JPS6350501B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of applying an inorganic expandable fire-resistant coating to a steel material such as a section steel to provide a fire-resistant coating to a structural steel material.

Fireproof coatings for structural steel materials (hereinafter referred to as steel materials) have changed from pasting formed asbestos plates to spraying with rock wool mortar, vermiculite plaster, etc. Most of the spraying of this fire-resistant coating is done at construction sites, so there is a problem with dust scattering into the neighborhood during construction, and even if it is installed, it can not only fall off due to rain or seismic motion, but also be prone to fires. When heated, it tends to crack, peel, etc., and further improvements have been required for fireproof coating of steel frames etc. for many years.

This invention was conceived in view of the above-mentioned circumstances, and its purpose is to eliminate the need for spraying on-site, to be able to be constructed at a factory, and to prevent fire-resistant coatings applied to steel materials from being exposed to rain or rain. The object of the present invention is to use an inorganic expandable fireproof coating to create a fireproof coating that will not fall off even during seismic motion and will not peel off even when expanded at high temperatures.

The present invention will be explained in detail below using illustrated examples.

1 is a shaped steel material used for steel beams, steel columns, etc. First, the surface of the steel material 1 is cleaned and prepared, and then an anti-lifting layer 2 made of polymer cement paste mixed with acrylic emulsion is applied. Next, on top of the anti-lifting layer 2, an inorganic intumescent fireproof coating material made of vermiculite, calcium silicate, etc. and added with a fireproofing agent and other auxiliary agents is applied to a predetermined thickness. The fireproof coating layer 3 is formed by applying by spraying or troweling. The construction of the fireproof coating layer 3 is carried out in two steps, and when the inorganic expandable fireproof coating material has been applied to a certain extent, the entire fireproof coating layer 3a that has been formed primarily is covered with a wire mesh 4. Tie only the walnuts and the wrap part. Wrapping with the wire mesh 4 can be done arbitrarily depending on the shape of the steel material, but in the case of shaped steel, it is easier to wrap it in the upper and lower parts as shown.

After the wire mesh 4 has been attached, an inorganic expandable fireproof coating material is further applied to form a fireproof coating layer 3b on the front side.

In the fireproof coating structure constructed as described above, the fireproof coating layer 3 expands upon heating.
During this expansion, if the fireproof coating layer is simply coated with an inorganic expandable fireproofing material, the skin will be torn and the internal fireproof coating will fall off, but the wire mesh 4 will be removed from the fireproof coating layer 3.
If the fireproof coating layer 3b on the front side falls off, it will not reach the fireproof coating layer 3a on the inside, and the fireproof coating will be maintained for a long time.

Furthermore, when the fireproof coating layer 3 is applied directly to the steel material 1, the expansion of the fireproof material causes the steel material 1 and the fireproof coating layer 3 to
However, when polymer cement paste is applied as the anti-lifting layer 2,
The polymer cement paste adheres tightly on both sides between the steel surface and the coating material, does not trap air bubbles, and has an adhesive force that prevents lifting and explosions, and the inner fireproof coating layer 3a is not affected by external temperature. In contact with the steel material 1, the insulation properties are maintained until the end.

As described above, this invention applies a lifting prevention layer made of a polymer cement paste to a steel material, then a fireproof coating made of an inorganic intumescent fireproof coating material, and a wire mesh inside the fireproof coating to prevent the fireproof coating from falling off. Because the insulation is made of asbestos, it has better insulation properties than plasters such as asbestos molded boards or rock wool mortar.

In addition, since the construction can be done in a factory, various problems associated with on-site construction can be solved, and the fireproof coating layer can be thinner compared to the current spraying methods, which can reduce costs. .

Furthermore, since the process is simple and fireproof coating can be applied to every detail, it is not limited to specific shapes of structural steel materials, and it also has a rust-preventing effect, so it can be applied to fireproof coatings such as steel frames and steel towers. It has the following features.

[Brief explanation of the drawing]

The drawing is a perspective view of a fireproof coating structure constructed using the fireproof coating method according to the present invention. DESCRIPTION OF SYMBOLS 1... Steel material, 2... Lifting prevention layer, 3... Fireproof coating, 3a... Inner fireproof coating layer, 3b... Outer fireproof coating layer, 4... Wire mesh.

Claims (1)

[Claims] 1. In a fireproof coating method in which a structural steel material such as a section steel is coated with an inorganic expandable fireproof coating material and a wire mesh is provided within the fireproof coating to prevent expansion and falling off, the surface of the structural steel material is A fireproof coating method for structural steel materials, characterized in that a polymer cement paste is applied as a layer to prevent the fireproof coating from lifting up due to heating and expansion.