JP5934080B2 - Rapid construction bridge and its construction method - Google Patents

Description

  The present invention relates to a rapid construction bridge capable of increasing the scale of a bridge that can be constructed by a crane having a limited capacity, mainly for the purpose of early recovery from a disaster, and the construction method thereof.

  Due to tsunami and earth and sand disasters, bridges crossing rivers, coastal areas, and mountainous bridges are washed away, and roads are divided. In that case, it is necessary to restore the bridge in some way.

  Normally, when the scale of the bridge is small, a girder bridge composed of an I-girder as a main girder, a horizontal girder (floor receiving girder), a floor slab, etc. is installed. Girder bridges generally employ a construction method such as collective construction using a crane or delivery construction.

  There are also alternative emergency assembly bridges that can be erected in the event of a disaster such as an earthquake.

  For example, Patent Documents 1 and 2 are prior art documents related to an emergency assembly bridge.

  In addition, Non-Patent Document 1 introduces various emergency assembly bridges entitled “Disaster Dispatching Activities and Bridge Equipment of the Ground Self-Defense Force Facility Department” and “Current Status of Emergency Bridges and Disaster Preparation”.

JP 2009-007752 A Japanese Patent No. 3028909

Bridge and Foundation August 2012 Issue, Construction Books, Inc., pages 64-104

  At the time of disaster recovery, lifesaving is the top priority. In this case, it is necessary to install it in a short time (within a few days) under the restrictions.

  Doing it manually requires dozens of workers, but it is difficult to secure personnel in an emergency.

  Moreover, it takes time to set a delivery device for constructing a bridge by delivery construction.

  Furthermore, in an emergency, it is extremely difficult to procure a large crane that can be used to build an emergency bridge. When the scale of the bridge increases, the weight of the main girder increases. However, if the arm length of the crane is increased, heavy objects cannot be hung.

  In the conventional bridge structure, when it is erected from one side, a crane capable of hanging at least one main girder is required. Therefore, the lack of a large crane at the time of a disaster meant that there was a limit to the span length that could be installed.

  The present invention is intended to solve such a problem, and in cases such as when rapid construction is required for early restoration mainly in the event of a disaster, the same crane is used to increase the scale of a bridge that can be constructed. The purpose is to provide a construction bridge and its construction method.

  The rapid construction bridge according to the present invention is constructed with a plurality of parallel main girders installed between opposing main girder receiving portions that give the span length, and a gap in the bridge axis direction between the plurality of main girders. In a bridge consisting of multiple floor slab support girder and floor slab installed on the floor slab support girder, the main girder is a plurality of main girder units that can be individually installed between the main girder receiving parts by cranes. The main girder unit is configured to connect the main girder units in a direction perpendicular to the bridge axis so as to ensure rigidity as a single main girder.

  The function of the main girder needs to resist bending and shear caused by vehicle traffic so that the vehicle can pass. In the case of general I-girder, the main girder flange resists bending and the web resists shearing. However, bending is critical in design.

  The weight that can be installed by a crane and the span length that can be installed are limited for each crane. On the other hand, not only in terms of economic efficiency, but also available cranes are limited in emergency situations where rapid construction is required.

  Therefore, in the present invention, one main girder is divided into two or more main girder units to reduce the weight of a single member, while ensuring the rigidity and bending load resistance of the main girder as an assembly of main girder units. I was able to do it. As a result, if the crane has the same capacity, it can be constructed with a longer span length. Moreover, if it is the same span length, it can be constructed with a smaller crane.

  Compared with the weight of one main girder, the total weight of the plurality of main girder units increases, but the weight per main girder unit is smaller than the main girder weight. As you can see, a long span bridge can be installed with the same crane.

  As a specific example, when construction is performed with one 25-ton rough terrain crane, construction can be performed up to a span length of about 20 m including a floor slab. The main girder unit has suspension points at two locations in the center in the longitudinal direction. It can be installed up to a span length of about 30m. It can be constructed from a floor slab in the range of 20m using a backhoe.

  Since the main girder unit is required to be lighter, a steel material having higher tensile strength is preferable as the span is longer.

  The main girder units are connected in a direction perpendicular to the bridge axis, but the main girder as a set of main girder units is not directly connected but connected by a floor slab support girder installed on the main girder. The connection method may be bolt connection, but a clamp such as a bullman (registered trademark of bullman corporation) may be used simply.

  In addition, when there are a large number of main girder units, it is necessary to adjust the height of the upper part of the main girder unit in order to place the floor slab support girder almost uniformly. In order to solve this problem, an elastic cushioning material such as rubber may be interposed between the main beam and the floor slab support beam.

  Further, in the rapid construction bridge of the present invention, an assembled I-shaped steel having flanges on the upper and lower sides of the web is used as the main girder unit, and the webs or flanges of adjacent main girder units are connected to each other, thereby providing a single main girder. It is good to constitute. In addition, each main girder unit can be used by connecting in the bridge axis direction at the stage of grounding according to the span length.

  The main girder units can be connected to each other with the conventional connection method that joins both the flange and the web. However, since the main girder unit has a narrow interval, sufficient performance can be achieved even when only the web or flange is joined. .

  For example, it can be set as the structure which joins webs via the connection plate installed every several meters in the axial direction of the main girder. A typical installation interval of the connection plate is 1 to 6 m. As a connection method, for example, it is desirable to connect with a bolt connection or a pin, and a joining method considering the construction speed is preferable.

  The main girder units may be joined with a structure in which a connecting member such as a connecting plate is attached in advance to the main girder unit before being suspended by a crane. By doing so, the main girder unit is installed with a crane, and the web or flange is connected with bolts or pins to form a single main girder.

  The main girder spacing may be about the same as the main girder of a conventional bridge (for example, about 2 to 3 m). In the present invention, it is only necessary to insert a tool or a human hand that can be bolted between the main girder units. Therefore, the interval between adjacent flange end portions of the main girder unit is preferably 50 mm or more. If the distance is too far, the coupling between the main girder units is weakened. Therefore, it is preferable that the web interval of the main girder units does not exceed the web height.

  That is, the interval between the main girder units must be within a range in which the connection is effective, and considering the transmission of shearing force, it is not preferable that there is a distance. The web interval below the web height corresponds to the case where the transmission of force between the lower flange and the adjacent upper flange is 45 °. When the web interval is larger than this, the upper flange and the lower flange are joined. Necessary.

  Moreover, the floor slab of the rapid construction bridge of this invention can be comprised by many lining boards laid on the lining board receiving girder as a floor slab receiving girder.

  As the floor slab provided on the floor slab support girder, an RC floor slab or a PC floor slab may be used, but a floor slab can be formed by sequentially installing ready-made lining boards. When the lining plate is used, the weight of the bridge is reduced because it is lighter than the RC floor slab and the PC floor slab, and accordingly, the cross-sectional amount of the main girder supporting the bridge weight can be reduced. As a result, the weight per main girder can be reduced.

  When the span is long, there is a concern that the lining plate girder is greatly bent by the traveling vehicle. In this case, it is desirable to provide a gap between the lining plates so that the lining plates do not contact each other.

  Alternatively, if a compressible material such as a sponge is pasted in the gap between the lining plates in advance, positioning at the time of installation can be facilitated, and the installation time of the lining plates can be shortened. The thickness of the compressible substance interposed between the lining plates is determined by the deformation of the bridge girder, but may be about 50 mm or less.

  The construction method of the rapid construction bridge for constructing the rapid construction bridge of the present invention is that the main girder unit is sequentially constructed by a crane from one main girder receiving portion side on which the main girder is constructed, By connecting the girder units in a direction perpendicular to the bridge axis, a plurality of main girders are formed in parallel between the main girder receiving sections, and all or part of the plurality of floor slab support girder is installed and floor slabs are installed. All or part of the installation is performed.

  In the construction from one side, for the range exceeding the limit by the boom length of the crane, it is preferable to construct the floor slab support girder and install the floor slab from the already installed floor slab.

  For example, it is possible to run on a floor slab where a backhoe has already been installed, and to install a floor slab receiving girder and a floor slab that exceed the limits imposed by the crane boom length.

  Since the rapid construction bridge and its construction method according to the present invention are configured as described above, the following effects can be obtained.

 (1) It is possible to construct a bridge between longer branches with the same crane under the condition that a rapid construction bridge that needs to be installed in a short time such as within a few days is installed from one side using a crane. In addition, since a main girder unit that is lighter in weight than the main girder is used, the number of workers can be reduced.

 (2) Therefore, even when it is difficult to procure personnel and large cranes, such as during disaster recovery, the applicable range of rapid construction bridges will be greatly expanded.

 (3) By unitizing the main girder, the weight of a single member is reduced, making it easier to store and move, and if a slab is used as a floor slab, an emergency such as a disaster Supply in time will be smooth.

It is the schematic perspective view which followed one construction step and showed one embodiment of the rapid construction bridge concerning the present invention. It is a perspective view which shows the member structure of the rapid construction bridge in embodiment of FIG. FIG. 2 is a cross-sectional view in a direction perpendicular to the bridge axis showing an example of a connection structure between main girder units in the embodiment of FIG. 1. It is a perspective view which shows a mode that the main girder unit which attached the connection plate beforehand was lifted with the crane. It is the perspective view which showed the magnitude | size and arrangement | positioning of a lining board exemplarily. It is a top view which shows the positional relationship of the heavy construction machine in Example 1 as a simulation, and the rapid construction bridge constructed. 6 is a process diagram in Example 1. FIG. It is a top view which shows the positional relationship of the heavy construction machine in Example 2 as a simulation, and the rapid construction bridge constructed. 6 is a process diagram in Example 3. FIG. It is a top view which shows the positional relationship of the heavy construction machine in Example 3 as a simulation, and the rapid construction bridge constructed. 6 is a process diagram in Example 3. FIG.

  Hereinafter, specific embodiments of the present invention will be described. Note that the present invention is not limited to the embodiments described below.

  FIG. 1 shows one embodiment of a rapid construction bridge according to the present invention, following construction procedures, FIG. 2 shows its member configuration, and FIG. 3 shows an example of a connection structure between main girder units. .

  In this example, it is a case where a rapid construction bridge is installed between the girder which becomes the main girder receiving part 1 installed on both sides of the river, and the interval between the girder gives the span length. For laying the opposite girder, use cranes, backhoes, human power, etc. according to the situation. Moreover, when the abutment, the pier, etc. which the bridge main body was washed away remain in a healthy state, they can also be utilized.

  The construction procedure is as follows. First, the main girder unit 2a is installed from one side of the river with a crane 11 such as a rough terrain crane. In this example, three main girder units 2a are connected in the horizontal direction, 2 is configured (see FIG. 1 (a)).

  For example, as shown in FIG. 3, the main girder units 2 a can be connected by joining a connecting plate 5 attached to a web between upper and lower flanges by welding or the like with bolts 6. In this example, the connecting plate 5 is joined not only to the web of the main girder unit 2a but also to the upper and lower flanges.

  The connecting plate 5 is attached in advance to the main girder unit 2a before erection, and in this state, the main girder unit 2a is lifted by the crane 11 and installed in the main girder receiving portion 1 as shown in FIG. By making it, construction efficiency can be raised.

  Next, on the main girder 2, the lining plate receiving girder 3 as the floor slab receiving girder intersecting with this is sequentially installed on the main girder 2 and fixed to the main girder 2 with bolts or clamps (see FIG. 1 (b)).

  Then, the rapid construction bridge of this invention is completed by installing the lining board 4 as a floor slab on the lining board receiving girder 3 with the same crane 11 (refer FIG.1 (c)).

  FIG. 5 exemplarily shows the relationship between the size and arrangement of the lining plate.

  The size of the lining plate 4 may be limited by the construction machine, but in order to shorten the construction time, a size larger than the general 1 m × 2 m shown in FIG.

  FIG. 5B shows a case in which a lining plate that is long in the width direction is used. For example, a 2 m × 2 m lining plate 4 a is used for a width of 4 m. In addition, when there are few restrictions of the size of a lining board, various designs, such as 2 sheets of 3 m x 2m in a width direction with respect to 4 m x 2 m of full width and width 6m, for example, can be considered.

  FIG. 5 (c) shows a case where a long lining plate is used in the direction of the lining plate support girder, and a case where a 1 m × 4 m lining plate 4a straddling three lining plate girder is used. is there. In addition, for example, if the gap between the wrapping plate receiving girders is 3 m, use of a lining plate of 3 m × 1 m, 3 m × 2 m, or the like can be considered.

  FIG. 6 shows the positional relationship between the heavy machinery and the rapid construction bridge in Example 1 as a simulation, and FIG. 7 is a process diagram thereof.

  In Example 1, the construction condition is that a connecting main girder bridge as a rapid construction bridge having a span of 20 m and a width of 4 m is constructed with a 25 t rough terrain crane 11 within two days.

  As the main girder unit 2a, 440 × 150 × 9 × 14 SM570 assembled I-shaped steel was used.

  Compared to the conventional case of a single main girder, in the case of the conventional three main girder, the design of one main girder 35579N, in the case of three concatenated main girder consisting of three main girder units, One girder unit is 15294N, and the overall weight is heavy. However, the conventional main girder that is the object to be hung by the crane 11 and the main girder unit according to the present invention greatly reduce the weight and support a larger span length. it can.

In the process chart of FIG.
Dispatch of workers,
Securing the workplace, surveying, positioning,
Equipment / material conveyance,
Girder installation for main girder unit
Unloading main girder unit groundwork,
Main girder unit installation Main girder unit connection Capping plate support girder and capping plate installation
It takes 28 hours to develop the approach section.
Handrail installation,
The construction of the rapid construction bridge is completed in 34 hours.

  FIG. 8 shows the positional relationship between the heavy machinery and the rapid construction bridge in Example 2 as a simulation, and FIG. 9 is a process diagram thereof.

In the first embodiment, the construction condition is that a connecting main girder bridge as a rapid construction bridge having a span of 25 m and a width of 4 m is constructed within 25 days with a 25-ton rough terrain crane 11 and a 0.5 m ² backhoe.

  As the main girder unit 2a, an assembled I-shaped steel made of SM570 having a size of 440 × 150 × 9 × 16 was used.

  Due to restrictions on the capacity of the crane 11, for the section of about 5 m on the opposite shore, the backhoe 12 is run on the lining plate as a floor slab that has already been installed, and the lining plate support girder 3 and the lining plate 4 It was decided to install.

In the process chart of FIG.
Dispatch of workers,
Securing the workplace, surveying, positioning,
Equipment / material conveyance,
Girder installation for main girder unit
Unloading main girder unit groundwork,
Main girder unit installation Main girder unit connection Capping plate support girder and capping plate installation
It takes 30 hours to develop the approach section.
Handrail installation,
The construction of the rapid construction bridge is completed in 36 hours.

  FIG. 10 shows the positional relationship between the heavy machinery and the rapid construction bridge in Example 3 as a simulation, and FIG. 11 is a process diagram thereof.

In Example 1, the construction condition is that a connecting main girder bridge as a rapid construction bridge with a span of 30 m and a width of 6 m is constructed within 25 days with a 25-ton rough terrain crane 11 and a 0.5 m ² backhoe.

  As the main girder unit 2a, a 430 × 150 × 9 × 9 SBHS700 or HITEN780 assembled I-section steel was used.

  Due to the limited capacity of the crane 11, for the section of about 10 m on the opposite shore, the backhoe 12 is run on the lining plate as a floor slab that has already been installed, and the lining plate support girder 3 and the lining plate 4 It was decided to install.

In the process chart of FIG.
Dispatch of workers,
Securing the workplace, surveying, positioning,
Equipment / material conveyance,
Girder installation for main girder unit
Unloading main girder unit groundwork,
Main girder unit installation Main girder unit connection Capping plate support girder and capping plate installation
It takes 36 hours to create an approach section.
Handrail installation,
The construction of the rapid construction bridge is completed in 42 hours.

DESCRIPTION OF SYMBOLS 1 ... Main girder receiving part, 2 ... Main girder, 2a ... Main girder unit, 3 ... Covering plate receiving girder, 4 ... Covering plate, 5 ... Connection plate, 6 ... Bolt,
11 ... Crane, 12 ... Backhoe

Claims (8)

  A plurality of parallel main girders installed between opposing main girder receiving portions for giving a span length; a plurality of floor slab support girders installed at intervals in the bridge axis direction between the plurality of main girders; In a bridge composed of a floor slab installed on a floor slab support girder, the main girder is composed of a plurality of main girder units that can be individually installed between the main girder receiving portions by a crane, and the main girder A rapid construction bridge characterized by ensuring rigidity and bending load resistance as a single main girder by connecting units in a direction perpendicular to the bridge axis.   2. The rapid construction bridge according to claim 1, wherein the main girder unit is an assembled I-shaped steel having flanges on the upper and lower sides of the web, and connects the webs or flanges of adjacent main girder units or both webs and flanges. A rapid construction bridge characterized in that it constitutes a single main girder.   The rapid construction bridge according to claim 1 or 2, wherein a web interval between the main girder units is equal to or less than a web height.   The rapid construction bridge according to any one of claims 1 to 3, wherein an elastic cushioning material for height adjustment is interposed between the floor slab and the main girder.   The rapid construction bridge according to any one of claims 1 to 4, wherein the floor slab is constituted by a large number of lining plates laid on a lining plate receiving girder as the floor slab receiving girder. Characteristic rapid construction bridge.   The rapid construction bridge according to claim 5, wherein a compressible substance is interposed in a gap between the lining plates.   It is a construction method of the rapid construction bridge for constructing the rapid construction bridge according to any one of claims 1 to 6, wherein the main girder is constructed by a crane from one main girder receiving side. The girder units are sequentially installed, and the main girder units are connected to each other in a direction perpendicular to the bridge axis, thereby forming a plurality of main girder in parallel between the main girder receiving portions. A method for constructing a rapid construction bridge, comprising: installing all or a part of the floor slab support girder of the above and all or part of the floor slab.   In the construction method of the rapid construction bridge according to claim 7, for the range exceeding the limit due to the boom length of the crane, the installation of the floor slab support girder and the installation of the floor slab are performed from the already installed floor slab. How to construct a rapid construction bridge.

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