JPS5912840B2 - How to block water leakage from construction materials - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a construction method for blocking water leakage from walls of concrete and other construction material frames constituting tunnels, underground passages, and the like.

Water often leaks from the walls at cracks and joints in the concrete and brickwork structures that make up tunnels, underpasses, and basements.

This water leakage not only impairs the aesthetic appearance of the inner walls of tunnels and underpasses, but also can form icicles in railway tunnels during the winter, and the icicles may come into contact with overhead wires, causing power outages. .

Conventionally, as a construction method to block water leakage from concrete and other construction material frames as mentioned above, if the leakage is minor, adhesives such as polyurethane, epoxy, polyvinyl leadate, or polyacrylic ester are used at the leakage point. A method of applying adhesives or a mixture of these adhesives and cement mortar has been adopted.

In addition, if there is a large amount of water leakage, drill a hole at the leakage point,
A method of filling the perforation by injecting the above-mentioned adhesive or adhesive-cement mortar mixture into the perforation is employed.

However, with such conventional construction methods, the period until water starts leaking again from the construction site after construction is short, and therefore,
It was almost impossible to block water leaks semi-permanently.

The purpose of the present invention is to effectively block water leakage from concrete and other construction material frames constituting underground passages, tunnels, etc., particularly in areas where the discharge pressure of leakage water is high and the amount of water leakage is large, and to provide a long-lasting water leakage prevention effect after construction. The purpose is to provide a construction method that lasts semi-permanently over a period of time.

The method of blocking water leakage from a construction material frame according to the present invention is as follows:
(1) A through hole is drilled in a part of the water leakage point in a crack or a connection part of the construction material frame, or in a place near the water leakage point, and (2) a high molecular weight atactic polypropylene as a basic component is drilled through the through hole. The aqueous liquid or an aqueous liquid mixed with cement begins to be injected, and (3) the injected aqueous liquid is diffused onto the back side of the construction material frame, and this diffused aqueous liquid is used to reduce the earth pressure on the back side of the construction material frame. The above press-fitting is continued until the water pressure causes the base component to seep into the inner wall surface of the structure through cracks in the structure or minute gaps in the connection parts. The method is characterized in that a mixture of an aqueous liquid and early-strengthening cement is press-fitted and hardened to close the through holes.

Hereinafter, the construction method according to the present invention will be explained with reference to the accompanying drawings.

The attached drawing is a sectional view showing the state after applying the water leakage blocking method to a construction material frame having cracks.

Water leakage points, i.e., cracks 2, 2', in the construction material frame 1, such as concrete or brickwork, that constitutes tunnels, underground passages, etc.
Alternatively, a through hole 4 is first drilled in a part of the connection part (not shown) or in a position close to the water leakage point.

The number of through holes 4 varies depending on the number of water leakage points, but it is sufficient to drill one through hole 4-' per concrete surface 1d to 4d where water leakage is usually seen.

Next, through the through hole 4, an aqueous adhesive liquid 5 containing high molecular weight atactic polypropylene as a basic component or an aqueous adhesive liquid in which cement is mixed is press-fitted (the aqueous adhesive liquid to be used will be described later).

The press-fitted aqueous adhesive liquid 5 spreads over the back side of the construction material frame 1 centering around the outlet end of the through hole 4, and is diluted by the water present on the back side of the side body.

As the press-fitting continues, the diffused and diluted aqueous adhesive liquid 5 infiltrates into the cracks 2, 2' and minute gaps (not shown) at the connection part due to water pressure and earth pressure on the back side of the construction material footwear.

Finally, it oozes out onto the inner wall surface of the construction material frame 1.

When the water-based adhesive liquid appears on the inner wall surface of the construction material, the press-fitting is stopped, and a mixture 6 of the water-based adhesive liquid and early-strength cement, the basic component of which is high molecular weight atactic polypropylene, is press-fitted into the through-hole 4. Let it harden inside and close the through hole.

This mixture 6 of water-based adhesive liquid and early-strengthening cement is press-fitted in as large a quantity as possible so that the mixture 6 forms a layer between the water-based adhesive film 5 and ±3 on the back side of the construction material frame 1. It is desirable to do so.

After the mixture has been press-fitted, a plug 11 made of lead or other suitable material is inserted to close the entrance end of the through hole 4.

One of the key points of the method of the present invention is to pressurize the water-based adhesive liquid through the through-holes of the building material frame, and to diffuse the water-based adhesive liquid onto the back side of the building frame, and to apply the diffused water-based adhesive liquid to cracks in the building material frame. Alternatively, it can be inserted into the minute gap of the connection part from the back side of the side body.

The water-based adhesive liquid that has entered the cracks in the construction material frame or the micro gaps of the connection parts from the back side of the side body and the water-based adhesive liquid that is present on the back side of the construction material gradually hardens over time.
As a result, the former closes cracks and micro-gaps, and the latter forms a protective layer 5 on the back side of the construction material body.

Although the reason why the aqueous adhesive liquid hardens in this way is not clear, it is thought to be as follows.

In other words, if the dispersant contained in the aqueous adhesive solution is affected by the calcium salts and aluminum salts present in the concrete or in small amounts of cement that are mixed into the aqueous adhesive solution during construction. This is because the dispersion function is lost and fine particles of high molecular weight atactic polypropylene and asphalt, which are the main components in the aqueous adhesive liquid, coagulate.

In this way, water leakage can be almost completely prevented by the adhesive liquid infiltrating the water leakage passage in the construction material frame and blocking the passage, and by forming the protective layer 5 on the back side of the construction material frame by the adhesive liquid. The effect lasts semi-permanently.

Another important point in the method of the present invention is the composition of the aqueous adhesive liquid used.

This aqueous adhesive liquid is made of high molecular weight atactic polypropylene, more specifically, an average molecular weight of about 3,000 to about 50,
000 and is a substantially atactic aqueous dispersion of polypropylene.

This aqueous dispersion preferably contains asphalt in addition to the high molecular weight atactic polypropylene, and in this case, the amount of asphalt blended is preferably in the range of 35/65 to 75/25 in terms of asphalt/atactic polypropylene weight ratio.

The term asphalt used here refers to a bitumen whose main component is a hydrocarbon oil component called medium or maltene, a protective substance called asphalt resin, and colloidal particulate or ultrafine particulate carbon, and even if it is natural asphalt. It may also be petroleum asphalt.

Generally, the softening point will be in the range of about 60°C to about 160°C.

This aqueous dispersion may be prepared as follows.

First, a small amount of a dispersant, water and, if desired, a small amount of petroleum resin are added to high molecular weight atactic polypropylene, and these are kneaded under heating, preferably at 70°C to 95°C while applying sufficient shearing force. .

The paste or slurry-like homogeneous kneaded material thus obtained is diluted and mixed with a large amount of water.

In the case of an asphalt-containing aqueous dispersion, the slurry or paste-like kneaded material of high molecular weight atactic polypropylene obtained in the above-mentioned preparation process is mixed with heated molten asphalt and then mixed with a large amount of water, or the slurry or paste is mixed with a large amount of water. After mixing a large amount of water with the mixed substance, this is mixed with heated molten asphalt.

Furthermore, water and asphalt may be added and mixed to the above-mentioned crosstalk substance at the same time.

Dispersants used in the preparation of the above-mentioned aqueous dispersion include anionic activators such as sodium oleate and sodium stearate, nonionic activators such as polyoxyethylene alkylphenol ether, and polyvinyl alcohol, carboxymethyl cellulose and its sodium salt, Examples include water-soluble or water-swellable thermoplastic polymers such as polyacrylic acid and polyacrylic acid amide.

Among these dispersants, saponification degree of 70 to 98%, especially 8
0-97% polyvinyl alcohol is preferred.

The dispersant is used in an amount of 0.03 to 0.5 parts by weight, preferably 0.05 parts by weight, based on 1 part by weight of atactic polypropylene, considering the water resistance of the resulting adhesive and the ability to form a stable dispersion.
~0.3 part by weight is used.

The concentration of the atactic polyrubber pyrene (and the desired asphalt) in the aqueous adhesive dispersion is arbitrary, but it is usually 20 to 70% by weight (total solids concentration) depending on the size of the crack at the leak location. It may be selected appropriately within the range.

Furthermore, in order to hasten the hardening of the aqueous dispersion liquid to be press-fitted or to enhance the effect of blocking water leakage in large cracks, a small amount of cement may be mixed into the aqueous adhesive liquid.

The amount of contamination depends on the solid content concentration of the aqueous dispersion, the size of the cracks,
Select as appropriate depending on the amount of water leakage.

Usually, the amount of cement blended is 40% by weight or less based on the solid content in the unblended aqueous dispersion.

Immediately after stopping the press-fitting of the aqueous adhesive dispersion, a mixture 6 of the aqueous adhesive dispersion and early-strengthening cement is press-fitted to close the through hole, preferably on the back side of the construction material receptacle 1. 60 layers of the formulation are formed between the aqueous adhesive films 5 and ±3.

The amount of early-strengthening cement to be mixed may be appropriately selected in consideration of the fluidity of the mixture.

Then, a plug 11 made of lead, plastic or other suitable material is inserted into the entrance of the through hole 40.

Water leakage can be prevented by the above construction method, but after applying the above construction method, it is desirable to perform the following surface treatment on the inner wall surface of the construction material receptacle.

First, the area around the water leakage point on the wall surface of the construction material frame is scrubbed with a wire brush or the like to remove limescale and other stains (this cleaning may be performed before press-fitting the water-based adhesive).

) Next, an aqueous dispersion containing the above-mentioned high molecular weight atactic polypropylene as a basic component, preferably a diluted solution (solid content concentration 1 to 5% by weight) of an aqueous dispersion containing the polypropylene and asphalt, is used as a brimer to coat the inner wall surface. Paint on.

On top of that, the undiluted aqueous dispersion described above is applied.

The best way to apply this is to first spray an aqueous dispersion of about 300 to 1,001 (solid content)/d on the wall surface, then allow the sprayed film to air dry to some extent before applying a further small amount of the aqueous dispersion. desirable.

In addition to the above-mentioned high molecular weight atactic polypropylene and asphalt, the aqueous dispersion applied here includes
0.1 to 1 part by weight of the atactic polypropylene
Those containing 0.7 parts by weight of synthetic rubber (for example, styrene/butadiene copolymer rubber, imprene rubber, butadiene rubber, neoprene rubber, butyl rubber, ethylene/propylene copolymer rubber, ethylene/propylene/genter polymer rubber, etc.) preferable.

After applying the aqueous dispersion, it is air-dried until a film is formed, and then cement mortar is applied to a thickness of about 5111 mm over the film to complete the surface finishing.

The above-mentioned surface treatment makes the inner wall surface of the construction material frame beautiful, and increases the water leakage prevention effect and its sustainability.

Example This construction method was applied to a railway tunnel that was leaking water from four cracks within a concrete frame area of about 10 m'.

One through hole was drilled in a relatively lower part of the approximately 10 m' area using a drill with a diameter of 16 U (concrete body thickness: 400 m11).

When an aqueous adhesive dispersion having the following composition was injected into this through-hole using an injection machine to a pressure of about 10:9, the adhesive dispersion oozed out from the concrete cracks on the water leakage surface, so the injection was stopped.

The aqueous dispersion used contained 25% by weight of atactic polypropylene with an average molecular weight of about 20,000, 30% by weight of asphalt, 3% by weight of petroleum resin, degree of saponification of 96%, and 2% by weight of polyvinyl alcohol, and about 10% by weight of polyvinyl alcohol. % of Portland cement.

Next, 1,000 f of the above-mentioned aqueous dispersion without Portland cement and 1,000 f of the above-mentioned aqueous dispersion (early strength cement) were poured into the through hole.
A mixture of 11 parts and 11 parts of water was injected under pressure.

After the press-fit was completed, it was pushed into the entrance end of the through hole.

Next, the stains on the concrete on the leaking surface were removed, and a primer prepared by diluting the above-mentioned aqueous dispersion without Portland cement with water 30 times was applied at a rate of about 5 Of/m''.

Next, in addition to the above-mentioned atactic polypropylene and asphalt, an aqueous dispersion containing 0.4 parts by weight of SBR latex (in terms of solid content) per 1 part by weight of atactic polypropylene (solid content concentration approximately 50% by weight) was prepared. ) for i,
It was sprayed at a rate of oooy/d.

When the sprayed film turned black after being air-dried for about 265 hours, the above-mentioned SBR latex-free aqueous dispersion was applied thereon at a rate of about 1 ooyim.

After this coating film was air-dried and turned black, cement mortar was applied thereon to a thickness of approximately 5 degrees.

The above construction completely prevented water leakage, and approximately 1 hour after construction.
After two months, there were no signs of water leakage.

[Brief explanation of drawings]

The drawing is a sectional view of a construction material frame after the water leakage blocking method of the present invention has been applied to the construction material frame. The reference numbers in the figure are as follows. 1: Construction material frame, 2, 2': crack, 3: soil, 4: through hole, 5: membrane formed from aqueous adhesive dispersion, 6: mixture of aqueous adhesive dispersion and early strength cement 7: Primer film; 8, 9: Film formed from aqueous adhesive dispersion; 10: Cement mortar layer; 11: Plug.

Claims (1)

[Claims] 1. Drilling a through hole in a part of the water leakage point in the crack or connection of the construction material frame or in a place near the water leakage point,
Through the through-hole, an aqueous liquid containing high molecular weight atactic polypropylene as a basic component or an aqueous liquid mixed with cement begins to be injected, and the injected aqueous liquid diffuses onto the back side of the construction material frame and this diffusion occurs. The above-mentioned press-fitting is continued until the aqueous liquid leaks into the inner wall surface of the structure through cracks in the structure or minute gaps in the connection parts due to earth pressure and water pressure on the back side of the construction material frame, and then this press-fitting is stopped and the liquid is poured into the through-hole. A method for blocking water leakage from construction material frames such as tunnels and underground passages, which comprises press-fitting a mixture of an aqueous liquid containing atactic polypropylene as a basic component and early-strengthening cement and curing the through-holes to close the through-holes.