JPS59179908A - Reinforcement of floor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a floor reinforcement method suitable for application to elevated roads and the like.

Conventionally, when an 8-overpass road becomes obsolete or the traffic volume increases from the original design level, a steel reinforcing girder 2 is fixed to the existing cross girder 1, and the gap 4 between the reinforcing girder 2 and the floor 3 is filled with cement concrete. It is being done to increase the load capacity by filling and solidifying K-oxy resin.

However, cement concrete compositions do not provide sufficient adhesion to reinforcing girders and durability, and reinforcing methods using epoxy resins have the following drawbacks.

That is, this construction method, for example, in Figures 1 and 2,
A rectangular parallelepiped @5 having approximately the same width as the upper part of the girder is placed with an appropriate gap in the longitudinal direction of the reinforcing girder 2, and by applying two side plates 6, a two-component mixed type liquid epoxy is applied. Epoxy resin 7 is injected and solidified through a seventh generation eve (not shown) to prevent the resin from leaking to other parts, but the back side of the floor often has recesses 8 of various sizes due to aging. Even when the liquid resin is injected, air remains in the recess 8 as shown in FIG. 2, and voids often remain in the end, making it impossible to expect a uniform reinforcing effect at each floor position. In addition, installation of the side plate 6 and removal after the epoxy resin has solidified are troublesome, and it takes a long time for the epoxy resin to harden, especially in a low-temperature atmosphere of about 10° C. or less, resulting in poor workability. Ta.

Furthermore, since epoxy resin, which is an organic compound, is used as a reinforcing material for roads that are subjected to repeated stress over long periods of time, it has a poor track record of durability, so it is recommended to use inorganic reinforcing materials that are more compatible with concrete. I had high hopes.

In view of the above-mentioned drawbacks of the conventional floor reinforcement method, the present invention uses a polymer cement composition that contains an inorganic material and has good adhesion to the floor and the reinforcing girder so as not to create a void between the floor and the reinforcing girder. The purpose of this project is to provide a construction method that can be filled with concrete and has excellent workability and economic efficiency. The present invention relates to a method for reinforcing a floor, which is characterized by filling the gap with a polymer cement composition and curing it.

Kibatsu+! Polymer-cement compositions containing water cement, cement polymers, and aggregates in IVc, when solidified, are called polymer-cement concrete.

As the cement added to the above composition, Portland cement, alumina cement, mixed cement, etc. are frequently used, and these may be used alone or in an appropriate mixture. Cement polymers are also called convex molecule admixtures, and they exist as polymers in cured polymer cement and are mixed for the purpose of improving the quality of adhesion to concrete floors and steel reinforcing girders. Natural rubber, taloloprene rubber, butadiene rubber, styrene-butadiene rubber,
Synthetic rubbers such as acrylonitrile-butadiene rubber, methyl meccrylate-butadiene rubber, polyvinyl acetate,
Examples include ethylene-vinyl acetate copolymer, styrene-acrylic copolymer polyacrylate, polyvinyl chloride, polyvinylidene chloride, polyvinyl propionate, and the like.

Most of these, except for natural rubber, are synthesized by emulsion polymerization, and then stabilizers, antifoaming agents, etc. are added as necessary.
It is usually used in the form of Viumulsion or latex. In addition, water-soluble polymers such as polyvinyl alcohol, polyacrylate, polyethylene oxide, methyl cellulose, and hydroxyethyl cellulose can also be used as workability improving materials as cement polymers.

Preferred examples include polyurethane rubber, acrylonitrile-butadiene rubber, ethylene-vinyl acetate copolymer, and styrene-acrylic copolymer, with styrene-butadiene rubber and ethylene-vinyl acetate copolymer being particularly preferred. However, if the amount of these polymers added is too small, the adhesion of the polymer cement composition will be poor, and if it is too large, there will be problems in terms of strength and economic efficiency. The amount is 3 to 30 parts by weight. In order to obtain polymer cement concrete with excellent adhesion to the floor and reinforcing girder and high rigidity, a composition with a high proportion of polymer within the above range is applied as a primer to the floor and reinforcing girder, and then A lower composition may be filled between the floor and the reinforcing girder.

Most of the aggregates added to the above polymer cement composition are fine aggregates, especially those with a particle size of 2.5 mm. ．． Gui sand whose main component is 5% or less of silicic acid anhydride is preferably used, and from the viewpoints of workability, shrinkage properties during curing of the polymer cement composition, various strengths after curing, and economic efficiency, it is usually 100% by weight of cement. The amount of coarse aggregate used is 400M parts or less, and on the other hand, conventionally known chestnut stones, crushed stones, etc. for cement concrete can be used as the coarse aggregate. Furthermore, in order to increase the various strengths of polymer cement concrete, alkali-resistant glass fibers may be mixed. Such glass fibers usually have a diameter of 2 to 15 .mu.m and a length of 3 to 50%, preferably a diameter of 7 to 13 .mu.m and a length of 3 to 10%.

The present inventors have confirmed that the polymer cement composition has significantly greater waterproofing performance than conventional cement compositions, but it is possible to improve the waterproofing performance by improving the durability of sibolimer cement concrete. Various waterproofing agents may be added to the polymer cement composition. Preferred examples of the waterproofing agent include amorphous aluminum silicate in which the molar ratio of aluminum oxide to silicon dioxide is 1:1 to 1:10, and synthetic amorphous aluminum silicate in which the molar ratio of aluminum oxide to silicon dioxide is approximately 1:9. Particularly preferred is aluminum silicate.

Compared to conventional cement compositions, the polymer cement compositions mentioned above have excellent waterproof properties and excellent adhesion to concrete and iron, and have extremely low fluidity compared to liquid epoxy resins, making it possible to achieve desired results. When filling the gap, methods such as extrusion with a gun, pressure feeding with a pump, or coating with a brush can be used if necessary. Therefore, even if there are four parts on the back side of the floor, the gap can be filled without leaving any gaps. It is.

Hereinafter, the construction method of the present invention will be explained with reference to the drawings showing one embodiment.

First, 100 parts by weight of ordinary Portland cement, 35 parts by weight of a styrene/getadiene copolymer emulsion (solid content 45% by weight), and 200 to 40 parts of silica sand with a particle size of L5 or less.
A polymer cement brimer obtained by adding 0 parts by weight of on-site mixed water and stirring is applied to the upper surface of the reinforcing girder 2 made of H-shaped steel of the elevated road 3. It is convenient to perform this work before going to the construction site. Next, apply the above primer to floor 3.
Apply it to the back side of the reinforcing girder 2 and fix it with the existing cross girder IK bolts, etc. In Fig. 3, 4 is the gap between the back surface of the floor 3 and the upper surface of the reinforcing girder 2, which is usually 2 to 3σ, in some cases about 7LM, and 9.10 is a single layer of primer with a coating amount of about 0.5 Kq/m+. be.

Next, a rectangular parallelepiped made of polymer cement concrete whose height is slightly lower than the above-mentioned gap 4 is divided into two halves 11, 1.
2, 11 is placed on the primer layer 9 so that the right end in FIG. For installation, it is adhered to the floor 3 using a primer 10. Model 11.
12 are provided at intervals of approximately 50 to 60 LM in the longitudinal direction of the reinforcing girder 2, and on the left and right sides of the upper portion of the girder 2, as shown in FIG.

Thereafter, the proportion of the polymer is smaller than that of the polymer cement primer, for example, 27 parts by weight of the copolymer emulsicone per 100 parts by weight of the cement, 200 to 400 parts by weight of the silica sand, and glass fibers having a length of 10 to less. A polymer cement composition is prepared by adding a small amount of Kffl mixed water, and the composition is filled into the gap 4 by extrusion from a gun or pumped, and cured to obtain a polymer cement concrete layer in the shape of a square column. The polymer cement composition flows in about 30 minutes immediately after being filled at room temperature.
The sense of humor has disappeared.

If there is a need for aesthetics or physical properties, the polymer cement composition may be applied on both sides of the body with tapers 13 as shown in FIG. As the molds 11 and 12, it is preferable to use the same composition as the polymer cement composition, which has a lower polymer component than the primer, in advance by placing it in a mold and sufficiently curing it to solidify.

In addition, as a treatment for the recesses 8 occurring on the back surface of the floor 3, if the recesses are minute, it may be sufficient to apply a thick layer of primer, but if the recesses are deep and widespread, the above-mentioned polymer cement composition with a lower polymer component than the primer may be used. It is preferable from the viewpoint of operation and physical properties to partially fill the material. Note that 14 is a hardened polymer cement concrete layer.

The method of the present invention is also preferable in that the Young's modulus of the polymer cement concrete formed is much higher than that of the conventionally used Evokin resin.

That is, according to the findings of the present inventors, when using styrene-butadiene rubber or ethylene-vinyl acetate copolymer as the polymer, the polymer-cement ratio, water-cement ratio, polymer specifications, etc. are within the normal usage range. Comparing polymer cement concrete with conventional epoxy resins used in floor reinforcement construction methods, the Young's modulus of the former is about 3 to 9 times that of the latter (however, the Young's modulus of polymer cement concrete is 1-tJlsA1132 and JISA
It was calculated from the compressive strength according to 1108. ).

On the other hand, in order to ensure safe driving of vehicles, some of the corners of elevated roads are provided with floors that gradually rise from the inside to the outside of the passageway, as shown in Figure 5. Due to the influence of centrifugal force, the amount of floor deflection is generally larger than that of straight sections, but in this case, a polymer with a Young's modulus larger than that of an epoxy resin and therefore with a higher bending stiffness than that of the epoxy resin is used as a gap filler between the floor 3 and the reinforcing girder 2. By using the cement composition, the extent to which the floor 3 bends in the direction of the arrow can be further reduced.

The construction method of the present invention is constructed as described above, and includes 1. Since it is filled with a polymer cement composition and there is no need to inject a highly fluid liquid material, the present invention does not leave any voids caused by the four parts that occur on the back surface of the floor in the above-mentioned gap. A complete polymer cement concrete filled layer can be easily installed not only at room temperature but also in a low temperature atmosphere.

In addition, the polymer cement I composition used in the present invention contains inorganic sludge such as cement and sand, and has good adhesion to concrete and iron, compared to the case where an epoxy resin, which is an organic compound, is used. It is expected that the above-mentioned gap-filling layer will have better durability, and since the Young's modulus of the polymer cement concrete layer is higher than that of epoxy resin, it will be possible to reduce the deflection of the floor, especially at curved sections of elevated roads. preferable.

[Brief explanation of the drawing]

Figures 1 and 2 are related to the conventional construction method, and Figure 1 is a cross-sectional view of the existing cross beam of an elevated road with reinforcing girders attached.
In Fig. 2 Viqi diagram, a partially omitted cross-sectional view along the ■-■ arrow of the state in which epoxy resin is injected into the darkness between the floor and the reinforcing girder, and the third
Figures 5 to 5 relate to one embodiment of the construction method of the present invention. Figure 3 is a sectional view of the main part of the reinforcing girder coated with primer and fixed to the cross beam after primer has been applied to the underside of the floor, and Figure 4 The figure further shows a cross-sectional view of a main part of a shape in which a polymer cement) tA composition is filled into the gap and solidified, and FIG. 2 - Reinforcement girder, 3... Concrete floor, 4 - Gap Patent applicant Mototoshi Fujinuma Representative of Sekisui Chemical Co., Ltd. Figure 1 Figure 2 @ 3 @ Figure 4

Claims (1)

[Claims] L. A method for reinforcing floors, which comprises filling a polymer cement composition into a gap formed between the back surface of concrete powder and the soil surface of a steel reinforcing girder and hardening it. 2. The reinforcing method according to item 1, wherein the polymer in the polymer cement composition is styrene butadiene rubber. 3 The polymer in the polymer cement composition is ethylene-
The reinforcing method according to item 1, which is a vinyl acetate copolymer.