JP2009287172A - Method for constructing base-isolated building by inverted construction method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for constructing a base-isolated building by an inverted construction method, which dispenses with a jack for temporary support, despite the adoption of construction procedures of installation of a base-isolating device after the erection of a temporary steel column, and which enables the operation of installing the base-isolating device to be performed in a wide space with an opened upper section. <P>SOLUTION: When the base-isolated building, wherein a base-isolated layer is formed underground, is constructed by the inverted construction method, the temporary steel column 3 for directly transferring a load of an upper building frame, constructed above the base-isolated layer A, to a pile 2 is erected in a position not to interfere with the base-isolating device 4 which is installed in the base-isolated layer; the base-isolating device is installed on the top surface of a lower building frame 7a positioned directly below the base-isolated layer; subsequently, the upper building frame 7b, which is positioned directly above the base-isolated layer, is constructed while being supported on the temporary steel column; and after that, the temporary steel column is cut off in a part of the base-isolated layer, so that the upper skeleton constructed above the base-isolated layer is supported by the base-isolating device. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a method for constructing a base-isolated building in which a base-isolated layer is formed in the basement by a backlash method.

  A method for constructing a base-isolated building in which a base-isolated layer is formed in the basement by a back-strike method is already known from Patent Documents 1 to 5 and the like. The advantage of the back-striking method is that the vertical load of the first floor, which also serves as a support structure for mountain retaining works, is supported by the construction pillar, and the ground is excavated. It is to be done. However, in base-isolated buildings with base-isolated layers, seismic isolation devices such as laminated rubber are installed on the axis of the basement column, such as the column head, middle, column base, and foundation beam directly below the column base. Therefore, when adopting the reverse driving method, the position of the structural column that transmits the load of the upper frame of the seismic isolation layer to the pile (this is usually used as the basement column of the main building). And the position of the seismic isolation device will interfere.

  Therefore, in the prior art described in Patent Documents 1 and 2, after constructing the upper and lower housings that are located on both sides of the seismic isolation layer while being supported by the structural pillars, both sides of the structural pillar that penetrates the seismic isolation layer Install a seismic isolation device at the position of the excised construction column, with the jack removed from the seismic isolation layer, and the load on the upper housing was provisionally received by the jack. Later, construction procedures were taken, such as removing the jack and supporting the upper housing with a seismic isolation device.

  However, with this method, depending on the size of the building, a load of several thousand tons per pillar must be temporarily received with a jack. In addition, since an unbalanced load is generated in the entire frame, high accuracy is required for jack pressure / displacement management and housing stress / displacement management, making construction difficult. Moreover, in order to install the seismic isolation device with the load of the upper housing temporarily received by the jack, the seismic isolation device is inserted from the side into the gap between the upper and lower housings located above and below the seismic isolation layer. There is a need for cumbersome installation work in a narrow space whose upper part is restricted by the upper housing.

  In this respect, in the methods described in Patent Documents 3 and 4, a seismic isolation device is incorporated in advance in a part of the structural pillar, and the structural pillar is inserted to the head of the support pile and supported by the structural pillar. Since the underground part of the housing is constructed, there is no need for a temporary jack, and troublesome installation work in a small space such as installing a seismic isolation device in the gap between the upper and lower housings later It is unnecessary.

  However, with this method, there is a problem in the reliability of securing the performance of the seismic isolation device. In other words, in the reverse driving method, in general, after the construction of the retaining wall, the pile hole is excavated while injecting the hole wall stabilizing liquid into the ground, the rebar cage is inserted into the pile hole, and after the slime treatment, the underwater concrete is put through the tremy pipe. After placing the cast-in-place piles, the concrete pillars are inserted into the pile heads while the pile concrete has not yet solidified, and after the pile concrete has hardened, the surroundings of the concrete pillars are backfilled with earth and sand. , Primary excavation of the ground, construction of the first floor, secondary excavation, construction of the underground floor.

Therefore, if a seismic isolation device is built in a part of the structural pillar in advance, even if the seismic isolation device is cured with a sheet or the like so as to be insulated from the hole wall stabilizing liquid or backfill earth and sand, After inserting the built-in column into the pile hole in the presence of the hole wall stabilizing liquid and backfilling the surrounding area with earth and sand, the seismic isolation device will continue until the ground is actually excavated to expose the seismic isolation device. It is unknown what state it is in, and the possibility of adverse effects on the seismic isolation device due to infiltration and adhesion of hole wall stabilizer and backfilling earth cannot be denied. In addition, since loads are always applied to the seismic isolation device during the construction of the underground part and the ground part, unexpected deformation may occur in the seismic isolation apparatus due to the uneven load during construction.

  Therefore, the reliability of the seismic isolation device performance is low, and when actually constructed, as described in Patent Document 4, a seismic isolation layer was formed directly under the first floor and incorporated into the structural pillar. It seems necessary to install seismic isolation devices near the surface.

  In the method described in Patent Document 5, a hollow tubular portion that can accommodate the seismic isolation device is formed in a part of the structural pillar (a position where the seismic isolation device should be interposed), and the structural pillar is supported. After inserting the head of the pile and constructing the underground part of the frame while supporting it to the stem column, remove the lid attached to the side of the tubular part, and insert and install the seismic isolation device inside the tubular part However, after that, the tubular part around the seismic isolation device is excised and the upper housing is supported by the seismic isolation device, so that the seismic isolation device is cleared without contacting the hole wall stabilizing liquid or backfilling soil during the construction.

  However, in this method, since the seismic isolation device is inserted into the inside of the tubular portion from the opening on the side of the tubular portion, the seismic isolation device is installed in a narrow space where the top and bottom and the four sides are limited. The installation work is troublesome. In addition, the size of the seismic isolation device is limited by the inner diameter of the tubular portion, the size of the opening, etc., and it is actually adopted as the seismic isolation device that a sliding bearing having a larger outer dimension than the laminated rubber is adopted. It is impossible. In addition, the stress transmission between the tubular portion and the steel frame connected to the upper and lower sides of the tubular portion is not clear, and many reinforcing members are necessary for preventing the buckling of the tubular portion, and the seismic isolation device is capable of inserting these reinforcing members into the tubular portion. This is a size constraint.

Japanese Patent Laid-Open No. 10-18322 JP 2001-173269 A Japanese Patent Laid-Open No. 11-30053 JP 2000-291031 A Japanese Patent Laid-Open No. 10-280446

  The present invention has been made in consideration of the above points, and the purpose of the present invention is to construct a seismic pillar in the construction of a base-isolated building having a base-isolated layer formed underground by a reverse striking method. Rather than incorporating a seismic isolation device in advance, a jack for temporary support is not required, even though the construction procedure for installing the seismic isolation device is adopted after the construction of the structural pillar. It is another object of the present invention to provide a construction method that enables seismic isolation device installation work in a wide space open upward.

  The technical means taken by the present invention in order to achieve the above object are as follows. That is, the construction method of the base-isolated building by the reverse striking method according to the first aspect of the invention is constructed above the base-isolated layer in constructing the base-isolated building having the base-isolated layer formed by the reverse striking method. After installing the seismic isolation device in the seismic isolation layer, install the structural column that directly transmits the load of the upper frame to the pile to the position where it does not interfere with the seismic isolation device installed in the seismic isolation layer. The seismic isolation layer is excised and the upper frame constructed above the seismic isolation layer is supported by the seismic isolation device.

In the invention according to claim 1, in installing the seismic isolation device in the seismic isolation layer, after the upper and lower housings located opposite to each other above and below the seismic isolation layer are constructed, the seismic isolation device is seismically isolated. Although it is possible to adopt a construction procedure in which a layer is inserted and installed in the lateral direction, as in the invention according to claim 2, the seismic isolation device is provided on the upper surface of the lower casing located immediately below the seismic isolation layer. After the installation, the upper frame located immediately above the seismic isolation layer is constructed while being supported by the structural column, and then the structural column is excised at the seismic isolation layer and constructed above the seismic isolation layer. It is preferable to support the upper casing to be supported by the seismic isolation device for the reason described later.

  Invention of Claim 3 is the construction method of the seismic isolation building by the reverse driving method of Claim 1 or 2, Comprising: A plurality of construction pillars are arrange | positioned around an underground floor pillar, The lower end is embedded in a pile head of one pile.

  Invention of Claim 4 is the construction method of the seismic isolation building by the reverse driving method of Claim 3, Comprising: A structure pillar makes the part above a base isolation layer into a linear form, and is from a base isolation layer. It is characterized by being formed in a shape in which a lower part is bent inward.

  Invention of Claim 5 is the construction method of the base isolation building by the reverse driving method of Claim 3, Comprising: A structure pillar makes the part above a base isolation layer into a plurality of linear members, It is characterized in that it is formed in a shape in which the portion below the seismic isolation layer is bent inward and combined into one.

  Invention of Claim 6 is the construction method of the seismic isolation building by the reverse driving method of Claim 1 or 2, Comprising: The bottom of the straight member with a single structural pillar is above the base isolation layer In this case, the bifurcated bifurcated portion is bent outward and the lower end of the bifurcated portion is embedded in the pile head of one pile.

  According to the first aspect of the present invention, the construction procedure for installing the seismic isolation device after the construction of the structural pillar is adopted instead of incorporating the seismic isolation device in advance in a part of the structural pillar. However, after installing the seismic isolation column in the seismic isolation layer, install the seismic isolation column in the seismic isolation layer, install the seismic isolation column in the seismic isolation layer, and remove the upper frame. Since it is supported by a seismic isolation device, there is no need for a temporary jack.

  According to the second aspect of the present invention, in installing the seismic isolation device in the seismic isolation layer, the seismic isolation device is installed on the upper surface of the lower housing located directly under the seismic isolation layer, and then supported by the structural pillar. However, since the upper frame located directly above the seismic isolation layer is constructed, the seismic isolation device installation work for the seismic isolation layer will be performed in a wide space that is not restricted by the upper frame. There is an effect that the work is easy.

  According to the invention described in claim 3, since the lower end portion is embedded in the pile head of one pile regardless of arranging a plurality of structural pillars around the underground floor pillar, the number of piles is Less cost and economy.

  According to the invention described in claim 4, since the structural pillar is formed in a shape in which a portion above the seismic isolation layer is linear and a portion below the seismic isolation layer is bent inward, the pile Even if the diameter is not increased or the pile head is not enlarged, the lower end can be embedded in the pile head of one pile, which is economical.

  According to the invention described in claim 5, the structural pillar is joined to one by bending a portion above the seismic isolation layer into a plurality of linear members and bending a portion below the seismic isolation layer inward. Since it is formed in a shape, the lower end can be embedded in the pile head of one pile without increasing the pile diameter or expanding the pile head, which is economical. Moreover, since the lower part is combined into one even though the part above the seismic isolation layer is arranged as a plurality of linear members and arranged around the basement column, the pile head Insertion into the part can be done at once, and the construction of the structural pillar can be done in a short time.

According to the sixth aspect of the present invention, the bifurcated bifurcated portion has a bifurcated portion in which the stem column is bifurcated by bending the lower end side of one linear member outward above the seismic isolation layer. In addition to the effect of the invention according to claim 1 or 2, among the construction pillars, the construction pillars above the seismic isolation layer are permanently installed. It can be used as an underground floor pillar and is economical.

  Hereinafter, an embodiment of a method for constructing a base-isolated building by a reverse driving method according to the present invention will be described with reference to the drawings. First, as shown in FIG. 1, after constructing the retaining wall 1, excavating a predetermined position of the ground, constructing a cast-in-place pile 2 in which the pile head is enlarged, and while the pile concrete is not yet solidified, In other words, to the position where the two structural pillars 3 per cast-in-place pile 2 do not interfere with the seismic isolation device 4 installed in the seismic isolation layer A described later (see FIG. 12), After the pile concrete is hardened to some extent, it is backfilled with earth and sand 5 after the pile concrete is hardened to some extent. Since the pile head of the cast-in-place pile 2 is enlarged, even if the two structural pillars 3 are arranged at positions where they do not interfere with the seismic isolation device 4, as shown in FIG. 3 can be embedded in the pile head of one cast-in-place pile 2.

After that, following the construction procedure of a general reverse driving method, primary excavation of the ground is performed, and as shown in FIG. to, secondary drilling, to build the underground floor B _1. 6 is a permanent underground floor pillar that is handed down from the upper floor to the lower floor, and is a steel-framed reinforced concrete structure.

And if it excavates to the last excavation bottom, as shown in Drawing 4 and Drawing 7, it constructs pressure-resistant panel 8 as lower frame 7a located directly under seismic isolation layer A, and underground outer wall 9 along mountain retaining wall 1, The seismic isolation device 4 is attached to the upper surface of the lower housing (pressure platen 8) 7a so as to be concentric with the axis of the basement column 6. The installation work of the seismic isolation device 4 with respect to the seismic isolation layer A is performed as shown in FIG. 7 by an upper frame located directly above the seismic isolation layer A (this is constructed above the seismic isolation layer A). It is part of the upper skeleton, composed of pedestal like underground Kaibashira 6 of this setting the lowermost floor B _2.) 7b is made before it is built. Reference numeral 3a shown in FIG. 7 is a shear connector provided on the construction pillar 3 as necessary.

  Next, as shown in FIG. 8, an upper housing 7b located immediately above the seismic isolation layer A is supported while being supported by the structural pillar 3, and the upper end side of the seismic isolation device 4 is connected to the upper housing 7b. As shown in FIGS. 5 and 9, the column base of the basement column 6 is integrated with the column portion above it.

  After that, as shown in FIG. 10, the structural pillar 3 is cut off at the part of the seismic isolation layer A, and the upper housing constructed above the seismic isolation layer A is supported by the seismic isolation device 4, and FIG. As shown in the figure, the true pillar portion above the seismic isolation layer A is cut out, and as shown in FIG. 6, a base-isolated building having the base isolation layer A in the basement is constructed. Depending on the interior finish of the underground floor pillar 6, the construction pillar part above the seismic isolation layer A may be left.

  According to the above configuration, the seismic isolation device 4 is not built in a part of the structural pillar 3 in advance, but the construction procedure for installing the seismic isolation device 4 after the construction of the structural pillar 3 is adopted. In spite of this, it is not necessary to have a temporary jack, and the seismic isolation device can be installed in a wide space with the top open.

  That is, after the structural column 3 is installed at a position where it does not interfere with the seismic isolation device 4 and the seismic isolation device 4 is installed in the lower casing 7a immediately below the seismic isolation layer A, the structural column 3 is installed at the seismic isolation layer A portion. Since the upper frame constructed above the seismic isolation layer A is supported by the seismic isolation device 4, a jack for provisional reception is unnecessary.

In particular, after the seismic isolation device 4 is installed on the upper surface of the lower housing 7a, the upper housing 7b positioned immediately above the seismic isolation layer A is constructed while being supported by the structural pillar 3, so that the seismic isolation device 4 is installed. Is performed in a wide space where the upper part is not limited by the upper housing 7b, and the installation work of the seismic isolation device 4 is easy.

  FIG. 13 shows another embodiment of the present invention. This embodiment is characterized in that a beam steel frame 10 is installed between two structural pillars 3 to reinforce the true pillars 3 and to handle the two structural pillars 3 as a single unit. is there. The beam steel frame 10 is provided in the middle of the floor height and is excised before the construction of the basement column. Other configurations and operations are the same as those of the embodiment of FIGS.

  14 and 15 show another embodiment of the present invention. In this embodiment, the upper part of the seismic isolation layer A is linear, and the erected column 3 having a shape in which the lower part of the seismic isolation layer A is bent inward is equally spaced around the four underground floor pillars 6. There is a feature in the point arranged in.

  According to this structure, since the part below the seismic isolation layer A of the structural pillar 3 is bent inward, it is not necessary to enlarge the pile head of the cast-in-place pile 2 or increase the pile diameter. The lower ends of the four structural pillars 3 can be embedded in the pile head of one cast-in-place pile 2.

  In the example shown in the figure, the straight portions of the four structural pillars 3 are connected by a beam steel frame 10 arranged in an annular shape to reinforce the structural pillar 3 and integrate the four structural pillars 3 together. The cast-in-place pile 2 can be inserted into the pile head at one time. However, the beam steel frame 10 may be omitted, and four independent structural pillars 3 may be implemented. In addition, when the four structural pillars 3 are integrated by connecting with the beam steel frame 10, the beam steel frame 10 is arranged in an annular shape as shown in the figure, so that the beam steel frame 10 can be used for the construction of the underground floor column 6 or the exemption. It is possible to prevent the seismic device 4 from becoming an obstacle to the installation work. Other configurations and operations are the same as those of the embodiment of FIGS.

  FIG. 16 shows another embodiment of the present invention. In this embodiment, the structural pillar 3 is formed in a shape in which a portion above the seismic isolation layer A is formed as two linear members and a portion below the seismic isolation layer A is bent inward to be combined into one. It is characterized in that it is.

  According to this configuration, the lower end can be embedded in the pile head of one pile without increasing the pile diameter or expanding the pile head, which is economical. Moreover, since the upper part of the seismic isolation layer A is two linear members and the two lower ends are combined around the basement column 6, the lower end part is connected to one. The pile head can be inserted at a time, and the construction pillar 3 can be built in a short time.

  In addition, as shown by a virtual line in FIG. 16, the beam steel frame 10 is installed on a linear member above the seismic isolation layer A at an appropriate height position to reinforce the frame column 3, and the first floor F After construction, the beam steel frame 10 may be excised.

  17 to 20 show another embodiment of the present invention. In this embodiment, the structure pillar 3 is formed into a bifurcated shape by bending the lower end side of one linear member 3A outwardly above the seismic isolation layer A, and bifurcated bifurcated portions 3B, 3B. Is characterized in that the lower end of is embedded in the pile head of one cast-in-place pile 2.

More specifically, as shown in FIG. 18, the basement floor B <b> 1 is constructed by the reverse driving method, and after the construction of the pressure platen 8 as the lower housing 7 a located immediately below the seismic isolation layer A, the lower housing ( The seismic isolation device 4 is installed concentrically with the axis of the basement column 6 on the upper surface of the pressure platen 8) 7a. As shown in phantom lines in FIG. 18, the seismic isolation device 4 is installed in an upper casing located directly above the seismic isolation layer A (this is a part of the upper casing constructed above the seismic isolation layer A). It is performed before the construction of the lower floor B2 and the base of the underground basement column 6), so that the upper part is not restricted by the upper housing 7b and is seismically isolated. The installation work of the device 4 is easy.

  Next, as shown in FIG. 19, an upper frame 7b is constructed which is positioned directly above the seismic isolation layer A while being supported by the structural pillar 3, and the column base of the basement column 6 is integrated with the column portion above it. Let

  After that, as shown in FIG. 20, the structural pillar 3 is cut off at the part of the seismic isolation layer A, and the upper housing constructed above the seismic isolation layer A is supported by the seismic isolation device 4 and shown in FIG. A base-isolated building in which the base isolation layer A is formed in the basement is constructed.

  According to the above configuration, the construction pillar 3 has a bifurcated shape by bending the lower end side of one linear member 3A outwardly above the seismic isolation layer A, and bifurcated into a bifurcated portion 3B. Since the lower end of 3B is embedded in the pile head of one cast-in-place pile 2, the built-up column above the seismic isolation layer A of the built-up column 3 is used as the main basement column 6. Can be economical. Other configurations and operations are the same as those of the embodiment of FIGS.

  In each of the above-described embodiments, the seismic isolation layer A is formed between the lowest floor B2 and the pressure platen 8, but it is formed on any of the head of the basement column 6, the middle, or the column base. Also good. Moreover, although laminated rubber was illustrated as the seismic isolation device 4, you may implement using another type of seismic isolation device 4 with a larger external dimension than laminated rubber, such as a sliding bearing. Instead of the cast-in-place pile 2, an RC continuous wall pile or a soil cement pile may be used. The pile is not limited to the case where one pile is arranged on one pillar, but can be implemented as long as the pile can transmit the load of the true pillar through the footing, and can be an off-the-shelf pile such as multiple PHC piles. May be. Furthermore, in Claims 1 and 2, the seismic isolation building is not limited to the pile foundation but may be a direct foundation. In that case, the structural column is supported by a temporary short pile (temporary structural column).

It is the schematic longitudinal cross-sectional view which illustrated the embodiment of this invention and constructed | assembled the retaining wall and the construction pillar. It is the schematic longitudinal cross-sectional view which constructed | assembled the 1st floor. It is the schematic longitudinal cross-sectional view which constructed | assembled the underground floor B1. It is the schematic longitudinal cross-sectional view which installed the seismic isolation apparatus. It is the schematic longitudinal cross-sectional view which constructed | assembled the upper frame of the seismic isolation layer upper part. It is a schematic longitudinal cross-sectional view of the constructed seismic isolation building. It is a longitudinal cross-sectional view of the principal part which installed the seismic isolation apparatus. It is the longitudinal cross-sectional view of the principal part which constructed the upper frame of the seismic isolation layer upper part. It is a longitudinal cross-sectional view of the principal part which integrated the column base of the underground floor column provided in the upper housing with the upper column part. It is a longitudinal cross-sectional view of the principal part which excised the structure pillar in the part of the seismic isolation layer. It is a longitudinal cross-sectional view of the principal part of the constructed seismic isolation building. It is a top view of the principal part which shows the positional relationship of a structural pillar and a seismic isolation apparatus. It is a top view of the principal part which shows other embodiment of this invention. It is a top view of the principal part which shows other embodiment of this invention. It is a longitudinal cross-sectional view of the principal part which shows other embodiment of this invention. It is a longitudinal cross-sectional view of the principal part which shows other embodiment of this invention. It is a schematic longitudinal cross-sectional view of the constructed seismic isolation building which shows other embodiment of this invention. It is a longitudinal cross-sectional view of the principal part which installed the seismic isolation apparatus. It is the longitudinal cross-sectional view of the principal part which constructed | assembled the upper frame of the seismic isolation layer upper part, and integrated the column base of the basement column with the upper column part. It is a longitudinal cross-sectional view of the principal part which excised the structure pillar in the part of the seismic isolation layer.

Explanation of symbols

A Seismic isolation layer B ₁ Basement floor B ₂ Bottom floor F 1st floor 1 Mountain retaining wall 2 Cast-in-place pile 3 Construction pillar 3A One linear member 3B Two-pronged part 3a Shear connector 4 Seismic isolation device 5 Earth and sand 6 Basement floor pillar 7a Lower housing 7b Upper housing 8 Pressure-resistant panel 9 Underground wall 10 Beam steel

Claims (6)

  When constructing a base-isolated building with a base-isolated layer in the basement by the back-strike method, a structural column that directly transmits the load of the upper frame constructed above the base-isolated layer to the pile is installed in the base-isolated layer. After installing the seismic isolation device in the seismic isolation layer, excise the structural column at the seismic isolation layer and remove the upper frame constructed above the seismic isolation layer. A method of constructing a base-isolated building by the backlash method, which is supported by a base-isolated device.   After installing the seismic isolation device on the upper surface of the lower frame located directly below the seismic isolation layer, construct the upper frame located directly above the seismic isolation layer while supporting the structural column, and then exempt the structural column. 2. The method for constructing a base-isolated building by a backlash construction method according to claim 1, wherein the seismic layer is excised and the upper frame constructed above the base-isolated layer is supported by a base-isolating device.   3. The reverse driving method according to claim 1, wherein a plurality of structural pillars are arranged around the underground floor pillar, and a lower end portion of the structural pillar is embedded in a pile head of one pile. How to build a base-isolated building.   4. The reverse driving method according to claim 3, wherein the structural column is formed in a shape in which a portion above the base isolation layer is linear and a portion below the base isolation layer is bent inward. How to build a base-isolated building.   The true column is formed in a shape in which a portion above the seismic isolation layer is formed as a plurality of linear members, and a portion below the seismic isolation layer is bent inward to be combined into one. The construction method of the seismic isolation building by the reverse driving method of Claim 3.   The straight pillar has a bifurcated shape with the lower end of one linear member bent outwardly above the seismic isolation layer, and the lower end of the bifurcated portion is a pile head of one pile. The method for constructing a base-isolated building by the reverse driving method according to claim 1, wherein the building is embedded in a part.

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