girder, and installs a fall prevention device on both sides in the width direction of the bridge girder installed on the temporary vent, the lower portion of the bridge girder The bridge is a temporary bridge consisting of a bridge girder, an anti-falling device and a multi-point support device, which is connected to a multi-layered H-beam, characterized in that the tension device is installed, and optionally introduced prestress. The method of claim 1 The multi-layered double beam is manufactured by welding or bolting the upper and lower flanges up and down to the upper and lower H beams. The H beam is characterized in that the moment load is relatively small and the center beam is installed at the center between the positive moments. Temporary bridge consisting of bridge girder, multi-point supporting device, bridge girder with multi-layer connection and optional prestress The method of claim 1, The multi-layer composite double beam is manufactured by welding or bolting the upper and lower flanges to the upper and lower H beams, the upper and lower H beams, and installed at a point where a relatively small amount of parent moments act. A bridge girder consisting of bridge girders with multiple layers of H beams and optionally pre-stressed, anti-falling devices and multi-point support. The method of claim 1, The prestressed multi-layer composite double beam is manufactured by welding or bolting the upper H beam, the intermediate H beam, and the lower H beam by welding or bolting the upper and lower flanges up and down with each other while introducing prestress. A temporary bridge consisting of a bridge girder, a fall prevention device, and a multi-point support device that connects H-beams in multiple layers and selectively introduces prestresses. The method of claim 1, The multi-point support device is installed between the temporary vent and the bridge girder, the installation of three to five bridges, connecting the H-beams in multiple layers, characterized in that the predetermined length is extended to the outside of the temporary vent, optionally Prestressed bridge girders, temporary bridges consisting of fall prevention devices and multi-point support devices. The method of claim 5, The multi-point support device is installed on the bridge girders to be orthogonal to the bridge pedestal and then to install a certain number of bridge pedestals in the bridge length direction on the construction vents using steel to extend a certain length to the outside of the construction vents And a pedestal device at an orthogonal part, and the supporter is diagonally installed at the end of the pedestal device stand extending outwardly, and at a predetermined position on the lower side of the temporary vent, or the support for supporting the pedestal device pedestal is provided. H-beams, characterized in that the installation is extended to the base support to start the construction of the temporary vent, the interval support is installed diagonally installed in a certain portion of the support at the intersection of the pedestal unit and the construction vent at a right angle. Bridge girder with optional prestress Hypothesis bridge consisting of bridge protection device and a multi-point support structure. The method of claim 1, The fall prevention device is installed by using steel materials on both sides of the width direction of the bridge girders installed on the temporary vents, but forms a trapezoidal shape by using steel materials on the side of the temporary vents, and then installs the steel extending from the vertex of the trapezoidal type. Each of which is connected to the steel beams extending from the temporary vent while installing a plurality of vertical bars on the side of the bridge girder, and the horizontal bars are diagonally connected to the upper surface of the vertical bar and the lower end of the trapezoidal shape so as to support the vertical bars. A temporary bridge consisting of a bridge girder, an anti-falling device and a multi-point support device that connects H-beams, which are characterized by being welded or bolted, in a multi-layered manner, and optionally introduces prestress. The method of claim 1, The tensioning device is provided with a fixing device in the lower portion of the multi-layer composite double beam and the prestressed multi-layer composite double beam, which is provided with a tension device connected to the strands and the multi-layer double beams installed at both sides at a constant distance from the bottom of the multi-layer double beam. H-beams characterized by the double installation of tensioning devices connected to each other by strands, and the bridge girders, pre-stressed bridge girders and pre-stressed bridges, and temporary bridges consisting of multi-point support devices.