JP2011162978A - Joint structure of precast concrete member and structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a joint structure of a precast concrete member, which exhibits a damping effect by changing the rigidity of the member based on earthquake information without using a variable damper, and to provide a structure. <P>SOLUTION: When a control unit 50 determines by calculation that a big earthquake occurs, the control unit 50 controls pump members 46 to supply oil into cylinder members 30 through through-holes 42 and discharges the oil in the cylinder members 30 through the through-holes 40. Thereby the piston members 32 are moved to release the tensions of steel wires 24, reducing the pressing forces of beam members 16 and a column member 14. The rigidity of the structure 10 is reduced, causing the entire part of the structure 10 to be deformed, with the structure 10 vibrating at a long period. Thereby, the resonance of a ground and the structure 10 which are vibrated by the large earthquake can be suppressed. Thus, the damping effect can be exhibited by changing the rigidity of the member based on the earthquake information. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a joint structure of precast concrete members and a structure provided with the joint structure of precast concrete members.

  Patent Document 1 describes a vibration suppression control method for improving the seismic isolation performance by changing the characteristics of the variable damping damper based on the earthquake information obtained from the P wave at the early stage of the earthquake occurrence.

JP 2006-45885 A

  However, in the conventional method, since a variable damping damper is used, a space for installing the variable damping damper is required separately.

  An object of the present invention is to exhibit a damping effect by changing the rigidity of a member based on earthquake information without using a variable damping damper.

  The precast concrete member joining structure according to claim 1 of the present invention is a precast concrete column member, a pressure bonding means for pressure bonding the end face of the precast concrete beam member to the joint portion of the column member, A pressure-bonding force changing means for changing the pressure-bonding force of the pressure-bonding means; and a control means for changing the pressure-bonding force of the pressure-bonding means by controlling the pressure-bonding force changing means based on the P wave at the early stage of the earthquake. It is characterized by that.

  According to the above configuration, the control unit changes (weakens) the pressure-bonding force of the pressure-bonding means by controlling the pressure-bonding force changing means based on the P wave at the initial stage of the earthquake. By weakening the pressure-bonding force of the beam member to the column member, the rigidity of the upper and lower layers of the joint portion of the column member is reduced, and the rigidity of the layer of the structure composed of the beam and the column is reduced. As a result, the natural period of the structure becomes longer.

  In this way, by increasing the natural period of the structure, the natural period of the structure becomes longer than the dominant period of a large earthquake, and resonance is suppressed. Thereby, the input energy to the structure at the time of a large earthquake can be reduced and the damping effect can be exhibited.

  The joint structure of the precast concrete member according to claim 2 of the present invention is the joint structure according to claim 1, wherein the crimp joint means is fixed to the beam members on both sides through the joint portion of the column member, It is a tension member that exerts a crimping force by applying a force, and the crimping force changing means is provided on a specific tension member, and includes the beam member and the column member provided with the pressure changing means. The structure layer is provided with a vibration damping device that deforms and absorbs seismic energy.

  According to the said structure, a tension | tensile_strength member penetrates the joint part of a pillar member, is fixed to the beam member of both sides, and exhibits a crimping force by giving tension | tensile_strength.

  In addition, the crimping force changing means is provided on a specific crimping joining member, and the structure layer composed of the beam member and the column member provided with the crimping force changing means is deformed to absorb seismic energy. A vibration damping device is provided.

  Thus, by weakening the pressure-bonding degree of a specific layer, the bending rigidity of the upper and lower layers of that layer can be reduced, and a longer period can be achieved by deforming that layer.

  Moreover, the vibration damping device installed in the layer of the structure composed of the beam member and the column member provided with the crimping force changing means effectively absorbs the seismic energy.

  According to a third aspect of the present invention, there is provided a structure having the precast concrete member joining structure according to the first or second aspect.

  According to the above configuration, by providing the joint structure of the precast concrete member according to claim 1 or 2 to the structure, the structure can be reduced by reducing the rigidity of the upper and lower layers of the joint portion in the column member at the time of a large earthquake. The vibration control effect that reduces the input energy to the structure at the time of a large earthquake can be exhibited by extending the period.

It is sectional drawing which showed the joining structure of the precast concrete member which concerns on 1st Embodiment of this invention. It is sectional drawing which showed the joining structure of the precast concrete member which concerns on 1st Embodiment of this invention. (A) (B) It is sectional drawing which showed the crimping force change apparatus etc. which were used for the joining structure of the precast concrete member which concerns on 1st Embodiment of this invention. (A) (B) It is the side view which showed the joining structure of the precast concrete member which concerns on 1st Embodiment of this invention. It is the side view showing the structure concerning a 1st embodiment of the present invention. It is the side view showing the structure concerning a 1st embodiment of the present invention. It is the graph used for demonstrating the characteristic of the structure concerning 1st Embodiment of this invention, Comprising: It is drawing which showed the acceleration spectrum of the earthquake on the vertical axis | shaft, and the period on the horizontal axis. (A) (B) It is the side view which showed the joining structure of the precast concrete member which concerns on 2nd Embodiment of this invention. It is the side view which showed the structure which concerns on 2nd Embodiment of this invention. It is the side view which showed the modification of the structure based on 2nd Embodiment of this invention. It is the side view which showed the modification of the structure based on 2nd Embodiment of this invention. (A) (B) It is the side view which showed the joining structure of the precast concrete member which concerns on 3rd Embodiment of this invention.

  An example of a joint structure of precast concrete members according to the first embodiment of the present invention and a structure provided with the joint structure of precast concrete members will be described with reference to FIGS. In the figure, the arrow UP indicates the upper side in the vertical direction.

(overall structure)
As shown in FIG. 5, the structure 10 is constructed by a plurality of cylindrical piles (not shown) vertically embedded in the ground (GL) and the ground (GL) and supported by the piles. A concrete foundation 12 (hereinafter simply referred to as a foundation 12) is provided.

  Furthermore, the upper side (vertical direction upper side) of the foundation 12 is constructed to include a column member 14 made of precast (hereinafter referred to as PCa) extending in the vertical direction and a beam member 16 made of PCa extending in the horizontal direction. A four-story upper structure 18 is constructed.

(Main part configuration)
Next, a joint structure 38 between the column member 14 made of PCa and the beam member 16 made of PCa will be described.

  As shown in FIGS. 1 and 2, the end face 16 </ b> A of the beam member 16 extending in the horizontal direction is abutted against the joint portions 14 </ b> A on both sides of the column member 14 extending in the vertical direction. And the joint part 14A of the column member 14 and the end surface 16A of the beam member 16 are pressure-bonded and joined by the tension members 20 arranged side by side in the vertical direction (see FIG. 1) and the horizontal direction (see FIG. 2).

  Specifically, the tension member 20 includes a tubular steel pipe member 22 that passes through the joint portions 14A provided on both sides of the column member 14 and is embedded from the end surface 16A of the beam member 16 into the beam member 16, and the steel pipe. And a steel wire 24 inserted through the inside of the member 22.

  Further, a holding member 26 that holds one end of the steel wire 24 in place is provided on one end side of the steel wire 24, and the crimping force applied to the beam member 16 is changed on the other end side of the steel wire 24. A crimping force changing device 28 is provided as the crimping force changing means.

  As shown in FIG. 3A, the crimping force changing device 28 includes a cylindrical cylinder member 30 into which the other end side of the steel wire 24 is inserted and filled with oil, and an inside of the cylinder member 30. And a piston member 32 supported so as to be movable in the longitudinal direction of the steel wire 24 (hereinafter simply referred to as “steel wire longitudinal direction”).

  Further, the piston member 32 has a disk-shaped pressing portion 32A formed along the inner peripheral surface of the cylinder member 30, and a proximal end portion fixed to the pressing portion 32A, and the distal end portion extends in the longitudinal direction of the steel wire. And a cylindrical portion 32B protruding outside the cylinder member 30. And the other end part of the steel wire 24 penetrates the cylindrical part 32B, and protrudes from the front-end | tip part of the cylindrical part 32B.

  The other end portion of the steel wire 24 is provided with a male screw portion 24A in which a male screw is formed, and a nut 36 is fastened to the male screw portion 24A protruding from the tip portion of the cylindrical portion 32B. Thereby, the other end part of the steel wire 24 is moved following the movement of the piston member 32.

  Further, two through holes 40 and 42 are formed on the wall surface of the cylinder member 30 with the pressing portion 32A interposed therebetween. A pump member 46 is provided on the opposite side of the cylinder member 30 across the through holes 40 and 42 to inject oil into or discharge oil from the cylinder member 30 through the through holes 40 and 42. ing.

  With this configuration, when the pump member 46 is operated, oil is injected into the cylinder member 30 from the through hole 42, and the oil in the cylinder member 30 is discharged from the through hole 40, the piston member 32 is shown in FIG. It moves to the arrow direction shown by (2), and the tension | tensile_strength of the steel wire 24 is released (refer FIG.3 (B)). That is, as shown in FIG. 1, by releasing the tension of the steel wire 24, the crimping force of the beam member 16 to the column member 14 is weakened, and the rigidity of the upper and lower layers of the joint portion 14 </ b> A in the column member 14 is reduced. It is supposed to be.

  On the other hand, as shown in FIG. 3B, when the pump member 46 is operated, oil is injected into the cylinder member 30 from the through hole 40, and oil in the cylinder member 30 is discharged from the through hole 42. The piston member 32 moves in the direction of the arrow shown in FIG. 3 (B) to apply tension to the steel wire 24. That is, as shown in FIG. 1, by applying tension to the steel wire 24, the crimping force of the beam member 16 to the column member 14 is increased, and the rigidity of the upper and lower layers of the joint portion 14 </ b> A in the column member 14 is high. It is supposed to be.

  Further, a control unit 50 is provided as control means for controlling the pump member 46 constituting the crimping force changing device 28 to change the crimping force of the crimping force changing device 28. During normal times (when no earthquake occurs), the control unit 50 controls the pump member 46 to move the piston member 32 to the position shown in FIG. The pressure-bonding force of the member 16 to the column member 14 is increased, and the rigidity of the upper and lower layers of the joint portion 14A in the column member 14 is increased.

  On the other hand, the seismic wave includes a P wave (initial tremor) with a high propagation speed and an S wave (main movement) with a large amplitude that causes a large shake although the propagation speed is slow. Then, real-time earthquake information about earthquakes caused by P waves detected near the epicenter at the time of the earthquake is transmitted by the Japan Earthquake Agency's emergency earthquake bulletin (Nowcast) and the Real-time Earthquake Information Utilization System (REIS) of the National Research Institute for Earth Science and Disaster Prevention. Has been.

  As shown in FIG. 5, the structure 10 is provided with a sensor 52 that receives the real-time earthquake information described above via satellite communication or the Internet.

  The control unit 50 (see FIG. 1) is set so that real-time earthquake information from the sensor 52 can be captured at all times, and the earthquake level or the response value of the structure 10 is calculated from the captured real-time earthquake information. Yes.

  Specifically, the control unit 50 incorporates a calculation program using a distance attenuation formula for calculating the maximum acceleration amplitude as the seismic motion level at the construction point of the structure 10 from the real-time earthquake information about the magnitude and the location of the epicenter. .

  As this distance attenuation formula, the following formula is known.

logA = aM _w + b · R + c-log (R + e) D ≦ 30 km
logA = aM _w + b · R + c D> 30 km

Here, A: maximum acceleration response spectrum, M _w : magnitude, R: distance from the epicenter, a, b, c: regression coefficient, e: correction term, D: hypocenter depth.

Then, when the real-time earthquake information about the magnitude _Mw and the epicenter location is taken into the control unit 50, the distance R from the epicenter and the epicenter depth D are calculated from the epicenter location and the location information of the construction point of the structure 10, and From the values of R and D and the magnitude _Mw , the maximum acceleration amplitude of the ground motion at the construction point of the structure 10 is calculated by the distance attenuation formula.

  Based on this result, the control unit 50 controls the pump member 46 to change the crimping force by the crimping force changing device 28.

  As shown in FIG. 4A, in a state where the tension force is applied to the steel wire 24, the pressure-bonding force of the beam member 16 to the column member 14 is increased, and the top of the joint portion 14A in the column member 14 is increased. The rigidity of the lower layer is increased.

  On the other hand, as shown in FIG. 4B, in the state where the tension of the steel wire 24 is released, the appearance of the concrete due to the decrease in bending rigidity and the reduction of the compression axial force due to the disappearance of the tension of the steel wire 24. A decrease in shear stiffness is accompanied by a decrease in the above Young's modulus.

  And in the beam member 16, the bending proof stress falls by the tension | tensile_strength disappearance of the steel wire 24 arises. Thereby, the pressure-bonding force of the beam member 16 to the column member 14 is weakened, the column member 14 and the beam member 16 are relatively movable, and the rigidity of the upper and lower layers of the joint portion 14A in the column member 14 is reduced. It has become.

  The joint structure 38 between the column member 14 and the beam member 16 includes the column member 14, the beam member 16, the tension member 20, the crimping force change device 28, and the control unit 50.

(Action / Effect)
Next, a method for causing the structure 10 to exert a damping effect using the joint structure 38 between the column member 14 and the beam member 16 will be described.

  As shown in FIG. 5, when an earthquake occurs at a certain location, real-time earthquake information obtained from P-waves indicating the initial tremor detected near the epicenter is transmitted from REIS of the National Research Institute for Earth Science and Disaster Prevention. .

  If it does so, the sensor 52 installed in the structure 10 will receive the transmitted real-time earthquake information, and the control part 50 (refer FIG. 1) will take in the real-time earthquake information which the sensor 52 received. Further, the control unit 50 calculates the distance R from the epicenter and the seismic source depth D based on the captured real-time earthquake information, and further calculates the maximum acceleration amplitude of the earthquake motion at the construction point of the structure 10.

  As shown in FIG. 1, when the control unit 50 calculates a large earthquake (for example, seismic intensity of 5 or less), the control unit 50 controls the pump member 46 to change the crimping force by the crimping force changing device 28. .

  Specifically, as shown in FIG. 3A, the control unit 50 controls the pump member 46 to inject oil into the cylinder member 30 from the through hole 42, and into the cylinder member 30 from the through hole 40. Drain the oil. As a result, the piston member 32 is moved in the direction of the arrow shown in FIG. 3A, and the tension of the steel wire 24 is released (see FIG. 3B).

  As shown in FIG. 6, by reducing the rigidity of the entire structure 10, the entire structure 10 is deformed and the structure 10 becomes longer, and the natural period of the structure 10 is longer than the dominant period of a large earthquake. Thus, resonance of the vibrating ground and the structure 10 is suppressed. And by suppressing that the ground and the structure 10 which vibrate by a big earthquake resonate, the input energy to the structure 10 by a big earthquake reduces.

Here, FIG. 7 shows a graph in which the vertical axis indicates the acceleration spectrum of the earthquake and the horizontal axis indicates the period of the earthquake. For example, it is assumed that the period in the range shown by diagonal lines on the graph is the dominant period T ₃ of a large earthquake, and the natural period T ₁ of the structure 10 at the normal time exists in the dominant period T ₃ . By changing the structure 10 from the natural period T ₁ to the natural period T ₂ having a period longer than the dominant period T ₃ (lengthening), the acceleration spectrum received by the structure 10 decreases from a ₁ to a ₂ and is caused by an earthquake. Input energy to the structure 10 is reduced. Thus, it can be seen that the input energy to the structure 10 due to the earthquake is reduced by making the structure 10 longer in a large earthquake. Note that the same idea applies even if the natural period T ₁ of the normal structure 10 does not exist within the dominant period T ₃ of a large earthquake.

  On the other hand, as shown in FIG. 3B, when the large earthquake ends, the control unit 50 controls the pump member 46 to inject oil into the cylinder member 30 from the through hole 40 and from the through hole 42. The oil in the cylinder member 30 is discharged. Thereby, the piston member 32 is moved in the direction of the arrow shown in FIG. 3B, and tension is applied to the steel wire 24 (see FIG. 3A). By applying a tension force to the steel wire 24, the crimping force of the beam member 16 to the column member 14 is increased, the rigidity of the upper and lower layers of the joint portion 14A in the column member 14 is increased, and the structure 10 has a normal rigidity. Return to.

  As described above, by making the structure 10 longer than the dominant period of a large earthquake, the ground that vibrates due to the large earthquake and the structure 10 are suppressed from resonating, and the structure 10 caused by the large earthquake The input energy is reduced and the damping effect can be exhibited.

  In addition, since only a member normally used in precast concrete construction (PCa construction) is used and a special device (for example, a variable damping damper) is not used, space can be effectively used.

  Moreover, since it has the structure which weakens the crimping | compression-bonding force with respect to the column member 14 of the beam member 16 and reduces the rigidity of the structure 10, it suppresses that the harmful | damage damage arises at the edge part of the beam member 16 at the time of a big earthquake. be able to.

  Moreover, since the damage of the edge part of the beam member 16 is suppressed, the rigidity of the structure 10 can be returned to the state (normal state) before the occurrence of the large earthquake by increasing the pressure-bonding force after the earthquake. That is, the continuous usability of the structure 10 can be ensured.

  Moreover, since the whole structure 10 deform | transforms and lengthens by reducing the rigidity of the whole structure 10, the structure of a finishing material can be made the same in each layer (each floor).

  Although the present invention has been described in detail with respect to specific embodiments, the present invention is not limited to such embodiments, and various other embodiments are possible within the scope of the present invention. It is clear to the contractor. For example, in the said embodiment, although the control part 50 controlled the pump member 46 based on the real-time earthquake information transmitted from REIS etc. of National Research Institute for Earth Science and Disaster Prevention, for example, it is provided in the elevator of the structure 10. The control unit 50 may control the pump member 46 based on the P wave detected by the P wave detection device.

  Moreover, in the said embodiment, although the pile foundation was demonstrated as an example about the structure 10, it is not limited to this in particular, About a foundation form, according to the ground condition to locate, a direct foundation, ground improvement, A pile foundation or the like may be selected.

  In the above embodiment, the four-story structure 10 has been described as an example. However, the present invention is not particularly limited thereto, and the technical idea of the present invention can be applied from a low-rise building to a high-rise building.

  Next, an example of a joint structure of precast concrete members according to a second embodiment of the present invention and a structure provided with the joint structure of precast concrete members will be described with reference to FIGS.

  In addition, about the same member as 1st Embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted.

  As shown in FIGS. 8A and 8B, the crimping force changing device 76 provided in the joint structure 72 of the structure 70 is formed by attaching the beam member 16 that supports the floor slab (not shown) on the second floor to the column member 14. It is provided on the tension member 74 that is crimped to the floor, and is not provided on the tension member 74 that supports the floor slabs of other floors. Further, the layer of the structure 70 composed of the beam member 16 and the column member 14 provided with the crimping force changing device 76 is provided with a damping damper 78 as a damping device that deforms and absorbs seismic energy. ing.

  As shown in FIG. 8A, in the state in which the crimping force of the beam member 16 to the column member 14 is increased, the rigidity of the upper and lower layers of the joint portion 14A in the column member 14 is increased. On the other hand, as shown in FIG. 8B, in a state where the pressure-bonding force of the beam member 16 to the column member 14 is weakened, the column member 14 and the beam member 16 are relatively movable, and the column member 14 The rigidity of the upper and lower layers of the joint portion 14A is reduced.

  With the above configuration, as shown in FIG. 9, by lowering the rigidity of the upper and lower layers of the beam member 16 that supports the floor slab on the second floor, the beam member 16 and the column member 14 that support the floor slab on the second floor. The rigidity of the layer of the structure 70 composed of As a result, by making the structure 70 longer than the dominant period of a large earthquake, the ground and the structure 70 that are vibrated by the large earthquake are suppressed from resonating.

  And by suppressing that the ground and the structure 70 which vibrate by a big earthquake resonate, the input energy to the structure 70 by a big earthquake reduces.

  Thus, by weakening the pressure-bonding force of a specific layer, the rigidity of the layer can be reduced, and a long period can be achieved by deforming the layer.

  Further, when a large earthquake occurs, the beam member 16 provided with the crimping force change device 76 and the column member 14 move relative to each other. Therefore, the beam member 16 provided with the crimping force change device 76 and the column member 14 are configured. Seismic energy can be effectively absorbed by the damping damper 78 provided in the layer of the structure 70.

  Moreover, it can suppress that another layer deform | transforms by concentrating a deformation | transformation to a specific layer according to the use of the structure 70. FIG.

  Moreover, since it is not necessary to provide the crimping force changing device 76 on all the tension members 74, it can be set as an inexpensive structure.

  Although the present invention has been described in detail with respect to specific embodiments, the present invention is not limited to such embodiments, and various other embodiments are possible within the scope of the present invention. It is clear to the contractor. For example, in the above embodiment, the crimping force changing device 76 is provided on the tension member 74 that crimps the beam member 16 on the second floor to the column member 14, but is not limited to the beam member 16 on the second floor. It may be a beam member 16 that supports a floor slab on the middle floor (see FIG. 10), or may be a beam member 16 that supports a floor slab on the 4th (top) floor (see FIG. 11). What is necessary is just to determine suitably according to the use of a thing.

  In this case, the vibration mode can be changed as shown in FIGS.

  Next, an example of a joint structure of a precast concrete member according to a third embodiment of the present invention and a structure including the joint structure of the precast concrete member will be described with reference to FIG.

  In addition, about the same member as 2nd Embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted.

  As shown in FIGS. 12A and 12B, the pressure-bonding force change device 86 provided in the joint structure 82 of the structure 80 has the beam member 16 that supports the floor slab (not shown) on the second floor as the column member 14. It is not provided in the tension member 84 that is provided on the tension member 84 to be crimped to the floor and supports the floor slabs of other floors. Furthermore, in the layer of the structure 80 composed of the beam member 16 and the column member 14 provided with the crimping force changing device 86 (in this embodiment, the layer provided between the first floor and the second floor) An oil damper 88 is provided as a vibration damping device that deforms and absorbs seismic energy.

  Specifically, a pair of brace members 90 are disposed from the first floor joint portion 14 </ b> A of the column member 14 so that the distal ends thereof are close to each other, and the distal ends of the pair of brace members 90 are joined by a joining member 92. It is joined. Further, the oil damper 88 described above is fixed to the beam member 16 on the second floor via the bracket 94, and the distal end portion of the movable rod 88 </ b> A of the oil damper 88 is fixed to the joining member 92.

  As shown in FIG. 12A, in the state where the pressure-bonding force of the beam member 16 to the column member 14 is increased, the rigidity of the upper and lower layers of the joint portion 14A on the second floor of the column member 14 is increased. On the other hand, as shown in FIG. 12 (B), in a state where the crimping force of the beam member 16 on the second floor is weakened against the column member 14, the column member 14 and the beam member 16 are relatively movable, The bending strength of the upper and lower layers of the joint portion 14A in the column member 14 is reduced.

  When a large earthquake occurs, the beam member 16 and the column member 14 provided with the crimping force change device 86 move relatively as shown in FIG. Thereby, the movable rod 88A of the oil damper 88 can move and can effectively absorb the seismic energy.

DESCRIPTION OF SYMBOLS 10 Structure 14 Column member 14A Joint part 16 Beam member 16A End surface 20 Tension member (crimping joining means)
28 Crimping force change device (crimping force changing means)
38 Junction Structure 50 Control Unit (Control Unit)
70 Structure 72 Bonding Structure 74 Tension Member (Pressure Bonding Means)
76 Crimping force change device (crimping force changing means)
78 Damping damper (damping device)
80 Structure 82 Joining structure 84 Tension member (crimping joining means)
86 Crimping force change device (crimping force changing means)
88 Oil damper (damping device)

Claims (3)

Column members made of precast concrete;
A pressure bonding means for pressure bonding the end face of the beam member made of precast concrete to the joint portion of the column member;
Pressure bonding force changing means for changing the pressure bonding force of the pressure bonding means;
Control means for controlling the pressure-bonding force changing means based on the P wave in the early stage of the earthquake to change the pressure-bonding force of the pressure-bonding means;
A joint structure of precast concrete members with The pressure bonding means is a tension member that penetrates the joint portion of the column member and is fixed to the beam members on both sides, and exerts a pressure bonding force by applying a tension force,
The crimping force changing means is provided on the specific tension member,
2. The precast concrete member according to claim 1, wherein a vibration damping device that deforms and absorbs seismic energy is provided in a layer of the structure including the beam member and the column member provided with the pressure changing unit. Junction structure.   The structure provided with the joining structure of the precast concrete member of Claim 1 or 2.

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