JP3244572B2 - Fireproof structure of building - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fire-resistant structure of a building, and more particularly, to a fire-resistant building having three or more stories, such as an apartment house, a hospital, and a dormitory, which is long and large.

[0002]

2. Description of the Related Art Buildings of three stories or more for use in apartment houses, hospitals, dormitories, etc., must have a fire-resistant structure having a predetermined fire-resistant performance in accordance with the Building Standards Law, and have a predetermined earthquake-resistant structure. Since they must also have performance, many of them are constructed with a steel frame in which columns and beams are joined to a rigid frame structure (Japanese Patent Laid-Open No. 63-165629). By the way, the yield point of conventional steel materials at 350 ° C. decreases to nearly ／ of the normal temperature standard value, so that it is necessary to cover the periphery of steel frames such as columns and beams with a thick refractory coating material.

[0003] On the other hand, in recent years, fire resistant steel has been developed in which the strength at high temperatures is significantly increased as compared with conventional steel (hereinafter referred to as ordinary steel) by including elements such as chromium and molybdenum in minute amounts ("Architects"). "'93 .6: See pages 39-41). This refractory steel
Since it maintains a yield strength (yield point) of ／ or more of the normal temperature specification even at a high temperature of 600 ° C., it has been used as a pillar or a beam of a fire-resistant building (“Building Technology” '92.
4: See pages 170-183).

[0004]

However, when a long fire-resistant building is constructed using the above-mentioned fire-resistant steel, in the event of a fire, the strength at high temperatures is guaranteed, but the steel frame temperature is significantly higher than that of ordinary steel. Therefore, there is a fear that excessive thermal deformation occurs in the frame and the frame collapses. That is, in the case of a fire-resistant building composed of a steel frame of ordinary steel, the periphery of the steel frame is covered with a thick fire-resistant coating material to suppress the temperature of the steel frame to 350 ° C. or less at the time of fire. ), The beams 1, 1, ... and the columns 2, 2, ... have a small thermal expansion at the time of fire, and therefore, the thermal deformation of the frame is usually not a problem. On the other hand, in the case of a fire-resistant building composed of a steel frame made of fire-resistant steel, the temperature of the steel
Heating up to ° C. is permissible for structural stability, so the surroundings of the steel frame will be covered with a thin refractory coating. Therefore, in the event of a fire, the steel frame is heated to 600 ° C., so that thermal expansion cannot be ignored. In particular, in the case of a long fire-resistant building, as shown in FIG. 3B, the thermal expansions generated in the individual beams 3, 3,... And the columns 4, 4,. Excessive thermal deformation occurs at the edge of the building,
The frame could collapse.

[0005] In order to prevent excessive thermal deformation and collapse of the frame, the intense range of fire properties in the building should be reduced.
It is conceivable to divide the interior of the building with fire-resistant walls so that the number of columns and beams affected by the flame is minimized. However, if the reliant on the refractory compartment is too much, a plan such as a floor plan is restricted, and there is a problem that the room cannot be widely used.

The present invention has been made in view of the above circumstances, and can prevent an excessive deformation of a frame due to a fire, and furthermore, a collapse of the building, and can be applied to a building that can cope with various plans such as a floor plan. It is intended to provide a fireproof structure.

[0007]

According to a first aspect of the present invention, there is provided a fire-resistant structure for a building, comprising: a plurality of beams and columns;
Between any pair of columns, a pair of cantilever beams supported by each column are suspended with their free ends facing each other, and between the free ends of these paired cantilevers, A gap that can spatially absorb the extension of the cantilever in the event of a fire is provided.

According to a second aspect of the present invention, there is provided a fireproof structure for a building, wherein the building according to the first aspect is constructed by assembling a plurality of building units in a horizontal direction and a vertical direction. It is characterized in that at least a pair of building units composed of a beam and a cantilever are included.

[0009]

In the structure of the present invention, a beam spanned between any pair of pillars is divided into two, and between the divided beams, both beams in the event of a fire are provided. A gap is provided to allow for elongation of the beam. Therefore, even if a fire occurs, the thermal stress of each beam is absorbed by the gap. For this reason, according to the configuration of the present invention, even when the building is long, the thermal deformation is completed for each column (that is, for each building section or each building unit), and the heat is generated from beam to beam. Inconveniences caused by accumulating the elongation or deformation can be avoided. Therefore, it is possible to prevent the building from being excessively deformed due to the fire, and to prevent the building from being collapsed.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. In describing this embodiment, a fireproof structure of a three-story unit building will be described as an example. FIG. 1 is a perspective view showing a frame structure of a building unit applied to a fire-resistant structure of a building of this example, and FIG.
3 and 4 are enlarged perspective views showing the floor structure of the building unit, and FIG. 5 is an enlarged perspective view of the floor unit of the building unit. FIG. 6 is an enlarged sectional view showing a ceiling portion of the building unit.

First, as shown in FIG. 1, a building unit 5 (5L, 5R) of this example is an ordinary building having a box-like shape in which steel beams are bridged between upper and lower ends of steel columns at four corners. It roughly corresponds to the shape and size of one half of the unit (hereinafter referred to as a box-shaped unit) in the longitudinal direction, and the ceiling structure is supported in a cantilevered state by only two pillars 6 and 6. As shown in the upper right of the figure, the building unit 5 of this example includes a unit 5R (hereinafter referred to as a right unit for convenience) corresponding to the shape and size of the right half of the box-shaped unit. As shown, there are two types, a unit 5L (hereinafter referred to as “left unit” for convenience) corresponding to the shape and size of the left half of the box-shaped unit. The configuration is substantially the same except that the shapes of the end surfaces on the end side are different from each other.

That is, the building unit 5 (5L, 5R)
Are two pillars 6 and 6 erected at two corners,
6 each one floor girder 7 and ceiling girder 8 connecting the upper and lower ends
And a pair of cantilevered floor beams 9, 9 and cantilevered ceiling beams 10, which project from the upper and lower ends of each column 6 in a direction orthogonal to the floor girders 7 and the ceiling girders 8 and in the same direction as each other. 10 and a plurality of floor panels 1 attached between the cantilever floor beams 9, 9
, And a plurality of ceiling beams 12, 12,... Bridged between the ceiling girders 10, 10, form a box-shaped skeleton. This skeleton is shown in FIG. 2 and FIG. Wall panel (outer wall panel 13, inner wall panel 14, boundary wall panel 15)
Alternatively, the ceiling panel 16 shown in FIG. 6 is attached by using a fixing tool such as a bolt or a tapping screw. Which type of wall panel is attached to which side of the building unit 5 is determined by which part of the unit building the building unit 5 constitutes.

Here, each of the columns 6 is a square refractory steel pipe having a proof stress of at least ^{２ of the} standard value at room temperature even at a high temperature of 600 ° C., that is, a proof strength of 163 N / mm ² or more required for the structure. (SS400 material). The floor girder 7 and the ceiling girder 8 are both 2,163 m long.
m, and a groove-shaped refractory steel (coefficient of thermal expansion α = 1.45 × 10 ^-5 , S
S400 material), and the cantilever floor beam 9 and the cantilever ceiling beam 10 each have a length of 2,751 mm and a groove-shaped refractory steel (heat expansion coefficient α = 1.45 × 10 ⁻⁵ , SS400 material). Note that ordinary small channel steel (ordinary steel) is used for the ceiling beam 12 that does not require a predetermined fire resistance.

At the upper end of each column 6, as shown in FIG.
Two U-shaped joint pieces 17 orthogonal to each other,
17 are projected in the horizontal direction by welding, and the columns 6 and the ceiling girders 8 and the cantilever ceiling girders 10 are connected by welding via these joint pieces 17, 17.
Also, two U-shaped joint pieces 18, 18 are protruded in the horizontal direction by welding at the lower end of each column 6, and each column 6 is connected to the floor girders via these joint pieces 18, 18. 7 and the cantilever floor girder 9 are connected by welding. In addition, each joint piece 17 and 18 also has 600
Refractory steel whose proof stress at high temperature of ℃ is guaranteed is used.

Also, the upper and lower end surfaces of the column 6
Upper obstruction plate 1 made of fire-resistant steel with guaranteed proof stress at high temperature
9. The lower closing plate 20 is welded. Upper and lower floor joining bolts 21 are implanted at the center of the upper closing plate 19, and positioning guide pins 22, 22 are located at two diagonally opposite corners on both sides thereof. It has been planted. In addition, each guide pin 22
Due to the nature of the positioning function, it is formed to be longer in axial length than the upper and lower floor joining bolts 21. On the other hand, the lower blocking plate 20 is provided with a bolt insertion hole 23 through which a joint bolt 21 for the upper and lower floors (of the lower floor building unit 5) is inserted at a central portion, and two diagonally opposite sides thereof. Near the corners are the guide pins 22, 2 (of the lower building unit 5).
The pin insertion holes 24, 24 through which the respective holes 2 are inserted are formed. Further, the pillar 6 has two sides facing the inside of the building unit 5 excluding the upper and lower ends, and is fire-coated in advance in a factory with a fire-resistant coating material 25 such as a ceramic fiber or a calcium silicate plate having a thickness of 12.5 mm. I have.

Next, in the floor structure of the building unit 5, each of the floor panels 11 is made of an ALC plate (Autoclaved Light Weight Concrete; cellular concrete plate) having a thickness of 125 mm. JI
SA 1304 fire resistance test method for building structural parts). The floor panels 11, 11,... Are rectangular, as shown in FIGS. 3 and 4, with short sides along the long sides of the cantilever floor girders 9, 9, and long sides sequentially adjacent to each other. In the state, it is bridged between the cantilever floor girders 9, 9, and one end of each short side end is provided with a one-side rivet 2 on the inner surface of the web of the cantilever girders 9, 9 as shown in FIG.
Each cantilever floor is sandwiched between receiving members 27, 27 and holding members 28, 28 fixed by 6, 26,... And fastened by bolts 29, 29 and nuts 30, 30 penetrating therethrough. It is fixed to the girder 9.

As shown in FIGS. 3 and 4, a concave portion 31a having a rectangular cross section and a convex portion 31b having a rectangular cross section are provided on the upper ends of the opposing side end surfaces of the adjacent floor panels 11, 11, respectively. Are superimposed on each other. Here, FIG. 3 schematically shows the floor structure of the right unit 5R,
As shown in the figure, in the right unit 5R, a protrusion 31b of the floor panel 11 is provided at the upper end on the free end side of the floor structure. On the other hand, FIG. 4 schematically shows the floor structure of the left unit 5L. As shown in FIG. 4, in the left unit 5L, a concave portion 31a of the floor panel 11 is provided at the upper end on the free end side of the floor structure. ing.

On the upper surface of the upper flange and the opening surface (excluding the portion intersecting with the floor panel 11) of the floor girder 7 and the cantilever girder 9, 9, a 12.5 mm thick ceramic fiber or calcium silicate plate or the like is provided. The refractory coatings 32 are covered. On the upper surface of the floor panel 11, joists 33,...
The floor joists 34, 34,... Are attached to the upper surfaces of the floor joists 34, 34,.

As shown in FIG. 6, in the ceiling structure of the building unit 5, ceiling beams 12, 12,... Are bridged between opposing cantilever ceiling beams 10, 10. , 12, ... are a pair of gusset plates 36,
37, both ends are cantilevered ceiling girders 10,
It is fixed to 10. At the lower end of each ceiling beam 12,
Wooden ceiling joists 38, ... are installed, and ceiling joists 38, ...
Are attached to the lower ends of the ceiling joists 38, in a direction perpendicular to the longitudinal direction of the ceiling joists 38,..., And a gypsum board or the like is attached to the lower surface of the ceiling joists 39, 39,. A ceiling panel 16 is attached. As shown in the figure, a refractory coating material 40 such as a ceramic fiber or calcium silicate plate having a thickness of 12.5 mm is provided on each of the ceiling girders 8 and 10 from the lower flange lower surface to the upper flange upper end via the opening surface. Is covered.

The outer wall panel 1 of the above wall panels
3 is, for example, 100 mm thick A as shown in FIG.
It is made of fire-resistant material such as LC plate with fire resistance time (according to JIS A 1304 fire resistance test method for building structure), and cantilever ceiling beam 9 and floor beam 7, and cantilever ceiling beam 10 and ceiling beam via rock wool. 8 is fastened. The inner wall panel 14 has a thickness of 6 which is a laminate of a calcium silicate plate and a gypsum board.
It is formed of a fire-resistant laminated plate of 8 mm, and a space between the outer wall panel 13 and the inner wall panel 14 is filled with a sound absorbing heat insulating material such as glass wool or rock wool. Further, as shown in FIG. 5, the partition wall panel 15 separates a space for each door, and is formed of a laminated plate having a thickness of 116 mm formed by laminating a calcium silicate plate and a gypsum board containing glass fiber. Defines a fireproof zone with a fireproof time of 1 hour or more (according to JIS A 1304 fire test method for building structural parts).

Next, with reference to FIG. 7, an assembling procedure of a three-story unit building constructed using the unit buildings 5 (5R, 5L), 5 (5R, 5L),. explain. The building unit 5 having the above configuration is constructed such that the right unit 5R and the left unit 5L are paired with each other, are produced in a factory in advance in a size that can be transported, and then transported to a building site to be constructed and assembled. Is done. The assembling is performed, for example, in the operation sequence shown in FIGS. That is, first, as shown in FIG. 3A, an iron plate 42 is placed on a pre-constructed foundation 41, and
A crane truck 43 is arranged on the iron plate 42 as shown in FIG. Then, the first-floor building units 5 (5R, 5L) are sequentially lifted by a crane and installed on one half of the foundation 41. At this time, as shown in FIG. 8, the right unit 5R and the left unit
L and the free ends of the corresponding cantilever floor beams 9 and 9 and the free ends of the corresponding cantilever ceiling beams 10 and 6 are 6
While facing each other with a gap of 0 mm,
Fasten and fix to 1 with anchor bolts. The left side unit 5L is installed first, and thereafter, the concave portion 31a of the floor panel 11 on the side where there is no pillar of the installed left side unit 5L.
On the upper surface, the floor panel 11 on the side without the pillar of the right unit 5R
The right unit 5R is installed in a state where the lower surface of the convex portion 31b is placed and contacted with a predetermined overlapping width. Further, adjacent building units 5, 5,... Are effectively joined structurally.
In addition, although the structurally effective joining is not performed between the right unit 5R and the left unit 5L, which form a pair, the columns 6, 6, ... are adjacent to each other (not forming a pair). With respect to each of the building units 5, 5,..., A structurally effective column-to-column bolt connection is performed using a horizontal connection plate (not shown), and these building units 5, 5,.
5, ... are strongly connected.

Next, each second-floor building unit 5 (5R, 5L) is assigned to the corresponding first-floor building unit 5 (5
R, 5L). At this time, accurate positioning is performed only by overlapping the pin pins 24 in the second-floor building unit 5 with the guide pins 22, 22 of the capital in the first-floor building unit 5 being inserted into the pin insertion holes 24, 24 of the first-floor building unit 5. Since the upper and lower floor joining bolts 21 of the column capital in the floor building unit 5 are inserted into the bolt insertion holes 23 of the column bases in the second floor building unit 5, they are fastened with the joining nuts (not shown) and the upper and lower floor joining bolts 21. This effectively bolts the upper and lower floors structurally. Also, the second-story building units 5, 5 in which the columns 6, 6,... Gather and are adjacent to each other (do not form a pair) are structurally and effectively bolted to each other using a horizontal joining plate (not shown).
In addition, structurally effective joining is not performed between the paired right unit 5R and left unit 5L.
Next, the third-floor building units 5 (5R, 5L), 5 (5R,
5L) are stacked on the second-floor building units 5, 5,... In the same manner as above and fixed to the second-floor units 5, 5,..., And the columns 6, 6,. The three-story building units 5 and 5 (which do not form a pair with each other) are structurally and effectively bolted between the columns. After that, a roof is installed above the third-floor building units 5 (5R, 5L), 5 (5R, 5L),. Next, as shown in FIG. 7C, the crane truck 43 is moved to the outside of the foundation 41, and the building unit 5,
5,... Are sequentially stacked in the same manner as described above, a roof is installed, and the frame of the three-story unit building is roughly completed as shown in FIG.

In the three-story unit building, adjacent (not forming a pair) building units 5
(5R, 5L) has a thickness of 1 between columns 6, 6, ...
A refractory coating such as 2.5 mm ceramic fiber or calcium silicate is coated on site. As a result, the assembled pillars 6, 6,...
Together with the refractory coating, so that the average steel temperature of each column 6 does not exceed 600 ° C. under a fire lasting at least one hour (note that the column is It is permissible for structural safety that the average steel temperature of No. 6 rise to 600 ° C.).

Adjacent to each other (not forming a pair with each other)
Between the building units 5 (5R, 5L), the cross section between the cantilever floor girders 9 (or floor girders 7) and the cantilever ceiling girders 1
0 (or ceiling beam 8), thickness 12.5
A refractory coating such as a ceramic fiber or a calcium silicate plate having a thickness of 1 mm is coated on site. Further, between the pair of building units 5 (5R, 5L), a cross section between the cantilever beams 9 and 9 (a gap of 60 mm) and a cross section between the cantilever ceiling beams 10 and 10 (a gap of 60 mm). In the field, cantilever floor beams 9, 9 on both sides and cantilever ceiling beams 1
A fire-resistant coating material (not shown) such as a ceramic fiber or a calcium silicate plate having a thickness of 12.5 mm is placed over the 0 and 10 layers. As a result, two cantilever floor girders 9 (or floor girders 7) and two cantilever ceiling girders 10 that gather adjacently
(Or ceiling girders 8) are collectively fireproofed together with the refractory coatings 32, 40 and floor panels 11, 11 previously installed in the factory, thereby providing protection under fire lasting at least one hour. The average steel material temperature of the cantilever floor girder 9, the floor girder 7, the cantilever ceiling girder 10, and the ceiling girder 8 does not exceed 600 ° C. (the average steel temperature of these girder rises to 600 ° C.). Heating is acceptable for structural safety).

Further, a cross-over member which is the same as the floor surface material 35 is stuck on the part between the cantilever floor girders 9 (or the floor girders 7) at the site, and the floor of the same floor is Continuity and uniformity are ensured. Similarly, a cross-over material that is the same as the ceiling surface material 16 is adhered on the cross-over portion between the cantilever ceiling beams 10 (or the ceiling beams 8), and the continuity of the ceiling surface on the same floor is applied. And uniformity are ensured. In addition, these cross-floor materials and cross-ceiling materials are members having no proof stress, and when discussing structural strength, it can be considered that they do not contribute to joining between units at all.

Next, the operation of the fireproof structure of this embodiment will be described. A fire occurred inside and outside of the three-story unit building, whereby the cantilever floor beams 9, 9 and cantilever ceiling beams 10, 10 of each building unit 5 (5R, 5L) were 600.
Suppose it is heated to ° C. The cantilever floor beam 9 and the cantilever ceiling beam 10 each have a length of 2,751 mm and a coefficient of thermal expansion α of 1.45 × 10 ^−5. It thermally expands by about 24 mm toward the end face. However, as shown in FIG. 8 and FIG. 9, opposing cantilever floor beams 9, 9 (cantilever ceiling beams 10, 10).
Are provided with a space of 60 mm between the free end faces thereof, so that the cantilever floor beams 9, 9 (cantilever ceiling beams 10,
Even if 10) is extended, the thermal stress is completely absorbed, leaving a gap of about 12 mm, and the cantilever floor beams 9, 9 (cantilever ceiling beams 10, 10) are pressed to each other. Absent. Therefore, the extension of the cantilever floor girders 9, 9 (the cantilever ceiling girders 10, 10) is self-contained in each building unit 5 and does not affect the adjacent building unit 5. Therefore, it is possible to avoid the addition and accumulation of the elongation of the beam from beam to beam of the adjacent building unit 5. For this reason, excessive deformation of the whole building is not seen, and the collapse of the building can be prevented. Further, since the thermal expansion of the beam is completed for each building unit 5, it is not necessary to provide fireproof compartments. That is, since the interior of the building does not need to be partitioned by the fire-resistant partition walls as in the related art, the interior of the building can be widely used, and various plans such as a floor plan can be supported. In addition, the floor panel 11 of the left unit 5L,
As shown in FIG. 8, the floor panel 11 of the right unit 5R is configured such that the convex portions 31b and the concave portions 31a are overlapped with a predetermined overlap width, and as the cantilever floor beams 9 extend,
Since the cantilever floors 9 and 9 are slid in the direction in which the overlap width increases, the floor panels 11 and 11 are stretched.
There is enough room for collisions. In addition, ALC
Since the floor panels 11 and 11 made of the plate are strong against the compressive force, there is no possibility that the floor structure collapses.

Although the embodiment of the present invention has been described in detail with reference to the drawings, the specific configuration is not limited to this embodiment, and changes in design and the like can be made without departing from the gist of the present invention. Even if there is, it is included in the present invention. For example, in the above embodiment, an example in which the fire-resistant structure of a building is applied to a three-story unit building is shown.
The present invention may be applied to a building by a conventional construction method, and may be applied not only to a three-story building but also to a two-story building or a four-story or more building. In addition, it is not necessary to use all cantilever beams, and they may be used together with ordinary beams. Further, in the above-described embodiment, the case where the building unit has a ramen structure has been described. However, the type of the frame is not limited to the ramen structure, and may be a pin brace structure or a wall structure.
In addition, opposing cantilever floor girders 9, 9 (cantilever ceiling girders 1)
0, 10) are separated from each other in structural strength, and are members that do not contribute to structural strength, that is, floor materials, wall materials, ceiling materials, etc., and cantilever floor beams 9, 9 (cantilever ceiling beams 10, 10). ) Can be connected.

The pillar 6, the cantilever floor girder 9, the cantilever ceiling girder 10, the floor girder 7, and the ceiling girder 8 are not limited to rectangular steel pipes and channel steel. For example, an H-beam or an I-beam may be used. further,
Not only fire-resistant steel but also ordinary steel may be used.

In the above-described embodiment, the floor girders and the ceiling girders corresponding to the girder direction of the box-shaped unit are divided into two to form cantilever floor girders 9, 9 (cantilever ceiling girders 10, 10), respectively. However, in the case of a frame in which thermal deformation in the direction of the wife cannot be neglected, the floor girder and the ceiling girder corresponding to the wife direction of the box-shaped unit are appropriately divided into two, and a cantilever floor girder (a cantilever ceiling girder), ). Further, in the above-described embodiment, the case where the pair of cantilever floor beams 9 and 9 and the cantilever ceiling beams 10 and 10 are set to the same size has been described. However, the present invention is not limited to this, and one is long and the other is short. May be set. For example, each of the pair of cantilevered floor girders 9 and 9 and cantilever ceiling girders 10 and 10 corresponds to a case where the beam is divided at a portion where the bending stress of the beam of the box-shaped unit becomes “0”. The length dimension may be set.

[0030]

As described above, in the fire-resistant structure of a building according to the present invention, the beam bridged between any pair of columns is divided into two beams, Since a gap is provided between the beams and the beams in anticipation of the elongation of both beams at the time of a fire, even if a fire occurs, the thermal stress of each beam is absorbed by the gaps. For this reason, according to the configuration of the present invention, even when the building is long, the thermal deformation is completed for each column (that is, for each building section or each building unit), and the heat is generated from beam to beam. Inconveniences caused by accumulating the elongation or deformation can be avoided. Therefore,
Excessive deformation of the building due to a fire, and thus collapse of the building, can be prevented.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a frame structure of a building unit applied to a fireproof structure of a building according to an embodiment of the present invention.

FIG. 2 is an enlarged perspective view showing a pillar portion of the building unit.

FIG. 3 is an enlarged perspective view showing a floor structure of the building unit.

FIG. 4 is an enlarged sectional view showing a floor structure of the building unit.

FIG. 5 is an enlarged sectional view showing a floor portion of the building unit.

FIG. 6 is an enlarged sectional view showing a ceiling portion of the building unit.

FIG. 7 is a perspective view showing an example of an assembly procedure of the unit building of the embodiment.

FIG. 8 is a perspective view showing an example of assembly of the unit building of the embodiment.

FIG. 9 is a diagram showing a frame of the unit building in a substantially completed state.

FIG. 10 is an explanatory diagram used for describing a conventional technique.

[Explanation of symbols]

 5 building unit 5R right unit (pair of building units) 5L left unit (pair of building units) 6 pillar 7 floor girder (beam) 8 ceiling girder (girder) 9 cantilever floor girder (cantilever) 10 cantilever ceiling girder (Cantilever)

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) E04B 1/94 E04B 1/348

Claims (2)

(57) [Claims] Claims: 1. In a steel-based building in which a frame is composed of a plurality of beams and columns, an arbitrary pair of columns is provided between columns.
A pair of cantilever beams supported by each column are hung with their free ends facing each other, and between the free ends of these paired cantilever beams, the elongation of these cantilever beams in the event of a fire is limited. A fire-resistant structure for a building, characterized by being provided with a gap that can be temporarily absorbed. 2. The building is configured by assembling a plurality of building units in a horizontal direction and a vertical direction, and the building units include at least one pair of building units including columns, beams, and cantilevers. The fire-resistant structure of a building according to claim 1, wherein the fire-resistant structure is included.