JP2012122305A - Arched bridge cross-linking method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate the need for temporary receiving of an arch girder by a bent.SOLUTION: Attachment parts 20, 20 each provided with an arcuate arch rib base part 21 are constructed on arch abutments 2, 2, respectively, and an arch girder 10 provided with an arcuate arch rib part 11 is lowered between both the attachment parts 20, 20 by a crane C. This work is so set that a clearance w1 is formed between each of both ends 11a, 11a of the arch rib parts 11 and each of both upper ends 21a, 21a of the arch rib base parts 21, 21. A reception part 32 provided in the arch rib part 11 is pressed by axial force transmitting means 30 provided in the arch rib base part 21, and the arch rib part 11 and the arch rib base part 21 are connected together in a state that axial force transmission is possible in an axial direction to construct an arch structure 3. The clearance w1 is set between the arch rib part 11 and the arch rib base part 21, and while the arch girder 10 is suspended by the crane C, the arch rib part 11 and the arch rib base part 21 can be connected together by pressing the reception part 32 by the axial force transmitting means 30. Therefore, the need for temporary receiving of the arch girder 10 by a bent B can be eliminated.

Description

  The present invention relates to a method for bridging an arch bridge.

  There is an arch bridge 1 as a bridge structure constructed across a strait, a lake, a river, a canal, various other natural terrain, or an artificial facility. For example, as shown in the example of FIG. 14, the arch bridge 1 includes, as a main member, an arcuate arch structure 3 that connects between arch abutments 2 and 2 provided on both sides of a bridge point.

  As a construction method of the arch structure 3, for example, there are those described in Patent Documents 1 to 3. In this erection method, the arc-shaped member constituting the arch structure 3 is divided into a plurality of parts along the bridge length direction, and the divided arc-shaped members are sequentially connected. Thus, from both sides of the bridge point, the arch structure 3 is temporarily installed in a cantilever shape toward the center of the span, and the overhang length is gradually extended. Finally, the arch structure 3 connecting the two arch abutments 2 and 2 is constructed by connecting the tips of cantilever-like structures extending from both sides at the center of the span.

  This erection method has a problem that erection takes time because the arc-shaped members constituting the arch structure 3 are bridged while being sequentially connected. Further, in this erection method, the cantilever-like structure must be supported from the arch abut 2 toward the center of the span in the temporary state. There is also the problem of increasing the size.

  For this reason, for example, as described in Patent Document 4, the arch structure 3 manufactured in another place such as a factory (hereinafter referred to as “yard”) is carried into a bridge point, and these are cantilevered. There is also a bridging method in which a crane is used to erection over the entire span without using temporary construction.

  Further, in a long bridge erected in the strait, etc., for example, as shown in FIG. 14, an arch girder 10 manufactured in a yard is used as a bridge point by sea transportation using a carrier ship D equipped with a crane C. In some cases, a method of carrying in is adopted.

  In this bridging method, attachment portions 20 are raised in advance on the arch abutment 2 on both sides of the bridging point. The mounting portion 20 includes an arch rib base portion 21 that constitutes a part of the arch structure 3, and a horizontal stiffening girder base portion 22 in which a road surface is formed when completed. The arch rib base 21 rises from the arch abut 2, extends in an arc shape toward the opposite bank side, and reaches its upper end 21a.

  The arch girder 10 includes an arcuate arch rib portion 11 that constitutes a part of the arch structure 3 and a horizontal stiffening girder portion 12 in which a road surface is formed when completed.

The arch girder 10 is taken down by the crane C between the two mounting portions 20 and 20 facing each other, and is placed on the vent B raised immediately below the bridge point.
Then, by connecting the end portions 11a, 11a on both sides of the arch rib portion 11 of the arch girder 10 placed on the vent B and the upper end 21a of the arch rib base portion 21 of the mounting portion 20, both arch abutments 2, An arch structure 3 connecting the two is constructed.

JP 2010-242316 A (page 3 FIG. 3) Japanese Patent Laying-Open No. 2004-19357 (FIG. 11 on page 13) JP 2003-49409 A (page 1, FIG. 1) JP-T-08-504209 (page 10, Fig. 1 and Fig. 3)

  According to the construction method of the arch bridge using the crane C shown in FIG. 14 described above, the work when the arch girder 10 is taken down between the two attachment portions 20 and 20 becomes a problem.

That is, since the arch girder 10 is suspended by the crane C, the arch girder 10 is shaken during the withdrawal. The length of the arch girder 10 expands and contracts due to temperature changes. The sway width and the amount of expansion / contraction increase as the bridge lengthens. Furthermore, if the crane C is not on land but on the sea, the shaking will be even greater. In addition, the existence of manufacturing errors of members constituting the arch girder 10 and the mounting portion 20 cannot be ignored.
For this reason, if the girder length of the arch girder 10 and the interval between the mounting portions 20 and 20 are set to be the same, the arch girder 10 may not fit exactly between the mounting portions 20 and 20. Moreover, the arch girder 10 may contact the attachment part 20 and may damage a member during the removal.

  Therefore, for example, as shown in the comparative example of FIG. 15, the attachment portion 20 is provided in the position of FIG. 15A set back with respect to the normal position in advance, and after the arch girder 10 is removed, As shown in FIG. 15B, a method of connecting the arch girder 10 and the mounting portions 20 and 20 by advancing the mounting portion 20 that has been set back to a normal position is also conceivable. However, such a setback is often impossible topographically (such as a mountainous area approaching the rear), and in order to make the structure of the huge mounting portion 20 movable, its support structure There is a problem that becomes complicated.

  Therefore, normally, as shown in FIGS. 16 (a) and 16 (b), when the arch girder 10 is removed, a gap w1 in the arch axis direction is formed between the end 11a and the upper end 21a. Is set.

And after taking down the arch girder 10, in order to fill the gap w1, between the ends 11a, 11a on both sides of the arch rib part 11 of the arch girder 10 and the upper end 21a of the arch rib base part 21 of the mounting part 20, Each has an adjustment block A1 interposed.
At this time, the gap w2 between the ends 12a, 12a on both sides of the stiffening girder portion 12 of the arch girder 10 and the tip 22a of the stiffening girder base portion 22 of the mounting portion 20 is also formed. Also, an adjustment block A2 is interposed therebetween.

However, when the installation method using the adjustment blocks A1 and A2 is employed in this way, a vent B for temporarily receiving the arch girder 10 is required between the two attachment portions 20 and 20.
This is because, in a state where the arch girder 10 is suspended from the crane C, the arch girder 10 is shaken, so that the connection with the mounting portion 20 by the adjustment blocks A1 and A2 cannot be performed. Further, in order to cope with the dimensional error of the arch girder 10 and the mounting portion 20 and the expansion / contraction error due to temperature, it is necessary to measure the dimensions of the gaps w1 and w2 and to manufacture the adjustment blocks A1 and A2 based on the dimensions. is there. The dimension measurement of the gaps w1 and w2 cannot be performed in a state where the arch girder 10 is suspended from the crane C.

Providing such a vent B is not preferable because it lengthens the construction process and significantly increases the construction cost.
Furthermore, especially when the vent B is provided on the sea or in a river, there are many time and place restrictions on the provision of the vent B. If it is time when the vent B cannot be provided, the construction process will be further prolonged, and the position where the vent B is allowed to be provided is not symmetrical with respect to the center of the span at the bridge point. This is because the provisionally received arch girder 10 is asymmetrically deformed.

  Accordingly, an object of the present invention is to eliminate the need for provisional support by a vent when bridging an arch bridge.

  In order to solve the above-described problems, the present invention constructs a mounting portion on each opposing arch abut, and each mounting portion extends from the arch abut toward the arch abut on the opposite side and extends to the upper end thereof. An arcuate arch rib base part extending between the two attachment parts, an arch girder provided with an arcuate arch rib part is removed by a crane, both ends of the arch rib part in the arch axis direction, and each arch rib base part In the arch bridge bridging method for constructing an arch structure that connects the arch abuts by connecting the upper ends respectively, when the arch girder is taken down, both ends in the arch axis direction of the arch rib part It is set so that there is a gap in the arch axis direction between the upper ends of the respective arch rib base portions, and an axial force transmission hand is provided on one of the arch girder and the mounting portion. Is provided with a receiving portion on the other side, and after the arch girder is taken down, the axial force transmission means presses the receiving portion in the arch axis direction to thereby connect the arch rib portion and the arch rib base portion to the arch shaft. An arch bridge bridging method characterized in that the arch structure is constructed by connecting in a state where axial force transmission in a direction is possible.

By setting a gap between the arch rib part and the arch rib base part, when the arch girder is taken down, the arch girder and the attachment part can be prevented from hitting. Further, since the axial force transmission means and the receiving portion are provided between the arch girder and the mounting portion, after the arch girder is pulled down, the receiving portion is pressed by the axial force transmission means, and the arch rib portion and the arch rib base portion Can be connected in a state where axial force transmission is possible.
Further, since the arch rib portion and the arch rib base portion can be connected by pressing the receiving portion by the axial force transmission means, this connection can be made even when the arch girder is suspended from the crane. For this reason, the vent for temporarily receiving an arch girder between both attachment parts may be unnecessary.

  Also, conventionally, in order to cope with dimensional errors of the arch girder and mounting part and expansion / contraction errors due to temperature, there is a gap between the arch girder dropped on the vent and the mounting parts provided on both sides of the bridge point. Although the dimension measurement was performed and the adjustment block based on the dimension was manufactured, according to this invention, since the adjustment block is unnecessary, the measurement of the clearance gap performed after taking down an arch girder is unnecessary. Also in this respect, a vent for temporarily receiving the arch girder can be eliminated.

  However, in order to confirm that the structure of the arch girder and the mounting part has been finished with a predetermined accuracy, for example, the arch girder is suspended by a crane in a factory that manufactures the girder in advance, and the girder is in that state. Usually, the length or the like is measured, or the horizontal distance (such as the horizontal distance between the upper ends) between both mounting parts constructed at the bridge point is measured in advance.

  Further, the arch girder is provided with a horizontal stiffening girder part, and both the attachment parts are usually provided with a horizontal stiffening girder base part. The stiffening girder and the stiffening girder base are connected after the arch girder is taken down. For example, in the case of a road bridge, a road surface is formed on the stiffening girder and the stiffening girder base.

Further, as this axial force transmission means, it is only necessary to have a function of connecting the arch rib part and the arch rib base part by pressing the receiving part, for example, using a jack provided with a rod that can be moved forward and backward. A configuration in which the receiving portion is pressed by the rod, or a configuration in which the receiving portion is pressed by the cam member by a rotational movement of the cam member in which the distance from the rotation center gradually changes along the circumferential direction, can be considered.
When the axial force transmission means includes a rod that can advance and retract, specifically, the axial force transmission means includes a rod that can advance and retract in the arch axis direction, and when the arch girder is taken down, the rod The rod is retracted, and after the arch girder is taken down, the rod can be extended to press the receiving portion.

  In each of these configurations, at least one of the two attachment portions is provided with push-up means that pushes up the upper end of the arch rib base, and when the arch girder is taken down, the push-up means pushes up the upper end of the arch rib base. A configuration in which the horizontal distance between the upper ends of the arch rib base portions of the both attachment portions is enlarged, the arch girder is taken down, and then the push-up by the push-up means is released can be adopted.

  The gap between the arch rib part and the arch rib base part is preferably larger in order to prevent the arch girder from coming into contact with the attachment part when the arch girder is taken down. However, if the gap is large, the burden on the axial force transmission means increases. For this reason, when the arch girder is withdrawn, it is effective to increase the horizontal distance between the mounting portions by pushing up the upper end of the arch rib base. According to this method, the gap can be increased when the arch girder is removed, and the gap can be reduced after the arch girder is removed. It is desirable that the push-up means is provided at the attachment portions on both sides.

  Further, in each of these configurations, the arch girder and the mounting part are provided with positioning means, and when the arch girder is taken down, the positioning means moves the arch rib part and the arch rib base part in the vertical direction and the arch axis. It is possible to adopt a configuration in which positioning is performed with respect to a horizontal direction orthogonal to the horizontal direction or any one of the directions.

  The positioning means includes, for example, a pin receiving portion provided in each of the arch girder and the mounting portion, and a pin accommodated between the both pin receiving portions, and the pin is interposed between the both pin receiving portions. By being accommodated, it can be set as the structure which opposes the shear force produced between the said arch rib part and the said arch rib base part.

  Further, as another configuration of the positioning means, for example, a guide member provided on one of the arch girder and the mounting portion and a guide receiving portion provided on the other are provided, and the guide receiving portion The arch rib portion and the arch rib base portion are orthogonal to the arch axis when the guide member hits the guide receiving portion when the arch girder is taken down. It can be set as the structure positioned with respect to a horizontal direction.

  In this invention, a gap is set between the arch rib portion and the arch rib base portion, and the arch rib portion and the arch rib base portion can be connected by pressing the receiving portion by the axial force transmission means while the arch girder is suspended by the crane. As a result, provisional support by venting the arch girder may be unnecessary.

Overall view showing an embodiment of the present invention The whole figure which shows the state which showed the embodiment and finished construction of the structure of an attachment part in a bridge | crosslinking point Overall view of the arch girder shown in the same embodiment and constructed so as to connect both mounting parts Overall view showing the state where the arch girder is lifted by the crane of the trolley and carried to the bridge point Overall view showing the state where the arch girder is withdrawn between both mounting parts Overall view showing a state where the arch part of the arch girder is connected to the arch part of the mounting part Overall view showing the state where the stiffening girder part of the arch girder is connected to the stiffening girder part of the mounting part 4 and 5 show details when lifting the tip of the structure of the mounting portion, (a) is an overall view, (b) is an enlarged view of the main part thereof. 6A and 6B show details when the arch part of the arch girder is connected to the arch part of the attachment part, (a) is a state in the middle of lowering the arch girder, and (b) is the attachment part of the arch girder. (C) is an enlarged view of each main part showing a state in which the arch part of the arch girder and the arch part of the mounting part are connected to each other. (A) (b) (c) is a detailed view of a pulling means used to pull the arch girder and the mounting part together when the arch girder is pulled down between the two mounting parts. The detail of the connection part of an arch girder and an attachment part is shown, (a) is a perspective view before connection of an arch girder and an attachment part, (b) (c) connected the positioning means of the arch girder and the attachment part The perspective view which shows the back, (d) is a perspective view which shows the state after connecting an arch girder and an attachment part by a press means, (e) is a perspective view which shows the cross section of the front-end | tip of the arch part of an attachment part The detail of the front-end | tip of the arch part of an attaching part is shown, (a) is a top view, (b) is a front view, (c) is a right view. The details of the positioning means are shown, (a) is a main part enlarged plan view showing the connected state, (b) is a main part enlarged plan view showing the state before the connection, (c) is before and after the load release of the arch girder Front view comparing conditions Overall view showing a conventional example A comparative example is shown, (a) is an overall view showing a state in which the attachment parts on both sides are set back with respect to the arch girder and temporarily constructed, and (b) is a state where the attachment part is advanced to a normal position and connected to the arch girder. Overall view showing the condition A conventional example is shown, (a) is an overall view showing a state where an arch girder and a mounting part are connected via an adjustment block, and (b) is an enlarged view of a main part thereof.

  Embodiments of the present invention will be described with reference to the drawings. This embodiment relates to a method for bridging an arch bridge 1 constructed across a strait.

  As shown in FIG. 1, the arch bridge 1 carries an arch girder 10 manufactured in a factory into a bridge point using a trolley D equipped with a crane C, and arch abutments 2, 2 on both sides of the bridge point. Are taken down between the mounting portions 20 and 20 respectively raised. And the both ends of the arch girder 10 are connected to each attachment part 20 and 20, the arch structure 3 which connects between the arch abutments 2 and 2 is comprised, and the arch bridge 1 is bridge | crosslinked.

  The configuration of the arch girder 10 includes an arc-shaped arch rib portion 11 constituting a part of the arch structure 3, and a horizontal stiffening girder portion in which a road surface is formed by placing a floor slab at the time of completion. 12. The arch rib part 111 and the stiffening girder part 12 are connected by a number of hangers 13. Each of the arch rib portion 11 and the stiffening girder portion 12 is a box girder composed of upper and lower flanges and webs on both sides.

  The structure of the mounting portion 20 includes an arch rib base portion 21 constituting a part of the arch structure 3 and a horizontal stiffening girder base portion 22 in which a road surface is formed by placing a floor slab at the time of completion. Prepare. The arch rib base 21 rises from the arch abut 2, extends in an arc shape toward the opposite bank side, and reaches its upper end 21a. The arch rib base 21 and the stiffening girder base 22 are connected by a vertical member 23. The rear end of the stiffening girder base 22 (the end far from the center of the span) is supported by a bridge pier 24 raised from the arch abut 2. Each of the arch rib base 21 and the stiffening girder base 22 is a box girder composed of upper and lower flanges and webs on both sides.

  The bridging method of the arch bridge 1 will be described in order. First, as shown in FIG. 2, the attachment portions 20 and 20 are constructed on the opposing arch abutments 2 and 2, respectively. The upper end 21a of the arch rib base 21 is supported by a temporary cradle 26 raised from the ground in front of the arch abut 2 (the side closer to the center of the span). The temporary cradle 26 includes a jack as a push-up means 25 at the upper end. The push-up means 25 can push up the upper end 21 a of the arch rib base 21. As this jack, for example, a hydraulic jack can be used.

  As shown in FIG. 3, the arch girder 10 manufactured in the yard is carried into a bridge point by a trolley D equipped with a crane C. The arch girder 10 is withdrawn between the attachment parts 20 on both sides of the bridge point.

  In the yard, a suspension test using a crane is performed in advance, and the length of the arch girder 10 in the suspended state is measured. Both attachment parts 20 and 20 are constructed at appropriate positions based on the measured digit length.

That is, as shown in FIG. 9 (b), the appropriate position is that when the arch girder 10 is pulled down, both end portions 11a, 11a in the arch axis direction of the arch rib portion 11 and the respective arch rib base portions 21 are used. , 21 is set to have a gap w1 in the arch axis direction between the upper ends 21a, 21a.
Further, as shown in FIGS. 9 (a) and 9 (b), between the ends 12a, 12a of the stiffening girder portion 12 in the bridge axis direction and the tips 22a, 22a of the stiffening girder base portions 22, 22, respectively. It is set so that a gap w2 in the bridge axis direction is formed.
The arch girder 10 can be withdrawn without interfering with both attachment portions 20 and 20 by the interposition of the gaps w1 and w2.

  Moreover, in this embodiment, since both the attachment parts 20 and 20 are each provided with the pushing-up means 25, when removing the arch girder 10, as shown to a solid line from a broken line to Fig.8 (a) (b). The push-up means 25 can push up the upper end 21a of the arch rib base 21. By this pushing up, the upper end 21a of the arch rib base 21 is retracted by a distance L3 in the bridge axis direction. For this reason, since the horizontal distance between the upper ends 21a and 21a of the arch rib bases 21 and 21 of both the attachment parts 20 and 20 increases from L1 to L2 in the figure, the separation between the arch girder 10 and the attachment part 20 is large. Thus, the arch girder 10 can be removed more safely.

  FIG. 4 shows the state of the withdrawal. Since the arch girder 10 is not temporarily received by the vent B as in the prior art, the suspended arch girder 10 has a merit that the deformation of the member due to the suspension can be symmetrical with respect to the center of the span. is there.

  After the arch girder 10 is removed, the push-up means 25 releases the push-up of the arch rib bases 21 and 21, and the upper end 21a of the arch rib base 21 is originally from the broken line to the solid line in FIG. It will return to the position.

  In this embodiment, when pulling down the arch girder 10, the first pulling means 60 and the second pulling means 70 shown in FIG. 10A are used.

  The first pulling means 60 has a wire 61a connected to the fixing portion 63 provided in the stiffening beam portion 12 of the arch beam 10, and is connected to a connecting member 67 as shown in FIG. Further, another wire 61 b is connected to the fixing portion 62 provided on the stiffening girder base portion 22 of the mounting portion 20, and the wire 61 b is connected to a fixed pulley 66 a connected to the fixing portion 65 and a connecting member 67. It is wound around the movable pulley 66b alternately and connected to the winch 64. When the winch 64 is operated, the wire 61b is pulled by the driving force, and the arch girder 10 is drawn toward the mounting portion 20 via the movable pulley 66b, the connecting member 67, and the wire 61a.

  The second pulling means 70 has a wire 71a connected to a fixing portion 73 provided on the arch rib portion 11 of the arch girder 10, and is connected to a connecting member 77 as shown in FIG. Further, another wire 71 b is connected to the fixing portion 72 provided on the arch rib base portion 21 of the mounting portion 20, and the wire 71 b is connected to the fixed pulley 76 a connected to the fixing portion 75 and the moving pulley connected to the connecting member 77. It is alternately wound around 76b and connected to the winch 74. Furthermore, another wire 71c branches from the wire 71a and is connected to a winch (not shown) provided on the land side. Reference numerals 78, 79a, 79b, and 79c in the figure are fixing portions. When the winch 74 is operated, the wire 71b is pulled by the driving force, and the arch girder 10 is drawn toward the mounting portion 20 via the movable pulley 76b, the connecting member 77, and the wire 71a. At the same time, if the land-side winch is operated, the wire 71c and the wire 71a are drawn.

  Next, both ends 11a and 11a of the arch rib part 11 in the arch axis direction are connected to the upper ends 21a and 21a of the arch rib base parts 21 and 21, respectively.

  Accurate positioning of the arch girder 10 and the mounting portion 20 is performed by positioning means 40 and 50 provided in the arch girder 10 and the mounting portion 20. The positioning means 40 and 50 each have a function of positioning the arch rib portion 11 and the arch rib base portion 21 with respect to the vertical direction and the horizontal direction orthogonal to the arch axis.

  The positioning means 40 (hereinafter referred to as “first positioning means 40”) is accommodated between the pin receiving portions 41 and 42 provided on the arch girder 10 and the mounting portion 20 respectively, and between the pin receiving portions 41 and 42. Pin 43 is provided. The pin 43 can advance and retreat in the arch axis direction by the function of the jack 44 disposed on the rear side. In this embodiment, a hydraulic jack is adopted as the jack 44. Further, the positioning means 40 is provided at one place along each of the webs on both sides of the arch rib portion 11 and the arch rib base portion 21.

  When the arch girder 10 is withdrawn, the pin 43 is accommodated between the pin receiving portions 41 and 42 at a timing when the arch rib portion 11 and the arch rib base portion 21 face each other. Thereby, the arch rib part 11 and the arch rib base part 21 can be positioned and can counter the shearing force generated between the arch rib part 11 and the arch rib base part 21.

  FIGS. 11A to 11D show a state of alignment between the arch rib portion 11 and the arch rib base portion 21 by the first positioning means 40. 12 and 13 are detailed views showing the configuration of the first positioning means 40. FIG.

  In this embodiment, the pin receiving portions 41 and 42 are constituted by through holes extending in the arch axis direction, and the pins 43 are fitted in both through holes in a state where the axial centers of both through holes are aligned on the same straight line. It comes to fit.

  The tip of the pin 43 is narrowed in a taper shape, so that it becomes a so-called bullet-shaped punch, so that it can easily enter the pin receiving portions 41 and 42. Further, the pin receiving portion 42 on the arch rib portion 11 side is narrowed in a tapered shape as the shape of the through hole is directed toward the center of the span. Since the tapered outer surface at the tip of the pin 43 is in surface contact with the entire tapered inner surface, the function of preventing the pin 43 from coming off is exhibited.

The configuration of the pin receiving portions 41 and 42 is not necessarily limited to the hole as in this embodiment. For example, the pin receiving portions 41 and 42 may be a concave portion or the like that is partially open in the circumferential direction, but at least the pin 43 is accommodated. Therefore, it is necessary that the pin 43 is firmly fixed so that the arch rib portion 11 and the arch rib base portion 21 can be positioned.
Further, it is desirable that shear force can be transmitted between the arch rib portion 11 and the arch rib base portion 21. For example, as shown in FIG. 13C, even when the arch rib portion 11 and the arch rib base portion 21 are bent (not aligned) with respect to the arch axis direction, the pin 43 is pin receiving portions 41 and 42. It is desirable to have a configuration that does not leave.

  Further, the positioning means 50 (hereinafter referred to as “second positioning means 50”) includes a guide receiving portion 51 provided on one of the arch girder 10 and the mounting portion 20, and a guide member 52 provided on the other. ing. In this embodiment, the guide member 52 is the outer surface of the web of the arch rib portion 11, but the guide member 52 may be another member protruding from the web in the arch axis direction or in the horizontal direction perpendicular to the arch axis.

  As shown in FIGS. 11 (e) and 12 (c), the guide receiving portion 51 includes inclined plates 51 a that gradually spread outward on both sides of the web of the arch rib base portion 21. The inclined plate 51a is reinforced with ribs 51b. The distance between the inclined plates 51a and 51a on both sides is desirably slightly larger than the distance between the web outer surfaces on both sides of the arch rib portion 11 at the lowest position (near the lower flange of the arch rib portion 11).

  When the arch girder 10 is taken down by the second positioning means 50, the guide member 52 hits the inclined plates 51a on both sides, thereby positioning the arch rib portion 11 and the arch rib base portion 21 in the horizontal direction perpendicular to the arch axis. can do. For this reason, the positioning operation by the first positioning means 40 is simple. That is, the function of the second positioning means 50 makes it easy to align the axial centers of the through holes of the pin receiving portions 41 and 42 in a state of being close to a straight line, and thereafter, the pin 43 is received in the pin receiving portions 41 and 42. Easy to work.

  In this embodiment, the guide receiving portion 51 is provided on the mounting portion 20 side, and the guide member 52 is provided on the arch girder 10 side. However, it is possible to arrange them in reverse.

  Moreover, after suppressing the swaying of the arch girder 10 by the first positioning means 40, the arch rib part 11 and the arch rib base part 21 may be connected by a temporary attachment plate (not shown). This temporary attachment plate functions as a departure prevention device and is provided so as to span a portion that does not interfere with the first positioning means 40 and the second positioning means 50, for example, the web of the arch rib portion 11 and the web of the arch rib base portion 21. be able to.

  Bolt holes are respectively formed in the web of the arch rib portion 11 and the web of the arch rib base portion 21, and the bolt holes provided in the respective webs are aligned with the bolt holes provided in the temporary attachment plate. Insert the bolt into the combined bolt hole and tighten the nut. This tightening can be performed by placing an operator inside and outside the box girder constituting the arch rib portion 11 and the arch rib base portion 21. The shearing force between the web of the arch rib portion 11 and the arch rib base portion 21 can be transmitted through the temporary attachment plate.

  For this reason, if there is a deformation of the joint angle beyond the plan (a state in which the arch rib part 11 and the arch rib base part 21 are bent with respect to the arch axis direction) due to manufacturing error, excessive deformation, etc., the pin 43 However, in this case, the temporary attachment plate can replace the function of the first positioning means 40.

  In addition, it is desirable that either one of the bolt hole provided in each web and the bolt hole provided in the temporary attachment plate is a long hole extending in the arch axis direction. In addition, the temporary attachment plate may be rotatably attached to the web by a rotation axis orthogonal to the outer surface of the web. When connecting the temporary attachment plate, the temporary attachment plate can be aligned at a predetermined position by rotating the temporary attachment plate around the rotation axis along the outer surface of the web.

  Next, the axial force transmission means 30 connects the arch rib portion 11 and the arch rib base portion 21 to a state in which axial force transmission in the arch axis direction is possible.

As shown in FIG. 11, an axial force transmission means 30 is provided on the arch rib base portion 21 of the mounting portion 20, and a receiving portion 32 is provided on the arch rib portion 11 of the arch girder 10. The axial force transmission means 30 is constituted by a hydraulic jack 31 provided with a rod 31a that can advance and retract in the arch axis direction.
In this embodiment, the axial force transmission means 30 and the receiving portion 32 are provided in two sets on the upper flange side and two sets on the lower flange side of the box girder constituting the arch rib base portion 21 and the arch rib portion 11. The number can be appropriately increased or decreased according to the design load.

  When the arch girder 10 is taken down, the rod 31a is retracted as shown in FIGS.

  After the arch girder 10 is taken down, the rod 31a is extended by the hydraulic function, thereby pressing the receiving portion 32 with the rod 31a as shown in FIG. 10 (d). The rod 31a presses the receiving portion 32 in the arch axis direction, thereby connecting the arch rib portion 11 and the arch rib base portion 21 to a state in which axial force transmission in the arch axis direction is possible (see FIG. 9C). Thereby, the arch structure 3 which connects between both arch abuts 2 and 2 can be constructed | assembled (refer FIG. 5). A symbol J in the figure indicates a connection portion between the arch rib portion 11 and the arch rib base portion 21.

  At this time, a liner material may be inserted between the tip of the rod 31 a and the receiving portion 32. The liner material can increase the degree of close contact between the tip of the rod 31a and the receiving portion 32, or can compensate for the shortage of stroke if the stroke of the rod 31a is insufficient.

  In this embodiment, the axial force transmission means 30 is provided on the mounting portion 20 side, and the receiving portion 32 is provided on the arch girder 10 side. However, it is possible to arrange them in reverse. However, it is desirable to provide the axial force transmission means 30 on the mounting portion 20 side.

Thereafter, the arch girder 10 is released from the suspended state by the crane C, and the arch rib base 21 constituted by the box girder and the arch rib part 11 are connected by an attachment plate (not shown).
The connection by the attachment plate is provided on the upper and lower flanges and the web by spanning the attachment plate across the upper flanges, the lower flanges, the webs on both sides, or the vertical ribs inside the box girder. After aligning the bolt hole and the bolt hole provided in the attachment plate, the bolt is inserted into the aligned bolt hole to tighten the nut. This tightening can be performed by placing an operator inside and outside the box girder constituting the arch rib portion 11 and the arch rib base portion 21.

  After the connection by the attachment plate, all of the first positioning means 40, the second positioning means 50, the axial force transmission means 30, and the receiving portion 32 can be removed.

  After the arch structure 3 is constructed, the temporary support 26 and the push-up means 25 are removed as shown in FIG. Then, as shown in FIG. 7, the adjustment corresponding to the gap w <b> 2 between the end portions 12 a and 12 a on both sides of the stiffening girder portion 12 of the arch girder 10 and the tip 22 a of the stiffening girder base portion 22 of the mounting portion 20. The block A2 is carried in, the stiffening girder part 12 and the stiffening girder base part 22 are connected by the adjustment block A2, and the bridge of the arch bridge 1 is terminated except for incidental work such as road surface paving.

  By adopting the bridge method of the arch bridge 1 as described above, the axial force transmission means 30 and the receiving portion 32 are arranged between the arch rib base portion 21 and the arch rib portion 11 as shown by an arrow a in FIG. Can handle power transmission. Further, the axial force transmission means 30 and the receiving portion 32 can also handle transmission of moment and torque due to couple resistance between the axial force transmission means 30 and the receiving portion 32, as shown by an arrow b in FIG. it can. Further, the pin 43 and the pin receiving portions 41 and 42 constituting the positioning means 40 can take charge of transmission of the shearing force between the arch rib base portion 21 and the arch rib portion 11.

  That is, in the connection portion J between the arch rib base portion 21 of the mounting portion 20 and the arch rib portion 11 of the arch girder 10, when a positive bending moment is transmitted, a tensile force acts on the lower flange side and a compressive force acts on the upper flange side. It is common. In the case of the arch bridge 1 according to the present invention, since the bending moment is very small with respect to the axial force (compression), even if the moment acts, the tensile stress hardly acts. Therefore, moment connection becomes possible by making the joint portion (the connecting portion J) a metal touch structure. However, if the joint part has a metal touch structure, the construction error cannot be absorbed even if the accuracy can be secured at the time of manufacture.

  For this reason, by disposing the axial force transmission means 30 and the receiving portion 32 at the four corners of the joint, the moment force connection between the arch rib base 21 and the arch rib portion 11 is achieved by the axial force transmission means 30 and the receiving portion 32. Is to do. Further, the shearing force transmitting means (the positioning device 40) also used as a guide device can be used to transmit the shearing force.

  Thus, the gap w1 is set between the arch rib base 21 and the arch rib part 11, and the arch rib base 21 and the arch rib part 11 can be connected by pressing the receiving part 32 by the axial force transmitting means 30. The provisional provision by the vent B of the arch girder 10 is eliminated.

  In addition, the bridge | crosslinking method of the arch bridge 1 of this invention can be employ | adopted also in what kind of arch bridge structure, For example, in addition to the Nielsen Rose bridge of this embodiment, it can be employ | adopted also in Rose bridge and Langer bridge. It can also be used in arch bridges other than steel structures.

DESCRIPTION OF SYMBOLS 1 Arch bridge 2 Archabat 3 Arch structure 10 Arch girder 11 Arch rib part 11a End part 12 Stiffening girder part 12a End part 20 Mounting part 21 Arch rib base part 21a Upper end 22 Stiffening girder base part 22a Tip 30 Axial force transmission means 31 Jack 31a Rod 32 Receiving part 40 Positioning means 41, 42 Pin receiving part 43 Pin 50 Positioning means 51 Guide receiving part 51a Inclined plate 52 Guide member 60 First attracting means 70 Second attracting means A1, A2 Adjustment block B Vent C Crane D w1, w2 gap

Claims (6)

Mounting portions (20, 20) are respectively constructed on the opposing arch abutments (2, 2), and each of the mounting portions (20, 20) rises from the arch abutment (2) and the arch abutment (2) on the opposite side. An arch girder (10) having an arcuate arch rib base (21) extending toward the upper end (21a) and having an arcuate arch rib (11) between the attachment parts (20, 20). ) With the crane (C), and both the end portions (11a, 11a) of the arch rib portion (11) in the arch axis direction and the upper ends (21a, 21a) of the arch rib base portions (21, 21), respectively. In the bridging method of the arch bridge that constructs the arch structure (3) that connects the arch abutments (2, 2) by connecting,
When the arch girder (10) is withdrawn, both ends (11a, 11a) of the arch rib part (11) in the arch axis direction and upper ends (21a, 21a) of the arch rib base parts (21, 21) A gap (w1) in the arch axis direction is formed between the arch girder (10) and the mounting portion (20), and an axial force transmitting means (30) is provided on the other side and a receiving portion (32). After the arch girder (10) is withdrawn, the axial force transmission means (30) presses the receiving part (32) in the arch axis direction to thereby form the arch rib part (11). A method for bridging an arch bridge, wherein the arch structure (3) is constructed by connecting the arch rib base (21) to a state capable of transmitting an axial force in the arch axis direction.   The axial force transmission means (30) includes a rod (31a) that can advance and retract in the direction of the arch axis. When the arch girder (10) is taken down, the rod (31a) is retracted, and the arch girder (10 The method according to claim 1, wherein the rod (31 a) is extended to press the receiving portion (32) after the) is removed.   At least one of the both attachment parts (20, 20) is provided with push-up means (25) for pushing up the upper end (21a) of the arch rib base part (21), and when the arch girder (10) is taken down, the push-up means (25) pushes up the upper end (21a) of the arch rib base (21), thereby increasing the horizontal distance between the upper ends (21a, 21a) of the arch rib base (21, 21) of the both attachment portions (20, 20). 3. The method of bridging an arch bridge according to claim 1 or 2, wherein the arch bridge (10) is lifted and then lifted by the push-up means (25) is released.   Positioning means (40, 50) is provided on the arch girder (10) and the attachment part (20), and when the arch girder (10) is taken down, the positioning means (40, 50) is arranged to be the arch rib part. (11) and the said arch rib base (21) are positioned with respect to the up-down direction and the horizontal direction orthogonal to the arch axis, or any one of them. The bridge method of the arch bridge as described in 2.   The positioning means (40) is accommodated between the pin receiving portions (41, 42) provided in the arch girder (10) and the mounting portion (20), respectively, and both pin receiving portions (41, 42). Pin (43), and by accommodating the pin (43) between the pin receiving portions (41, 42), the arch rib portion (11) and the arch rib base portion (21) The method for bridging an arch bridge according to claim 4, wherein the method counteracts a shearing force generated therebetween.   The positioning means (50) includes a guide member (52) provided on one of the arch girder (10) and the attachment part (20) and a guide receiving part (51) provided on the other, The guide receiving portion (51) is formed so as to gradually expand outward toward the upper side, and when the arch girder (10) is taken down, the guide member (52) is moved to the guide receiving portion (51). 6. The method of bridging an arch bridge according to claim 4, wherein the arch rib portion (11) and the arch rib base portion (21) are positioned with respect to a horizontal direction orthogonal to the arch axis.

Images