JP2011080293A - Seismic response controlled bridge pier - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a seismic response controlled bridge pier which is easily maintained and is excellent in durability, workability, and economical efficiency. <P>SOLUTION: RC rod-like dampers 21 also serving as connecting members are installed in a form similar to the intermediate beams between RC columns 2 constituting the seismic response controlled bridge pier 1. In the RC rod-like dampers 21, reinforcing bars 22 for energy absorption or PC steel extending in a longitudinal direction are embedded in concrete, and the end sections of the RC rod-like dampers 21 are inserted in the restricting holes 24 of circular restricting pipes 23 having a circularly formed inner surface. When the RC columns 2 are bent and deformed by an earthquake, such bending deformations as to cause vertical displacements occur in the RC rod-like dampers 21, and the reinforcing bars 22 etc. in the RC rod-like dampers 21 are elastically deformed to absorb vibration energies generated at the earthquake. The deformation of the RC columns 2 thereby falls within an elastic range even at the time of, for example, a level 2 earthquake. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a seismic control pier in which a damper for absorbing energy during an earthquake is incorporated in a pier having a column structure or a wall structure.

  The applicant of the present application has made the pier member thinner than the continuous rigid frame bridge to make the natural period longer, thereby reducing the response speed of the pier during an earthquake and incorporating a vibration control device such as a steel plate damper. We have developed seismic piers that absorb energy (see Patent Document 1 and Non-Patent Document 1).

  As a typical form of the above-mentioned seismic control pier, a plurality of columns are connected by a truss to form a truss structure column, and the truss between the columns is separated to the left and right at the truss rating point in the center between the columns, A steel plate damper is placed at the truss rating point and the left and right trusses are connected to convert the horizontal displacement of the column during the earthquake into a vertical displacement of the truss rating point position. There is one that absorbs seismic energy by displacement.

  In addition, the applicant of the present application is composed of RC members and the like as a damper for a structure that has durability and weather resistance that can be applied even in a poor environment such as a coastal area and that can also follow temperature expansion and contraction. A rod-shaped damper structure has been developed (see Patent Document 2).

  The rod-shaped damper is fixed to the structure at both ends, and absorbs energy by bending deformation of the rod-shaped damper due to relative displacement of the structure. A rod-shaped damper main body made of an RC member or a PC member; A cylindrical member fixed to the structure and having a restraining hole into which an end portion of the rod-shaped damper is inserted. The inner surface of the restraining hole has a rod-shaped damper on the inner surface from the base portion toward the tip portion. A curved surface is formed by an arc that separates from the outer surface.

  The constraining hole is, for example, a morning glory that extends upward with an arc that matches the ultimate curvature of the rod-shaped damper body, and when a horizontal force such as inertial force from the upper structure during an earthquake acts on the upper portion of the rod-shaped damper, According to the shape of the constraining hole, the ultimate rotation angle of the rod-shaped damper, that is, the deformation performance can be greatly improved by controlling the curvature distribution and dispersing the bending deformation.

JP-A-2005-207111 JP 2008-240488 A JP 2008-214973 A

“HiFleD pier construction method -High Flexibility and Damping- Damping pier construction method using steel dampers”, [online], Kashima Construction Co., Ltd., [Search June 29, 2009], Internet <http: //www.kajima.co.jp/tech/c_bridge/structure/04/index.html>

  The conventional seismic control pier described above has the following problems.

(1) Braces, truss members and energy absorbing devices (steel plate dampers, etc.) installed in the surface of the RC frame structure are steel members, which require regular maintenance such as rust prevention treatment, and have a life cycle cost. To increase.

(2) The steel brace must be installed during or after the RC column construction and the damper member must be set after the steel brace is installed, which complicates the construction work.

(3) Considering cost reduction, a standard damper is desirable, but the required performance of the damper varies depending on the scale of the vibration control pier, so it is likely to be a custom product and is not economical.

  The present invention is intended to solve the above-described problems, and an object thereof is to provide a vibration control pier that is easy to maintain and is excellent in durability, workability, and economy.

  The invention according to claim 1 of the present application is a bridge pier having a column structure or a group wall structure in which a plurality of columns or walls are coupled by a plurality of coupling members spanned between the columns or walls. As described above, a bar-shaped damper having an RC structure or a PC structure in which a reinforcing bar or a PC steel material extending in the longitudinal direction as an energy absorbing material is coated with a concrete material is used.

  A rod-shaped damper is usually one in which a plurality of rebars or PC steel is embedded in the longitudinal direction of the concrete, but unlike reinforced concrete or prestressed concrete as a structural member, rebar or PC steel is used as an energy absorber, It is designed to absorb seismic energy by plastic deformation of rebar and PC steel against bending and tensile forces caused by shear. In order to increase energy absorption efficiency, a low yield point steel rebar can be used as the rebar.

  Since the reinforcing steel or PC steel material, which is an energy absorbing material in the rod-shaped damper, is coated with concrete, it is excellent in weather resistance and does not need to be subjected to rust prevention treatment.

  In addition, since it can be used as a beam as a connecting member for connecting thin columns or walls constituting the assembled column or the assembled wall, design and construction are easy.

  Although this rod-shaped damper can use what was commercialized as a damper member single item, it can also perform on-site construction similar to the case of a reinforced concrete beam or a prestressed concrete beam. However, although it is possible to function as a connecting member as a connecting member, reinforcing bars and PC steel materials are energy absorbing materials to the last, and therefore, cross-sectional designs and reinforcing bars as energy absorbing materials.

  According to a second aspect of the present invention, in the vibration control pier according to the first aspect, an end portion of the rod-shaped damper is inserted into a cylindrical constraining member that limits a bending deformation amount of the rod-shaped damper, and the constraining member is the column. Or it is provided in the wall.

  In Claim 1, the cylindrical restraining member is not essential, but the end of the rod-like damper is restrained by the tubular restraining member as in Claim 2, and the amount of bending deformation of the rod-like damper is controlled. As in the case of the rod-shaped damper described in Document 2, it is possible to exert a large energy absorption capability while preventing the rod-shaped damper from being damaged.

  Further, by providing the restraining member on the column or wall, it can be used as the mounting portion of the rod-shaped damper as it is.

  According to a third aspect of the present invention, in the vibration control pier according to the second aspect, the constraining member has a constraining hole into which an end portion of the rod-shaped damper is inserted, and an outer surface of the rod-shaped damper is formed on the inner surface from the base portion toward the tip portion. It is characterized by forming an arcuate curved surface that goes away from.

  By designing the arcuate curved surface, it is possible to uniformly deform the reinforcing bar or the PC steel material as the energy absorbing material over the longitudinal direction of the rod-shaped damper, and to exert the maximum deformation performance and energy absorbing ability.

  According to a fourth aspect of the present invention, in the vibration control pier according to the second or third aspect, an end portion of the rod-shaped damper is attached to the restraining member.

  Claim 4 assumes the case where the end of the rod-shaped damper is housed in the restraining member, and the rod-like member attached to the restraining member by attaching the restraining member to the pillar or wall constituting the assembled column or the assembled wall. The damper is installed at a predetermined position.

  According to a fifth aspect of the present invention, in the vibration-damping pier according to the fourth aspect, the restraining member is integrated with the column or the wall, and the rod-shaped damper is detachable from the restraining member. To do.

  In this case, it is possible to replace only the rod-shaped damper main body portion that can be attached to and detached from the restraining member. Moreover, construction is also facilitated by integrating the restraining member in advance with the pillar or wall of the vibration control pier.

  According to a sixth aspect of the present invention, in the vibration control pier according to the first, second, or third aspect, the rod-shaped damper is attached by being inserted into a through hole formed in the column or the wall. .

  The sixth aspect assumes that the end of the rod-shaped damper passes through the restraining member and is housed in a column or wall that is a part of the structural member, and in terms of fixing the rod-shaped damper, fits in the restraining member. More advantageous than the case.

  In this case, the rod-shaped damper can be attached so as to penetrate the column or wall from the opposite side of the column or wall.

(1) The seismic control piers, including the dampers, are all made of concrete, eliminating the need for cycle work such as rust prevention, and reducing costs (including life cycle costs). Basically, it is maintenance-free with regard to durability.

(2) For rod-shaped damper members, repair work after an earthquake becomes easy by adopting a replaceable mounting method.

(3) The installation of the rod-shaped damper can be performed simultaneously with the construction of the assembled column or the assembled wall. Also, the steel member for installing the damper is not necessarily embedded in the column or wall constituting the assembled column or the assembled wall. This is advantageous in terms of shortening the construction period, improving workability, and improving the stability of quality.

(4) For rod-shaped dampers, energy absorption performance and deformation performance can be controlled by designing the curvature, bar arrangement, dimensions, etc. of the arc constraining part, so customized dampers are manufactured and installed for each pier and each installation location. be able to.

It is a perspective view which shows the basic structure (Example 1) of the seismic control pier of this invention. FIG. 5 shows a seismic control pier as Example 2 of the present invention, in which (a) is a front view in a normal state, and (b) is a front view showing a deformed state at the time of an earthquake. It is a perspective view which shows the precast-type arc restraint part of RC rod-shaped damper in Example 3. FIG. (a)-(d) is a perspective view which shows the precast-type circular arc restraint part in the modification of Example 3, respectively. It is sectional drawing which shows the attachment method of RC rod-shaped damper in Example 4. It is sectional drawing which shows the attachment method of RC rod-shaped damper in Example 5. FIG. It is sectional drawing of the circular arc restraint part in case manufacture and installation of a circular arc restraint part are performed simultaneously with construction of RC pillar as Example 6. FIG. It is sectional drawing of the circular arc restraint part in case an arc restraint part is manufactured as a precast member as Example 7, and it installs at the time of construction of RC pillar. It is sectional drawing of the circular arc restraint part in the case of producing an arc restraint part as a precast member as Example 8, and installing at the time of construction of RC pillar. It is sectional drawing of the circular arc restraint part in case the arc restraint part is manufactured as a precast member as Example 9, and it installs after construction of RC pillar. It is sectional drawing of the circular arc restraint part in case the arc restraint part is manufactured as a precast member as Example 10, and it installs after construction of RC pillar. The dimensional relationship between the reinforcing bar of RC rod-shaped damper and the circular arc restraint pipe is shown as a reference. (A) is a sectional view in the axial direction, and (b) is a sectional view in the direction perpendicular to the axial direction.

  FIG. 1 shows a basic form of the present invention as Example 1, and an RC rod-shaped damper 11 that also serves as a connecting member between a plurality of RC columns 2 constituting a seismic control pier 1 having a column structure. It is installed as an intermediate beam.

  In this case, the appearance is similar to that of a normal RC structure column, but the energy absorbing rebar 12 (shown by a broken line) in the RC rod-shaped damper 11 as a connecting member is not a reinforcing bar as an RC beam, but more than a predetermined value. The seismic energy is absorbed by the plastic deformation in response to the earthquake response, and the response of the vibration control pier 1 is reduced.

  Although the RC rod-shaped damper 11 can be manufactured at a factory, it can also be constructed on site by using cast-in-place concrete in the same manner as a conventional RC beam.

  Since this RC rod-shaped damper 11 can realize any characteristics depending on its own dimensions and bar arrangement, it is necessary to install a minimum number of dampers customized to the optimum characteristics for each damping bridge pier. Can be efficient.

  Further, the RC rod-shaped damper 11 basically has durability equal to or higher than that of a normal RC member, so that all of the vibration control piers 1 are made of concrete to reduce cyclic maintenance work. it can.

  In addition, it replaces with an assembly pillar, and the way of thinking is the same also when it uses an assembly wall structure.

  FIG. 2 shows a case where RC rod-shaped dampers 21 that also serve as connecting members are installed as intermediate beams between a plurality of RC columns 2 constituting the seismic control pier 1 having a column structure. ) Is the normal state, and (b) is the deformation state during the earthquake (exaggerated).

  FIG. 12 shows the dimensional relationship between the reinforcing bars of the RC rod-shaped damper 21 (axial direction stripes 22a and spiral stripes 22b) and an arc constraining tube 23 to be described later. As the axial direction stripes 22a, FIG. For example, ten SD490 D19 bars are arranged, and a spiral line 22b of SD295 D10 is tightly wound around it.

  The spiral line 22b is disposed so as to prevent the RC rod-shaped damper 21 from being sheared and to bend and deform stably. Similarly, in the case of a rectangular cross section, a shear reinforcing bar such as an axial bar and a spiral bar is arranged.

  In the four columnar structure shown in FIG. 1, although not shown, the base of the column is fixed by the foundation structure, and the upper end is fixed by the main girder. Even if a horizontal force in an arbitrary direction is received due to an earthquake, each RC rod-shaped damper 21 receives only a bending deformation in one direction.

  Therefore, it can also be set as a rectangular cross section. In the rectangular cross section, since the axial rebar 22a or the PC steel material may be disposed only in the upper and lower sides (or left and right) of the cross section with respect to the necessary bending direction, the steel material can be mechanically most efficiently disposed with respect to the bending.

  On the other hand, the circular cross-section is easy to manufacture and has the same characteristics in any bending direction, so that even when the column structure is subjected to torsion, stable bending deformation occurs and functions as a damper. Can do.

  As in the first embodiment, the main body portion of the RC rod-shaped damper 21 in the second embodiment is the one in which the reinforcing steel 22 for absorbing energy or the PC steel material extending in the longitudinal direction is embedded in the concrete, Is inserted into a restraint hole 24 of a cylindrical restraint pipe (hereinafter referred to as “arc restraint pipe”) 23 formed in an arc shape.

  The RC rod-shaped damper 21 according to the second embodiment can be installed by fixing the arc constraining pipe 23 to the side surface of the RC column 2 constituting the assembled column of the vibration control pier 1. The fixing method is not particularly limited, such as a bolt joint using a joint fitting or a method of constructing the arc constraining tube 23 integrally with the RC pillar 2.

  The basic function as a seismic control pier is the same as that of the conventional seismic control pier described in Patent Document 1 and Non-Patent Document 1 described in the background section, and the RC column 2 is bent and deformed. When this occurs, bending deformation is applied to the RC rod-shaped damper 21 so as to shift up and down (see FIG. 2B), and the reinforcing bars 22 and the like in the RC rod-shaped damper 21 are plastically deformed to absorb vibration energy during an earthquake. To do. Thereby, for example, it is assumed that the deformation of the RC column 2 is within the elastic range even during a level 2 earthquake.

  In addition, since the RC rod-shaped damper 21 can realize arbitrary characteristics depending on its own dimensions and bar arrangement, a minimum number of dampers customized to the optimum characteristics for each damping bridge pier are installed. This is possible as described in the first embodiment. Furthermore, in the case of the second embodiment, it is possible to adjust the deformation performance and energy absorption performance of the entire damper by the arc shape of the inner surface of the arc constraining tube 23.

  FIG. 3 shows a case where the end portion of the RC rod-shaped damper 31 main body is constrained by a precast arc constraining portion 33 as a specific embodiment of the RC rod-shaped damper 31.

  The arc constraining portion 33 is configured so that the RC rod-shaped damper installation portion 34 can be covered with a detachable RC lid 35 (in the drawing, 37 and 38 indicate mounting holes). Further, the arc portion has a U-shaped box opening structure so that the RC rod-shaped damper 31 main body can be slid and installed from the side. Thereby, replacement | exchange of the RC rod-shaped damper 31 main body damaged by the earthquake etc. becomes easy.

  It is preferable that the upper and lower side surfaces of the arc constraining portion 33 have a haunch shape or a curved surface shape. This is a device for gently transmitting the horizontal force of the RC rod-shaped damper 31 transmitted through the arc portion to the RC column portion. Thereby, it is also possible to reduce the size of the arc restraint portion 33.

  The installation surface of the arc constraining portion 33 on the RC pillar 2 can be provided with irregularities so as to function as a shear key. Further, when the arc constraining portion 33 is a precast member, it is possible to enhance the integrity with the RC pillar 2 by installing a perforated steel plate gibber 36 or an anchor bar (not shown) as a connecting member. .

  In this example, since the damper is deformed in one direction, the energy absorbing rebar 32 is embedded as a rectangular cross section. For example, as shown in FIGS. 4 (a) to 4 (d) as modifications of the third embodiment. A circular section may be sufficient.

  Further, the removable cover 35 may take other forms depending on the shape of the arc restraining portion 33. That is, FIG. 4 (a) has a form in which the arc constraining portion 33a and the RC lid 35a are divided into two. In FIG. 4B, the RC lid 35b has a minimum width in which the RC rod-shaped damper 31b can be installed (taken out).

  Similarly, FIG. 4 (c) shows a form in which the arc restraint portion 33c and the RC lid 35c are divided into two. In FIG. 4 (d), the RC lid 35d has a minimum width in which the RC rod-shaped damper 31d can be installed (taken out).

  FIG. 5 shows, as a specific embodiment of the RC rod-shaped damper 41, a case where the end of the RC rod-shaped damper 41 main body is constrained by an arc confining portion 43 with an installation path.

  That is, as shown in FIG. 4B, the installation path 44 of the RC rod-shaped damper 41 is provided from the arc restraint portion 43 to the side surface. In this case, if the RC rod-shaped damper 41 having a circular cross section is inserted from the insertion port 45 on the side surface of the column, it rolls downward and can be automatically installed on the arc constraining portion 43.

  If the step 46 is provided at the boundary between the arc constraining portion 43 and the installation path 44 or if the stopper 47 is provided after the RC rod damper 41 is installed, the RC rod damper 41 will not move to the side during an earthquake. Moreover, when exchanging the RC rod-shaped damper 41 after the earthquake, the RC rod-shaped damper 41 can be removed by moving the RC rod-shaped damper 41 along the installation path 44 or cutting the central portion of the RC rod-shaped damper 41 with a crane or the like. is there.

  In this method, if the arc constraining portion 43 and the installation path 44 can be provided at the time of the construction of the RC pillar 2, the RC rod-shaped damper 41 can be installed very easily. On the other hand, there is a possibility that the installation part may be enlarged.

  FIG. 6 shows, as a specific embodiment of the RC rod-shaped damper 51, a case where the end portion of the RC rod-shaped damper 51 main body is restrained by an arc restraint portion 53 with an insertion path.

  That is, an insertion path for installing the RC rod-shaped damper 51 is provided in the RC column 2, and the RC column 2 on the left side in the drawing has a through-hole 2 a (diameter: RC rod-shaped damper 51 of the RC rod-shaped damper 51. The outer diameter + α) is provided from the inside and outside of the frame. The RC rod-shaped damper 51 is inserted and installed until it hits into the hole 2b of the RC pillar 2 on the opposite side.

  In this method, since the penetration depth of the RC rod-shaped damper 51 can be secured in the RC pillar 2, the height of the arc constraining portion 53 can be reduced. On the other hand, if the member diameter of the RC rod-shaped damper 51 is large, the through hole 2a and the hole 2b become large, and there is a possibility that the main reinforcing bar and the like of the RC column 2 part are affected. It is suitable for RC columns with large depth and small RC rod-like dampers such as RC wall type piers, or RC columns with large main reinforcing bar spacing.

  Regarding the arc constraining portion, there are a method of manufacturing the RC column 2 at the same time as the construction and a method of manufacturing as a precast member and installing it after the RC column 2 is constructed. An example of a method for producing the installation simultaneously with the construction of the RC pillar 2 is shown.

  The outside of the arc constraining portion 63 is formed in a haunch shape so as to gently transmit the horizontal force from the RC rod-shaped damper to the RC column 2. Further, the reinforcing bars 64 as the reinforcing bars and the assembly bars of the arc part of the arc restricting part 63 are fixed in the RC column 2 and integrated.

  In this method, since the damper mounting portion can be manufactured at the time of the construction of the RC pillar 2, it is possible to reduce the work labor as compared with the later installation method described later. However, the shape of the form of the arc constraining portion 63 is complicated, and it is necessary to pay attention to the filling property of the concrete. In this case, if the concrete joint of the RC pillar 2 is directly under each mounting portion, it is advantageous in installing the mold and filling the concrete.

  FIG. 8 shows an example in which the arc constraining portion 73 is manufactured as a precast member and is installed when the RC pillar 2 is constructed. As shown in the figure, the precast arc restraint portion 73 is provided with a perforated steel plate gibel 74 at the connection portion with the RC column 2 and is embedded by embedding them when the RC column 2 is placed in concrete. .

  It is also effective to provide an unevenness on the installation surface of the arc constraining portion 73 with the RC pillar 2 so as to function as a shear key.

  If the arc constraining portion 73 can be installed at the time of the construction of the RC pillar 2, the vertical movement of the construction machine or the worker can be reduced for the installation work after the construction, which is efficient.

  FIG. 9 shows a method of manufacturing the arc constraining portion 83 as a precast member and installing it at the time of construction of the RC pillar 2 as in the seventh embodiment. As shown in the figure, the precast arc restraint portion 83 is provided with a plurality of anchor bars 84 having a protrusion 85 as a fixing body at the tip at the connection portion with the RC pillar 2, and the concrete of the RC pillar 2 is provided. Installation is carried out by burying them when placing.

  As in the seventh embodiment, it is also effective to provide unevenness on the installation surface of the arc constraining portion 83 with the RC pillar 2 so as to function as a shear key. Moreover, if the arc restraint part 83 can be installed at the time of the construction of the RC pillar 2, the vertical movement of the construction machine or the worker can be reduced for the installation work after the construction, which is efficient.

  FIG. 10 shows an example in which the arc restraint portion 93 is manufactured as a precast member and is installed after the construction of the RC pillar 2.

  As a method for fixing the arc constraining portion, an excavation hole 94 is provided in the RC column 2 in a later work, an anchor bar 95 embedded in the arc constraining portion 93 is inserted, and a filler (for example, non-shrink mortar or epoxy resin) is used. Integrate.

  FIG. 11 shows an example in which the arc constraining portion 103 is manufactured as a precast member and installed after the construction of the RC pillar 2 as in the ninth embodiment.

  As a method of fixing the arc constraining portion, the RC pillar 2 is provided with a through hole 2c in a post-construction, and the arc constraining portion 103 is also provided with a through hole 104, and the PC steel rod 105 or anchor is provided so as to penetrate both. Insert bolts and fix them by tension and friction by tightening.

  In this case, the arc constraining portion 103 can be removed, and replacement is easy if the arc constraining portion 103 is damaged after an earthquake or due to deterioration over time.

  INDUSTRIAL APPLICABILITY The present invention can be used as a seismic pier with a column structure or a wall structure.

1 ... Aseismic bridge pier,
2 ... RC pillar, 2a ... through hole, 2b ... hole, 2c ... through hole,
11, 21, 31, 41, 51, 61 ... RC rod damper,
12, 22, 32, 42, 52 ... rebar for energy absorption,
23 ... Circular restraint tube, 24 ... Restraint hole,
33 ... Precast type arc restraint part, 34 ... RC rod-shaped damper installation part, 35 ... RC lid, 36 ... Perforated steel plate gibel, 37, 38 ... Mounting hole,
43 ... Arc restraint part, 44 ... Installation path, 45 ... Inlet, 46 ... Step, 47 ... Stopper
53 ... Arc restraint part,
63 ... arc restraint part, 64 ... rebar,
73 ... Precast arc restraint part, 74 ... Perforated steel plate gibber,
83 ... Precast arc restraint part, 84 ... Anchor bar, 85 ... Projection part,
93 ... Precast arc restraint part, 94 ... Drilling hole, 95 ... Anchor bar,
103 ... Precast arc restraint part, 104 ... Through hole, 105 ... PC steel rod

Claims (6)

  It is a bridge pier of an assembled column structure or an assembled wall structure formed by connecting a plurality of columns or walls with a plurality of connecting members spanned between the columns or walls, and as the connecting member, in the longitudinal direction as an energy absorbing material A seismic control pier characterized by using a RC-type or PC-structured bar-shaped damper formed by covering extending steel bars or PC steel with a concrete material.   The end of the rod-shaped damper is inserted into a cylindrical constraining member that limits the amount of bending deformation of the rod-shaped damper, and the constraining member is provided on the column or wall. Seismic control pier as described.   The constraining member has a constraining hole into which an end portion of the rod-shaped damper is inserted, and has an arcuate curved surface going away from the outer surface of the rod-shaped damper from the base portion toward the tip portion on the inner surface. The vibration control pier according to claim 2, wherein   4. The damping pier according to claim 2, wherein an end of the rod-shaped damper is attached to the restraining member.   The seismic control pier according to claim 4, wherein the restraining member is integrated with the column or wall, and the rod-shaped damper is detachable from the restraining member.   4. The damping pier according to claim 1, wherein the rod-shaped damper is attached by being inserted into a through-hole formed in the column or wall.

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