JP3903553B2 - Staircase structure on the floor where seismic isolation devices are installed - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a staircase structure on a floor where a seismic isolation device is installed, in which when a seismic isolation device is added to an intermediate floor of an existing building, a stair connecting the intermediate floor and upper and lower floors is made to correspond to a displacement caused by shaking such as earthquake.
[0002]
[Prior art]
One method of retrofitting existing buildings is to add seismic isolation devices. In this construction method, axial support materials are placed on existing columns on the intermediate floor, the columns are temporarily separated from each other, the columns are connected to the separated intermediate parts by seismic isolation devices such as seismic isolation rubber, and then the axial force support is performed. It is a construction method that removes materials, and in the renovation, the construction scope is on the seismic isolation equipment installation floor and can be limited only to the periphery of the pillar, so there is an advantage that construction can be done without hindering daily use of the building is there.
[0003]
And in this construction method, after making the column a seismic isolation structure, a seismic isolation slit is formed in the wall etc. along the line of the column cutting level, so that the top and bottom of the building are completely separated, and only the seismic isolation device is used. Support building loads.
[0004]
As shown in FIG. 5A, a building subjected to this type of renovation has a seismic isolation slit 2a formed on a wall 2 constituting the staircase 1 as well. In the figure, reference numeral 3 is an intermediate floor column, 4 is a seismic isolation device interposed between the columns 3, and 5 is two stairs arranged in the staircase 1. Is arranged.
[0005]
[Problems to be solved by the invention]
In a building with the above seismic isolation structure, the building is relatively displaced in the horizontal direction at the position of the intermediate floor as shown in FIG. In such a case, if the lower side staircase 5 arranged in the staircase 1 is made of a rigid body as in the prior art, a horizontal shearing force acts on the staircase 5 at the vertical position of the slit 2a. The stairs 5 may be deformed or damaged by the horizontal force, and the vertical flow line of the stairs 5 which is the only evacuation route at the time of this kind of disaster may be cut off.
[0006]
The present invention solves the above problems, and its purpose is to ensure a sufficient evacuation flow line in the event of an earthquake, and to ensure sufficient safety when a person passes through the stairs when an earthquake occurs. It provides a staircase structure on the seismic isolation device installation floor.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, the present invention arranges a seismic isolation device on a column located on an intermediate floor of an existing building, and segregates the wall along the same level line as the installation position of the seismic isolation device. By forming a slit, the building is separated into an upper floor and a lower floor and supported by the seismic isolation device, and each step plate of the stairs arranged in the staircase of the seismic isolation device installation floor is , Composed of two plates, a step plate fixed to the side beam on the wall surface divided vertically by the seismic isolation slit, and a step plate fixed to the side beam on the center side of the staircase, and the free ends of both The upper and lower ends of the side girders on the wall surface side and the upper and lower ends of the side girders on the center side of the staircase are at the landing stage. Installed so that it can move relative to the floor in the width direction. It is an feature.
[0008]
As described above, in the present invention, when seismic motion is applied to the stairs, the stacked step plates expand and contract with each other in the width direction, and the entire stairs are displaced in the climbing direction, so that the horizontal direction is omnidirectional. Absorb the displacement over. This prevents damage to the staircase itself and maintains the step width dimension during an earthquake.
[0009]
Further, in the present invention, by providing an extendable guide beam on the lower side of the superimposed step plates and connecting the guide beams, the step plate can be applied even if a horizontal displacement other than the width direction of the stairs is applied. The members are restricted to expansion and contraction only in the width direction guided by the guide beam, thereby preventing a collision between the step plates.
[0010]
Furthermore, in the present invention, either the upper end or the lower end of the side girders on the wall surface side and the staircase center side is installed so as to be relatively movable in the ascending / descending direction with respect to the landing floor surface. Damage can be prevented.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Since the structure of the staircase is basically the same as the structure shown in FIG. 5 according to the conventional example, the same parts are denoted by the same reference numerals, and only new parts and parts to which new explanations are added are newly added. This will be described using various reference numerals.
[0012]
1 and 2, the staircase 1 is formed by forming a rectangular section in plan view surrounded by a wall 2 through each floor of the building, and on the floor where the seismic isolation device is installed, the floor can be accessed by a door 10. No. 12, the above-described intermediate landing 6, and the upper floor landing 14.
[0013]
And in this embodiment, the case where the seismic isolation slit 2a is formed in the wall 2 in the upper part of the intermediate landing 6 is shown, Therefore, between the intermediate landing 6 and the upper floor landing 14, the steel-made staircase 18 of this invention is shown. Is arranged.
[0014]
The staircase 18 is arranged along the wall surface of the wall 2 and is arranged at the center position of the staircase 1 and the inner wall side girder 20 connecting the dance halls 14 and 6 with a predetermined gradient, and connects the dance halls 14 and 6. The central girder 22 is composed of a movable step plate 24 having one end fixed to the inner wall side girder 20 in multiple stages and a fixed step plate 26 having one end fixed to the central side girder 22 in multiple stages. The free ends are overlapped with each other and are relatively movable in the width direction.
[0015]
The upper ends of the side girders 22 are fixed to the upper landing 14, and the lower ends of the side girders 20 and 22 are installed so as to be movable in the ascending direction with respect to the intermediate landing 6.
[0016]
In FIG. 1, reference numeral 23 denotes a handrail disposed on the center side of the steps 5 and 18. Further, although the pillar 3 and the seismic isolation device 4 are omitted in the present embodiment, they are basically the same as those in FIG. 5 and the seismic isolation slit 2a is formed on the seismic isolation device installation floor. .
[0017]
In the above, when the displacement L is generated from the normal state shown in FIGS. 1 and 2A, the lower end of the staircase 18 is lowered by the component force in the climbing direction of the displacement L with respect to the staircase 18 as shown in FIG. By shifting from the floor of the landing 12, the component force in the climbing direction is absorbed.
[0018]
Further, the movable step plate 24 moves relative to the fixed step plate 26 by the component force in the width direction of the staircase 18 with the displacement W, so that the component force in the width direction is absorbed.
[0019]
As described above, the stairs 18 reciprocates in the ascending direction while expanding and contracting between the step plates 24 and 26 according to the shaking, and the normal state is maintained with the step widths of the step plates 24 and 26 being kept constant. Thus, the upper and lower evacuation flow lines are secured while preventing the staircase 18 itself from being damaged.
[0020]
Next, a more detailed structure of the staircase 18 will be described with reference to FIGS.
[0021]
First, FIG. 3 shows a more detailed cross-sectional structure in the vicinity of the position where the staircase 18 having the above-described configuration is joined to the landing 6. In the figure, a step which is one step lower is formed on the front side of the floor slab 6a constituting the landing 6 and a steel plate guide plate 28 is embedded and fixed on this upper surface.
[0022]
On the other hand, between the lower ends of the side girders 20 and 22, the treads 30 and 32 connected to the lower portions of the step plates 24 and 26 are respectively arranged in a stacked state. Is movably installed on the upper surface of the front half of the guide plate 28. A movable mat 34 is laid on the upper surface of the rear half of the guide plate 28 to ensure flatness with the upper tread 30 in a normal state.
[0023]
The length of the guide plate 28 is the length of the displacement L × 2 times, which is the amount of movement of the tread plate 30, and a horizontal displacement occurs from the position shown in the figure. Held on. Further, when retreating as much as possible, the mat 34 is retreated on the guide plate 28 while being elastically deformed.
[0024]
Note that the maximum value of the displacement L is about 400 mm in actual dimensions in view of the scale of the Great Hanshin Earthquake. Therefore, the lower end of the staircase is supported on the landing 28 even if it moves forward and backward by 800 mm. Therefore, the length of the guide plate 28 is preferably set.
[0025]
Next, a guide beam 36 slidably connected between the movable step plate 24 and the fixed step plate 26 is disposed below the movable step plate 24 and the fixed step plate 26.
[0026]
As shown in FIG. 4, the guide beam 36 includes a cylinder 38 having a rectangular cross section fixed to the lower surface of the fixed step plate 26 along the width direction thereof, a piston 42 slidably inserted into the cylinder 38, A plunger 44 having one end connected to the piston 42 and the other end connected to the side beam 20 side, a spring 46 disposed in the cylinder 38 and compressing and urging the piston 42 in the pushing direction, and inside the cylinder 38, the piston A guide roller 48 that is fixed to 42 and contacts the upper member of the cylinder 38 is provided.
[0027]
Further, in order to eliminate the step between the step plates 24 and 26, a movable mat 50 is laid on the movable step plate 26 in the same manner as described above to ensure flatness between the two step plates.
[0028]
Therefore, according to this configuration, the movable girder 20 is always pressed against the wall 2 side by the pressing force of the spring 46 in the normal state shown in (a), and the width of the staircase 18 is kept constant.
[0029]
In this state, when a displacement W occurs as shown in (b) and the wall 2 moves forward, both the piston 42 and the movable step plate 24 move forward in the width direction, and the step width is resisted against the biasing pressure of the spring 46 and the mat 50. Reduce while pushing down. Although the displacement W extends in all directions, the guide beams 36 restrict the step plates 24 and 26 only by the horizontal component force in the width direction, and only the entire stairs 18 moves in the climbing direction. It becomes.
[0030]
In this state, the spring pressure reduces the impact during displacement and prevents excessive advancement.
[0031]
Thereafter, the expansion and contraction following the displacement is repeated, and when the vibration is stopped, the original state is restored again. Therefore, it is possible to prevent the staircase 18 itself from being damaged and falling off the dance hall by the above operation.
[0032]
Although FIG. 3 shows a case where only one guide beam 36 is provided, a plurality or all of the overlapping step plates 24 and 26 may be arranged.
[0033]
In the embodiment, the upper end of the staircase 18 is fixed to the landing 14 and the lower end is movably installed on the intermediate landing 6. However, it is needless to say that the arrangement may be reversed.
[0034]
【The invention's effect】
As is clear from the above description, according to the staircase structure on the seismic isolation device installation floor according to the present invention, it is possible to prevent the staircase from being damaged at the time of earthquake occurrence on the seismic isolation device installation floor. The safety of the stairs as an evacuation flow line can be sufficiently secured. Also, with this structure, even if there is a person who goes up and down the stairs during an earthquake, it can be raised and lowered safely.
[Brief description of the drawings]
FIGS. 1A and 1B are side sectional views of a staircase with a staircase according to the present invention at normal time and when horizontal displacement occurs.
FIGS. 2A and 2B are front cross-sectional views taken along a line AA in FIG. 1A at a normal time and when a horizontal displacement occurs.
FIG. 3 is an enlarged partial cross-sectional view showing a portion B in FIG.
4A and 4B are side cross-sectional views taken along the line CC of FIG. 3 when normal and when horizontal displacement occurs.
5 (a) and 5 (b) are explanatory diagrams showing problems in a staircase in a building having a base-isolated structure during normal times and when a displacement occurs due to an earthquake.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Staircase 2 Staircase wall 3 Pillar 4 Seismic isolation device 6 Middle landing 12 Landing 18 Stair 20 Inner wall side girder 22 Central side girder 24 Movable step plate 26 Fixed step plate 36 Guide beam

Claims (3)

Place the seismic isolation device on the pillar located on the middle floor of the existing building, and form the seismic isolation slit on the wall along the same level line as the installation position of the seismic isolation device, so that the building In a building that is separated from the lower floor and supported by the seismic isolation device,
Step plates arranged in the staircase on the floor where the seismic isolation device is installed are fixed to the side girders on the wall surface divided up and down by the seismic isolation slit, and the side girders on the center side of the staircase And a structure in which the free ends of both are overlapped so that they can move relative to each other along the width direction of the stairs, and the upper and lower ends of the side girders on the wall surface side, In addition, the staircase structure on the seismic isolation device installation floor is characterized in that at least one of the upper end or the lower end of the side beam on the center side of the staircase is installed so as to be relatively movable in the width direction with respect to the landing floor.   2. The seismic isolation device installation floor according to claim 1, wherein a guide beam capable of expanding and contracting in a width direction is provided at a lower portion of the overlapped step plates, and the step plates are connected to each other by the guide beam. Staircase structure.   3. The exemption according to claim 1 or 2, wherein either the upper end or the lower end of the side girders on the wall surface side and the staircase center side is installed so as to be movable relative to the landing floor in the up-and-down direction. Staircase structure on the seismic equipment installation floor.

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