JPH0520375B2

JPH0520375B2 -

Info

Publication number: JPH0520375B2
Application number: JP59221490A
Authority: JP
Inventors: Toshio Kumagai
Original assignee: Shimizu Construction Co Ltd
Current assignee: Shimizu Construction Co Ltd
Priority date: 1984-10-22
Filing date: 1984-10-22
Publication date: 1993-03-19
Also published as: JPS61101475A

Description

[Detailed description of the invention]

〔産業上の利用分野〕この発明は鉄骨構造の建築物などにおいて、鉄
骨等に被覆して耐火構造とするための耐火被覆材
に関する。〔従来の技術〕従来、このような用途の耐火被覆材としては、
吹付岩綿がもつぱら使用されている。この吹付岩
綿は岩綿に少量のセメントを混入した半湿式材料
であり、これを鉄骨表面等に吹き付けて耐火被覆
とするものである。〔発明が解決しようとする問題点〕しかしながら、この半湿式吹付岩綿による耐火
被覆施工にあつては、次のような問題点があり、
その解決が望まれている。耐火被覆の強度が低くて脆く、欠落したり、
損傷を受けやすい。施工に手間を要する。すなわち、耐火被覆に
所定の密度を確保するため、吹き付け後、コテ
押え必要であり、また表面のケバ立ち防止、硬
度確保のため、吹き付け後ペースト吹きが必要
がある。所定の耐火性能を得るための吹き付け厚さが
大きく、必要材料量が多くなり、施工管理上不
利であり、また柱、梁の仕上り寸法が大きくな
り、室内空間が小さくなる。吹き付けに際し、粉塵が多量に発生し、作業
環境が劣悪である。〔問題点を解決するための手段〕そこで、この発明においては、このような半湿
式の吹付岩綿による耐火被覆材を根本的に見直
し、低温度伝導性無機材料高吸熱性無機材料膨脹性無機材料耐熱向上無機材料常温粘結材料高温粘結材料を組み合せ、かつ高温粘結材料に耐水性向上含浸
被覆および耐炭酸化被覆の粒状水ガラスを用いる
ことにより上記問題点を解決するようにした。この発明の耐火被覆材は、高温粘性結材料とし
て耐水性向上含浸被覆および耐炭酸化被覆を形成
した粒状水ガラスを配合するとともに、その配合
組成を低温度伝導性無機材料 10〜20重量％高吸熱性無機材料 10〜30重量％膨脹性無機材料５〜25重量％耐熱向上無機材料５〜15重量％常温粘結材料５〜20重量％高温粘結材料 15〜40重量％としたものである。上記低温度伝導性無機材料としては、次式で定
義される温度伝導率ａが0.001m²／hr以下の無機
材料が用いられる。ａ＝λ／cp ａ：温度伝導率（m²／hr） λ：熱伝導率（kcal／ｍ・hr・℃）ｐ：密度（Kg／m³）ｃ：比熱（kcal／Kg・℃）具体的には、粘土、石膏、膨脹真珠岩、膨脹ひ
る石、岩綿、ケイソウ土などが用いられる。この
材料は熱伝導量が小さく、火炎で加熱されたと
き、鉄骨等に熱が伝わる時間を引き延ばし、結果
的に耐火性を発揮する。この材料の配合量は、耐
火被覆材に対して10〜20重量％とされる。10重量
％未満では、遮熱性が不十分で鉄骨の温度上昇が
大となつて、不都合であり、20重量％を越えると
造粒形状のものが多いためボソボソ状になりモル
タルの圧送性や塗付け性が悪くなつて不都合であ
る。また、高吸熱性無機材料としては、吸熱量が
50cal／ｇ以上の材料が使用され、具体的には、
主に結合水や吸蔵水を多く含むグラフアイト、ハ
イジライト、塩化マグネシウム、硼砂、ひる石原
鉱石などが用いられる。この材料は、熱を受けた
際、これら結合水、吸蔵水が蒸発し、この蒸発潜
熱によつて熱を奪い、結果的に耐火性を示すもの
である。この高吸熱性無機材料の配合量は10〜30
重量％とされる。10重量％未満では、吸熱量が小
となり温度上昇が大となつて不都合であり、30重
量％を越えるとこの成分は以下に述べる膨脹成分
と重なる所があり、膨脹量が過大となり安定した
形状を保つことが難しくなり、やはり不都合であ
る。また、膨脹性無機材料としては、加熱される
と、それ自体が膨脹して多孔質化し、高い断熱性
を発揮して耐火性を示すもので、例えばグラフア
イト、ひる石原鉱石、水ガラスなどの膨脹率が50
％以上のものが用いられる。この材料の配合量は
全体の５〜25重量％とされる。５重量％未満では
膨脹量が不足し耐火性がえられず不都合であり、
25重量％を越えると、膨脹量が過大となり安定し
た形状を保つことが難しくなり不都合である。耐熱向上無機材料は、上記種々の材料が長く高
温に曝されると、徐々に劣化して保形性を失い、
崩壊するのを防止し、より高度の耐火性を確保す
るためのもので、具体的には、アモルフアスシリ
カ、消石灰のうち一種あるいは二種が使用され
る。この材料の配合量は５〜15重量％とされる。
５重量％未満では耐火安定性が劣るものとなつて
不都合であり、15重量％を越えると耐火断熱性が
低下して不都合である。また、常温粘結材料は、上記各材料を相互に固
結して耐火被覆材として一体に固めるもので、特
に被覆施工時および被覆施工後の平常時に固結作
用を発現するもので、石膏や各種セメントなどの
水硬性材料が使用される。この常温粘結材の配合
量は全体の５〜20％とされる。５重量％未満では
強度的に不足し、欠けやいたみが生じ易く不都合
であり、20重量％を越えると強度が大きくなり過
ぎ膨脹反応が抑制されてしまうこととなつて不都
合である。さらに、高温粘結材料は、特に加熱された際に
固結作用を発揮し、高温下での保形性を確保し、
耐火性を向上せしめるものである。この高温粘結
材料には、耐水性向上含浸被覆および耐炭酸化被
覆が形成された粒径２〜５mmの粒状水ガラスが用
いられる。この粒状水ガラスは常温では何んら固
結作用を示さないが、加熱されると、約200〜300
℃で溶融しはじめるとともに発泡し、各材料を固
結するもので、約800℃まで固結作用が維持され
る。特に、ここでは耐水性向上含浸被覆と耐炭酸
化被覆とで被覆された粒状水ガラスを用いている
ので、施工中での水かかりによつて水ガラスが溶
解することが防止され、かつ施工後の空気中の炭
酸ガスによる水ガラスの炭酸化が防止され、これ
により長期にわたつて粒状水ガラスの発泡性が保
たれ、結果的に高温粘結材料としての耐久性が向
上する。上記耐水被覆としては、ステアリン酸、ステア
リン酸カルシウムなどの撥水剤を含浸させたもの
が、また耐炭酸化被覆としてはクロロプレンなど
のゴムやアクリル樹脂などの樹脂等の高分子材を
厚さ0.5〜１mmに被覆したものが使用される。被
覆構成は、粒状水ガラス表面にまず耐水性向上含
浸被覆が設けられ、この上に耐炭酸化被覆が設け
られる。この高温粘結材料の配合量は、全体の15〜40重
量％とされる。15重量％未満であれば膨脹層をう
まく保持できなくなりとなつて不都合であり、ま
た40重量％を越えるとコスト面で採算が合わなく
なるなどの不都合を来す。以上の各種材料は、その所定量が配合されたう
え、配合量100重量部に対して水40〜50重量部が
加えられて混練される。混練には通常のモルタル
ミキサー等が利用できる。この混練物は、その性
状が通常のモルタルと同様であり、モルタル吹付
機などの吹付装置によつて、組立済みの鉄骨表面
等に吹き付けることによつて耐火被覆とされる。
吹き付けには、作業環境を考慮して吹付けロボツ
トを用いることもでき、勿論コテ塗りで被覆する
ことも可能である。鉄骨表面への付着性は良好で
あり、改めてコテ押えなどは不要であり、吹き付
けられた被覆材は通常１日で硬化し、強固な耐火
被覆となる。〔作用〕このような耐火被覆材にあつては、高温粘結材
料に耐水被覆と耐炭酸化被覆とを有する粒状水ガ
ラスを用いているので、水ガラスの高温での固結
作用が長期（10年以上）にわたつて保持される。
すなわち、通常の水ガラスでは施工中の水かかり
によつて水ガラスが溶解流出したり、あるいは施
工後空気中の炭酸ガスと反応して次式のように水
ガラスが炭酸化して発泡性が低下したりするが、 Na₂SiO₃＋CO₂→Na₂CO₂＋SiO₂ この発明において用いられる粒状水ガラスは耐
水被覆と耐炭酸化被覆が施されているので、この
ような不都合を来すことがない。また、硬化した耐火被覆はその強度が著るしく
高い。次の第１表は、この耐火被覆と従来の半湿
式および湿式の吹付岩綿との曲げ強度および圧縮
強度を示したものである。 [Industrial Field of Application] The present invention relates to a fire-resistant coating material for coating a steel frame or the like to provide a fire-resistant structure in a steel-frame building or the like. [Conventional technology] Conventionally, fireproof coating materials for such uses include:
Sprayed rock wool is mostly used. This sprayed rock wool is a semi-wet material made by mixing rock wool with a small amount of cement, and is sprayed onto the surfaces of steel frames to create a fireproof coating. [Problems to be solved by the invention] However, there are the following problems with this semi-wet sprayed rock wool fireproof coating construction.
A solution is desired. The strength of the fireproof coating is low and brittle, and it may be missing or missing.
susceptible to damage. Construction takes time. That is, in order to ensure a predetermined density in the fireproof coating, it is necessary to press down with a trowel after spraying, and in order to prevent the surface from becoming fluffy and to ensure hardness, it is necessary to spray the paste after spraying. The spraying thickness is large to obtain a predetermined fire resistance, which increases the amount of material required, which is disadvantageous in terms of construction management, and also increases the finished dimensions of columns and beams, reducing indoor space. During spraying, a large amount of dust is generated and the working environment is poor. [Means for Solving the Problems] Therefore, in this invention, we fundamentally reviewed the fireproof coating material made of semi-wet sprayed rock wool, and developed the following materials: low-temperature conductive inorganic material, high endothermic inorganic material, and expandable inorganic material. The above-mentioned problems were solved by combining a heat-resistant inorganic material, a room-temperature caking material, and a high-temperature caking material, and using granular water glass with a water-resistance-improving impregnated coating and a carbonation-resistant coating as the high-temperature caking material. The fire-resistant coating material of the present invention contains granular water glass formed with a water resistance-enhancing impregnated coating and a carbonation-resistant coating as a high-temperature viscosity binding material, and the blended composition is a low-temperature conductive inorganic material of 10 to 20% by weight. Endothermic inorganic material 10 to 30% by weight Expandable inorganic material 5 to 25% by weight Heat resistance improving inorganic material 5 to 15% by weight Room temperature caking material 5 to 20% by weight High temperature caking material 15 to 40% by weight . As the low temperature conductive inorganic material, an inorganic material having a temperature conductivity a defined by the following formula of 0.001 m ² /hr or less is used. a=λ/cp a: Temperature conductivity (m ² /hr) λ: Thermal conductivity (kcal/m・hr・℃) p: Density (Kg/m ³ ) c: Specific heat (kcal/Kg・℃) Specific Typically, clay, gypsum, expanded nacre, expanded vermiculite, rock wool, diatomaceous earth, etc. are used. This material has a low thermal conductivity, and when heated by flame, it prolongs the time it takes for the heat to be transferred to the steel frame, etc., resulting in fire resistance. The blending amount of this material is 10 to 20% by weight based on the fireproof coating material. If it is less than 10% by weight, the heat shielding properties will be insufficient and the temperature of the steel frame will rise significantly, which is disadvantageous. If it exceeds 20% by weight, many of the particles will be in the form of granules, which will become crumbly and affect the pumpability of the mortar and the coating. This is inconvenient as it makes it difficult to attach. In addition, as a highly endothermic inorganic material, the amount of heat absorbed is
Materials with a content of 50 cal/g or more are used, specifically,
Mainly used are graphite, hygilite, magnesium chloride, borax, and vermiculite raw ore, which contain a large amount of bound water and occluded water. When this material receives heat, the bound water and occluded water evaporate, and the latent heat of evaporation removes heat, resulting in fire resistance. The blending amount of this highly endothermic inorganic material is 10 to 30
% by weight. If it is less than 10% by weight, the amount of heat absorbed is small and the temperature rise is large, which is disadvantageous. If it exceeds 30% by weight, this component overlaps with the expansion component described below, resulting in an excessive amount of expansion and a stable shape. It becomes difficult to maintain this condition, which is still inconvenient. In addition, expandable inorganic materials include those that expand and become porous when heated, exhibiting high heat insulation properties and exhibiting fire resistance, such as graphite, vermiculite ore, and water glass. Expansion rate is 50
% or more is used. The blending amount of this material is 5 to 25% by weight of the total. If it is less than 5% by weight, the expansion amount is insufficient and fire resistance cannot be obtained, which is disadvantageous.
If it exceeds 25% by weight, the amount of expansion becomes excessive and it becomes difficult to maintain a stable shape, which is disadvantageous. When the above-mentioned various materials are exposed to high temperatures for a long time, heat-resistant inorganic materials gradually deteriorate and lose their shape retention.
This is to prevent collapse and ensure a higher degree of fire resistance. Specifically, one or two of amorphous silica and slaked lime are used. The blending amount of this material is 5 to 15% by weight.
If it is less than 5% by weight, the fire resistance stability will be poor, which is disadvantageous, and if it exceeds 15 weight%, the fire resistance and heat insulation properties will be reduced, which is disadvantageous. In addition, room-temperature caking materials are materials that solidify the above-mentioned materials together to form a fire-resistant coating material, and exhibit a caking effect particularly during coating construction and at normal times after coating construction, such as plaster or Hydraulic materials such as various cements are used. The blending amount of this room temperature caking agent is 5 to 20% of the total. If it is less than 5% by weight, the strength will be insufficient and chipping or damage will easily occur, which is disadvantageous. If it exceeds 20% by weight, the strength will be too high and the expansion reaction will be suppressed, which is disadvantageous. Furthermore, high-temperature caking materials exhibit a caking effect especially when heated, ensuring shape retention at high temperatures,
This improves fire resistance. This high-temperature caking material uses granular water glass with a particle size of 2 to 5 mm, on which a water resistance-enhancing impregnated coating and a carbonation-resistant coating are formed. This granular water glass does not show any solidifying effect at room temperature, but when heated, it has a hardening effect of about 200 to 300
It begins to melt at ℃ and foams to solidify each material, and its solidifying effect is maintained up to approximately 800℃. In particular, since granular water glass coated with a water-resistance-improving impregnated coating and a carbonation-resistant coating is used here, the water glass is prevented from dissolving due to water splashing during construction, and after construction. Carbonation of the water glass due to carbon dioxide gas in the air is prevented, thereby maintaining the foamability of the granular water glass over a long period of time, resulting in improved durability as a high temperature caking material. The above-mentioned water-resistant coating is impregnated with a water repellent such as stearic acid or calcium stearate, and the carbonation-resistant coating is made of a polymeric material such as rubber such as chloroprene or resin such as acrylic resin with a thickness of 0.5~ A coating coated with a thickness of 1 mm is used. In the coating structure, a water resistance-enhancing impregnated coating is first provided on the surface of the granular water glass, and then a carbonation-resistant coating is provided thereon. The content of this high temperature caking material is 15 to 40% by weight of the total. If it is less than 15% by weight, it is inconvenient that the expanded layer cannot be held well, and if it exceeds 40% by weight, it is not profitable in terms of cost. The above-mentioned various materials are blended in predetermined amounts, and then 40 to 50 parts by weight of water is added to 100 parts by weight of the blended amount and kneaded. A normal mortar mixer or the like can be used for kneading. This kneaded material has properties similar to ordinary mortar, and is sprayed onto the surface of an assembled steel frame using a spraying device such as a mortar sprayer to form a fireproof coating.
For spraying, a spraying robot may be used in consideration of the work environment, and of course it is also possible to coat with a trowel. It has good adhesion to the steel surface, and there is no need to use a trowel to hold it down, and the sprayed coating usually hardens within one day, forming a strong fireproof coating. [Function] In the case of such fire-resistant coating materials, granular water glass having a water-resistant coating and a carbonation-resistant coating is used as the high-temperature caking material, so the caking effect of water glass at high temperatures is long-term ( 10 years or more).
In other words, with ordinary water glass, the water glass dissolves and flows out due to water splashing during construction, or reacts with carbon dioxide gas in the air after construction, causing the water glass to carbonate as shown in the following equation, reducing foaming properties. However, Na ₂ SiO ₃ + CO ₂ → Na ₂ CO ₂ + SiO _2Since the granular water glass used in this invention is coated with a water-resistant coating and a carbonation-resistant coating, such inconveniences will not occur. do not have. Also, the strength of the cured fireproof coating is significantly higher. Table 1 below shows the flexural and compressive strengths of this fireproof coating and conventional semi-wet and wet blown rock wool.

〔Effect of the invention〕

以上説明したように、この発明の耐火被覆材に
よれば、高温粘結材に耐水性向上含浸被覆と耐炭
酸化被覆を形成した粒状水ガラスを用いているの
で、高温粘結材の固結作用が長期にわたつて維持
され、信頼性の高い耐火被覆が得られる。また、
温度伝導率の小さい材料、吸熱量の大きい材料、
膨脹性のある材料をバランスよく配合したので、
耐火性がよく、従来の吹付岩綿に比べて被覆厚さ
を半減することができ、材料使用量を少なくでき
る。さらに、被覆の強度が従来のものに比べて非
常に大きいので、組み立て前の鉄骨に被覆する先
付け工法が取れ、耐火被覆施工の能率化、安全性
向上等が達成できる。またさらに、施工時粉塵の
発生がなく、作業環境が良好で、かつ作業も吹付
けのみでよく被覆処理作業の能率が高くなるなど
の効果を得ることができる。 As explained above, according to the fireproof coating material of the present invention, since the granular water glass in which the high-temperature caking material is coated with a water-resistance-improving impregnation coating and the carbonation-resistant coating is used, the high-temperature caking material is solidified. The effect is maintained over a long period of time, resulting in a highly reliable fireproof coating. Also,
Materials with low temperature conductivity, materials with high heat absorption,
With a well-balanced combination of expansive materials,
It has good fire resistance and can reduce the coating thickness by half compared to conventional sprayed rock wool, reducing the amount of material used. Furthermore, since the strength of the coating is much greater than that of conventional coatings, it is possible to apply the coating to the steel frame before assembly, making it possible to improve the efficiency and safety of fireproof coating construction. Furthermore, there is no generation of dust during construction, the work environment is favorable, and the work can be done only by spraying, and the efficiency of the coating treatment work can be improved.

Claims

[Claims] 1. 10 to 20% by weight of a low temperature conductive inorganic material with a temperature conductivity of 0.001 m ² /hr or less, and a highly endothermic inorganic material with an endothermic amount of 50 cal/g or more.
10 to 30% by weight, 5 to 25% by weight of an expandable inorganic material with an expansion rate of 50% or more, 5 to 15% by weight of an inorganic material for improving heat resistance consisting of one or two of amorphous silica and slaked lime, gypsum, 5 to 20% by weight of a room-temperature caking material made of a hydraulic material such as cement, and 15 to 20% by weight of a high-temperature caking material made of granular water glass with an impregnated coating for improving water resistance and a carbonation-resistant coating.
A fireproof covering material containing 40% by weight.