CN1687254A - Single system and composite fire retardant coating for tunnel - Google Patents

Abstract

A method for manufacturing a single-system composite tunnel fireproof coating, its composition and ratio (relative parts by weight): binder (20.0-50.0) composed of redispersible latex powder and high-alumina cement, inorganic heat-insulating filler (55.0～85.0), additives (0.1～5.0). The use of an organic binder combined with a high-temperature-resistant inorganic binder improves the cohesiveness of the fireproof coating and increases the proportion of inorganic heat-insulating fillers in the fireproof coating composition; the use of an air-entraining agent enables the foaming process to It is carried out at low temperature, which avoids the damage to the strength of the coating caused by high-temperature foaming, and improves the fire resistance limit of the fireproof coating. At the same time, the fireproof coating has waterproof and sound insulation properties, and is easy to pack, transport and use. It is suitable for heat insulation and moisture retention of buildings, etc.

Description

A single-system composite tunnel fireproof coating

technical field

The invention belongs to the technical field of inorganic non-metallic materials and fire protection, and relates to a method for manufacturing a single-system compound fireproof coating for tunnels.

Background technique

During the construction of transportation channels, tunnels are favored by planners and builders for their advantages of convenience and low cost. However, in recent decades, due to the increasing traffic flow and improving road conditions, as well as the complexity of transporting items, the risk of fire in traffic tunnels has increased. And because the tunnel structure is complex and the environment is airtight, once a fire breaks out in a limited space, it is quite difficult to put out the fire, and the fire often lasts for a long time, which can easily cause casualties and heavy property losses.

The hazards caused by many traffic accidents at home and abroad have aroused great attention to the safety of tunnel fire safety in various countries, promoted the basic research on tunnel fire, and achieved certain results. At present, the more feasible and important fire prevention method is to spray the tunnel special fireproof coating on the concrete surface of the tunnel. Since the tunnel has been in a relatively humid environment for a long time, its fire burning has the characteristics of high temperature, and considering factors such as the firefighting work of firefighters can be carried out safely and quickly and the construction personnel's convenient construction, etc., the water resistance and fire resistance of the tunnel fireproof coating Higher requirements have been put forward for properties such as safety, non-toxicity, and workability, which have also become the focus of research by relevant scientific research units and production companies.

In the invention patent "Tunnel Fireproof Coating and Its Manufacturing Process" (Xiamen University, Patent Publication No. CN 1544556A), Dai Lizong and others proposed a split-type tunnel fireproof coating composed of inorganic materials and polymer emulsions. During the construction of the paint, the inorganic material part is soaked with a small amount of water, mixed with the polymer emulsion and then stirred for use; Publication number CN 1594452A) provides a kind of packaging type environment-friendly type tunnel fireproof coating, described coating is made up of the base material of packing separately and dispersant WM type pure acrylic flexible emulsion, earlier dispersant is stirred evenly at construction site, Then add the base material, and then use it after stirring evenly.

The manufacture of tunnel fireproof coatings reported above all adopts a two-component system, that is, a powder component and a liquid component. This polymeric dispersion is mixed with inorganic insulation materials to improve various properties of the fire protection coating composition. But with a two-component system, mixing on a harsh construction site often leads to many mistakes. In addition, due to the use of a two-component system, the moisture in the liquid component will directly affect the water consumption of the fire retardant coating, which will have a great impact on the strength, bonding strength, flexibility and fire resistance of the finished fire retardant coating. Simultaneously, because these two kinds of coatings all adopt sub-packaging, it has not only caused the increase of production, packaging and transportation costs, but also increased certain procedures for construction.

In addition, the foaming process of tunnel fireproof coatings in the above reports all occurs at high temperature, which belongs to the high temperature foaming process. At the same time, they will generate acid gas during the foaming process, which will chemically react with the alkaline substances in the fireproof coating such as Portland cement binder, which will drastically reduce the bonding of the fireproof coating at high temperature. strength.

Contents of the invention

The purpose of the present invention is to provide a single-system composite tunnel fire-proof coating with excellent comprehensive performance, no need for sub-packaging, and convenient construction for the defects of the two-component system tunnel fire-proof coating.

Another object of the present invention is to introduce a low-temperature foaming process so that the fireproof coating has stable material strength at both high and low temperatures.

The invention uses the air-entraining agent to produce uniform micropores when the dry material of the fireproof coating is mixed with water, that is, a low-temperature foaming process occurs, and avoids the reduction of the self-strength of the coating due to foaming reaction at high temperature.

The single-system composite tunnel fireproof coating of the present invention has components (relative parts by weight) consisting of binder, inorganic heat-insulating filler and auxiliary agent. The binder is 1.0-20.0 parts of redispersible latex powder, 15.0-50.0 parts of high-alumina cement; the inorganic thermal insulation filler is composed of 2.5-12.5 parts of expanded perlite, 18.0-39.5 parts of expanded vermiculite, sea foam Stone 4.0-23.0 parts, kaolin 2.0-11.0 parts, fibril 2.0-16.5 parts, talc 4.5-18.0 parts, glass floating beads 3.0-17.5 parts, aluminum hydroxide 3.0-28.0 parts, magnesium hydroxide 5.5-23.0 parts, mica 2.5-13.5 parts of powder, 3.5-8.5 parts of bentonite, 0.1-5.0 parts of high-efficiency superplasticizer, and 0.01-5.0 parts of air-entraining agent.

During the construction of the single-system composite tunnel fireproof coating of the present invention, the tunnel fireproof coating is formulated according to the ratio of dry material: water = 1.0: 0.6-0.9.

In the present invention, a one-component system is adopted to conveniently make the polymer fireproof coating have excellent performance. The use of redispersible polymer powder was successfully substituted for the polymeric dispersion, and the presence of the redispersible polymer powder did not affect the hydration of the cement. At the same time, it is equipped with high-temperature-resistant inorganic binder, inorganic heat-insulating filler and auxiliary agent, so that the present invention has the following advantages compared with previous products:

1. The single-component system tunnel fireproof coating reduces production, packaging, transportation costs and construction difficulty, and can be directly mixed with water at construction sites with severe conditions;

2. The redispersible latex powder has super surface hydrophilicity and cohesiveness. After adding a certain amount of redispersible latex powder, the amount of binder is reduced, so that the inorganic heat-insulating filler can be used in the fireproof coating composition The proportion of the coating can be increased, so that the fire-resistant limit of the fire-resistant coating is greatly improved. The coating thickness is 10mm, and the fire-resistant limit can reach more than 210min;

3. The high cohesiveness and surface hydrophilicity of the redispersible latex powder improve the bonding strength, tensile and bending strength of the finished fire retardant coating, so that the service life of the tunnel fire retardant coating in tunnels and underground projects has been improved. . Its bonding strength is 0.5MPa, and its compressive strength is 0.7MPa;

4. The flexibility of the redispersible latex powder endows the cement system with a certain deformation ability, which improves the weather resistance of the tunnel fireproof coating in the natural temperature difference, 40 times of cold and heat cycles, no cracking, no layering, no falling off;

5. The redispersibility of the redispersible latex powder in water improves the workability of the fireproof coating, which can be applied manually or mechanically;

6. The redispersible latex powder endows the waterproof performance of the tunnel fireproof coating, soaked in water for 30 days, no cracking, no layering, no falling off, far higher than the 24-hour water resistance requirement;

7. All components of the fire retardant coating are non-toxic and environmentally friendly materials, and the toxicity test has reached AQ-1;

8. The low-temperature foaming process is introduced to improve the strength of the fireproof coating at high temperature.

Detailed ways

Example 1:

Redispersible latex powder Vinnapas RE 526 Z 12 parts, high alumina cement 25 parts, expanded perlite 10 parts, expanded vermiculite 20 parts, sepiolite 4 parts, kaolin 8 parts, fibril 15 parts, talc 18 parts, glass 8 parts of floating beads, 6 parts of aluminum hydroxide, 9 parts of magnesium hydroxide, 3 parts of mica powder, 6 parts of bentonite, 0.1 part of superplasticizer, and 0.01 part of air-entraining agent. After fully mixing the dry ingredients, add 125 parts of water and mix well. The testing methods, items and testing results of the tunnel fireproof coating are shown in Table 1.

Example 2:

Redispersible latex powder Vinnapas RE 523 Z 14 parts, high alumina cement 23 parts, expanded perlite 6 parts, expanded vermiculite 25 parts, sepiolite 5 parts, kaolin 4 parts, fibril 8 parts, talc 5 parts, glass 6 parts of floating beads, 14 parts of aluminum hydroxide, 9 parts of magnesium hydroxide, 3 parts of mica powder, 4 parts of bentonite, 0.1 part of superplasticizer, and 0.02 part of air-entraining agent. After fully mixing the dry ingredients, add 120 parts of water and mix well. The testing methods, items and testing results of the tunnel fireproof coating are shown in Table 1.

Example 3:

Redispersible latex powder Vinnapas LL 5031 16 parts, high alumina cement 21 parts, expanded perlite 8 parts, expanded vermiculite 18 parts, sepiolite 5 parts, kaolin 3 parts, fibril 5 parts, talc 8 parts, glass drift 3 parts of beads, 6 parts of aluminum hydroxide, 12 parts of magnesium hydroxide, 3 parts of mica powder, 8 parts of bentonite, 0.1 part of superplasticizer, and 0.01 part of air-entraining agent. After fully mixing the dry ingredients, add 115 parts of water and mix well. The testing methods, items and testing results of the tunnel fireproof coating are shown in Table 1.

Example 4:

Redispersible latex powder Vinnapas LL 2055 18 parts, high alumina cement 20 parts, expanded perlite 10 parts, expanded vermiculite 25 parts, sepiolite 5 parts, kaolin 10 parts, fibril 10 parts, talc 5 parts, glass drift 8 parts of beads, 15 parts of aluminum hydroxide, 10 parts of magnesium hydroxide, 3 parts of mica powder, 7 parts of bentonite, 0.1 part of superplasticizer, and 0.02 part of air-entraining agent. After fully mixing the dry material, add 105 parts of water and mix well. The testing methods, items and testing results of the tunnel fireproof coating are shown in Table 1.

Example 5:

Redispersible latex powder Vinnapas RE 5044 N20 parts, high alumina cement 18 parts, expanded perlite 12 parts, expanded vermiculite 39 parts, sepiolite 4 parts, kaolin 2 parts, fibril 2 parts, talc 5 parts, glass drift 9 parts of beads, 15 parts of aluminum hydroxide, 10 parts of magnesium hydroxide, 5 parts of mica powder, 4 parts of bentonite, 0.1 part of superplasticizer, and 0.02 part of air-entraining agent. After fully mixing the dry material, add 105 parts of water and mix well. The testing methods, items and testing results of the tunnel fireproof coating are shown in Table 1.

Table 1 Technical performance indicators and test results of single-system composite tunnel fireproof coatings

Note: The testing standard is GA98-1995 "Prestressed Concrete Floor Fireproof Coatings"

Claims (6)

1, a kind of single system and composite fire retardant coating for tunnel is characterized by described coating and forms (relative weight umber): high-temperature agglomerant, inorganic thermal insulating filling, auxiliary agent.

2, a kind of single system and composite fire retardant coating for tunnel as claimed in claim 1 is characterized in that main binder is 15.0～50.0 parts of high-alumina cements, and additional adhesive is made up of for 1.0～20.0 parts redispersable latex powder.

3, a kind of single system and composite fire retardant coating for tunnel as claimed in claim 1 is characterized in that inorganic thermal insulating filling consists of 2.5～12.5 parts of pearlstones, 18.0～39.5 parts of expanded vermiculites, 4.0～23.0 parts of sepiolites, 2.0～11.0 parts of kaolin, 2.0～16.5 parts of protofibril, 4.5～18.0 parts in talcum, 3.0～17.5 parts of glass pearls, 3.0～28.0 parts in aluminium hydroxide, 5.5～23.0 parts of magnesium hydroxides, 2.5～13.5 parts of mica powders, 3.5～8.5 parts of wilkinites.

4, a kind of single system and composite fire retardant coating for tunnel as claimed in claim 1 is characterized in that auxiliary agent is 0.1～5.0 part of a high efficiency water reducing agent, 0.01～5.0 part of air entrapment agent.

5, air entrapment agent as claimed in claim 4 is characterized in that it is 6.0% that air entrapment agent is introduced the amount of air entrainment of frie retardant coating, belongs to the low-temp foaming process.

6, a kind of single system and composite fire retardant coating for tunnel as claimed in claim 1 is characterized by described single system and composite fire retardant coating for tunnel siccative: the ratio batching of water=1.0: 0.6～0.9.