JP2018009385A - Steel deck structure joining longitudinal rib and deck plate by one-sided bolt - Google Patents

Abstract

PROBLEM TO BE SOLVED: To fundamentally solve problems of fatigue cracks of a weld joint for joining a deck plate of a steel deck and a web of a closed section longitudinal rib, and the weld joint for joining the web of both members in a crossing position between the longitudinal rib and the transverse rib, in a conventional bridge, and thereby eliminate the need for repair.SOLUTION: A steel deck 1 has a deck plate 10 and a closed section longitudinal rib 20. The longitudinal rib 20 has a lower flange 25, a web 26 of both sides, and a mounting flange 27 formed outwardly in the bridge axis perpendicular direction (left and right directions of Fig. 1) from an upper end of each web 26. The mounting flange 27 and the deck plate 10 are subjected to bearing connection in which tapping bolts 30 are tightened from the mounting flange 27 to the deck plate 10 to prepared holes 28, 14 and are made to proceed while threading by oneself, and a female screw is formed by plastic deformation. In the crossing position, a connecting member 50 and a tapping bolt 55 for crossing position are used to perform the bearing connection (Fig. 11).SELECTED DRAWING: Figure 1

Description

  The present invention relates to a steel slab of a bridge such as a steel bridge, and more particularly to a steel slab structure in which vertical ribs and a deck plate are joined with one-side bolts.

  Regarding the terminology in the present specification, the term “tapping bolt” refers to a thread that is threaded by screwing directly into a pilot hole that is not subjected to female threading in at least one of a plurality of members to be joined. Bolts or screws that are screw-bonded by forming a female screw by plastic deformation, and that advance while being threaded by themselves, and that are formed by elastic deformation or by cutting, so that the screw or screw is screw-joined. including. The “tapping bolt” should be interpreted as a concept including a thread rolling screw (abbreviated as TRS (registered trademark)), a thread forming screw, a tapping screw, a tap bolt, and the like.

  The term “one-side bolt” should be interpreted as a concept that includes bolts or screws that, for example, tapping bolts, etc., that join or frictionally join a plurality of members to be joined by construction from one side. Don't be.

  The vertical direction is the direction seen from the ground in the bridge where the steel deck is constructed, and the vertical direction only in the drawing indicates the drawing.

  Conventionally, steel slabs as bridge floors are lightweight, easy to erection, and can be installed quickly, so there is a need for bridges with long span lengths, bridges built on soft ground, or shortening the construction period. It has been favorably adopted by many bridges in the city, such as the bridge that can be used.

  Conventional typical steel slabs pose major problems related to safety and repair due to fatigue cracks in the welded joints. The steel slab is constructed by welding the upper end of a web of a closed cross-section longitudinal trough rib that extends along the longitudinal direction, which is the bridge axis direction, to the lower surface of the deck plate by continuous fillet welding. Recently, many fatigue cracks called bead penetration cracks that break the weld metal to be welded and joined in the steel slab, and many fatigue cracks called deck penetration cracks that have penetrated from the weld to the deck plate have been discovered. Fatigue countermeasures for existing steel slabs are important in managing bridges on roads. These cracks are initially very small and difficult to visually recognize. They also occur in difficult-to-view parts, and the cracks become considerably long, resulting in rusting or significant pavement damage or deformation. Otherwise, it is difficult to find.

  Therefore, in the newly installed steel deck using vertical ribs with closed cross section, in order to improve the fatigue durability in response to the cracks through the deck, the road bridge specification revised in 2012 is the deck plate at the wheel load position. The minimum plate thickness was redefined from 12 mm to 16 mm. Therefore, there is a problem that the dead load of the bridge increases.

  In another conventional technique, the rigidity of the slab is ensured by a steel fiber reinforced concrete (abbreviated as SFRC) in order to suppress the occurrence and progress of fatigue cracks in the weld metal. On the upper surface of the deck plate to which the vertical ribs are welded and stiffened, a large number of stud gibbles for preventing slippage are erected, the SFRC pavement is joined by an adhesive, and the surface layer is subjected to asphalt pavement ( Non-patent documents 1, 2). The steel floor slab of this conventional SFRC pavement uses stud gibber and adhesives, so it is not only inferior in workability but also difficult to peel and remove the pavement during renewal repair, requiring a lot of labor and time There is a problem that.

  Fatigue cracks of the weld metal in the existing steel slab are detected by, for example, flaw detection by electromagnetic induction and ultrasonic waves (Patent Document 1), and repairs the fatigue cracks of the weld metal generated and detected in the existing steel slab. One certain construction method is disclosed in Patent Document 2, for example. For repairing cracks, after peeling the asphalt pavement on the deck plate, a corrugated plate with continuous irregularities is placed, and the deck plate is inserted into the bolt insertion hole formed between the trough of the corrugated plate and the deck plate. Bolts are inserted from below, nuts are tightened above the deck plate, and the corrugated plate is fixed by friction welding, and concrete is placed in the space between the deck plate and the corrugated plate from the hole formed in the corrugated plate. Recover by paving asphalt on top.

  In this conventional repair method, repair work must be performed simultaneously from both the top and bottom of the deck plate, so traffic regulation during work is necessary, workability is inferior, and cracks are repaired even if the asphalt pavement is healthy. It must be peeled off. As a result, there is a problem that much labor and time are required for inspection maintenance and maintenance for the fatigue crack of the weld metal. Accordingly, there is a demand for the appearance of a steel slab that eliminates the occurrence and progress of the fatigue cracks from the root and does not need to be repaired.

Murakoshi et al .: Experimental study on structure and durability evaluation of reinforcing method by SFRC pavement of existing steel slab, JSCE A1, Vol. 69, no. 3, pp. 416-428, 2013 (Germany) Civil Engineering Research Laboratories, etc .: Joint research on fatigue durability improvement technology for steel deck slab bridges (Part 2, 3, 4) report, design and construction manual (draft) on reinforcement of existing steel decks by SFRC pavement, Joint Research Report, No. 395, 2009

JP 2010-133835 JP 2005-256462 A

  An object of the present invention is to provide a steel slab that can eliminate the above-mentioned problems of a conventional new steel slab, ensure high quality, and facilitate inspection maintenance and maintenance over a long period of time. is there.

The present invention
(A) Deck plate 10,
(B) a closed cross-section vertical rib 20 that stiffens the deck plate 10;
A longitudinal rib body 23 that forms a closed space extending in the bridge axis direction together with the lower surface of the deck plate 10, and an upper end portion 24 of the longitudinal rib body 23 that is formed outwardly in the direction perpendicular to the bridge axis. (C) the cross-sectional longitudinal ribs 20 having mounting flanges 27 arranged at a position; 27 is a steel slab 1 including a tapping bolt 30 for bearing and supporting 27.

  According to the present invention, in a steel floor slab of a bridge such as a steel bridge, a mounting flange of a closed cross-section vertical rib is supported and joined by a tapping bolt that is a bearing joint bolt on the lower surface of the deck plate, and the deck plate is stiffened. Is done. In the present invention, since there is no welded joint for joining the deck plate and the longitudinal rib in the conventional steel slab, the bead penetration crack and the deck penetration crack do not occur, and the above-mentioned problem caused by the fatigue crack is caused from the root. It is wiped out, and the long-term fatigue durability of the steel slab is improved, no repair is required, and a new and innovative steel slab that facilitates long-term inspection and maintenance is realized.

  The steel slab of the present invention is constructed by stiffening a deck plate with vertical ribs and horizontal ribs and pavement. Steel slabs are supported by floor groups such as vertical and horizontal girders, or main girders and main structures. A horizontal rib can also be used as a cross beam of a floor set. The main structure of the structural elements of girder bridges is typically a vertical girder in the I-girder (plate girder) format, which receives the load from the horizontal ribs in the vertical girder, and a main girder in the box girder format. The main girder transmits the load to the substructure via the bearing. The deck plate of the steel deck according to the present invention may constitute the upper flange of these main girders. The steel slab of the present invention can also be used as a floor for a truss bridge. The steel deck of the present invention can be implemented in connection with such and other structural types of bridges.

  According to the present invention, since there is no weld joint from the beginning, there is no stress concentration, welding defects, residual stress that greatly affect the fatigue damage of the weld joint, fatigue crack propagation to the deck plate is eliminated, and fatigue durability It is easy to ensure high quality such as improvement of the quality. Therefore, the minimum plate thickness of the deck plate at the wheel load position can be reduced, for example, 12 mm before the revision of the specification, which is thinner than 16 mm defined in the above-mentioned road bridge specification, or less. Further, the above-described SFRC pavement is not necessary. Thus, the fatigue problem of the steel slab can be fundamentally solved and the dead load can be greatly reduced.

  Therefore, structural elements of the bridge, for example, a floor set, a main girder, a main structure, and a lower structure can be simplified. When bridge reinforcement such as seismic reinforcement according to the new standard is necessary for bridges with reduced load bearing capacity, reinforcement is achieved by replacing heavy reinforced concrete slabs, prestressed concrete slabs, etc. with steel slabs of the present invention. It is unnecessary or the reinforcing range can be reduced.

  Since the steel slab of the present invention is lighter than a reinforced concrete slab, etc., even when the road surface is widened, the reinforcement of the existing main girder is unnecessary or the range of reinforcement can be reduced.

  In order to manufacture the steel floor slab of the present invention, at the factory, for example, when the deck plate is installed horizontally, the work such as drilling of the pilot hole for supporting bearing joining and tightening of the tapping bolt is performed on the upper surface. However, it can be performed by downward construction, and the workability is good. The upper surface of the deck plate at the time of manufacture is inverted to be the lower surface when used as a bridge floor, and is upside down between the time of manufacturing and the used state.

  In the embodiment of the present invention, for example, in the embodiment of the present invention, the support pressure bonding pilot hole has a right cylindrical shape having a uniform circular cross section in the axial direction as shown in FIG. A plurality of bearing holes for supporting bearings are formed in advance by cutting blades of a drill tool such as a drilling machine in rows at equal intervals in the bridge axis direction on the mounting flange. The blade of the drill tool is guided by the support flange joining pilot holes of the mounting flange, and the corresponding support joint joining pilot holes are formed in the deck plate in pairs. As a result, the pilot holes forming a plurality of pairs in the mounting flange and the deck plate have the same inner diameter and have axes on a common straight line. Therefore, the tapping bolt is tightened and advanced from the mounting flange to the deck plate, and the tapping bolt is advanced while threading itself to form a female thread by plastic deformation.

  In this way, the steel floor slab can be manufactured with high accuracy by being applied at an accurate position, and the manufacturing workability is good. Even if the tapping bolt is mistakenly applied at the time of manufacture, the bolt can be removed and re-execution is easier than welding. In the present invention, welding work requiring high quality control is unnecessary, and therefore, work for correcting deformation due to welding heat and work associated with welding such as inspection or repair of welding flaws are also unnecessary. Simplification of the manufacturing process can be expected.

  In another embodiment of the present invention, as shown in FIG. 22, female thread holes, which are pilot holes for bearing joints, are provided in advance at intervals along the plurality of bridge axis directions on the mounting flange and the deck plate. Each is formed by engraving. The tucking bolt may be screwed into these female screw holes to achieve support bearing joining between the deck plate and the mounting flange.

  Since the bearing support joining between the deck plate and the mounting flange can be achieved by tapping bolts, unlike the high-strength bolts, joining without loosening is possible. Repairs associated with steel deck staking bolts are not required over a long period of time. Moreover, the periodic inspection of whether or not the tapping bolt is loosened due to the use of the steel deck for a long period of time is easy, for example, by visual observation from the outside, as will be described later with reference to FIG.

  Since the tapping bolt faces below the steel slab, operations such as inspection and maintenance of the steel slab and maintenance can be performed only below the steel slab. Even if it is necessary to remove or replace the tapping bolts and vertical ribs at the time of repair, or remove the tapping bolts that have been used so far, a new pilot hole for bearing support with a larger inner diameter will be created. Even if it becomes necessary to drill and screw in a new large-diameter tapping bolt to make a new bearing support, all these operations can be performed only under the steel deck. No repair work is required above the deck deck plate. Therefore, traffic regulation is unnecessary, and for repairs related to tapping bolts, there is no need to peel off pavement such as healthy asphalt on the deck plate, and the time required for repair work can be shortened, Cost can be reduced.

  According to the support welding, compared with the friction welding, the pressure contact force between the deck plate and the mounting flange of the vertical rib due to the high axial force of the tapping bolt is not required. In such bearing support, the steel plate thickness is small, so the axial length of the female screw into which the tapping bolt is screwed is relatively short, and the high axial force required for frictional connection between the deck plate and the mounting flange is obtained. Even if it cannot be achieved or there is no axial force, it can be reliably achieved. According to the support joint, it is not necessary to manage the friction coefficient between the bottom surface of the deck plate and the top surface of the mounting flange by a rust preventive paint, and the manufacturing can be simplified. The necessary supporting pressure depends on the outer diameter of the tapping bolt, and the number of necessary tapping bolts can be reduced by increasing the bolt diameter. Since the bearing support joining is completed by screwing in the tapping bolt and the desired bearing strength can be obtained, the manufacturing work of the steel deck can be simplified also from this viewpoint. Even if the deck plate itself or the surface of the deck plate has irregularities, it is easy to reliably achieve bearing support by tapping bolts.

  The vertical rib may be a closed cross-section rib or an open cross-section rib having a web extending downward from the attachment flange. Deck plates, vertical ribs, etc. are made of structural steel. The tapping bolt may be made of high-strength steel such as a high-strength bolt, but may be made of other materials.

The present invention
The vertical rib body 23 of the closed cross-section vertical rib 20 is:
A lower flange 25, and a web 26 that rises from both sides of the lower flange 25,
The mounting flange 27 is formed outwardly in a direction perpendicular to the bridge axis, connected to the upper end of each web 26.

The present invention
A closed cross-section vertical rib 20 for stiffening the deck plate 10,
Lower flange 25,
A web 26 that rises up on both sides of the lower flange 25, and an attachment flange 27 that is formed on the lower surface of the deck plate 10 and that is formed outwardly from the upper end of each web 26;
The lower flange 25 and the web 26 form a closed space 22 together with the lower surface of the deck plate 10,
The deck plate 10 and the mounting flange 27 are closed-section vertical ribs characterized by being bolted.

  According to the present invention, the vertical rib main body of the vertical rib may have a U trough shape in which the lower flange and the webs on both sides thereof are U-shaped, the lower flange is flat, for example, has an inverted trapezoidal cross-sectional shape. However, it may have another closed cross-sectional shape (FIG. 24 (1)) and may not have a lower flange (FIG. 24 (2), FIG. 24 (3)).

The present invention
The tapping bolt 30 is
It is characterized in that the support pressure joining is carried out while forming internal threads in a plurality of straight cylindrical support pressure joining pilot holes 14 and 28 formed in advance on the deck plate 10 and the mounting flange 27, respectively.

  According to the present invention, the deck plate and the mounting flange need only be formed with a straight cylindrical (FIG. 10) bearing support joint hole, and it is necessary to form a female screw hole in the pilot hole. Since there is no, manufacturing work is simplified.

The present invention
The support hole joining pilot hole 14 of the deck plate 10 is formed through the deck plate 10 in the thickness direction,
The end of the tapping bolt 30 does not protrude from the upper surface of the deck plate 10.

  According to the present invention, the deck plate and the mounting flange are jointed by a tapping bolt, which is a one-side bolt constructed from one side, and the end of the tapping bolt does not protrude from the upper surface of the deck plate. Therefore, the end of the tapping bolt does not enter the pavement such as asphalt, the pavement layer thickness can be reduced, the pavement is not damaged, and the peeling and construction work for renewal repair of the pavement is not hindered. The pavement may be made of other materials as well as asphalt.

  The bearing support with plastic deformation or elastic deformation by the tapping bolt prevents the drainage of the road surface from leaking from the upper surface of the deck plate downward through the through hole. Even if the waterproof function of the waterproof layer 11 (FIG. 1) on the deck plate is impaired due to deterioration over time, water does not leak to the back side of the deck plate.

  Since the bearing holes for bearing support joints on the deck plate and bearing holes for bearing mounting on the mounting flange are both through-holes, there is no stress concentration at the bottom of the holes in the case of non-through holes, and the surface of the inner peripheral surface Work finishing and deburring are easy, and tapping bolt bearing joining can be achieved with high accuracy. This also improves durability. In another embodiment of the present invention, the support hole joining pilot hole of the deck plate may have a bottom without penetrating the deck plate in the thickness direction.

The present invention
A transverse rib 40 for stiffening the deck plate 10; the longitudinal rib 20 continues through the web 41 of the transverse rib 40 at the intersection of the longitudinal rib 20 and the transverse rib 40;
A connecting member 50 having an L-shaped cross section in which the first mounting piece 51 and the second mounting piece 52 are bent and connected,
The cross-position tapping bolt 55 that presses and joins the web 26 of the vertical rib 20 and the first mounting piece 51, and the web of the horizontal rib 40. 41, and a bolt 56 for joining the second mounting piece 52 to each other.

  According to the present invention, the crossing position tapping bolt is tightened from the first mounting piece of the connecting member having the L-shaped cross section to the vertical rib web at the crossing position of the vertical rib and the horizontal rib. Since the web and the first mounting piece are pressure-bonded and the web of the lateral rib and the second mounting piece are friction-bonded or pressure-bonded, the shearing force from the vertical rib is surely applied to the web of the horizontal rib via the connecting member. To the main girder that is a vertical girder. The crossing position tapping bolt achieves a bearing connection in the same manner as the tapping bolt that supports the deck plate and the mounting flange. Since the crossing position tapping bolt is a one-side bolt constructed from one side that can be bolted by tightening work from the outside of the vertical rib, the workability of manufacturing is good.

  The bolt for joining the web of the lateral rib and the second mounting piece may be configured to be frictionally joined by inserting the second mounting piece and the web of the lateral rib and screwing the nut. It may be a tapping bolt that is clamped and joined in a support pressure joining pilot hole formed in the piece and the web of the lateral rib. The connecting member may be provided on one side in the bridge axis direction with respect to the web of the lateral rib, but may be provided on the other side in the bridge axis direction.

  The longitudinal rib and the first mounting piece of the connecting member are supported and joined by a tapping bolt for crossing positions, and the lateral rib and the second attaching piece of the connecting member are supported and joined by a tapping bolt, or the bolt and the nut Friction welded by a combination of Therefore, the vertical rib and the horizontal rib are joined with high strength. Since there is no weld joint at the intersecting position of the vertical rib and the horizontal rib, the conventional weld toe is formed near the slit 44 (FIGS. 11 and 13) immediately below the vertical rib formed in the horizontal rib. The problem of fatigue cracks occurring in the longitudinal rib or transverse rib as a starting point is solved. Also from this viewpoint, a steel slab excellent in fatigue durability is realized.

  In prior art steel slabs, welded joints that join the deck plate and the upper end of the web of the closed cross-section vertical ribs, and welded joints at the intersections of the vertical and horizontal ribs, particularly generate and propagate fatigue cracks. It turns out to be easy. The present invention eliminates the problem of fatigue cracks in the weld metal at these two locations in the prior art, improves fatigue durability over a long period of time, eliminates the need for repairs, and facilitates inspection maintenance and maintenance management.

The present invention
It is a bridge equipped with the aforementioned steel deck.
The bridge of the present invention achieves the effect of the above-described steel deck.

The present invention
Prepare the aforementioned steel slab,
This is a structural type or structural form of a bridge characterized in that an upper structure including a steel deck as a bridge floor is supported by a lower structure through a support.

  According to the construction method of the present invention, the steel slab is paved on the deck plate to form a bridge floor, and constitutes the upper structure together with the floor set, main girder, main structure and the like. This upper structure is supported by the lower structure via a bearing. In this way, the bridge is constructed.

It is the cutting part end elevation seen from the cut surface perpendicular to a part of bridge axis which shows steel deck 1 of the bridge of one embodiment of the present invention. It is sectional drawing seen from the cut surface which follows the bridge axis which shows the steel deck. It is a top view which shows the vertical rib 20 of FIG. It is a bottom view which shows the vertical rib 20 of FIG. It is a figure which shows arrangement | positioning of FIG. 5 (1) and FIG. 5 (2). It is sectional drawing which looked at a part of bridge using the steel deck 1 from the cut surface perpendicular | vertical to a bridge axis. It is sectional drawing which looked at a part of bridge using the steel deck 1 from the cut surface perpendicular | vertical to a bridge axis. It is sectional drawing which simplifies and shows the steel deck 1 seen from the cut surface line VI-VI of FIG. 5 (1) and FIG. 5 (2). It is a figure which shows arrangement | positioning of Fig.7 (1)-FIG.7 (3). It is sectional drawing which looked at a part of bridge using the steel deck 1 from the cut surface perpendicular | vertical to a bridge axis. It is sectional drawing which looked at a part of bridge using the steel deck 1 from the cut surface perpendicular | vertical to a bridge axis. It is sectional drawing which looked at a part of bridge using the steel deck 1 from the cut surface perpendicular | vertical to a bridge axis. It is a figure which shows arrangement | positioning of Fig.8 (1)-FIG.8 (3). It is sectional drawing which shows the stringer 3 which looked at a part of bridge using the steel deck 1 from the cut surface which follows a bridge axis. It is sectional drawing which shows the stringer 3 which looked at a part of bridge using the steel deck 1 from the cut surface which follows a bridge axis. It is sectional drawing which shows the stringer 3 which looked at a part of bridge using the steel deck 1 from the cut surface which follows a bridge axis. It is an expanded sectional view which shows the structure which the tapping bolt 30 bears and joins the deck plate 10 and the attachment flange 27 in the state in which the steel deck 1 is used for the bridge. It is sectional drawing for demonstrating the operation | work which drills in the deck plate 10 with the attitude | position in which the up-down direction is reverse to the use condition as a bridge deck at the time of manufacture of the steel deck 1 in a factory. FIG. 6 is an enlarged sectional view showing a section XI in FIG. 5. 4 is a perspective view showing a connecting member 50. FIG. It is sectional drawing which expands and shows the section XIII of FIG. It is sectional drawing which expands and shows the section XIV of FIG. It is sectional drawing seen from the cut surface line XV-XV of FIG. It is sectional drawing seen from the cut surface line XVI-XVI of FIG. It is sectional drawing seen from the cut surface line XVII-XVII of FIG. It is sectional drawing for demonstrating operation | movement of the operation | work which closes the handhole 62 with the cover member 72, and makes it the state of FIG. It is sectional drawing which expands and shows the section XIX of FIG. It is a figure which shows arrangement | positioning of FIG. 20 (1) and FIG. 20 (2). It is sectional drawing corresponding to above-mentioned FIG. 5 (1) which looked at a part of bridge using the steel deck 1 in the other embodiment of this invention from the cut surface perpendicular | vertical to a bridge axis. It is sectional drawing corresponding to above-mentioned FIG. 5 (2) which looked at a part of bridge using the steel deck 1 in the other form of implementation of this invention from the cut surface perpendicular | vertical to a bridge axis. It is sectional drawing which expands and shows the section XXI of FIG. 20, and respond | corresponds to above-mentioned FIG. The structure in which the deck plate 10 and the mounting flange 27 of the vertical rib 20 are jointly supported by the tap bolts 130 in the steel floor slab 1 according to still another embodiment of the present invention is used for the steel floor slab 1 as a bridge. It is an expanded sectional view shown in the state where it is done. When the steel floor slab 1 is manufactured in the factory, a straight cylindrical pilot hole 128 formed in advance on the mounting flange 27 of the vertical rib 20 in a posture that is upside down from the state of use as a bridge floor in FIG. 6 is a cross-sectional view showing a state in which the cutting tool 17 of the drill tool 16 is guided and the right cylindrical cylindrical hole 114 is drilled in the deck plate 10. 22 is a cross-sectional view showing a state in which the female screw holes 129 and 115 are formed in the pilot holes 128 and 114 in FIG. 22 (2) upside down in FIG. It is the state at the time of manufacture of the factory. It is a perspective view which shows the state which gave the marking for looseness confirmation of the bolt head 31 of the tapping bolt 30. FIG. It is sectional drawing which each shows the closed cross-section vertical rib 20a-20c in each other form of implementation of this invention.

  FIG. 1 is an end view of a cut portion of a bridge steel floor slab 1 according to an embodiment of the present invention as viewed from a cut surface perpendicular to a part of the bridge axis. The steel deck 1 includes a deck plate 10, a closed cross-section vertical rib 20 that stiffens the deck plate 10, a tapping bolt 30, and a lateral rib 40 that stiffens the deck plate 10 (FIGS. 5 and 6 described later). It is comprised including.

  2 is a cross-sectional view of the steel slab 1 as seen from a cut surface along the bridge axis, FIG. 3 is a plan view showing the vertical rib 20 of FIG. 2, and FIG. 4 shows the vertical rib 20 of FIG. It is a bottom view. 1 to 4 show the vertical ribs 20 at the same scale with respect to the longitudinal rib span length L, which is the distance between the centers of the single horizontal ribs, and the omitted portion of FIGS. 2 to 4 is 24 cm in the drawing. The longitudinal ribs 20 are configured symmetrically with respect to a symmetry plane 21 perpendicular to the paper surface of FIG. 1, and together with the lower surface of the deck plate 10, the bridge axis direction (direction perpendicular to the paper surface of FIG. 1, left-right direction of FIG. 2, FIG. A vertical rib main body 23 forming a closed space 22 extending in the vertical direction in FIG. 4 and an upper end portion 24 of the vertical rib main body 23 are connected to each other in a direction perpendicular to the bridge axis (the horizontal direction in FIG. 1 and the plane of FIG. 2). And a flat mounting flange 27 disposed on the bottom surface of the deck plate 10. The vertical rib main body 23 has a flat plate-like lower flange 25 and flat plate-like webs 26 rising up on both sides of the lower flange 25, each having a rounded arc shape facing the closed space 22 and having a concave curvature. It is a U trough shape that is continuous through parts and has an overall trapezoidal cross-sectional shape. The mounting flange 27 is connected to the vertical rib main body 23, and thus to the upper end 24 of each web 26, with a rounded arc shape, facing the closed space 22 and the deck plate 10 via a convex bent portion. It is formed outward in the direction perpendicular to the axis. In the plan view of FIG. 3, on the inner peripheral surface of the vertical rib 20, the concave bent portion is connected to the lower flange 25 and the web 26 and extends in the bridge axis direction, and the convex bent portion is attached to the web 26. A tangent line extending in the direction of the bridge axis and connected to the flange 27 is indicated by a solid line. In the bottom view of FIG. 4, on the outer peripheral surface of the vertical rib 20, the concave bent portion extends in the bridge axis direction where the concave bent portion is connected to the lower flange 25 and the web 26, and the convex bent portion is the web 26 and the mounting flange. And a tangent line extending in the direction of the bridge axis and connected to each other is indicated by a solid line.

  The vertical ribs 20 can be easily manufactured in one process by cold pressing or roll forming a structural steel plate, for example. An asphalt pavement 13 is constructed on the deck plate 10. This asphalt pavement 13 is composed of a very thin adhesive layer (not shown), a waterproof layer 11 made of goose asphalt, etc. and a pavement main body upper layer 12 made of modified asphalt, etc., formed in this order from the bottom to the top. The

  A plurality of tapping bolts 30 are arranged at equal intervals in the bridge axis direction, and are advanced by being fastened to the deck plate 10 from the mounting flange 27, and fix the deck plate 10 and the mounting flange 27 by bearing joining.

  FIG. 5 is a cross-sectional view of a part of a bridge using the steel deck 1 as seen from a cut surface perpendicular to the bridge axis, and FIG. 6 is a cross-sectional line VI- of FIG. 5 (1) and FIG. FIG. 7 is a simplified cross-sectional view showing the steel slab 1 viewed from VI, and FIG. 7 is a cross-sectional view of a part of the bridge using the steel slab 1 as seen from a cut surface perpendicular to the bridge axis. To simplify the drawing, bolts and nuts viewed from the front may be drawn with circles or dots, and combinations of bolts and nuts viewed from the side may be drawn with line segments, and bolts, nuts, and other parts may be shown. May be omitted. The scale of each figure may be different.

  On the lower surface of the deck plate 10, a plurality of (for example, six) vertical ribs 20 extending in the bridge axis direction (the direction perpendicular to the paper surface of FIG. 5 and the left-right direction in FIG. 6) have a vertical rib center equal to the bridge axis perpendicular direction. It is fixed by the tapping bolt 30 as described above with a gap C (FIG. 5). A plurality of (for example, seven) lateral ribs 40 extending in the direction perpendicular to the bridge axis are arranged on the lower surface of the deck plate 10 at intervals in the bridge axis direction, and the upper ends of the lateral ribs 40 are welded. The vertical rib 20 continues through the web 41 of the horizontal rib 40 at the intersection of the vertical rib 20 and the horizontal rib 40, and is connected by a connecting member 50 (FIG. 11). The vertical ribs 20 adjacent in the bridge axis direction are connected by the vertical rib joint 60. The lateral ribs 40 adjacent in the direction perpendicular to the bridge axis are connected by a lateral rib joint 80.

  FIG. 8 is a cross-sectional view showing a stringer 3 in which a part of a bridge using the steel deck 1 is viewed from a cut surface along the bridge axis. The horizontal rib 40 of the steel deck 1 is supported by a vertical girder 3 of an I girder (plate girder) type as a main girder. The stringers 3 adjacent to each other in the bridge axis direction are connected by a stringer joint 90. A vertical stiffener 8 is provided on the web of the stringer 3. The assembly of the upper structure 5 configured by including the steel deck 1 as a bridge floor is supported by the lower structure 7 including the abutment and the pier via the support 6.

  FIG. 9 is an enlarged cross-sectional view showing a configuration in which the tapping bolt 30 is pressure-bonded to the deck plate 10 and the mounting flange 27 in a state where the steel deck 1 is used for a bridge. In the factory, the steel floor slab 1 is manufactured with the tapping bolt 30 screwed from the mounting flange 27 to the deck plate 10 with the top and bottom of FIG. 9 turned upside down. The tapping bolt 30 has a hexagonal bolt head 31, a washer portion 32, and a shaft portion 33 that are integrally formed. The outer surface of the tapping bolt 30 is surface-treated with a higher hardness than the steel material of the deck plate 10 and the mounting flange 27. The The shaft portion 33 is engraved with a male thread 34 over the entire length of the neck length L33. Accordingly, the shaft portion 33 is used for bearing support joining of the mounting flange 27 that is not subjected to female thread processing by rotating the bolt head 31 while applying a pressing force toward the mounting flange 27 and the deck plate 10. Advancing while forming a female screw into the pilot hole 28 and the pilot hole 14 for supporting pressure joining of the deck plate 10 that has not been subjected to female threading, the female screw is formed by plastic deformation to perform the supporting pressure joining. Achieve. The clearance between the mounting flange 27 and the deck plate 10 is substantially zero. The tapping bolt 30 is on a common straight line with the axis of each supporting joint 14 and 28 having the same inner diameter as a pair. Therefore, when the tapping bolt 30 is tightened, the tapping bolt 30 is arranged. It is possible to prevent undesired stresses due to bending moments and the like.

According to the tapping bolt 30, the plastic deformation of the female screw does not produce cutting waste.
An end portion 35 of the shaft portion 33 of the tapping bolt 30 opposite to the bolt head 31 (upper side in FIG. 9) does not protrude from the upper surface of the deck plate 10, that is, substantially flush with the upper surface of the deck plate 10. For example, only the order of 10 ⁻¹ mm for the production accuracy of the length L33 under the neck of the tapping bolt 30 is uneven from the top surface of the deck plate. The end portion 35 of the tapping bolt 30 may be recessed from the upper surface of the deck plate 10. Therefore, since the end portion 35 of the bolt 30 does not enter the asphalt pavement 13, the layer thickness of the pavement 13 may remain small and the pavement 13 will not be damaged. Since the end portion 35 of the bolt 30 does not protrude from the upper surface of the deck plate 10, it does not hinder peeling and construction work for renewal repair of the pavement 13.

  When the thickness of the vertical rib 20 including the mounting flange 27 is t20, the axial length (= L33−t20) of the shaft portion 33 into which the shaft portion 33 of the tapping bolt 30 is screwed into the deck plate 10 is a bearing pressure. A value that can achieve the bonding strength is selected. According to the bearing support of the present invention, the thickness of the steel material of the deck plate 10 is thin, so that the shaft length of the shaft portion 33 into which the tapping bolt 30 is screwed is relatively short, and the friction bonding between the deck plate 10 and the mounting flange 27 is performed. Even if the high axial force required for the operation cannot be exhibited or there is no axial force, the bearing support can be reliably achieved.

  FIG. 10 is a cross-sectional view for explaining an operation of drilling holes in the deck plate 10 in a posture in which the vertical direction is opposite to the usage state as a bridge floor when the steel deck 1 is manufactured in a factory. The steel floor slab 1 is manufactured by being assembled in the posture of FIG. 10 in which the vertical direction is reversed with respect to FIGS. 2, 5, 9, and the like showing use in a bridge. A plurality of (for example, 21 as described above) support bearing joining pilot holes 28 are formed in advance in rows in the mounting flange 27 at equal intervals in the bridge axis direction. The deck plate 10 is horizontally installed on a surface plate or a processing table 15. The vertical rib 20 is mounted on a predetermined position on the deck plate 10 to be subjected to bearing support, and the deck plate 10 and the vertical rib 20 are temporarily fixed by a fixing jig so as not to be displaced. For example, the fixing jig may be configured to magnetically attract the deck plate 10 and the vertical rib 20 to each other in the proximity direction using the magnetic force of the magnet, and press the deck plate 10 and the vertical rib 20 in the proximity direction to each other. A configuration in which force is applied and pinched may be used, or another configuration may be used.

  The cutting tool 17 of the drill tool 16 is guided by the support pressure joining pilot hole 28 previously drilled in the mounting flange 27 of the vertical rib 20 temporarily fixed on the deck plate 10, and directly below the mounting flange 27. The bearing support joint holes 14 paired with the bearing support joint holes 28 of the mounting flange 27 are sequentially drilled in the deck plate 10 in the bridge axis direction.

  10, the mounting flange 27 of the vertical rib 20 is pressure-bonded to the upper surface of the deck plate 10, and the horizontal rib 40 is fixed to complete the steel deck 1. A stringer 3 is attached to the steel deck 1 to obtain an assembly of the superstructure 5. This assembly is transported from the bridge factory to the construction site, and the bridge is erected from the state shown in FIG.

  An example of specific dimensions will be described. The present invention should not be construed as limited to these dimensions. In FIG. 1 and FIG. 2, the distance A of the entire width between both side ends of the pair of mounting flanges 27 is 482 mm, the width B of the lower flange 25 is 144 mm, and the upper surface of the mounting flange 27 and the lower surface of the lower flange 25 are The height H between them is 240 mm, and the single span length L (FIG. 2) of the vertical rib 20 shown in FIGS. 2 to 4 is 2 m. In the single block steel deck 1 of FIGS. 5 to 7, the length La (FIG. 6, FIG. 7) of the deck plate 10 in the bridge axis direction is 14 m, and the width D (FIG. 5, FIG. 5) FIG. 6) is 3.6 m. Each vertical rib 20 fixed to the deck plate 10 extends to the length La of the deck plate 10. The number of the lateral ribs 40 is 7 (= 14/2) because the longitudinal rib span length L is 2 m as described above. The distance C between the centers adjacent to each other in the direction perpendicular to the bridge axis (FIGS. 5 and 13) is 600 mm.

  The thickness t20 (FIG. 9) of the vertical rib 20 is 6 mm (may be 8 mm), and the thickness t10 (FIG. 9) of the deck plate 10 may be 12 mm (14 mm or more, for example, 16 mm). ).

  The bolt pitch in the bridge axis direction of the bearing hole 28 for supporting pressure joining, and therefore the tapping bolt 30 is standard at an interval of 65 mm. Therefore, the tapping bolt 30 is screwed at 15 pieces / m. In the length L, there are thirty support pressure joining pilot holes 28 for the tapping bolt 30.

  The outer diameter D34 (FIG. 10) of the external thread 34 of the tapping bolt 30 is φ16 mm. The inner diameters D14 and D28 of the support pressure bonding pilot holes 14 and 28 are both φ15.5 mm (D14 = D28, D14 <D34, D28 <D34). The length L33 below the neck of the tapping bolt 30 (FIG. 9) is, for example, 18 mm (= 6 + 12), and is selected to be equal to or less than the sum of the thickness t20 of the vertical rib 20 and the thickness t10 of the deck plate 10 (t20 <L33 ≦ (T20 + t10)).

  In another embodiment of the present invention, the support pressure joining pilot hole 14 of the deck plate 10 and the support pressure joining pilot hole 28 of the mounting flange 27 may be drilled by other methods. The bearing pressure joining pilot holes 14 and 28 forming a pair may have different inner diameters for each pair, and may not be arranged in a row in the bridge axis direction.

  FIG. 11 is an enlarged cross-sectional view of the section XI in FIG. The vertical rib 20 continues through the web 41 of the horizontal rib 40 at a position where the vertical rib 20 intersects the horizontal rib 40. The vertical rib 20 and the horizontal rib 40 are connected by a connecting member 50 at their intersecting position.

  In the joining of the longitudinal rib web 26 and the transverse rib web 41 by conventional welding, many occurrences of fatigue cracks starting from the toe of the welded portion have been confirmed. In the present invention, by eliminating the joining by welding and using the bolt joint, the cause of the occurrence of fatigue cracks can be fundamentally eliminated, and a structure without fear of the occurrence of fatigue cracks can be realized. That is, since welding is not used here, it is possible to fundamentally prevent the occurrence of fatigue cracks from the welded portion, which frequently occurs in conventional welding structures.

  FIG. 12 is a perspective view showing the connecting member 50. The connecting member 50 includes first and second attachment pieces 51 and 52 and is made of an angle member having an L-shaped cross section. The first mounting piece 51 is formed with a plurality of (for example, two) support pressure bonding pilot holes 53. A plurality of (for example, two) bolt insertion holes 54 are formed in the second mounting piece 52. The tapping bolts 55 for crossing positions are tightened from the bearing holes 53 for supporting joints of the first mounting pieces 51 to the bearing holes for supporting joints formed in the webs 26 of the longitudinal ribs 20, and the first mounting pieces 51 and the webs. 26 is pressure-bonded. The bolt 56 is inserted through the bolt insertion hole 54 of each second attachment piece 52 and the bolt insertion hole formed in the web 41 of the lateral rib 40, and the nut is screwed to connect the second attachment piece 52 and the web 41. Friction welding. The support joint of the crossing position tapping bolt 55 is the same as the support joint by the tapping bolt 30 that supports the deck plate 10 and the mounting flange 27. Since the crossing position tapping bolt 55 can be bolted by a tightening operation from the outside of the vertical rib 20, the workability of manufacturing is good.

  Instead of the crossing position tapping bolt 55, a so-called hack-type one-side bolt (hereinafter abbreviated as a hack-type bolt), which is a one-side bolt for friction joining, may be used. A hack-type bolt forms a bolt head on the side opposite to the tightening side by, for example, a rotational torque of a nut or a bolt shaft portion, and then a small-diameter fracture portion of the bolt shaft portion shears when a predetermined axial force is achieved. It has a configuration.

  That is, the hack bolt is basically a pin that is a bolt shaft portion having a shaft portion and a large-diameter head portion formed at an end portion of the shaft portion, and the shaft portion is on the tightening side from the head portion. It includes a bulging deformation sleeve that is sequentially inserted toward the free end, a compression force transmitting sleeve, a shear washer, and a support washer, and further includes a nut. The shaft portion has a first male screw portion, a small-diameter groove-like break portion, and a second male screw portion sequentially from the head toward the free end portion in the middle of the axial distance from the head portion. And a 3rd external thread part is formed. The nut can be screwed from the third male screw portion to the second and third male screw portions. The bulging deformation sleeve has a lower strength than the compressive force transmitting sleeve, and bulges and deforms outward in the radial direction by the compressive force inward in the axial direction. The shear washer has its inner peripheral part in contact with the end face on the free end side of the shaft part of the compression force transmitting sleeve, and its outer peripheral part is received by and supported by the support washer and therefore by the nut. The shear wrench tool includes a first rotation driving unit that rotates the nut and a second rotation driving unit that is screwed into the third male screw unit to be rotated.

  The nut is rotationally driven relative to the pin by the first and second rotational drive portions of the shear wrench tool. As a result, the bulging deformation sleeve is compressed inward in the axial direction between the head, the compression force transmitting sleeve and the shear washer, and in the closed space 22 of the vertical rib 20 on the side opposite to the tightening side. , A bulging deformation head which is a bolt head is formed. The outer diameter of the bulging deformation head is larger than the inner diameter of the bolt insertion hole of the web 26. When the nut 95 is further rotated, the shear washer is sheared in the thickness direction by the compression force transmitting sleeve. In this state, the web 26 and the first attachment piece 51 are brought into contact with each other by the axial force of the pin corresponding to shearing of the shear washer between the bulging deformation head and the nut via the supporting washer, and the friction is caused. Be joined. After the shear washer is sheared, when the nut is further rotated, introduction of the axial force of the pin starts. The state in which the axial force of the hack-type bolt during the shear failure of the shear washer is exhibited is called primary tightening.

  In order to achieve the final tightening of the hack-type bolt, after the primary tightening, the third male thread portion is rotationally driven in a state where the rotation of the nut is prevented, and the first mounting piece 51 and the web 26 of the vertical rib 20 are In addition, a larger axial force of the pin is introduced. When a predetermined axial force of the pin is introduced, the fracture portion is twisted outwardly in the axial direction by the nut and sheared, thereby achieving final tightening. Thus, the frictional joining of the web 26 and the first mounting piece 51 by the final fastening of the hack bolt is completed. After the final tightening, the first rolling drive portion is removed from the nut, and the sheared third male screw portion is removed from the second rotational drive portion.

  The connecting member 50 may be provided on one side in the bridge axis direction with respect to the web 41 of the lateral rib 40, but may also be provided on the other side in the bridge axis direction.

  The upper end portion 42 of the web 41 of the horizontal rib 40 is fixed to the lower surface of the deck plate 10 by fillet welding. The load from the vertical rib 20 is reliably transmitted to the horizontal rib 40 and can be supported by the support beam of the vertical beam 3 or the like. The web 41 is provided with a scallop 43 near the attachment flange 27 and a slit 44 near the lower flange.

  In another embodiment of the present invention, the second mounting piece 52 is replaced with a configuration in which a nut is screwed into a bolt 56 that passes through the second mounting piece 52 and the web 41 of the lateral rib 40 to achieve friction joining. Further, it may be a support bearing by a tapping bolt that is tightened to the web 41 of the lateral rib 40.

  FIG. 13 is an enlarged cross-sectional view of section XIII in FIG. FIG. 13 shows a lateral rib joint 80 that joins the lateral ribs 40 of the steel deck 1 adjacent in the direction perpendicular to the bridge axis (the lateral direction in FIG. 13). The deck plates 10 of the steel deck 1 adjacent in the direction perpendicular to the bridge axis are brought into contact with each other and welded. Each free end of the web 41 of the lateral rib 40 has a scallop 81 facing the adjacent deck plate 10.

  Contact members 83 and 84 are brought into contact with the free end portions of the web 41 of the lateral rib 40, respectively. The nuts are screwed into the bolts 85 and 86 through which the contact members 83 and 84 and the web 41 of the lateral rib 40 are inserted to be frictionally joined, and the lateral rib 40 is connected in the direction perpendicular to the bridge axis. In the horizontal rib joint 80, the vertical ribs 20 adjacent to each other in the direction perpendicular to the bridge axis of each steel deck 1 in FIG. 13 are also arranged with the same value as the longitudinal rib center distance C described above with reference to FIG. The The attachment member 83 is selected to have a width smaller than the attachment member 84 in accordance with the distance between the connecting members 50 adjacent to each other in the direction perpendicular to the bridge axis, and depending on the size of the attachment members 83, 84, the bolt The number of 85 and 86 is determined.

  The contact members 83 and 84 are also provided on one side of the web 41 (the surface facing the upper side of FIG. 13) and the other side (the surface facing the lower side of FIG. 13). Fixed by nut. In another embodiment of the present invention, instead of frictional joining using bolts 85 and 86 and nuts, tapping bolts tightened in bearing support joining pilot holes formed in the contact members 83 and 84 and the web 41 are used. It may be a bearing joint.

  14 is an enlarged cross-sectional view of section XIV in FIG. 7, FIG. 15 is a cross-sectional view taken along section line XV-XV in FIG. 14, and FIG. 16 is a section line XVI-XVI in FIG. FIG. 17 is a cross-sectional view taken along the section line XVII-XVII in FIG. 16. Referring to these drawings, FIG. 14 shows a longitudinal rib joint 60 that joins the longitudinal ribs 20 of the steel deck 1 adjacent in the bridge axis direction (left-right direction in FIG. 14). The deck plates 10 of the steel deck 1 adjacent in the bridge axis direction are brought into contact with each other and welded. Each free end of the web 26 of the longitudinal rib 20 forms a scallop 68 that faces the adjacent deck plate 10. Each free end of the lower flange 25 of the vertical rib 20 is formed with a pair of notches 37 that open in the direction of the bridge axis and face each other to form a pair. A hand hole 62 is formed for a person to insert an arm or the like to configure the vertical rib joint 60. Each free end portion of the web 26 of the vertical rib 20 is brought into contact with the contact members 63 and 64 in the outer side and in the closed space 22, and is joined by a high-strength bolt 65 and a nut 66. 20 is connected in the direction of the bridge axis.

  The hand hole 62 is closed by a lid member 72 so as to be freely opened and closed. The lid member 72 has a rectangular lid plate 73 that covers the hand hole 62 on the inner lower flange 25 of the vertical rib 20. At the four corners of the both ends of the bridge plate 73 in the bridge axis direction (left and right directions in FIGS. 16 and 17), locking notches 74 opened outward in the bridge axis direction are formed. The shaft portion of the bolt 76 is gently inserted into the bolt insertion hole 75 formed in the lower flange 25 corresponding to the locking notch 74, and the bolt head is the locking notch 74 and the bolt insertion hole 75. Is selected so as to be locked to the upper surface of the lid plate 73 and the lower flange 25 inside the vertical rib 20 without being inserted. The shaft portion of the bolt 76 is capable of inserting and removing the locking notch 74 outward in the bridge axis direction of the lid plate 73. The U-shaped handle 79 is fixed to the lower part of the cover plate 73, and makes it easy for an operator to handle the cover plate 73 from the outside of the hand hole 62.

  With the handhole 62 open, the attachment member 64 and the bolt 65 are brought inward of the longitudinal rib 20, and the web 26 adjacent in the bridge axis direction is connected together with the attachment member 63 and the nut 66. Thereafter, the hand hole 62 is closed by the lid member 72.

  FIG. 18 is a cross-sectional view for explaining the operation of the operation of closing the handhole 62 with the lid member 72 to bring it into the state of FIG. First, as shown in FIG. 18A, the shaft portion of the bolt 76 is inserted into the bolt insertion hole 75 inside the vertical rib 20, and the bolt head is locked to the upper surface of the lower flange 25. Next, as shown in FIG. 18 (2), the lid plate 73 is carried into the vertical rib 20 through the hand hole 62, and the shaft portion protruding below the bolt 76 from the outside of the vertical rib 20 is placed on the operator. The shaft portion of the bolt 76 is inserted between the bolt head of the bolt 76 and the upper surface of the lower flange 25 into the locking notch 74 of the lid plate 73 while being pushed up by the finger 77 of the hand. Thereafter, the finger 77 is released from the shaft portion of the bolt 76, and the nut 78 is screwed into the shaft portion protruding downward. In this way, the cover plate 73 is fixed to the lower flange 25 and the hand hole 62 is closed by the cover member 72 as shown in FIG.

  A partition for partitioning the closed space 22 from the atmosphere in order to prevent rust and corrosion, inward of the scallop 68, the hand hole 62, and the bolt insertion hole 75 in the vicinity of both free ends of the vertical rib 20. The plate 38 is welded and fixed across the inner peripheral surface of the vertical rib 20 and the lower surface of the deck plate 10. After the deck plate 10 and the mounting flange 27 of the longitudinal rib 20 are fixed by bearing support as described above, a seal material is applied from the outside to the contact portion between the deck plate 10 and the mounting flange 27 so that a gap is formed. The airtightness of the closed space 22 is ensured, and the outer surface is rust-prevented with a synthetic resin compounding paint or the like.

  FIG. 19 is an enlarged sectional view showing a section XIX in FIG. The stringers 3 that support the steel deck 1 and are adjacent to each other in the bridge axis direction (left and right direction in FIG. 19) are connected by a stringer joint 90.

The stringer 3 includes a web 91, a deck plate 10 as an upper flange thereof, and a lower flange 93. Each free end portion of the deck plate 10 as an upper flange adjacent in the bridge axis direction is welded and joined, and each free end portion of the web 91 forms a scallop 94 facing the deck plate 10 as an adjacent upper flange.
A contact member 95 is brought into contact with each free end portion of the adjacent web 91. A bolt 96 is inserted into the web 91, an attachment member 95 that abuts against one surface of the web 91, and another attachment member that abuts against the other surface of the web 91, and a nut is screwed into the bolt 96. Friction welding is performed. Two lower and upper attachment members 97 and 98 are attached to and joined to the lower flange 93.

  FIG. 20 is a cross-sectional view of a part of a bridge using the steel deck 1 according to another embodiment of the present invention as viewed from a cut surface perpendicular to the bridge axis, and corresponds to FIG. 5 described above. This embodiment is similar to the above-described embodiment, and corresponding portions are denoted by the same reference office or by adding a subscript a. It should be noted that at the crossing position where the vertical ribs 20 pass through the web 41 of the horizontal ribs 40, instead of joining by the L-shaped connecting member 50 in the above-described embodiment, the web 26 of the vertical ribs 20 and The web 41 of the lateral rib 40 is fillet welded at reference portions 45 and 46 in FIG.

  FIG. 21 is an enlarged cross-sectional view of the section XXI in FIG. 20 and corresponds to FIG. 13 described above. The transverse rib joint 80a joins the transverse ribs 40 of the steel slab 1 adjacent to each other in the direction perpendicular to the bridge axis (left and right direction in FIG. 21). An abutting member 84 a is in contact with each free end portion of the web 41 of the lateral rib 40. A nut is screwed into a bolt 86a that passes through the contact member 84a and the web 41 of the lateral rib 40 to be frictionally joined, and the lateral rib 40 is connected in a direction perpendicular to the bridge axis. In order to obtain the above-described distance C between the longitudinal rib centers in FIG. 21, the longitudinal portion 20 is formed to be smaller as the width of the upper portion 89 of the attachment member 84 a becomes higher. The remaining configuration in the embodiment of FIGS. 20 and 21 is substantially the same as that of the embodiment of FIGS.

  FIG. 22 is a sectional view showing still another embodiment of the present invention. In this embodiment, in place of the tapping bolts 30 and 55 that advance while threading themselves, the tap bolts 130 that are support joints that are screwed into the female screw holes 129 and 115 in which the female screws are erected are provided. Is used to achieve pressure bearing joining between the deck plate 10 and the mounting flange 27 of the longitudinal rib 20. FIG. 22 (1) shows a structure in which the deck plate 10 and the mounting flange 27 of the longitudinal rib 20 are pressure-bonded by the tap bolts 130 in the steel floor slab 1, and the steel floor slab 1 is used for a bridge. It is an expanded sectional view shown in a state. In the tap bolt 130, a hexagonal bolt head 131, a washer portion 132, and a shaft portion 133 are integrally formed. The shaft 133 is engraved with a male thread over the entire length of the neck length. The support joint by the tap bolt 130 shown in FIG. 22 (1) is performed in the order of the operations shown in FIGS. 22 (2) and 22 (3). At the factory, the steel floor slab 1 has tapped bolts 130 extending from the mounting flange 27 to the deck plate 10 in the state shown in FIGS. 22 (2) and 22 (3) with the top and bottom of FIG. The steel floor slab 1 is manufactured by being screwed. Manufacture work in such a factory can be performed by so-called downward construction, so that workability is good.

  FIG. 22 (2) shows that straight cylindrical pilot holes 114, 128 are drilled in the deck plate 10 and the mounting flange 27 of the vertical rib 20 in order to form the female screw holes 129, 115 for the tap bolt 130. It is sectional drawing which shows the state made. The cutting tool 17 of the drill tool 16 is guided by the prepared hole 128 formed in the mounting flange 27 of the vertical rib 20 in advance, and the prepared hole 114 is drilled in the deck plate 10.

  FIG. 22 (3) is a cross-sectional view showing a state in which internal threads are formed using taps in the pilot holes 128 and 114 to form internal thread holes 129 and 115, respectively. Since it is engraved in the pilot holes 128 and 114, the tap bolt 130 is screwed together in common with the screw holes 129 and 115, and the deck plate 10 and the mounting flange 27 of the vertical rib 20 are supported and joined. The female screw holes 129 and 115 are formed so as to be screw-joined when the tap bolt 130 is directly screwed.

  For example, the inner diameters D128 and D114 of the pilot holes 128 and 114 are both φ14.0 mm, and the outer diameter D130 of the tap bolt 130 is φ16 mm.

  In another embodiment of the present invention, a female screw hole 129 may be formed in advance in place of the straight cylindrical pilot hole 128 formed in advance in the mounting flange 27 of the vertical rib 20 in FIG. Good.

  In another embodiment of the present invention, instead of the tapping bolts 30 and 55 and the tap bolt 130, the screw is advanced while being threaded by itself, and the female screw is formed by plastic deformation or by cutting and is screw-joined. Or a screw may be sufficient, and also what is called a thread forming screw, a tapping screw, a tap bolt, etc. may be sufficient.

  FIG. 23 is a perspective view showing a state where the bolt head 31 of the tapping bolt 30 is marked for looseness confirmation. A coating 36 is applied linearly from the bolt head 31 to the mounting flange 27 of the vertical rib 20 for marking. Thereby, it is possible to easily visually check whether or not the tapping bolt 30 has been loosened after being tightened. Similar markings are also performed in relation to the cross position tapping bolt 55, the tapping bolt 130, the bolt 56, and the nut 66, and the like. In a configuration in which a coating such as a rust preventive coating or a synthetic resin blend coating is applied over the bolt head 31, the vertical rib 20, and the bottom surface of the deck plate 10 to prevent corrosion, whether or not the tapping bolt 30 is loose is determined by the coating. The cracks can be inspected by visually checking, and the same applies to the bolts 55, 130 and the like.

  FIG. 24 is a cross-sectional view showing closed cross-section vertical ribs 20a to 20c in other embodiments of the present invention. These vertical ribs 20a to 20c may be used instead of the vertical ribs 20 described above. FIG. 24 (1) shows a cross section of the round closed cross-section rib 20a. The vertical ribs 20a for stiffening the deck plate 10 are connected to the vertical rib main body 23a that forms a closed space extending in the bridge axis direction together with the lower surface of the deck plate 10 and the upper end of the vertical rib main body 23a in the direction perpendicular to the bridge axis. And an attachment flange 27a formed outward. The vertical rib main body 23a has an arcuate lower flange 25a that protrudes downward, and a web 26a that rises in series with both sides of the lower flange 25a.

  24 (2) shows a cross section of the V-shaped closed cross-section rib 20b, and FIG. 24 (3) shows a cross section of the Y-shaped closed cross-section rib 20c. The vertical rib main bodies 23b and 23c of the vertical rib main bodies 23b and 23c are formed of a web that forms a flat plate pair and do not have a lower flange. Each of these webs is connected with mounting flanges 27b and 23c outwardly. Other configurations in each embodiment of FIG. 23 are the same as those in the above-described embodiment. Such and other configurations are also within the spirit of the invention.

  The steel decks of the present invention can be used to realize plate girders, girder bridges such as box girders, truss bridges, suspension bridges and a wide variety of other structural bridge types.

DESCRIPTION OF SYMBOLS 1 Steel floor slab 3 Vertical girder 10 Deck plate 13 Asphalt pavement 14, 28, 53, 114, 128 Pilot hole for bearing support 20 Vertical rib 22 Closed space 23, 23a-23c Vertical rib main body 25, 25a Lower flange 26, 26a, 41 Web 27, 27a to 27c Mounting flange 30 Tapping bolt 40 Horizontal rib 50 Connecting member 51 First mounting piece 52 Second mounting piece 55 Tapping bolt for crossing position 60 Vertical rib joint 80, 80a Horizontal rib joint 90 Vertical girder joint 130 Tap bolt

Claims (8)

(A) Deck plate,
(B) a closed cross-section vertical rib that stiffens the deck plate,
A vertical rib body that forms a closed space that extends in the bridge axis direction along with the lower surface of the deck plate, and an attachment that is formed outwardly in the direction perpendicular to the bridge axis and connected to the upper end of the vertical rib body, and disposed on the lower surface of the deck plate A closed cross-section longitudinal rib having a flange, and (c) a tapping bolt that is spaced apart in the direction of the bridge axis, is advanced from the mounting flange to the deck plate, and supports the deck plate and the mounting flange in a bearing manner. Steel floor slab characterized by. The vertical rib body of the closed cross-section vertical rib is:
Has a lower flange and a web that rises on both sides of the lower flange,
The steel slab according to claim 1, wherein the mounting flange is formed outwardly in a direction perpendicular to the bridge axis so as to be connected to an upper end portion of each web. The tapping bolt is
3. The support pressure joining is carried out while a female screw is being formed by itself in a plurality of straight cylindrical support pressure joining pilot holes formed in advance on the deck plate and the mounting flange, respectively. Steel floor plate. The deck plate joint for pressure bearing joining is formed through the deck plate in the thickness direction,
The end part of a tapping bolt does not protrude on the upper surface of a deck plate, The steel floor slab described in any one of Claims 1-3 characterized by the above-mentioned. It has a horizontal rib that stiffens the deck plate, and at the intersection of the vertical rib and the horizontal rib, the vertical rib continues through the web of the horizontal rib,
A connecting member having an L-shaped cross section in which the first mounting piece and the second mounting piece are bent and connected;
Tightening bolt for cross position that presses and joins the web of the vertical rib and the first mounting piece, and the web of the lateral rib and the second mounting piece are joined. The steel slab according to claim 1, further comprising:   A steel bridge provided with a steel slab described in one of claims 1-5. A closed section vertical rib that stiffens the deck plate,
Lower flange,
A web that rises continuously on both sides of the lower flange, and has a mounting flange that is formed outwardly and continues to the upper end of each web, and is disposed on the lower surface of the deck plate.
The lower flange and web form a closed space with the bottom surface of the deck plate,
A closed section longitudinal rib characterized in that the deck plate and the mounting flange are bolted together. Preparing a steel deck according to one of claims 1 to 5,
A bridge construction method characterized in that an upper structure having a steel deck as a bridge floor is supported by a lower structure through a support.

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