JP3116267U - Asbestos-containing wall structure - Google Patents

Abstract

[PROBLEMS] To make harmful asbestos in existing buildings inexpensive, quickly detoxify, improve heat resistance, fire resistance and flame resistance, and safely dismantle and peel off at any time, simple in any case, Provided is an asbestos-containing wall structure that can be processed without eluting harmful fine powders in a safe and inexpensive manner.
The present invention relates to an existing asbestos sprayed and fixed to a wall surface base material, and a cement-mixed water-based coating agent whose cement mixing ratio is adjusted from the surface to spray the asbestos partially and entirely. An asbestos wall structure comprising a cured product obtained by drying and curing, and these are integrally bonded to the substrate with an adhesive strength having a required strength. Basically, a cement film with an appropriate thickness is formed on the surface of the cured product by blowing twice with an airless gun while changing the cement mixing ratio to form a safety wall. Depending on the blending and spraying method, timely dismantling is possible, and asbestos scattering problems do not occur at the time of subsequent dismantling.
[Selection] Figure 1

Description

  The present invention relates to an asbestos-containing wall structure. Specifically, by treating existing asbestos that is spray-fixed to the wall surface substrate with an aqueous coating agent mixed with an appropriate amount of cement, not only enables safe peeling after curing, but also permanent formation by the formation of a cement film. TECHNICAL FIELD The present invention relates to an asbestos-containing wall structure that enables even permanent storage.

  Asbestos (asbestos) is a fiber-like mineral that is loosened like cotton. It is inexpensive and excellent in heat retention and fire resistance, so it is fixed by spraying on the wall of the building.

  However, this asbestos is glassy and has a diameter that is nearly 1 / 500th that of hair, and there is a risk that powdered or mist-like asbestos will scatter from the asbestos after spraying, and countermeasures are desired. By the way, asbestos is firmly fixed to the wall surface when sprayed, but its surface deteriorates after several years, so to speak, it breaks down. When wind hits or hits the surface, fine dust with a length of 1 mm or less and a few microns in diameter is generated from the surface. When it enters the respiratory tract, it inhibits lung function, causing emphysema and cancer. To develop.

  Asbestos spraying work has already been banned, but there are concerns that a large amount of asbestos walls will remain at each facility nationwide, and that harmful fine powder will scatter from it. Therefore, if the asbestos adhered to the wall surface is peeled and removed, a large amount of harmful fine powder is generated at that time, and the disposal method becomes a problem. In addition, since the heat-resistant flame-resistant material is removed from the wall surface after peeling, research on how to do it is also necessary.

  Examples of conventional asbestos disposal methods include those disclosed in JP-A-1-188580, JP-A-2-48484, JP-A-3-229788, JP-B-4-69597, and the like.

  JP-A-1-188580 (osmotic fluid dustproofing agent for spraying asbestos dismantling) is a dustproofing agent used for asbestos disassembling work mainly composed of glycerin and a nonionic surfactant, and is compression-molded after dismantling. Can be disposed of. However, there remains a question as to whether or not the quality of compression molding after dismantling has been sufficiently secured, and dismantling is an absolute requirement.

  JP-A-2-48484 (asbestos dust generation prevention method) applies both silicate aqueous solution and polymer hydrosol mixed on the asbestos surface, or applied simultaneously without mixing, and dried and cured. In this way, a hard coating is formed on the asbestos surface to prevent dust scattering. However, even if the surface coating is made, the asbestos remains inside and the problem remains covered.

  Japanese Laid-Open Patent Publication No. 3-229788 (medicine composition for assembling and removing asbestos-containing materials) is a well-suited asbestos for making a highly permeable working agent including a surfactant represented by a special chemical formula and disassembling it. It has been shown that the kneading workability is good when it is necessary to cement the removed material. However, this is also an absolute condition for dismantling and is often difficult to apply.

Japanese Examined Patent Publication No. 4-69597 (asbestos scattering prevention method) firstly, asbestos is impregnated with a binder aqueous solution to form a coating layer, and a polymer cement is adhered to the entire surface, so that asbestos that has been easily scattered due to secular change is again applied. As well as integrating, asbestos and steel frame are secured firmly. However, there is a problem that it cannot be used in the case of dismantling because the process is surely two steps and it is planned to remain bonded to a base material such as a steel frame.
JP-A-1-188580, page 1 JP-A-2-48484, page 1 JP-A-3-299788, page 1 Japanese Examined Patent Publication No. 4-69597, page 1

  The present invention can use the harmful asbestos remaining on the walls of various buildings depending on whether it is to be dismantled or stored. In any case, harmful fine powder is eluted with a simple, safe and inexpensive method. An object of the present invention is to provide an asbestos-containing wall surface structure that can be processed without being done. The wall surface thus changed into a safety wall surface improves the performance as a fireproof fireproof wall even if left on the wall surface as it is, and does not generate harmful fine powder at the time of peeling and demolition, and even after peeling The object is to provide an asbestos-containing wall structure that can be safely processed without eluting harmful fine powders.

  The asbestos-containing wall structure of the present invention for solving the above-mentioned problems is obtained by spraying existing asbestos sprayed and fixed on a wall surface base material and a cement-mixed aqueous coating agent with a cement mixing ratio adjusted from the surface. The asbestos-containing wall structure comprising a cured product obtained by drying and curing the asbestos partially and entirely, and these are integrally bonded to the substrate with an adhesive strength having a required strength. is there.

  The wall base material is often concrete or steel frame, but the material is not limited. The same applies to the floor and the ceiling. The source of asbestos may be any of serpentinite, peridotite, and amphibole.

  In the present invention, a cement-mixed aqueous coating agent with a mixed cement ratio is sprayed from the surface of asbestos that has been sprayed. The amount of spraying is sufficient to sufficiently wet the entire asbestos. The cement-mixed aqueous coating agent can use SBR latex or the like as the main agent. It is water-based, can be mixed with cement, has good compatibility with asbestos fibers, is sufficiently wetted, encloses asbestos fibers by curing, and has a required adhesion to the substrate.

  As for wettability, asbestos fibers are fine and usually have the property of being wetted by water, so that most aqueous resins can be used. If necessary, an appropriate amount of a surfactant is added. By coating the asbestos with a cement-mixed aqueous coating agent, the entire asbestos located on the surface of the base material is gathered together while maintaining an appropriate gap by setting the concentration, adhesive strength, and spraying amount appropriately. At least the asbestos fine powder is not eluted from the surface, and the heat insulating property and the heat insulating property can be maintained. By increasing the adhesive strength with the substrate, it can be prevented from easily peeling. Thereby, it can modify | reform to a safe asbestos containing wall surface structure.

  The amount of cement included in the coating agent can also determine the surface coating thickness according to the amount. That is, when the blending amount is zero, a thick coating is not formed on the surface, but by increasing the blending amount, a cement coating having a required thickness can be formed on the surface accordingly.

  In addition, when it is desired to perform the dismantling operation immediately or eventually, if the cement-mixed aqueous coating agent is spray-cured and then peeled off in a timely manner, fine powder does not scatter in the stripping operation and can be safely disassembled. In this case, it is not necessary to bond the substrate excessively strongly. The adhesive strength with the substrate depends on the selection of the material of the water-based coating agent.

The most preferred example of the cement-mixed aqueous coating agent main agent is the aforementioned SBR latex. This is because it is widely used for cement modification as a cement admixture and has a proven track record and is safe. In the case of a rubber system, if the molecular weight is too high, the moisture permeability to asbestos may deteriorate. In order to solidify asbestos collectively, wetting, adhesion, and packaging must be considered. “Containability” indicates that asbestos fine powder does not scatter when it is crushed after curing, as long as it can be proved by actual tests. The amount of elution and scattering can be determined by collecting airborne substances on a glass plate and observing them with a microscope. Further, it may be dispersed in water, the water collected on a glass plate, and observed with a microscope. As a comparison object, untreated asbestos is crushed and collected on a glass plate by the same method and observed. The value is, for example, 100 to 10000 (cm) per 1 cm ² under a certain condition. In the present invention, this value can be made substantially zero.

As for the coating method, it is basically to blow twice while changing the cement mixing ratio, and it is standard to use airless coating for this spraying. In airless painting, when the coating agent is atomized, the paint is pressurized to a high pressure of 10 to 25 MPa (about 100 to 250 kgf / cm ² ) with a pressure pump, and the atomized paint is ejected from a nozzle tip having a small hole. It is a painting method. Airless coating is a technology that has already been established as a coating method suitable for thick film coating of high-viscosity paints for exterior walls of buildings, steel structures, plants, large tanks, ships, etc. due to its characteristics.

  Since the paint pressure (atomization pressure) is high, fine pulverization is promoted, and the coating work is performed at a speed several times faster than that of air spray. Further, since the amount of paint sprayed is large, thick film coating is possible. The coating efficiency at a practical level is 50 to 60% higher than that of 30 to 40% of air spray, so that the spraying of paint is reduced and environmental pollution due to spray mist is also relatively reduced. Although the skill level of spraying work is not so high, it is necessary to pay sufficient attention to the work safety associated with high-pressure injection.

  In airless coating, a high-pressure liquid is atomized and ejected from the pores, and examples of the spray pattern include a dot shape, a ring shape, and a fan shape. When considering spraying on the ceiling wall surface, in order to achieve sufficient penetration, spray it in a spot shape rather than spraying the entire surface, and spray the spray pattern toward the ceiling surface by moving it toward and away from the ceiling surface. It may be possible to apply penetration pressure to support penetration. As described above, since the spray pattern has a permeation subsidizing effect, improvement of the nozzle and the spraying method has been promoted so that this permeation subsidizing effect can be fully exhibited. Thereby, the penetration of about 2 cm can be naturally extended to about 5 cm.

  As described above, according to the present invention, asbestos remains on the base material by spraying the cement-mixed aqueous coating agent with the cement mixing ratio adjusted from the surface of the existing asbestos that is spray-fixed to the wall surface base material. Since the asbestos is cured, it is possible to obtain a cured product in which the asbestos is partially and entirely surrounded and integrated. In addition, the water content of mortar-mixed water-based coating agents can be freely adjusted, and since it can penetrate from asbestos to the base material, especially the ceiling surface, in addition to capillary action, it can penetrate from asbestos to the base material, especially the ceiling surface. The work can be safely completed while fixing the asbestos that is easily scattered, and the asbestos and the base material can be securely bonded.

  The asbestos-containing wall structure thus configured is a safe wall structure that does not scatter or elute asbestos fine powder and has improved heat retention, heat insulation, fire resistance, and the like.

  In addition, since it can be a cured product that can prevent asbestos scattering immediately after curing or after curing, asbestos fine powder is not scattered at the time of disassembly and peeling, and disassembly and peeling work is performed at the required time. It can be done safely.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, the best mode for carrying out the invention will be described with reference to the accompanying drawings. FIG. 1 is a sectional explanatory view showing an asbestos-containing wall structure according to the present invention.

  As shown in FIG. 1, a cement-mixed aqueous coating agent 3 containing SBR latex as a main ingredient is sprayed from the surface of asbestos 2 fixed by spraying to a wall surface substrate 1, and the asbestos 2 is partially and The asbestos-containing wall structure 5 having a partially cured product 4 is formed by being cured by the aqueous coating agent 3 in a totally enclosed form.

  Examples of the cement-mixed aqueous coating agent mainly composed of SBR latex include those obtained by blending an appropriate amount of cement with Tomak Super (trade name) of Etec Co., Ltd. and Sun Creat 225 (trade name) of Sun Engineering Co., Ltd. The basic material was developed as a surface active admixture for cement using nanocarbon manufactured by Kao Corporation. Total solid content 45.0%, 9.5PH, particle size 50mPas, apparent A milky white liquid with a specific gravity of 1, mechanically safe, and highly stable against cement. Add appropriate amount of water and cement to this and spray with airless gun.

  The construction is basically blown twice, and the first time, the cement-mixed aqueous coating agent 3 (mixed with a ratio of admixture 1, cement 1, water 0.6) adheres to the base material 1 in the form of cotton. Blow well onto asbestos 2 so that it is moistened to the depth.

  When the asbestos 2 is sufficiently wet and spraying is completed, the asbestos 2 is semi-dried in about 2 hours. Semi-drying means that sufficient penetration has taken place and that excess moisture has been dissipated. There is no need for complete curing (solidification). There is no need for the inner layer and the outer layer to have a two-layer structure using different coating materials. The second time, a cement-mixed aqueous coating agent (mixed at a ratio of admixture 1 and cement 1) is sprayed. The whole is completely cured after a few days. Since the same material is different only in the amount of water, the workability and the mutual adhesiveness are exceptionally good, unlike the two-time coating operation by changing the material. Since cement particles are difficult to penetrate inside, most of them remain as a coating on the surface.

 Partial enlarged views after curing are indicated by EX1, EX2, and EX3. EX1 is a surface magnified about 10 times. EX2 is enlarged about 500 times to show the internal situation. EX3 is magnified about 10 times and shows the state of adhesion with the base material 1.

  As shown in the enlarged view EX1, a coating portion 6 formed by cement hardening is formed on the surface, and the asbestos 2 is collectively cured leaving an internal cavity portion 7.

  As shown in the enlarged view EX2, inside, the fibers of asbestos 2 are grouped by the mutual adhesion of the resin surrounding them, and even if they are partially broken, they are not scattered or eluted in the asbestos fiber unit. It is in a state.

  As shown in the enlarged view EX3, the structure 5 is bonded to the substrate 1, and the structure 5 is not easily peeled off from the substrate 1. The degree of adhesion depends on the adhesive strength of the main component of the cement-mixed aqueous coating agent 3.

  It is preferable that the asbestos 2 is sufficiently wetted with the cement-mixed aqueous coating agent 3. Since asbestos itself has a property of sucking water by 1 to 2 cm by capillary action, it is sufficient to spray from the surface on the vertical plane and around the pipe. However, it is difficult to penetrate 2 cm or more on the ceiling surface. Although it is possible to increase the penetrability by containing a surfactant up to a depth of about 5 cm, an airless coating machine is still optimal in order to wet the surface of the substrate 1 by sufficient permeation. Since the fine powder atomized by the special nozzle comes out, physical wetting between the fibers can be expected. Do not blow quickly, but let it wet and penetrate thoroughly over time.

  Asbestos is finer than expected and is not without the possibility of flying in the air. Therefore, it must be done safely with a safety mask during work.

  As described above, the asbestos-containing wall structure 5 of the present invention is formed on the surface of the substrate 1. Since the asbestos-containing wall surface structure 5 has a shape in which the periphery of the asbestos 2 is wrapped as a partially cured product 4, the fine powder of the asbestos 2 is not scattered and eluted, and is safe.

  Moreover, since the asbestos-containing wall structure 5 is peeled in the dismantling and peeling, the fine powder of asbestos 2 is not scattered during the peeling work, and the dismantling work at an arbitrary time can be performed safely. For the purpose of peeling, the aqueous coating agent 3 can be sprayed and cured in advance. In this case, the amount of cement blended is reduced, the amount of water is increased, and blowing is performed once or twice.

  Since the asbestos after dismantling is the asbestos-containing wall structure 5, it can be used as it is as a road laying material or the like as a resource recycling material. In this case, in order to achieve long-term stability, a coating agent that does not cause long-term deterioration is selected.

  The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention and can be implemented in various aspects.

It is sectional drawing which shows the asbestos containing wall surface structure which concerns on one Embodiment of this invention, and its partially expanded explanatory drawing. The magnifications of EX1 and EX3 are 10 times, and EX2 is 500 times.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Wall base material 2 Asbestos 3 Aqueous coating agent 4 Partially hardened | cured material 5 Asbestos containing wall structure 6 Film part 7 Cavity part

Claims (4)

 The existing asbestos sprayed and fixed to the wall substrate and the cement-mixed aqueous coating agent with the cement mixing ratio adjusted from its surface are sprayed and dried and hardened in a partially and totally enclosed manner. An asbestos-containing wall structure comprising: a cured product that is integrally bonded to the substrate with an adhesive force having a required strength.   2. The asbestos-containing wall structure according to claim 1, wherein the adhesive force is adjusted to be weak so as to be peeled off after curing, or is strongly adjusted so as to be stably fixed.   2. The adhesive force according to claim 1, wherein the adhesive force is weak with respect to the base material, and the cured product is easily peeled off from the base material and safely removed after the curing treatment. Asbestos-containing wall structure. The asbestos-containing wall structure according to any one of claims 1 to 3, wherein the aqueous coating agent contains a cement admixture whose main component is SBR latex.

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