JP2017071955A - Construction method for structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a construction method for a structure, which can reduce stress generated in an upper structure, in association with settlement of a high-rise part side of the upper structure with respect to a low-rise part side thereof.SOLUTION: In a construction method for a structure 10, an upper structure 30, which comprises a low-rise part 30L and a high-rise part 30H joined to the low-rise part 30L and higher than the low-rise part 30L, is constructed on a lower structure 20. A hydraulic jack for supporting the low-rise part 30L on a footing slab 22 is lowered as construction of the high-rise part 30H supported by the footing slab 22 of the lower structure 20 progresses.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a construction method for a structure.

  There is a connecting member that connects the foundations of the low-rise structure and the high-rise structure attached together so that they can be displaced relative to each other in the vertical direction, and sinks the foundation of the high-rise structure to the foundation of the low-rise structure (for example, natural settlement) (for example, , See Patent Document 1).

  Moreover, it is the construction method of the upper structure which has the low layer part and high layer part from which height differs, Comprising: A slit is formed in the foundation beam over a low layer part and a high layer part, and a high part part is compared with the low layer part side of a foundation beam After sinking the side, there is a method in which concrete is post-placed into the slit to connect the foundation beam (for example, see Patent Document 2).

JP 2011-140758 A JP-A-8-27809

  By the way, when constructing an upper structure having a low layer portion and a high layer portion, the high layer portion side may sink with respect to the low layer portion side of the upper structure as the construction of the high layer portion proceeds. In this case, stress (bending stress) is generated at the boundary between the low layer portion and the high layer portion in the upper structure, and the boundary portion may be damaged.

  An object of the present invention is to reduce the stress generated in the upper structure as the upper layer sinks with respect to the lower layer of the upper structure in consideration of the above fact.

  The construction method according to claim 1, wherein the upper structure having a low layer portion and a high layer portion joined to the low layer portion and having a height higher than the low layer portion is provided on the lower structure. In the construction method of the structure to be constructed, the jack that supports the low-layer part is lowered with respect to the lower structure as the construction of the high-layer part supported by the lower structure proceeds.

  According to the construction method of the structure according to the first aspect, the upper structure having the low layer portion and the high layer portion is constructed on the lower structure. At this time, as the construction of the high-rise portion proceeds, the high-rise portion side may sink with respect to the low-rise portion side of the upper structure. In this case, stress (bending stress) is generated at the boundary between the low layer portion and the high layer portion in the upper structure, and the boundary portion may be damaged.

  As a countermeasure against this, in the present invention, as the construction of the high layer portion supported by the lower structure proceeds, the jack that supports the lower layer portion is lowered relative to the lower structure (jack down). Thereby, the amount of settlement on the lower layer side of the upper structure can be matched with the amount of settlement on the higher layer side. In other words, by lowering the jack that supports the lower layer portion with respect to the lower structure, the amount of subsidence on the higher layer side relative to the lower layer side of the upper structure can be reduced. Therefore, the stress which generate | occur | produces in the boundary part of the low layer part and high layer part in an upper structure can be reduced.

  The structure construction method according to claim 2 is the structure construction method according to claim 1, wherein the lower structure is a boundary portion between the low-layer portion side and the high-layer portion side in plan view. The upper structure extends in a plan view across the lower striking band and extends between the lower layer portion and the higher layer portion, and the lower layer portion side is supported by the jack. The jack is lowered when the amount of subsidence on the high-layer part side with respect to the low-layer part side of the horizontal member becomes a predetermined value or more.

  According to the construction method of the structure according to the second aspect, the lower structure has the trailing zone extending along the boundary portion between the low layer portion side and the high layer portion side in plan view. In this case, as the construction of the high-rise portion proceeds, the high-rise portion side sinks with respect to the low-rise portion side of the lower structure with the trailing zone as a boundary. At this time, the deformation (bending stress) generated at the boundary between the lower layer portion side and the higher layer portion side in the lower structure is reduced by the deformation or the like of the trailing band.

  On the other hand, the upper structure has a horizontal member that extends across the lower band and the higher layer in a plan view. In this case, as the construction of the high-rise portion proceeds, the high-rise portion side sinks with respect to the low-rise portion side of the horizontal member. Moreover, the high-rise part side of a horizontal member is supported by the high-rise part side of a lower structure. As described above, the lower layer side of the lower structure sinks with respect to the lower layer side of the lower structure as the construction of the higher layer proceeds. Therefore, the amount of settlement on the high-rise part side of the horizontal member increases in accordance with the amount of settlement on the high-rise part side of the lower structure. Therefore, the amount of subsidence of the high layer portion relative to the low layer portion of the horizontal member increases, and the stress generated at the boundary between the low layer portion side and the high layer portion side of the horizontal member may be excessive.

  As a countermeasure against this, in the present invention, when the amount of subsidence on the high-layer part side with respect to the low-layer part side of the horizontal member becomes a predetermined value or more, the jack that supports the low-layer part side of the horizontal member with respect to the lower structure is lowered. Thereby, the amount of settlement on the lower layer side of the horizontal member can be matched with the amount of settlement on the higher layer side. Therefore, the stress which generate | occur | produces in the boundary part of the low layer part and high layer part in a horizontal member is reduced.

  As described above, according to the present invention, it is possible to reduce the stress generated at the boundary between the low layer portion side and the high layer portion side in the horizontal member while reducing the stress generated in the lower structure by the trailing band.

  The method for constructing a structure according to claim 3 is the method for constructing a structure according to claim 1 or 2, wherein the lower layer portion and the lower structure are placed on the lower layer portion before the jack is lowered. After joining the upper part of the seismic isolation device arranged between and lowering the jack, concrete is placed under the seismic isolation device to join the lower part of the seismic isolation device to the lower structure.

  According to the structure construction method of the third aspect, before lowering the jack that supports the lower layer portion of the upper structure, the upper portion of the seismic isolation device is joined to the lower layer portion. Next, as the construction of the high layer portion of the upper structure proceeds, the jack that supports the low layer portion with respect to the lower structure is lowered. Thereby, the amount of settlement on the lower layer side of the upper structure can be matched with the amount of settlement on the higher layer side. Thereafter, concrete is placed under the seismic isolation device, and the lower part of the seismic isolation device is joined to the lower structure. Accordingly, the lower layer portion of the upper structure is supported by the lower structure via the seismic isolation device.

  As described above, in the present invention, the upper part of the seismic isolation device is joined in advance to the lower layer portion of the upper structure, the jack supporting the lower layer portion is lowered, and then concrete is placed under the seismic isolation device (rear) The lower part of the seismic isolation device is joined to the lower structure. Therefore, the trouble of post-construction of the seismic isolation device is reduced.

  Furthermore, in the present invention, since concrete is placed (post-placed) under the seismic isolation device, the concrete post-working work is performed in comparison with the case where concrete is placed (post-placed) on the base isolation device. It becomes easy. Therefore, the trouble of post-construction of the seismic isolation device is further reduced.

  As described above, according to the construction method for a structure according to the present invention, it is possible to reduce the stress generated in the upper structure as the upper structure sinks with respect to the lower structure of the upper structure.

1. It is the 1-1 sectional view taken on the line of FIG. 2 which shows the state in the middle of construction of the structure constructed | assembled by the construction method of the structure which concerns on one Embodiment. It is a top view of the structure shown by FIG. (A) And (B) is the elements on larger scale of FIG. 1 explaining the construction method of the low-rise side seismic isolation layer shown by FIG. (A) And (B) is the elements on larger scale of FIG. 1 explaining the construction method of the low-rise side seismic isolation layer shown by FIG. (A) And (B) is the elements on larger scale of FIG. 1 explaining the construction method of the structure shown by FIG. (A) And (B) is the elements on larger scale of FIG. 1 explaining the construction method of the structure shown by FIG. It is an enlarged view corresponding to Drawing 4 (B) showing the modification of the construction method of the structure concerning one embodiment.

  Hereinafter, a construction method for a structure according to an embodiment of the present invention will be described with reference to the drawings.

  First, the structure of the structure 10 constructed by the construction method according to the present embodiment will be described. FIG. 1 shows a structure 10 during construction. The structure 10 includes a lower structure 20 and an upper structure 30 constructed on the lower structure 20.

  The upper structure 30 has a low layer portion 30L and a high layer portion 30H. The low layer portion 30L and the high layer portion 30H are joined together and integrated. The low layer portion 30L and the high layer portion 30H are supported by the lower structure 20. Further, the height E1 of the high layer portion 30H is higher than the height E2 of the low layer portion 30L (E1> E2). As a result, the weight of the high layer part 30H is made larger than the weight of the low layer part 30L.

  Here, the height E1 of the high layer portion 30H is, for example, the length from the support surface 22A of the lower structure 20 that supports the high layer portion 30H to the upper end of the high layer portion 30H. Similarly, the height E2 of the low layer portion 30L is, for example, the length from the support surface 22A of the lower structure 20 that supports the low layer portion 30L to the upper end of the low layer portion 30L.

  As shown in FIG. 2, the low layer portion 30 </ b> L is disposed on the outer periphery of the upper structure 30 in plan view. The low layer portion 30 </ b> L is formed in a rectangular frame shape in plan view, and surrounds the high layer portion 30 </ b> H disposed in the central portion of the upper structure 30.

  The upper structure 30 is provided with a foundation beam 32. The foundation beam 32 extends across the lower end portion of the low layer portion 30L and the lower end portion of the high layer portion 30H, and is disposed across the rear striking band 26 described later in plan view. The foundation beam 32 is made of reinforced concrete, for example, and is supported by the lower structure 20 via a plurality of seismic isolation devices 42.

  FIG. 2 shows only the foundation beam 32 that crosses the central portion of the high-rise part 30 </ b> H in plan view among the plurality of foundation beams 32. The foundation beam 32 is an example of a horizontal member (horizontal structural member) that constitutes a part of the lower layer portion 30L and the higher layer portion 30H. Furthermore, the foundation beam 32 is not limited to a reinforced concrete structure, and may be a steel structure or the like.

  As shown in FIG. 1, the lower structure 20 is a base portion of the structure 10. The lower structure 20 is, for example, a direct foundation, and includes a foundation slab 22 and a retaining wall 24 raised from the outer periphery of the foundation slab 22. In addition, the lower structure 20 is not limited to a direct foundation, but may be another basic form.

  The foundation slab 22 is made of reinforced concrete, and is provided along the bottom of the excavated ground 12. The upper surface of the foundation slab 22 is a support surface 22A that supports the low layer portion 30L and the high layer portion 30H of the upper structure 30 respectively. The basic slab 22 has a low-layer support portion 22L that supports the low-layer portion 30L and a high-layer support portion 22H that supports the high-layer portion 30H.

  A base isolation layer 40 is formed between the foundation slab 22 and the upper structure 30. In the seismic isolation layer 40, a plurality of seismic isolation devices 42 are arranged in two horizontal directions. The seismic isolation device 42 is, for example, a laminated rubber bearing. These seismic isolation devices 42 are installed on the support surface 22A of the foundation slab 22, and support the low-rise part 30L and the high-rise part 30H of the upper structure 30.

  More specifically, as shown in FIG. 6B, the seismic isolation device 42 includes an apparatus main body 44, a lower base plate 46 provided at the lower end of the apparatus main body 44, and an upper end of the apparatus main body 44. The upper base plate 48 is provided.

  The lower base plate 46 is joined to the support surface 22 </ b> A of the foundation slab 22 via the lower footing 50. On the other hand, the upper base plate 48 is joined to the lower surface of the foundation beam 32 of the upper structure 30 via the upper footing 52. Thereby, the foundation beam 32 is supported by the support surface 22 </ b> A of the foundation slab 22 via the plurality of seismic isolation devices 42.

  In the following, for convenience of explanation, the base isolation device 42 that supports the lower layer portion 30L side portion of the foundation beam 32 (hereinafter referred to as “low layer side portion”) 32L is referred to as the lower layer seismic isolation device 42L. The seismic isolation device 42 that supports the part 32H on the high-rise part 30H side (hereinafter referred to as “higher part”) is referred to as a high-rise seismic isolation device 42H.

  3B, the lower base plate 46 is provided with an anchor 54 embedded in the lower footing 50, and the upper base plate 48 has an anchor 56 embedded in the upper footing 52. As shown in FIG. Is provided.

As shown in FIG. 5A, the foundation slab 22 is formed with a trailing band 26 such as a construction joint, for example. The trailing band 26 is formed in a groove shape on the support surface 22 </ b> A of the foundation slab 22, and the slab thickness t is thinner than the slab thickness T of other parts of the foundation slab 22. As a result, the trailing band 26 is more easily deformed than other portions of the foundation slab 22.
In addition, the slab thickness t of the trailing band 26 can be changed as appropriate. Further, the slab thickness t can be made zero, and the low-layer support part 22L and the high-layer support part 22H can be separated.

  Further, as shown in FIG. 2, the trailing band 26 has a rectangular frame shape extending along a boundary portion 22R (see FIG. 6B) between the low layer portion 30L side and the high layer portion 30H side in a plan view. Is formed. As a result, the high-rise support portion 22H easily sinks with respect to the low-rise support portion 22L with the trailing band 26 as a boundary.

  As shown in FIG. 6B, concrete (post-cast concrete) 28 is placed (post-cast) on the post-cast belt 26. More specifically, the concrete 28 is placed in the post-casting band 26 after the high-rise support portion 22H is submerged with respect to the low-rise support portion 22L of the foundation slab 22. Thereby, the low-layer support part 22L and the high-layer support part 22H of the foundation slab 22 are joined.

  Note that the boundary portion 22R between the lower layer portion 30L side and the higher layer portion 30H side in the basic slab 22 referred to here is a low layer side seismic isolation device 42L (low layer side support member) and a high layer side seismic isolation device 42H (high layer). It means the part between the side support member).

  Next, an example of the construction method of the structure concerning this embodiment is demonstrated.

  First, the lower structure 20 is constructed in the lower structure construction step. Specifically, concrete is placed on the bottom of the excavated ground 12 to construct the foundation slab 22 and the retaining wall 24. At this time, the upper surface (support surface 22A) of the basic slab 22 is along a boundary portion 22R (see FIG. 6B) between the lower layer portion 30L side and the higher layer portion 30H side of the upper structure 30 in plan view. A groove-shaped back band 26 is formed.

  Next, in the seismic isolation device installation step, the lower layer side seismic isolation device 42L is installed on the lower layer support portion 22L of the foundation slab 22, and the higher layer side seismic isolation device 42H is installed on the upper layer support portion 22H of the foundation slab 22. At this time, for example, the low-rise seismic isolation device 42L is installed on the support surface 22A of the foundation slab 22 via the temporary support base 60 as shown in FIG.

  In addition, a formwork 62 for the lower footing 50 is temporarily installed along the outer peripheral portion of the lower base plate 46 of the lower layer side seismic isolation device 42L. The lower footing 50 of the low-rise seismic isolation device 42L is formed by post-construction as will be described later. Further, a mold 64 for the upper footing 52 is temporarily installed along the outer peripheral portion of the upper base plate 48. The upper footing 52 of the lower layer side seismic isolation device 42L is constructed integrally with the foundation beam 32 in the foundation beam construction process described later.

  Similar to the low-rise side seismic isolation device 42L, the high-rise side seismic isolation device 42H is installed on the support surface 22A of the foundation slab 22 via a temporary cradle. Further, a mold 62 for the lower footing 50 is temporarily installed along the outer peripheral portion of the lower base plate 46 of the high-rise seismic isolation device 42H. Then, concrete is placed in the mold 62 to form the lower footing 50. Accordingly, the lower portion of the high-rise seismic isolation device 42 </ b> H and the support surface 22 </ b> A of the foundation slab 22 are joined via the lower footing 50.

  In addition, a mold 64 for the upper footing 52 is temporarily installed along the outer periphery of the upper base plate 48 of the high-rise seismic isolation device 42H. The upper footing 52 of the high-rise seismic isolation device 42H is constructed integrally with the foundation beam 32 in a foundation beam construction process described later.

  Next, in the foundation beam construction step (horizontal member construction step), as shown in FIG. 3 (B), a plurality of supporters 66 are set on the support surface 22A of the foundation slab 22, and the foundation beam 32 is formed thereon. The formwork 68 is temporarily installed. The foundation beam 32 is constructed by placing concrete in the mold 68. At this time, concrete is also placed in the mold 64 for the upper footing 52 of the low-rise side seismic isolation device 42L and the high-rise side seismic isolation device 42H to form the upper footing 52. Thereby, each low-rise side seismic isolation device 42L and high-rise side seismic isolation device 42H are joined to the lower surface of the foundation beam 32 via the upper footing 52, respectively.

  Next, as shown in FIG. 4A, the temporary support base 60 that supports the low-rise seismic isolation device 42L is disassembled and removed. Thereby, the lower layer side seismic isolation device 42L is supported in a state of being suspended from the foundation beam 32. Next, as shown in FIG. 4B, a hydraulic jack 70 as an example of a jack is installed around the low-rise seismic isolation device 42 </ b> L, and the foundation beam 32 is supported with respect to the foundation slab 22. In addition, a giraffe jack 72 for horizontally adjusting the foundation beam 32 is installed around the low-rise seismic isolation device 42L. In the present embodiment, the support 66, the hydraulic jack 70, and the giraffe jack 72 are appropriately replaced.

  Next, as shown in FIG. 5 (A), the amount of subsidence of the foundation beam 32 is measured on the lower surface of the foundation beam 32 located above the adjacent lower layer side seismic isolation device 42L and upper layer side seismic isolation device 42H. A pair of displacement sensors 80 are respectively installed. The pair of displacement sensors 80 need only be able to measure the amount of settlement of the high-layer side portion 32H with respect to the low-layer side portion 32L of the foundation beam 32, and the installation positions thereof can be changed as appropriate.

  Next, in the upper structure construction process, the low layer portion 30L and the high layer portion 30H are sequentially constructed on the foundation beam 32. Here, as shown in FIG. 1, the height E1 of the high layer portion 30H is set higher than the height E2 of the low layer portion 30L. Therefore, as shown by the two-dot chain line, as the construction of the high layer portion 30H progresses and the height E1 increases, the basic slab with the trailing band 26 as a boundary due to the weight difference between the low layer portion 30L and the high layer portion 30H. The high-rise support portion 22H sinks with respect to the 22 low-rise support portions 22L, and the high-rise portion 32H sinks with respect to the low-rise portion 32L of the foundation beam 32.

  More specifically, as indicated by an arrow a in FIG. 5B, the high-rise support portion 22H sinks with respect to the low-rise support portion 22L of the foundation slab 22 with the trailing zone 26 as a boundary. At this time, the deformation or breakage of the trailing band 26 reduces the stress generated between the low-layer support portion 22L and the high-layer support portion 22H in the foundation slab 22.

  Further, as the high-layer support portion 22H sinks with respect to the low-layer support portion 22L of the foundation slab 22, the high-layer side portion 32H sinks with respect to the low-layer side portion 32L of the foundation beam 32 as indicated by an arrow b. As a result, the stress generated at the boundary between the lower layer portion 32L and the higher layer portion 32H of the foundation beam 32 may be excessive.

  As a countermeasure, in this embodiment, the pair of displacement sensors 80 is used to construct the high layer portion 30H while measuring the amount of settlement S of the high layer side portion 32H with respect to the low layer side portion 32L of the foundation beam 32. Then, when the subsidence amount S of the high-layer side portion 32H with respect to the low-layer side portion 32L of the foundation beam 32 becomes a predetermined value or more, as shown in FIG. 6A, the low-layer side portion 32L of the foundation beam 32 is supported. The hydraulic jack 70 to be lowered is lowered (jack down), and the amount of settlement of the lower layer side portion 32L of the foundation beam 32 is adjusted to the amount of settlement of the higher layer side portion 32H as indicated by an arrow c. As a result, the stress generated at the boundary between the lower layer portion 32L and the higher layer portion 32H in the foundation beam 32 is reduced.

  In addition, the predetermined value of the subsidence amount S of the high-layer side portion 32H with respect to the low-layer side portion 32L of the foundation beam 32 is appropriately set based on the bending rigidity and bending strength of the foundation beam 32.

  Next, the high layer portion 30H of the upper structure 30 is further constructed while measuring the sinking amount S of the high layer side portion 32H with respect to the low layer side portion 32L of the foundation beam 32 by the pair of displacement sensors 80. Then, when the subsidence amount S of the high-layer side portion 32H with respect to the low-layer side portion 32L of the foundation beam 32 again becomes a predetermined value or more, the hydraulic jack 70 that supports the low-layer side portion 32L of the foundation beam 32 is provided as described above. The amount of settlement of the lower layer side portion 32L of the foundation beam 32 is adjusted to the amount of settlement of the higher layer side portion 32H. As a result, the stress generated at the boundary between the lower layer side portion 32L side and the higher layer side portion 32H side in the foundation beam 32 is reduced.

  In this way, the upper layer 30H of the upper structure 30 is constructed while jacking down the hydraulic jack 70 as appropriate. And if the high-rise part 30H reaches the predetermined floor or more, the following construction is performed in parallel with the construction of the remaining floor of the high-rise part 30H.

  That is, the foundation beam 32 is adjusted horizontally by the giraffe jack 72. Then, concrete is placed in a formwork 62 temporarily provided around the low-rise side seismic isolation device 42 </ b> L to form the lower footing 50. Thereby, as shown in FIG. 6B, the lower part of the low-rise seismic isolation device 42 </ b> L is joined to the support surface 22 </ b> A of the foundation beam 32. Further, the pair of displacement sensors 80 is also removed as appropriate.

  Furthermore, concrete, mortar, or the like is placed (filled) in the rearward belt 26 of the foundation slab 22, and the low-rise support portion 22L and the high-rise support portion 22H of the foundation slab 22 are joined.

  The predetermined floor of the high-rise part 30H described above is appropriately set based on the weight of the high-rise part 30H and the bending strength of the foundation beam 32. In addition, the predetermined floor of the high-rise part 30H may be an intermediate floor or an upper floor of the high-rise part 30H, or may be the top floor.

  Next, the effect of this embodiment will be described.

  According to the present embodiment, the foundation slab 22 has the trailing band 26 extending along the boundary portion 22R between the low layer portion 30L side and the high layer portion 30H side in plan view. In this case, as the construction of the high-rise portion 30H proceeds, the high-rise support portion 22H sinks with respect to the low-rise support portion 22L of the foundation slab 22 with the trailing zone 26 as a boundary. At this time, the deformation (bending stress) generated at the boundary portion 22R between the low-layer support portion 22L side and the high-layer support portion 22H side of the foundation slab 22 is reduced by the deformation of the trailing band 26 and the like.

  By the way, the upper structure 30 has the foundation beam 32 which crosses the rear striking belt 26, and extends over the low layer part 30L and the high layer part 30H by planar view. In this case, as the construction of the high layer portion 30H of the upper structure 30 proceeds, the high layer side portion 32H sinks with respect to the low layer side portion 32L of the foundation beam 32. Therefore, a stress is generated at the boundary between the lower layer side portion 32L and the higher layer side portion 32H of the foundation beam 32.

  Further, the higher layer side portion 32 </ b> H of the foundation beam 32 is supported by the higher layer support portion 22 </ b> H of the foundation slab 22. As described above, the high-rise support portion 22H of the foundation slab 22 sinks as the construction of the high-rise portion 30H of the upper structure 30 proceeds. Therefore, the amount of settlement of the high-layer side portion 32H of the foundation beam 32 increases according to the amount of settlement of the high-layer support portion 22H of the foundation slab 22. As a result, the amount of subsidence of the high-layer side portion 32H with respect to the low-layer side portion 32L of the foundation beam 32 increases, and the stress generated at the boundary between the low-layer side portion 32L and the high-layer side portion 32H of the foundation beam 32 can be excessive. There is sex.

  As a countermeasure, in the present embodiment, as described above, when the amount of subsidence of the high-layer side portion 32H with respect to the low-layer side portion 32L of the foundation beam 32 exceeds a predetermined value, the hydraulic pressure that supports the low-layer side portion 32L of the foundation beam 32 Lower the jack 70 (jack down). Thereby, the amount of settlement of the lower layer side part 32L of the foundation beam 32 can be matched with the amount of settlement of the higher layer part. That is, in the present embodiment, the amount of settlement S of the high-layer side portion 32H with respect to the low-layer side portion 32L of the foundation beam 32 can be reduced or made zero. Therefore, the stress which generate | occur | produces in the boundary part of the low layer side site | part 32L and the high layer side site | part 32H in the foundation beam 32 can be reduced.

  As described above, in the present embodiment, the stress generated in the boundary portion between the lower layer side portion 32L and the higher layer side portion 32H of the foundation beam 32 is reduced while reducing the stress generated in the foundation slab 22 by the trailing band 26. Can do.

  In the present embodiment, the upper footing 52 of the low-rise side seismic isolation device 42L is previously constructed, and after lowering the hydraulic jack 70, the concrete is post-placed (post-construction) under the low-rise side seismic isolation device 42L. The lower footing 50 is formed. Thereby, the lower part of the lower layer side seismic isolation device 42 </ b> L is joined to the support surface 22 </ b> A of the foundation slab 22 via the lower footing 50. Therefore, the trouble of post-construction of the low-rise seismic isolation device 42L is reduced.

  Furthermore, in this embodiment, in order to form the lower footing 50 by post-casting concrete under the low-rise seismic isolation device 42L, the upper footing 52 is placed by post-stripping concrete on the low-rise seismic isolation device 42L. Compared with the case of forming, it becomes easier to post-work concrete. Therefore, the trouble of post-construction of the low-rise seismic isolation device 42L is further reduced.

  Next, a modification of the above embodiment will be described.

  In the above embodiment, the lower footing 50 of the low-rise seismic isolation device 42L is post-constructed after the hydraulic jack 70 is lowered, but the above embodiment is not limited thereto. For example, the upper footing 52 may be post-installed after the hydraulic jack 70 is lowered, or both the lower footing 50 and the upper footing 52 may be post-installed after the hydraulic jack 70 is lowered.

  Moreover, the joining method of the lower layer side seismic isolation device 42L and the upper structure 30 and the lower structure 20 can be appropriately changed. For example, the lower layer side seismic isolation device 42L may be modified by another joining method that does not include the upper footing 52 and the lower footing 50. The seismic device 42 </ b> L may be joined to the upper structure 30 and the lower structure 20. The same applies to the method of joining the high-rise seismic isolation device 42H with the upper structure 30 and the lower structure 20.

  Moreover, in the said embodiment, although the structure 10 is made into a basic seismic isolation structure, the said embodiment is not restricted to this. The structure may be, for example, an intermediate base isolation structure (intermediate floor base isolation structure). In this case, the lower side is the lower structure with the seismic isolation layer on the intermediate floor in between, and the upper side is the upper structure.

  Moreover, in the said embodiment, although the upper structure 30 is supported by the lower structure 20 via the low-rise side seismic isolation apparatus 42L and the high-rise side seismic isolation apparatus 42H, the said embodiment is not restricted to this. For example, as shown in FIG. 7, the lower layer portion 30 </ b> L of the upper structure 30 may be supported by the basic slab 22 of the lower structure 20 via a pillar 90.

  Specifically, the pillar 90 is made of steel such as a square steel pipe. A base plate 92 is provided at the lower end of the column 90. After the base plate 92 is installed on the support surface 22A of the foundation slab 22 via the temporary support base 94, its upper end is joined to a lower layer side portion 32L of the foundation beam 32 (not shown). In this state, the temporary support base 94 is disassembled and removed.

  As in the above-described embodiment, when the subsidence amount S (see FIG. 5 (B)) of the high-layer side portion 32H with respect to the low-layer side portion 32L of the foundation beam 32 becomes a predetermined value or more, it is installed around the column 90. The jack 96 is lowered, and the amount of settlement of the lower layer side portion 32L of the foundation beam 32 is adjusted to the amount of settlement of the higher layer side portion 32H. Thereby, the effect similar to the said embodiment can be acquired. Thereafter, concrete 98 is placed around the column base of the column 90, for example, as indicated by a two-dot chain line, and the column base of the column 90 and the support surface 22A of the foundation slab 22 are joined.

  Thus, the said embodiment is applicable not only to a base isolation structure but to a non-base isolation structure. In the modification shown in FIG. 7, the high layer portion 30 </ b> H of the upper structure 30 is supported by the lower structure 20 via a pillar, for example.

  Further, in the above embodiment, the trailing band 26 is formed in the lower structure 20, but the trailing band 26 can be omitted as appropriate. Even if the rear striking belt 26 is not provided, the lower layer of the foundation beam 32 is caused by the weight difference between the lower layer 30L and the higher layer 30H as the construction of the upper layer 30H of the upper structure 30 proceeds and the height increases. The high-layer side part 32H sinks with respect to the side part 32L.

  Moreover, in the said embodiment, although the foundation beam 32 is used as a horizontal member of the upper structure 30, the said embodiment is not restricted to this. As a horizontal member, a beam, a slab, etc. may be sufficient, for example.

  Moreover, in the said embodiment, although the hydraulic jack 70 was used as a jack, you may use another jack.

  Furthermore, in the said embodiment, although the low layer part 30L is provided in the outer peripheral part of the upper structure 30, and the high layer part 30H is provided in the center part of the upper structure 30, the said embodiment is not restricted to this. The arrangement (layout) of the low layer part 30L and the high layer part 30H can be changed as appropriate. For example, the low layer part and the high layer part may be arranged side by side. In addition, the upper structure may be provided with, for example, three or more parts having different heights.

  Specifically, the upper structure may be provided with, for example, a first layer portion, a second layer portion, and a third layer portion that increase in height in order. When the first layer portion and the second layer portion are adjacent to each other, the first layer portion is a low layer portion, and the second layer portion is a high layer portion. Further, when the first layer portion and the third layer portion are adjacent to each other, the first layer portion is a low layer portion, and the third layer portion is a high layer portion. Further, when the second layer portion and the third layer portion are adjacent to each other, the second layer portion is a low layer portion and the third layer portion is a high layer portion.

  As mentioned above, although one embodiment of the present invention was described, the present invention is not limited to such an embodiment, and one embodiment and various modifications may be used in combination as appropriate, and the gist of the present invention will be described. Of course, various embodiments can be implemented without departing from the scope.

10 structure 20 lower structure 22 foundation slab (lower structure)
22R boundary (boundary between the low and high floors of the foundation slab)
26 Trailing zone 30 Upper structure 30H High layer 30L Low layer 32 Foundation beam (horizontal member)
42 Seismic isolation device 42L Low-rise side seismic isolation device (Seismic isolation device)
70 Hydraulic jack (jack)
96 Jack S Subsidence amount (Subsidence amount on the high layer side with respect to the low layer side in the horizontal member)

Claims (3)

A construction method for constructing an upper structure having a low layer portion and a high layer portion joined to the low layer portion and having a height higher than the low layer portion on the lower structure,
As construction of the high-layer part supported by the lower structure proceeds, a jack that supports the low-layer part is lowered with respect to the lower structure.
Construction method of the structure. The lower structure has a trailing band extending along a boundary portion between the low layer portion side and the high layer portion side in a plan view,
The upper structure has a horizontal member that, in plan view, extends across the lower striking zone across the lower striking band and the high layer part, and the low layer part side is supported by the jack,
Lowering the jack when the amount of subsidence on the high-layer part side with respect to the low-layer part side of the horizontal member is a predetermined value or more
The construction method of the structure of Claim 1. Before lowering the jack, the upper part of the seismic isolation device arranged between the lower layer part and the lower structure is joined to the lower part part,
After lowering the jack, concrete is placed under the seismic isolation device to join the lower part of the seismic isolation device to the lower structure,
The construction method of the structure of Claim 1 or Claim 2.