JP2013199764A - Earthquake proof/vibration suppression member installation structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an earthquake proof/vibration suppression member installation structure capable of increasing earthquake energy that an earthquake proof/vibration suppression member absorbs at low cost.SOLUTION: An earthquake proof/vibration suppression member installation structure 1 includes an upper base plate 16 provided on an upper end of a vibration suppression stud 14, an upper opposite base plate 16a arranged across an upper slab 13, a fastening member 20 connecting the base plates 16, 16a to each other, a lower base plate 17 provided on a lower end of the vibration suppression stud 14, a lower opposite base plate 17a arranged across a lower slab 13, and a fastening member 20 connecting the base plates 17, 17a to each other. A high strength part 30 formed of mortar is formed between the upper base plate 16 and upper opposite base plate 16a, and between the lower base plate 17 and lower opposite base plate 17a. The high strength part 30 has higher strength than the slab 13, and is provided to at least a part of the slab 13 in plain view.

Description

  The present invention relates to an earthquake / damping member installation structure. Specifically, the present invention relates to an earthquake-resistant / damping member installation structure in which an earthquake-resistant / damping member for suppressing vibration of a building due to an earthquake or strong wind is installed between upper and lower beams of an existing building.

Conventionally, in order to suppress large deformation of the column beam frame that occurs in the event of an earthquake, existing vibration beam design members will be newly added to the existing building designed based on the old earthquake resistance design standards. Has been done.
As the vibration-proof member, for example, a vibration-damping brace provided with a hydraulic damper, a vibration-damping stud installed between beams on the upper and lower floors constituting the column beam frame, and the like are employed.

Among these, the vibration control pillar is added to an existing building having a steel column beam frame, for example.
This existing building has a pair of adjacent columns, a pair of upper and lower steel beams installed between the pair of columns, and a pair of upper and lower slabs formed on each of the pair of steel beams.

  Damping studs are installed between upper and lower steel beams. For example, hydraulic dampers, viscous bodies, viscous elasticity, etc. that attenuate horizontal displacement between upper and lower studs made of H-shaped steel. And one end of the hydraulic damper is integrated with the upper stud and the other end is integrated with the lower stud.

  An upper base plate is provided at the upper end of the stud so as to contact the lower surface of the flange of the steel beam on the floor directly above the floor where the stud is installed. A slab upper facing base plate is installed on the upper surface of the slab on the immediately upper floor, and the upper base plate and the upper facing base plate are connected by a fastening member.

  A lower base plate is provided at the lower end of the stud so as to contact the upper surface of the slab on the floor where the stud is installed. A lower facing base plate is installed on the lower surface of the flange of the steel beam on the floor where the studs are installed, and the lower base plate and the lower facing base plate are connected by a fastening member that penetrates the slab.

  According to the above-described vibration control stud, the hydraulic damper absorbs the seismic energy during an earthquake, and the seismic force borne by the column beam frame can be suppressed.

Japanese Patent No. 4161593

By the way, there is a case where it is desired to further increase the seismic energy absorbed by the above-mentioned vibration control pillar. In this case, it is necessary to increase the tension introduced into the binding member and to join the frame of the existing building and the vibration control stud with high rigidity. Therefore, when the tension force introduced into the binding member is increased, the compressive stress acting on the slab increases, and the slab may be damaged.
In order to solve this problem, a method of increasing the concrete frame on the existing slab, a method of removing the existing slab and placing a new slab or welding the fastening member to the beam can be considered. However, there was a problem that the construction cost was high.

  An object of this invention is to provide the earthquake-resistant / damping member installation structure which can increase the earthquake energy absorbed by an earthquake-resistant / damping member at low cost.

  The earthquake-resistant / damping member installation structure according to claim 1 (for example, an after-mentioned earthquake-resistant / damping member installation structure 1) has upper and lower beams (for example, an after-mentioned steel frame) of an existing building (for example, an existing building 10 to be described later). An anti-seismic / damping member installation structure in which an anti-seismic / damping member (for example, a post-damping pillar 14 described later) for suppressing vibration of the building is installed between the beams 12). An upper base plate (for example, an upper base plate 16 to be described later) provided at the upper end portion and an upper counter base plate (for example, an upper base plate disposed to face the upper base plate with an upper slab (for example, upper slab 13 to be described later) interposed therebetween) An upper facing base plate 16a) described later, a tightening member (for example, a tightening member 20 described later) for connecting the upper base plate and the upper facing base plate, and the seismic / vibration suppressing portion. The lower base plate (for example, lower base plate 17 described later) and the lower slab (for example, lower slab 13 described later) are disposed to face the lower base plate with a lower slab (for example, lower slab 13 described later) interposed therebetween. A lower facing base plate (for example, a lower facing base plate 17a described later) and a tightening member (for example, a tightening member 20 described later) for connecting the lower base plate and the lower facing base plate. Between the base plate and the upper counter base plate, and between the lower base plate and the lower counter base plate, a high strength portion (for example, a high strength portion 30 described later) formed of mortar is formed, The high-strength portion is higher in strength than the slab and is provided in at least a part of the slab in plan view. That.

  The earthquake-resistant / damping member installation structure according to claim 2, wherein the high-strength portion forms the high-strength portion due to the degree of compressive stress generated in the high-strength portion by introducing a tension force to the binding member. It is set so that it may become smaller than the allowable compressive stress degree of mortar.

  In the earthquake-resistant / damping member installation structure according to claim 3, the test section of the high-strength portion is at least one of the lower surface of the lower base plate and the upper surface of the upper flange of the beam.

Here, the earthquake-resistant / damping member is an earthquake-resistant member and a vibration-damping member, and is a member that suppresses vibration or deformation of the building due to an earthquake or strong wind.
The seismic members include a stud that gives rigidity to the building and suppresses deformation of the building during an earthquake or strong wind, and a stud that suppresses vibration in the vertical direction.
The damping member includes a member that absorbs a force applied to the building such as a damper, a viscous body, and a viscoelastic body, and a device that applies a force against the force applied to the building.

  In addition, the degree of compressive stress includes those caused by reaction of tension force by introducing tension force to the binding member, and those caused by pressure bearing action via the base plate.

  According to this invention, the high intensity | strength part formed with the mortar was formed between the base plate and the opposing base plate. Therefore, since the allowable compressive stress of the slab increases, the tension introduced into the fastening member can be increased, and the column beam frame of the existing building and the seismic / damping member can be joined with high rigidity. As a result, the seismic energy absorbed by the earthquake-resistant / damping member can be increased.

Further, the slab was cored, and then a high strength portion was formed by pouring mortar into the cored portion.
Therefore, the required compressive strength can be easily realized simply by adjusting the drilled cross-sectional area of the core, so that the construction becomes easy.
Moreover, since a high-strength part can be constructed only in the core removal operation and mortar filling operation, the construction can be completed in a short period of time, and the construction cost can be kept low.

Also, if the core is removed at a position directly above the upper flange of the beam, when filling the mortar, a mold for receiving the mortar is not required, so that the construction efficiency is further improved.
The upper surface of the beam contacts the bottom surface of the high-strength portion, the side surface contacts the concrete of the slab, and the base plate contacts the upper surface. Thereby, since this high intensity | strength part is restrained from four directions, when the compressive force is received from an up-down direction, strength expression more than the design value of a mortar can be anticipated.

According to the present invention, the high-strength portion made of mortar is formed between the base plate and the counter base plate. Therefore, since the allowable compressive stress of the slab increases, the tension introduced into the fastening member can be increased, and the column beam frame of the existing building and the seismic / damping member can be joined with high rigidity. As a result, the seismic energy absorbed by the earthquake-resistant / damping member can be increased. Further, the slab was cored, and then a high strength portion was formed by pouring mortar into the cored portion.
Therefore, the required compressive strength can be easily realized simply by adjusting the drilled cross-sectional area of the core, so that the construction becomes easy. Moreover, since a high-strength part can be constructed only in the core removal operation and mortar filling operation, the construction can be completed in a short period of time, and the construction cost can be kept low. Also, if the core is removed at a position directly above the upper flange of the beam, when filling the mortar, a mold for receiving the mortar is not required, so that the construction efficiency is further improved. The upper surface of the beam contacts the bottom surface of the high-strength portion, the side surface contacts the concrete of the slab, and the base plate contacts the upper surface. Thereby, since this high intensity | strength part is restrained from four directions, when the compressive force is received from an up-down direction, strength expression more than the design value of a mortar can be anticipated.

It is sectional drawing of the existing building 10 to which the earthquake-proof and damping member installation structure 1 which concerns on 1st Embodiment of this invention was applied. It is AA sectional drawing of FIG. It is an expanded sectional view of the upper end part and lower end part of the vibration suppression stud which concerns on the said embodiment. It is BB sectional drawing of FIG. It is a sectional side view of the damping brace concerning 2nd Embodiment of this invention. It is CC sectional drawing of FIG.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description of the embodiments, the same constituent elements are denoted by the same reference numerals, and the description thereof is omitted or simplified.
[First Embodiment]
FIG. 1 is a cross-sectional view of an existing building 10 to which the seismic / damping member installation structure 1 according to the first embodiment of the present invention is applied. FIG. 2 is a cross-sectional view taken along the line AA of FIG.

The existing building 10 includes a pair of adjacent steel pipe columns 11, a steel beam 12 made of a pair of upper and lower H-shaped steels laid between the pair of steel tube columns 11, and a pair of steel beams 12. A pair of upper and lower slabs 13 formed.
Between the upper and lower steel beam 12, a damping column 14 as an earthquake-resistant / damping member extending in a substantially vertical direction is installed at a substantially intermediate position between the steel pipe columns 11. The vibration control pillars 14 suppress vibrations during an earthquake and are connected to other vibration control pillars 14 on the upper and lower floors.

  The vibration suppression studs 14 are provided between the upper studs 14a extending in the substantially vertical direction, the lower studs 14b extending in the substantially vertical direction, and the upper studs 14a and the lower studs 14b. And a hydraulic damper 15 for absorbing.

  One end 15a of the hydraulic damper 15 is integrated with the upper stud 14a, and the other end 15b is integrally connected with the lower stud 14b.

3 and 4 are enlarged cross-sectional views of the upper end portion and the lower end portion of the damping stud 14.
A rectangular plate-like upper base plate 16 disposed on the lower surface of the lower flange 12b of the upper steel beam 12 is provided at the upper end portion of the vibration damping stud 14.
In addition, a rectangular plate-like upper facing base plate 16a is disposed on the upper surface of the upper slab 13, and a plurality of (in this embodiment, a total of twelve) upper base plates 16 and upper facing base plates 16a are fastened together. Tightened with a member 20.

The binding member 20 includes a PC steel bar 21 penetrating the slab 13, the upper base plate 16, and the upper opposing base plate 16a, and a fixing tool 22 attached to the upper and lower ends of the PC steel bar 21.
A predetermined tension force is introduced into the PC steel bar 21, thereby causing a compressive stress in the upper slab 13.

The lower end portion of the damping interphase 14 also has substantially the same structure as the upper end portion of the damping interphase 14. In other words, the lower base plate 17 disposed on the upper surface of the lower slab 13 is provided at the lower end of the vibration control pillar 14.
In addition, a rectangular plate-like lower opposing base plate 17a is disposed on the lower surface of the lower flange 12b of the lower steel beam 12, and there are a plurality of lower base plates 17 and lower opposing base plates 17a (in the present embodiment). , A total of 12) of the fastening members 20.

The binding member 20 includes a PC steel bar 21 penetrating the slab 13, the lower base plate 17, and the lower opposing base plate 17a, and a fixing tool 22 attached to the upper and lower ends of the PC steel bar 21.
A predetermined tension force is introduced into the PC steel bar 21, thereby causing a compressive stress in the lower slab 13.

  In the present embodiment, since the vibration suppression pillars 14 are connected to the other vibration suppression pillars 14 on the upper and lower floors, the upper opposing base plate 16a becomes the lower base plate 17 of the upper floor vibration suppression pillars 14 and becomes the lower opposing base plate. Reference numeral 17a denotes an upper base plate 16 of the vibration damping stud 14 on the lower floor.

  Between the upper flange 12a and the lower flange 12b of the upper and lower steel beams 12, a plurality (in this embodiment, three each on both sides across the web) so as to be located in the plane of the base plates 16 and 17 The reinforcing member 18 made of a square steel pipe is interposed. In addition, each reinforcement member 18 is arrange | positioned so that the PC steel rod 21 mentioned later may be located in the both ends of the longitudinal direction in planar view.

  Further, high-strength mortar (grout) is filled between the upper facing base plate 16a and the upper slab 13 and between the lower base plate 17 and the lower slab 13.

Further, a high-strength mortar is formed between the upper base plate 16 and the upper opposing base plate 16a of the upper slab 13 and between the lower base plate 17 and the lower opposing base plate 17a of the lower slab 13. A high-strength portion 30 is formed (indicated by hatching in FIGS. 1 to 4). In the present embodiment, six high-strength portions 30 are formed.
The high-strength portion 30 is formed by coring the slab 13 at a position directly above the upper flange 12a of the steel beam 12, and then filling the core-stripped portion with high-strength mortar.

The total cross-sectional area and mortar strength of the high-strength portion 30 are obtained by the following procedure.
That is, first, the upper surface of the upper slab 13 between the upper base plate 16 and the upper face the base plate 16a, and assayed section S _1. Further, the lower end surface of the lower slab 13 between the lower base plate 17 and the lower face the base plate 17a and the test section S _2.
Next, an average degree of compressive stress acting on each of the test sections S ₁ and S ₂ is determined by the tension of the binding member.
Finally, the total cross-sectional area or mortar strength of the high-strength portion is set so that the average compressive stress level of the test sections S ₁ and S ₂ is smaller than the long-term compressive stress level of the slab concrete.

Here, the average compressive stress degree σ _S in the test sections S ₁ and S ₂ is expressed by the following formula (1).

In the formula (1), N is a total tension force acting on the test sections S ₁ and S ₂ by the binding member. A _S is the horizontal cross-sectional area at the test sections S ₁ and S ₂ . _AC is the total cross-sectional area of the high-strength portion in the test cross-section.
Further, γ is an additional coefficient when the compressive strength of the high strength mortar is replaced with equivalent slab concrete strength. This γ is expressed by the following formula (2).

Wherein (2), F _C is the design strength of the concrete slab, F C _'is a design strength of high-strength mortar.

Then, the following equation (3) as is established may be set test section S _1, design strength of the total cross-sectional area A _C or high-strength mortar high-strength portion of S ₂ F _{C '.}
Just do it.

  In formula (3), α is a coefficient for obtaining the long-term allowable compressive stress degree of concrete, and is defined as α = 1/3 in the Building Standard Act Enforcement Ordinance Article 91.

Hereinafter, the test section S _1, indicating whether the study example slab has sufficient strength.
Tensile strength of PC steel bar 300kN / piece Number of PC steel rods 12 Base plate 400mm x 1330mm
Concrete design standard strength (Fc) 21 N / mm ²
Coefficient (α) for determining the long-term allowable compressive stress of concrete 1/3
Design strength of high strength mortar (Fc ') 60 N / mm ²
Core diameter 150mm
6 core removal points 150mm slab thickness
Steel beam width 200mm

From the above, N = PC steel bar tension force × PC steel bar number = 300 kN / bar × 12 bar = 3600 kN. Further, _{f c} long becomes ^{1/3 × 21N / mm 2} = 7N / mm 2.
γ is 1.86 becomes, _{A S} is a 75 × 75 × π × 6 = 106028mm 2.

First, the test section _{S 1,} the area _{A S} of compressive stress is generated is a 400mm × 1330mm = 532000mm ^2.
Therefore, the average compressive stress degree σ _S of the test section S ₁ is obtained according to the following formula (4).

Since the average compressive stress σ _S is smaller than the _fc long-term, it can be said that the slab has sufficient strength in the verification section S ₁ .

Next, a study example on test section S _2. Area _{A S} of compressive stress is generated is a 200mm × 1630mm = 326000mm ^2.
Therefore, the average compressive stress degree σ _S of the test section S ₂ is obtained by the following equation (5).

Since the average compressive stress degree σ _S is smaller than the _fc long-term, it can be said that the slab has sufficient strength in the verification section S ₂ . Therefore, based on the results of this study, by providing six high-strength portions with a diameter of 150 mm and a mortar strength Fc ′ = 60 N / mm ² , the average compressive stress level generated in the test sections S ₁ and S ₂ can be determined over the long-term allowable compression of slab concrete. It was confirmed that it could be smaller than the stress level.

According to this embodiment, there are the following effects.
(1) A high-strength portion 30 made of high-strength mortar was formed on the slab 13 between the base plates 16 and 17 and the opposing base plates 16a and 17a. Therefore, since the allowable compressive stress of the slab 13 is increased, the tension force introduced into the fastening member 20 can be increased, and the column beam frame and the damping inter-column 14 of the existing building 10 can be joined with high rigidity. As a result, the seismic energy absorbed by the vibration suppression pillar 14 can be increased.

(2) The slab 13 was cored, and then a high-strength mortar was poured into the cored portion to form the high-strength portion 30.
Therefore, the required compressive strength can be easily realized simply by adjusting the drilled cross-sectional area of the core, so that the construction becomes easy.
In addition, since the high-strength portion 30 can be constructed only in the core removal work and the filling work of the high-strength mortar, the construction can be completed in a short period of time, and the construction cost can be kept low.

In addition, by coring at a position directly above the upper flange 12a of the steel beam 12, when filling high-strength mortar, there is no need for a mold for receiving the mortar, and the construction efficiency is further improved.
Moreover, since the high intensity | strength part 30 is restrained from four directions, when the compressive force is received from the up-down direction, the intensity | strength expression more than the design value of a mortar can be anticipated.

[Second Embodiment]
FIG. 5 is a side sectional view of a vibration damping brace 40 as an earthquake resistant / damping member according to the second embodiment of the present invention. 6 is a cross-sectional view taken along the line CC of FIG.
The damping brace 40 has a hydraulic damper 15 provided at a substantially middle position between the steel pipe columns 11 of the lower slab 13, and a substantially V-shape from one end 15 a of the hydraulic damper 15 toward the upper steel beam 12. A brace body 41 extending in the direction.

At the upper end of the brace body 41, a rectangular plate-like upper base plate 16 disposed on the lower surface of the lower flange 12b of the upper steel beam 12 is provided.
A lower base plate 17 disposed on the upper surface of the lower slab 13 is provided at the other end 15 b of the hydraulic damper 15.
In this embodiment, the upper surface of the upper slab 13 between the upper base plate 16 and the upper face the base plate 16a, and assayed section S _1. Further, the lower end surface of the lower slab 13 between the lower base plate 17 and the lower face the base plate 17a and the test section S _2.

  According to this embodiment, the same effects as the above (1) to (2) are obtained.

It should be noted that the present invention is not limited to the above-described embodiment, and modifications, improvements, etc. within a scope that can achieve the object of the present invention are included in the present invention.
For example, in the above-described embodiment, the hydraulic damper 15 is provided in the vibration suppression pillar 14, but is not limited thereto. For example, instead of the hydraulic damper 15, a viscoelastic damper may be provided between the upper stud 14a and the lower stud 14b, or a hysteresis damping damper in which a low yield point steel is joined to the web portion of the H-section steel. It may be a vibration control pillar.

  In the present embodiment, the total cross-sectional area or mortar strength of the high-strength portion is set based on the long-term compressive stress level of the slab concrete, but the present invention is not limited to this. You may set the total cross-sectional area or mortar intensity | strength of a high intensity | strength part on the basis of a short-term compressive stress degree.

  Moreover, in this embodiment, although the slab 13 was cored and the high intensity | strength part 30 was formed by filling this cored part with high intensity | strength mortar after that, it is not restricted to this. For example, a high-strength portion is formed by filling a high-strength mortar with a predetermined thickness between the upper facing base plate 16a and the upper slab 13 or between the lower base plate 17 and the lower slab 13. Alternatively, the high strength portion may be formed by cutting the slab 13 and filling the cut portion with high strength mortar.

DESCRIPTION OF SYMBOLS 1 ... Earthquake-resistant / damping member installation structure 10 ... Existing building 11 ... Steel pipe column 12 ... Steel beam 12a ... Upper flange 12b ... Lower flange 13 ... Slab 14 ... Damping column (seismic / damping member)
14a ... Upper stud 14b ... Lower stud 15 ... Hydraulic damper (damping mechanism)
DESCRIPTION OF SYMBOLS 15a ... One end part of a hydraulic damper 15b ... Other end part of a hydraulic damper 16 ... Upper base plate 16a ... Upper counter base plate 17 ... Lower base plate 17a ... Lower counter base plate 18 ... Reinforcement member 20 ... Tightening member 21 ... PC steel rod 22 ... Fixing tool 30 ... High-strength part S1, S2 ... Test section 40 ... Damping brace (seismic / damping member)
41 ... Brace body

Claims (3)

A seismic / damping member installation structure in which an anti-seismic / damping member is installed between the upper and lower beams of an existing building,
An upper base plate provided at the upper end of the seismic / damping member;
An upper facing base plate disposed to face the upper base plate with the upper slab interposed therebetween;
Tightening member that connects the upper base plate and the upper counter base plate;
A lower base plate provided at the lower end of the seismic / damping member;
A lower opposing base plate disposed to face the lower base plate across the lower slab;
A binding member that connects the lower base plate and the lower opposing base plate,
Between the upper base plate and the upper counter base plate, and between the lower base plate and the lower counter base plate, a high-strength portion formed of mortar is formed,
The high-strength portion is stronger than the slab, and is provided in at least a part of the slab in a plan view.   The high-strength portion is set so that the compressive stress level generated in the high-strength portion by introducing a tension force to the binding member is smaller than the allowable compressive stress level of the mortar forming the high-strength portion. The earthquake-resistant / damping member installation structure according to claim 1.   The seismic / vibration control member installation structure according to claim 2, wherein the test section of the high-strength portion is at least one of a lower surface of the lower base plate and an upper surface of the upper flange of the beam.

Images