JP2001115576A - Fireproof partition wall construction method of structural building - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fireproof partition wall construction method constituting the fireproof division of a steel structural building. SOLUTION: The lower flange of a steel frame beam and the upper runner of a partition wall by a joint material deforming vertically, even when the steel frame beam is at a high temperature by a fire and large deflection is produced, the joint material follows up and deforms, and excessive load is not applied on the just-under partition wall.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention belongs to the technical field of a fire partition wall construction method for forming a fire protection section of a steel structure building.

[0002]

2. Description of the Related Art In the event that a fire occurs, the fire prevention section of the building is required to confine the fire in the room (space) where the fire started, and to prevent the fire from expanding into adjacent upper, lower, left and right spaces, and It aims to ensure the safety of evacuation and fire fighting activities.

[0003] Therefore, a fire protection section of a steel structure building is often composed of pillars and beams coated with a fireproof coating, floors and walls.
Therefore, many fire prevention partition wall construction methods in which a partition wall is provided immediately below a steel beam provided with a fireproof coating have been implemented.

[0004] In the current fire resistance regulations, the steel material temperature of steel members (general steel) is evaluated at an allowable value of 350 ° C. As for the deformation of the steel beam, there is no problem of deformation because the reduction of the proof stress of the steel material is small up to the allowable temperature, and a partition wall method shown below is disclosed. For example,

[0005] Japanese Unexamined Patent Publication No. 6-146441 discloses a "supporting device for a wall in a building", in which a metal fitting and a runner are mounted under a steel beam provided with a fire-resistant coating, and partitions are provided on both sides of the runner. In this configuration, a wall plate is attached to the wall.

The “fire-prevention section wall for steel frame” described in Japanese Patent Application Laid-Open No. 9-60157 has a downward-facing plate provided on the lower surface of a flange of a steel beam, and a partition wall composed of two wall plates is provided on the same plate. Are mounted via an elastic sealing material.

Japanese Patent Application Laid-Open No. 10-245910, particularly, “Fireproof Sections with Column and Beam Walls” described in FIG. 7 has a thermal foaming property between a lower surface of a fire-resistant coated steel beam and an upper surface of a partition wall. It has a configuration in which no gap is formed between the partition wall and the steel beam by applying the refractory paint.

[0008] By the way, in June 2000, the fire standard design of steel structures has been greatly changed due to the introduction of the performance standardization of the Building Standard Law. That is, it is estimated that the allowable steel material temperature (general steel) of a steel-framed building is defined by an allowable value of 500 to 600 ° C., which is considerably higher than the conventional 350 ° C. Therefore, it is considered that large deformation occurs in the steel beam.

FIG. 8 shows the time transition of the steel material temperature at the time of fire. 400 mm x 200 mm cross section
When a H steel beam of × 8 mm × 13 mm is covered with a calcium silicate plate (thickness: 40 mm) containing inorganic fibers, the temperature of the steel material subjected to standard fire heating (flame temperature) is measured. The steel material temperature of one side heating with a partition wall is as shown by a curve (a), which is lower than the curve (b) showing the steel material temperature of three surface heating without a partition wall, and the temperature is multiplied by 0.7 as a coefficient. Temperature.

Next, according to the results of the measurement of the steel material temperature and the deflection in the load heating experiment of the steel beam shown in FIG. 9, the steel material temperature at the end of the load heating is 574 ° C. Therefore, as shown in FIG. 9 above, the steel material temperature assuming one-sided heating of the steel beam is 402 ° C. obtained by multiplying the aforementioned 574 ° C. by 0.7.
Is obtained, the time to reach the steel material temperature is also estimated to be 135 minutes from FIG. Further, the bending amount δt of the steel beam at the above-mentioned time point can be read as 25 mm from FIG. The allowable bending amount δt of the ISO specified value is δt =
L ² /400h=162.6 mm (where L is the span and h is the beam) and can be estimated to be a value obtained by multiplying the coefficient by 0.15.

The amount of deflection δt = 25 mm is a large deformation corresponding to several times the amount of deflection δ caused by a load on a beam assumed in a normal design. Further, when the beam h and the span L of the steel beam increase, the bending amount δt further increases.

[0012]

SUMMARY OF THE INVENTION In a fire-resistant partition wall construction method in which a partition wall is provided directly below a steel beam provided with a fire-resistant coating, when the steel beam is heated by a fire and the steel material temperature rises, Although large bending deformation occurs in the steel beam as described above, none of the above-mentioned prior arts is designed with the above-described large bending amount δt, so that the partition wall is crushed by the load of the steel beam to crack. There is a possibility that the fire may be caused, for example, and the flame-shielding performance may be impaired, and the fire may spread to an adjacent room (space).

Accordingly, an object of the present invention is to prevent the partition wall immediately below from being damaged by the load of the steel beam, such as being cracked by the load of the steel beam, even if the steel beam is heated to a high temperature and greatly bent by the fire. Thus, there is provided a fire-resistant partition wall construction method for a steel structure building capable of ensuring the safety of occupants to evacuate and extinguish fires without the risk of impairing the flame-insulating performance or spreading the fire to an adjacent room (space). It is to be.

[0014]

As a means for solving the above-mentioned problems, a fire-resistant partition wall construction method for a steel structure building according to the first aspect of the present invention is described below. In the fire-prevention partition wall construction method provided with a partition wall, the lower flange of the steel beam and the upper runner of the partition wall are connected by a vertically deformable connecting material, and the fire causes the steel beam to be heated to a high temperature, causing a large bending. Also, it is characterized in that the connecting member is configured to follow and deform so as not to apply an excessive load to the partition wall immediately below.

According to a second aspect of the present invention, in the method for constructing a fire-resistant partition wall of a steel structure building according to the first aspect, a method is provided between the lower flange of the steel beam and the upper runner of the partition wall.
An interval larger than the amount of deflection assumed at the time of the fire-resistant design temperature of the steel structure is secured, and the lower flange of the steel beam and the upper runner of the partition wall are connected to each other by a connecting member that deforms in the vertical direction at the interval. It is characterized by the following.

[0016]

1 to 5 show a first embodiment of the present invention.
1 and 2 show a first embodiment of a fire-resistant partition wall construction method for a steel structure building according to the invention described in 2 and 2;

According to the first and second aspects of the present invention, the lower surface of the lower flange 2a of the steel beam 2 and the upper surface of the upper runner 4 of the partition wall 3 are connected by a connecting member 1 which is deformed in the vertical direction. When the steel beam 2 has a high temperature due to a fire and causes a large deflection, the connecting member 1 is deformed to follow, as shown in FIGS. 4 and 5, so that an excessive load is not applied to the partition wall 3 immediately below. It is characterized by the following.

In the case of FIG. 1, the steel beam 2 made of an H-shaped steel material is coated with a fireproof coating 6 by spraying the whole surface with rock wool. However, for example, JP-A-6-14
As described in Japanese Patent No. 6441, a fire-resistant coating may be applied with a calcium silicate plate or the like mixed with inorganic fibers.

The illustrated partition wall 3 has two wall plates 3a.
3a is fixed to the side surfaces of the upper runner 4 and the lower runner 5 by means such as screws (not shown), but the structure is not limited to this example. The wall plate 3a
, A refractory member such as a gypsum board or an ALC board is also used.

The distance between the lower surface of the lower flange 2a of the steel beam 2 and the upper surface of the upper runner 4 is, as apparent from the comparison between FIGS. 2 and 3 and FIGS. An interval larger than the amount of bending assumed at the time of temperature is secured. In the space, the lower surface of the lower flange 2a of the steel beam 2 and the upper surface of the upper runner 4 of the partition wall 3 are connected by the above-described vertically deformable connecting member 1 (the invention of claim 2).

The connecting member 1 shown in FIGS. 2 to 5 has a hinge-like structure in which two upper and lower movable plates 1g and 1g are rotatably connected by a central hinge 1b. At both ends, mounting plates 1e are mounted with hinges 1a, 1c,
The mounting plate 1e is connected to the steel beam 2 and the upper runner 4 of the partition wall 3 by bolting or the like. Therefore, the connecting member 1 has not only the effect of supporting the steel beam 2 and the partition wall 3 but also, when the steel beam 2 is deformed, the upper and lower two movable plates 1g and 1 as shown in FIGS.
g bends and rotates around the hinge 1b to deform following. A plurality of the connecting members 1 are provided in the in-plane direction.

The space between the lower surface of the lower flange 2a of the steel beam 2 and the upper surface of the upper runner 4 is filled with a rock wool material 7 as shown in FIG. The rock wool material 7 plays a role of fire resistance of the connecting material 1 and further does not hinder the following deformation of the connecting material 1 because the material is flexible. Similarly, a fireproof coating 6 is also provided around the rock wool material 7.
Is being sprayed. Although the rock wool material 7 is used in the present embodiment, any material may be used as long as it plays a role of fire resistance of the connecting material 1 and does not hinder the following deformation.

Accordingly, in the case of the above-described fire-preventive partition wall method, if the steel beam 2 becomes high temperature due to the fire and causes a large downward bending, the connecting member 1 is moved to the steel beam as shown in FIGS. 2 and does not transmit the load of the steel beam 2 to the partition wall 3 immediately below. Therefore, the partition wall 3 does not suffer damage such as being crushed by the steel beam 2 and causing a crack, and furthermore, there is no possibility that the flame shielding performance is impaired and the adjacent room (space) spreads.

FIG. 6 shows another embodiment of the connecting member. This is because the cylindrical sheath 8c is provided downward on the lower surface of the lower flange 2a of the steel beam 2 and the sheath tube 8c is provided.
The lower end of the rod 8a inserted into the hollow part is fixed to the upper surface of the upper runner 4. A piston 8b for generating friction with the inner wall of the sheath tube 8c is provided at the tip of the rod 8a. Therefore, in the above case, the steel beam 2
The partitioning plate 3 not only produces a supporting effect due to the friction between the piston 8b and the sheath 8c, but also deforms the steel beam 2 to follow and deform the rod 8a in the vertical direction, thereby deforming the steel beam 2. It has a configuration corresponding to. The space between the lower surface of the lower flange 2a and the upper runner 4 is sufficiently provided as in the first embodiment so that the upper end of the piston 8b does not interfere with the bottom surface of the cylinder 8.

Further, the piston 8b has a spherical shape, and the rod 8a can be adapted to any direction in the sheath 8c by making the thickness of the rod 8a smaller than the diameter of the piston 8b. It has become.

The cylinder 8 and the rod 7 may be configured upside down, without being limited to the above case.

Next, FIG. 7 shows another embodiment of the connecting member. In this case, the mild steel 9 having an intermediate portion formed in a loop shape is used, and the upper end of the same mild steel 9 is connected to the lower surface of the lower flange 2 a and the lower end is connected to the upper surface of the upper runner 4. Accordingly, in the above case, not only does the steel member 9 have the effect of supporting the steel beam 2 and the partition wall 3, but if the steel beam 2 is greatly bent, the diameter of the loop of the intermediate portion of the steel mild steel 9 is reduced. By changing the size, it is possible to follow and deform vertically.

[0028]

[Effects of the present invention] According to the fire partition wall method for steel structures according to the present invention described in the present invention, a vertically deformable connecting member is provided in the gap between the lower surface of the lower flange of the steel beam and the upper surface of the upper runner. As a result, when the steel beam is heated to a high temperature due to a fire and large bending occurs, the connecting member deforms to follow the bending deformation of the steel beam. Therefore, the partition wall immediately below is not damaged by the load of the steel beam, such as being crushed by the load of the steel beam and causing a crack, and furthermore, the flame shielding performance is impaired, and there is no possibility that the fire spreads to an adjacent room (space). Therefore, safety of the evacuation and fire fighting of the occupants can be ensured.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing an embodiment of a fire-resistant partition wall method for a steel structure building according to the present invention.

FIG. 2 is a perspective view showing an embodiment of a fire-resistant partition wall construction method for a steel structure building according to the present invention.

FIG. 3 is a front view showing a normal state of the connecting member.

FIG. 4 is a front view showing a state in which the connecting member is deformed.

FIG. 5 is a perspective view showing deformation of a connecting member when a steel beam is bent.

FIG. 6 is a front view showing another embodiment of the connecting member.

FIG. 7 is a front view showing another embodiment of the connecting member.

FIG. 8 is a diagram showing a relationship between steel material temperature and time of a steel beam.

FIG. 9 is a diagram showing the results of measurement of the temperature and deflection of a steel material by a load heating experiment on a steel beam.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Connecting material 2 Steel beam 2a Lower flange 3 Partition wall 3a Wall plate 4 Upper runner 5 Lower liner 6 Fireproof coating 7 Rock wool material

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Akio Kohira 1-5-1, Otsuka, Inzai City, Chiba Pref. PA08 2E002 FA02 FB01 JA01 MA31 MA37

Claims (2)

[Claims] 1. A fire-resistant partition wall construction method comprising a partition wall provided directly below a steel beam provided with a fire-resistant coating, wherein a connecting member for vertically deforming a lower flange of the steel beam and an upper runner of the partition wall. A steel structure building characterized in that, even if the steel beam is heated to a high temperature due to a fire and generates a large bending, the connecting member follows and deforms so as not to exert an excessive load on the partition wall immediately below. Fire-prevention partition wall construction method. 2. An interval between the lower flange of the steel beam and the upper runner of the partition wall that is larger than the amount of deflection assumed at the time of the fire-resistant design temperature of the steel structure is secured. The method according to claim 1, wherein the lower flange and the upper runner of the partition wall are connected by a connecting member that deforms in a vertical direction.