JP6532906B2 - Installation structure of precast wall column - Google Patents

Description

  The present invention relates to the installation structure of a precast wall column installed along the side edge of a concrete floor slab.

  Conventionally, a wall made of concrete is installed at the side end in the bridge width direction of the road bridge. The wall height column mainly serves to prevent a fall of a vehicle from a road bridge, to prevent a deviation, and to guide the driver of a traveling vehicle. The wall height column is generally constructed by so-called cast-in-place concrete where reinforcing bars and forms are assembled on site. In particular, even in the case where the wall column is damaged due to a collision of a traveling vehicle or the wall column itself is deteriorated, repair or replacement is often performed with cast-in-place concrete as well.

  However, since the construction period will be longer at this on-site strike, in recent years, the pre-cast wall column made in advance in a factory etc. is carried into the site and installed along the side edge of the concrete floor slab. It is supposed to be built frequently.

  As a conventional method of installing a precast wall column, for example, the technology described in Patent Document 1 is disclosed. According to the technology disclosed in Patent Document 1, a through hole is formed from the bottom of a reinforced concrete wall column, and a mortar is injected into the through hole after an anchor bar protruding upward from the floor plate is inserted. It is done.

  Moreover, also in patent document 2, a bolt insertion hole is formed in the lower end part of the concrete wall column made into a precast concrete member, and the anchor bolt made to project upwards from the floor slab is inserted in the said bolt insertion hole. And a technique for filling a mortar into the bolt insertion hole is disclosed.

  The techniques disclosed in Patent Documents 1 and 2 are expected to stably join a concrete wall column to a floor slab by firmly attaching a mortar to an anchor bolt or the like.

  However, according to the techniques disclosed in these Patent Documents 1 and 2, when the precast wall column is deteriorated and an external force is applied due to a collision of a vehicle, etc., the anchor bolt can be easily pulled out from the mortar attached. In some cases, Also, when such external force is applied, the mortar may be pulled out with the anchor bolt attached, and further, part of the concrete of the wall column attached to the mortar may be split together. In some cases, it may get caught. That is, there is a problem that the durability against the external force applied to the wall can not be improved only by the disclosed techniques of Patent Documents 1 and 2.

  For this reason, in Patent Document 3, when the precast wall material receives an external pressure in the horizontal direction, the external pressure is transmitted to the side end of the floor slab to avoid the occurrence of breakage due to shear stress. There is also disclosed a configuration in which a shear key is provided.

  However, even when such a shear key is temporarily provided, it can not be said that the desired durability can always be exhibited when a large external force is applied to the wall by only this.

JP 2001-226912 A JP, 2015-71907, A JP, 2016-160690, A

  Therefore, the present invention has been made in view of the above-mentioned problems, and the purpose of the present invention is to install a precast wall column installed along the side edge of a concrete floor slab, in particular, the wall An object of the present invention is to provide a precast wall balustrade installation structure capable of exhibiting strong durability even when a large external force is applied to the balustrade.

In the installation structure of the precast wall column according to the first aspect of the present invention, in the installation structure of the precast wall column installed along the side edge of the concrete floor slab, the concrete floor slab includes only the upper surface and the upper and lower ends of the side edge. An anchor bolt formed to have a large diameter is projected upward, and the precast wall column is inserted into the bolt hole of a shape in which the diameter is increased as it goes upward from the bottom surface aging curable material is filled so as to surround the outer from the outer peripheral side of the bolt holes, the spiral reinforcement that the anchor bolts only upper and lower ends are formed such that the large diameter to restrain that the pulled out from the bolt holes It is characterized in that it is embedded.

In the installation structure of the precast wall column according to the second invention, in the first invention, the upper surface of the side end portion of the concrete floor slab and the bottom surface of the precast wall column are provided with shear keys for transmitting horizontal shear force to each other. In the concrete floor slab, the shear key has a convex portion whose central portion is raised in a convex shape in a cross section in the bridge width direction, and a central portion in a concave shape in a cross section of the bottom surface of the precast wall The bolt holes are formed on the upper surface of the recess at intervals, and the time-hardening material is between the upper surface of the concrete floor slab and the bottom surface of the precast wall box, It is characterized by being filled through a bolt hole .

According to a third aspect of the present invention, in the precast wall column of the second aspect of the present invention, the precast wall column is a hole for injecting and discharging a time-hardening material inclined downward from the bolt hole toward the outer surface. Are provided with an interval at the top and bottom.

In the installation structure of the precast wall column according to the fourth invention, in the second invention or the third invention, the upper surface of the concrete floor slab and the bottom surface of the precast wall column are respectively inclined downward toward the bridge width direction outer side It is characterized by becoming.

Installation structure of precast wall railings according to the fifth invention, in any one of the first invention to the fourth invention, the precast wall railing is the haunch portion is raised in a convex shape than the other areas of the concrete slab It is characterized by being installed on top.

  According to the present invention having the above-described configuration, a substantially horizontal external force directed outward from the side of the road is applied to the precast wall column installed at the side end of the concrete floor slab, for example, due to a collision of a vehicle. In the case, it exerts a remarkable effect. That is, when an external force is applied, a force acts to pull the anchor bolt when the precast wall column 1 is inclined to the outside, which acts on the time-hardening material for the anchor bolt. It can be countered through strong adhesion. In particular, since the upper end of the anchor bolt is provided with a round nut having a larger diameter, it is possible to exert the pullout preventing effect by being locked to the time-hardenable material.

  At this time, by forming a screw or fine unevenness from the upper end to the lower end of the anchor bolt, the adhesion to the time-hardenable material can be enhanced, and the pull-out prevention effect of the anchor bolt can be enhanced. . Similarly, the adhesion to the time-hardenable material can be enhanced by forming fine irregularities and the like on the inner peripheral surface of the bolt hole. As a result, it is possible to prevent the time-hardening material from being pulled out of the bolt hole together with the anchor bolt.

  Further, according to the present invention, spiral reinforcing bars are embedded so as to surround the bolt holes. If a force to pull out the anchor bolt acts, it is possible to counter it through the inward restraining force acting on the bolt hole through the spiral reinforcing bar.

  In addition to this, some of the concrete that constitutes the precast wall column adhering to the time-hardenable material may act to split and pull out together, but the inward restraint force via the spiral rebar By doing this, it is possible to suppress such concrete splitting itself.

It is a perspective view of the precast wall column to which this invention is applied, and the concrete floor slab in which this is installed. It is a front sectional view of a precast wall column to which the present invention is applied and a concrete floor slab on which this is installed. It is a sectional side view of a precast wall column to which the present invention is applied and a concrete floor slab on which the column is installed. It is a figure for demonstrating the setting method of the precast wall column to which this invention is applied. It is a figure for describing other embodiment of the precast wall column to which this invention is applied. It is a block diagram of the tension test system for performing experimental verification. It is a figure for demonstrating the steel bar for a test for performing experimental verification. It is a figure shown about the result of the experimental verification by a tension test system.

  Hereinafter, an embodiment for carrying out an installation structure of a precast wall height column to which the present invention is applied will be described in detail with reference to the drawings.

  FIG. 1 is a perspective view of a precast wall box 1 to which the present invention is applied and a concrete floor slab 2 on which this is installed, FIG. 2 is a front sectional view thereof, and FIG. 3 is a side sectional view thereof. The precast wall column 1 is disposed along the lateral end of the concrete floor slab 2 in the bridge width direction. The precast wall column 1 is extended in the bridge axial direction of the concrete floor slab 2.

  The precast wall height column 1 has an elongated shape whose longitudinal direction is the vertical direction, and is made of so-called reinforced concrete in which reinforcing bars 21 and 22 are embedded. Among them, the reinforcing bars 22 are constituted by a plurality of bars extending linearly in the bridge axis direction. Further, the reinforcing bars 21 are extended in the vertical direction so that the reinforcing bars 22 are inscribed, and the upper and lower ends are bent in an arc shape. The side surface of the precast wall column 1 includes a road side 1a facing the road and an outer side 1b facing the outside of the road bridge.

  Such a reinforced concrete precast wall column 1 is further surrounded by a bolt hole 11, a hole 12 and a hole 13 communicating with the bolt hole 11, a spiral reinforcing bar 14 embedded around the bolt hole 11, and a reinforcing bar 21. And the cable 17 provided in the area to be Further, the bottom surface of the precast wall column 1 includes a recess 18 recessed upward, a first bottom 19a extending from the recess 18 toward the road side surface 1a, and a recess 18 to the outer surface 1b. And a second bottom 19b extended toward the end.

  The concrete floor plate 2 includes an anchor bolt 3 and a spiral reinforcing bar 24 embedded around the anchor bolt 3. On the upper surface of the side end in the bridge width direction in the concrete floor slab 2, a convex portion 28 provided to be convex upward and a first upper portion 29a extended from the convex portion 28 to the road side surface 1a And a second upper portion 29b extended from the convex portion 28 toward the outer side surface 1b.

  The bolt holes 11 are configured as holes cut from the bottom surface of the precast wall column 1. The bolt hole 11 is configured to be larger in diameter than the outer diameter of the anchor bolt. The bolt holes 11 are shaped to be expanded in diameter toward the upper side, so to speak, to be a three-dimensional shape such as a truncated cone or a truncated pyramid, but it is not limited thereto. That is, the bolt holes 11 may have a cylindrical or rectangular shape without diameter expansion or diameter reduction in the vertical direction, or regular or irregular diameter expansion or diameter reduction may be performed. . Furthermore, fine irregularities and the like may be formed on the inner peripheral surface of the bolt hole 11. In addition, although the bolt hole 11 shown in FIG. 1 is configured as a hole cut to the upper side from the recess 18 to the last, in a configuration in which the recess 18 is not provided intentionally, any part of the bottom of the precast wall column 1 is It may be provided.

  The holes 12 are holes for connecting the outer surface 1 b of the precast wall column 1 and the bolt holes 11. The hole 12 is a hole continuing upward in the bolt hole 11 and is provided for discharging a time-hardening material including a non-shrink mortar and the like from the bolt hole 11. The holes 12 may be inclined downward from the bolt holes 11 toward the outer side surface 1 b or the road side surface 1 a.

  The hole 13 is a hole for connecting the outer surface 1 b of the precast wall column 1 and the bolt hole 11. The hole 13 is continued downward from the bolt hole 11 and is provided for injecting a time-hardening material including a non-shrink mortar and the like into the bolt hole 11. The hole 13 may be inclined downward from the bolt hole 11 to the road side surface 1a or the outer side surface 1b.

  The spiral reinforcing bar 14 is a reinforcing bar which is bent in a spiral shape in advance. The spiral reinforcing bar 14 is disposed so as to surround the bolt hole 11 from the outer peripheral side of the bolt hole 11. The spiral reinforcing bars 14 are embedded in advance in the concrete constituting the precast wall column 1.

  The cable 17 is a cable used to connect the precast wall sections 1 adjacent to each other in the bridge axial direction. Specifically, the cable 17 is embodied as various cables such as a carbon fiber cable, a PC steel material, a stainless steel material, and a steel cable. A cable hole (not shown) for inserting the cable 17 is bored in each precast wall column 1. When joining the adjacent precast wall bales 1, the cable 17 may be inserted into the cable hole (not shown), and tension may be applied to the cable 17 as necessary.

  As shown in FIG. 3, the recesses 18 are provided with bolt holes 11 on the upper surface at intervals in the bridge axial direction. The first bottom 19a is inclined downward toward the road side 1a. The second bottom 19 b is inclined downward toward the outer side surface 1 b. In other words, the first bottom 19a and the second bottom 19b slope downward toward the bridge width direction.

  The anchor bolt 3 is configured by screwing round nuts 31 from the upper and lower sides to a steel bar in which a screw is formed at least at the upper and lower ends. By screwing such round nuts 31 on the upper and lower sides of the anchor bolt 3, it is possible to counteract the pull-out force of the anchor bolt 3 itself. The form of the anchor bolt 3 is not limited to the above-described example, and any metal rod may be substituted as long as at least the upper and lower ends are formed to be large in diameter. It is also good. For example, an end band rebar having a large-diameter band crimped to the upper and lower ends of the rebar may be used.

  The lower half of the anchor bolt 3 is embedded in the concrete constituting the concrete floor plate 2. As a result, the upper half of the anchor bolt 3 protrudes upward from the upper surface of the concrete floor slab 2. The upper half of the protruded anchor bolt 3 is inserted into the bolt hole 11. Since the bolt hole 11 is larger in diameter than the anchor bolt 3, the anchor bolt 3 is loosely fitted to the bolt hole 11. The time-hardening material such as non-shrink mortar is filled in the bolt hole 11 in which the loosely fitted anchor bolt 3 is inserted.

  The spiral reinforcing bar 24 is a reinforcing bar bent in advance in a spiral shape, like the spiral reinforcing bar 14. The spiral reinforcing bar 24 is disposed so as to surround the anchor bolt 3 from the outer peripheral side of the bolt hole 11. The spiral reinforcing bars 24 are embedded in the concrete floor slab 2 in advance.

  The convex portion 28 is provided so that the position in the bridge width direction is aligned with the concave portion 18 as shown in FIG. The first upper portion 29a is inclined downward toward the road side surface 1a. The second bottom 19 b is inclined downward toward the outer side surface 1 b. In other words, the first upper portion 29a and the second upper portion 29b are inclined downward toward the bridge width direction outer side.

  When actually installing the precast wall column 1 at the side end of the concrete floor slab 2, the convex portion 28 is made to face the concave portion 18, the first upper portion 29a is made to face the first bottom portion 19a, and the second upper portion 29b is made After facing the second bottom 19b, a time-hardening material such as non-shrink mortar or resin mortar is filled between them.

  Next, an installation method of the precast wall box 1 to which the present invention is applied will be described.

  First, as shown in FIG. 4 (a), it starts from the state where the construction of the concrete floor slab 2 is completed. In this state, the upper half of the anchor bolt 3 protrudes upward from the upper surface of the concrete floor slab 2.

  Next, the precast wall column 1 manufactured in advance at the factory is carried into the site. Then, as shown in FIG. 4B, the convex portion 28 faces the concave portion 18, the first upper portion 29a faces the first bottom portion 19a, and the second upper portion 29b faces the second bottom portion 19b. Are temporarily held apart from each other.

  Next, as shown in FIG. 4C, the temporally curable material 5 is injected from the holes 13. The time-hardening material 5 is injected into the hole 13 through a hose 91. The time-hardening material 5 injected from the hole 13 reaches the bolt hole 11 and is filled so as to fill the anchor bolt 3 inserted therein. The filled time-hardening material 5 hardens and firmly adheres to the anchor bolt 3 and also adheres firmly to the bolt hole 11. As a result, the bolt hole 11 and the anchor bolt 3 are firmly connected to each other through the hardened time-hardening material 5, and thus the precast wall column 1 is firmly installed to the concrete floor plate 2. Is possible. The time-hardenable material 5 may be injected from between the first upper portion 29a and the first bottom portion 19a.

  In addition, the time-hardening material 5 that has reached the bolt holes 11 is the concave portion 18 that constitutes the bottom of the precast wall column 1 as it is, the first bottom 19a, the second bottom 19b, and the convex that constitutes the upper surface of the concrete floor slab 2 28 also flows between the first upper portion 29a and the second upper portion 29b. As a result, the time-hardening material 5 is also filled between the bottom surface of the precast wall column 1 and the upper surface of the concrete floor plate 2, and the time-hardening material 5 hardens to bond them firmly to each other. The Rukoto.

  By the way, the precast wall column 1 is placed on the top of the concrete floor slab 2 with the time-hardenable material 5 laid in advance, and the time-hardenable material 5 is injected from the holes 12 thereon to make the inside of the bolt hole 11 It may be filled with this time-hardening material 5.

  A case will be considered in which a substantially horizontal external force directed outward from the road side surface 1a is applied to the precast wall column 1 installed at the side end of the concrete floor slab 2 in this way, for example, due to a collision of a vehicle. In such a case, when the precast wall column 1 is inclined to the outside, a force to pull out the anchor bolt 3 acts, but against this force the strength of the time-hardenable material 5 against the anchor bolt 3 is strong. It can be countered through good adhesion. In particular, since the round nut 31 having a larger diameter is provided at the upper end of the anchor bolt 3, it is possible to exert the pull-out preventing effect due to the fact that this is locked to the time-hardenable material 5.

  At this time, by forming the screw or fine unevenness from the upper end to the lower end of the anchor bolt 3, the adhesion to the time-hardenable material 5 can be enhanced, and the pull-out prevention hardening of the anchor bolt 3 is enhanced. be able to. Similarly, the adhesion to the time-hardenable material 5 can be enhanced by forming fine irregularities or the like on the inner peripheral surface of the bolt hole 11. As a result, it is possible to prevent the time-hardening material 5 from being pulled out of the bolt hole 11 together with the anchor bolt 3.

  Furthermore, according to the present invention, a spiral reinforcing bar 14 is embedded so as to surround the bolt hole 11. If a force to pull out the anchor bolt 3 acts, it can be countered through the inward restraining force acting on the bolt hole 11 through the spiral reinforcing bar 14.

  In addition to this, some of the concrete constituting the precast wall column 1 attached to the time-hardenable material 5 may act to split and pull out together, but the inward facing through the spiral reinforcing bar 14 By exerting a restraining force, it is possible to suppress such concrete splitting itself.

  Further, in the present invention, the concrete floor slab 2 is similarly provided with the spiral reinforcing bars 24 around the anchor bolt 3 so that the force of the anchor bolt 3 trying to pull out can be countered, and furthermore, the anchor It is possible to firmly prevent the concrete around the bolt 3 from being pulled out together by splitting it.

  Furthermore, in the installation structure of the precast wall column 1 to which the present invention is applied, the convex portion 28 faces the concave portion 18, the first upper portion 29a faces the first bottom portion 19a, and the second upper portion 29b faces the second bottom portion 19b. Then, a time-hardening material such as non-shrink mortar is filled between them. As a result, when external force is applied in the horizontal direction, it is possible to cause the facing convex portion 28 and the concave portion 18 to act as a shear key capable of resisting so-called shear stress. That is, when an external force directed outward from the road side surface 1 a is applied, a shearing force acts between the concave portion 18 and the convex portion 28. By the projection 28 being in the recess 18, the shearing force can be countered.

  Further, according to the present invention, moisture is externally applied by inclining the holes 12 downward toward the outer side surface 1b and by inclining the holes 13 downward toward the road side surface 1a and the outer side surface 1b. It becomes possible to make it the structure which corrosion factors, such as salt content, can not enter easily. That is, since the hole 12 and the hole 13 are inclined upward toward the bolt hole 11, corrosion is prevented substantially from entering the bolt hole 11 for a corrosion factor which is going to intrude from the outside. As a result, since the corrosion factor hardly enters the bolt hole 11, it is possible to prevent the anchor bolt 3 inserted inside from being corroded.

  FIG. 5 shows another embodiment of the precast wall box 1 to which the present invention is applied. In this embodiment, the convex portion 28, the first upper portion 29a, and the second upper portion 29b constituting the upper surface of the concrete floor slab 2 are configured as a so-called hunting portion 20 which is raised in a convex shape than other regions. is there. By configuring such a hunting portion 20, it is possible to prevent the corrosion factor from infiltrating through the holes 13 more firmly.

  Hereinafter, an experiment conducted to verify the operation and effect of the precast wall column 1 to which the present invention is applied will be described. FIG. 6 shows a tensile test system 6 for performing experimental verification. In this tensile test system 6, a hydraulic jack 62 provided with a load cell 61, a load beam 63 made of H-shaped steel, a concrete specimen 64, and bolt holes 65 formed in the concrete specimen 64 are used. The non-shrinkage mortar 71 is filled after the test steel bar 70 inserted is inserted into the bolt hole 65. Further, a displacement gauge 72 is attached to the steel bar 70. The displacement meter 72 is set at the top end of the concrete specimen 64 before the test, and is set so that the displacement becomes zero at no load.

  Between the loading beam 63 and the concrete specimen 64, a reaction piece 73 is provided. That is, in this tensile test system 6, it becomes possible to estimate the load which the anchor bolt 3 pulls out in the form which inserted the anchor bolt 3 in the bolt hole 11 in this invention, and filled the time-hardenable material 5.

  When a tensile stress is applied to the steel bar 70 via the hydraulic jack 62 in such a tensile test system 6, the stress is measured via the load cell 61 and the displacement of the steel bar 70 is measured via the displacement gauge 72. It becomes possible to detect.

  In this embodiment, a test piece A in which a threaded portion is formed at the end of a stainless steel bar as shown in FIG. 7 and a round screw is screwed on the end of a steel bar 70 for test, and It experimented about the test body B which consists of an end band rebar in which the end part of the formed bar was made to form an end band, and the test body C which consists of a bar which nothing is provided at an end.

  The experimental results are shown in FIG. In each graph, the horizontal axis is the relative displacement from the top end of the concrete specimen 64, and indicates the displacement of the steel bar 70. The vertical axis is the load measured by the load cell 61. The designed tensile force calculated for each and the yield tensile force are also shown in the graph.

  It was shown that the test specimen A can maintain durability up to the yield tensile force (105.6 kN) over the designed tensile force. It was shown that the test body B can maintain durability up to the yield tensile force (98.8 kN) beyond the designed tensile force.

  On the other hand, the test sample C yielded when a load of 14.2 kN was applied, and could not exhibit sufficient durability even for the designed tensile force.

  From the above experimental results, it has been found that the end of the steel bar 70 can exhibit durability against tensile stress by at least an increase in diameter.

Reference Signs List 1 precast wall column 1a road side 1b outer side 2 concrete floor plate 3 anchor bolt 5 time-hardening material 6 tensile test system 11 bolt hole 12, 13 hole 14 spiral rebar 17 cable 18 recess 20 hunches 21 and 22 rebar 24 spiral rebar 28 Convex part 31 Round nut 61 Load cell 62 Hydraulic jack 63 Load beam 64 Concrete specimen 65 Bolt hole 70 Bar steel 71 Non-shrink mortar 72 Displacement gauge 73 Reactive piece

Claims (5)

In the precast wall column installation structure installed along the side edge of the concrete deck,
An anchor bolt formed so that only the upper and lower ends are larger in diameter from the upper surface of the side end portion of the concrete floor slab is projected upward,
The precast walls railings over time curable material together with the anchor bolt is inserted is filled with respect to the bolt holes of the shape of a larger diameter toward the bottom upwards, surrounding the outside from the outer peripheral side of the bolt holes As described above, the installation structure of a precast wall balustrade characterized in that a spiral rebar is embedded which restricts the anchor bolt formed so that only the upper and lower ends become larger in diameter from being pulled out from the bolt hole . The upper surface of the side end of the concrete floor slab and the bottom surface of the precast wall column are provided with a shear key for transmitting a horizontal shear force to each other ,
The shear key, by recessing a protruding portion which center portion is raised into a convex shape at the bridge width direction cross section, the central portion in the bridge width direction cross section of the bottom surface of the precast walls railings concavely in the concrete slab Consisting of a recess and
The bolt holes are formed at intervals on the upper surface of the recess,
Furthermore, a time-hardening material is filled between the upper surface of the concrete floor slab and the bottom surface of the precast wall box via the bolt holes, and the installation structure of the precast wall box according to claim 1. . The aforementioned pre-cast walls railings, claims, characterized in that the hole for be injected and discharged over time curable material which is inclined downwardly toward the outer side from the bolt holes are provided at intervals in the vertical Installation structure of the precast wall column of 2 statement. The installation structure of the precast wall column according to claim 2 or 3, wherein the upper surface of the concrete floor slab and the bottom surface of the precast wall column are inclined downward toward the bridge width direction. The precast wall height column according to any one of claims 1 to 4 , wherein the precast wall height column is installed on a hunched portion raised in a convex shape more than other regions of the concrete floor slab. Installation structure of the wall column.

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