JPH08209608A - Resin concrete placing method - Google Patents

Abstract

PURPOSE: To improve construction property without affecting the strength of a structure by providing a mold frame which is formed by the same material as resin concrete at outer periphery of a place where concrete is placed and flowing resin concrete which is not solidified yet thereinto. CONSTITUTION: Resin concrete 25 which is made mostly of methyl methacrylate polymer such as orthophthalic acid unsaturated polyester resin, isophthalic acid unsaturated polyester resin and the like is prepared. Moreover, a mold frame 20 whose cross sectional shape is trapezoid is formed by using the same material as the resin concrete 25. The mold frame 20 is provided at outer periphery of a place where the concrete is placed on a top face of a cement concrete floor plate 10 through a resin mortar 21. Furthermore, the resin concrete 25 which is not cured yet is placed in a space partitioned by the mold frame 20, and excess resin concrete 25 is removed by a beam type vibrator 30 to integrate it with a contact surface with the mold frame 20 so that an elution section 22 is formed and a resin concrete layer 26 integrated with the concrete floor plate 10 is formed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for placing resin concrete, more specifically, a method for placing resin concrete used for increasing the thickness and reinforcement of concrete slabs for bridges, roads, etc., and for repairing various concrete structures. Regarding

[0002]

2. Description of the Related Art With the recent development of organic chemistry, resin concrete that does not use cement as a binder at all and uses only resin has come to be used as a substitute for concrete using ordinary cement. is there. Compared with ordinary cement concrete, this resin concrete has greater flexural tensile strength and elongation ability, better waterproofness, greater resistance to freezing and thawing, less hardening shrinkage, greater impact resistance, greater abrasion resistance, It hardens in a short time and reaches practical strength.

When such resin concrete is used for thickening and reinforcing concrete floor slabs on bridges, roads, etc., a long formwork surrounding the construction area is installed on the upper surface of the existing floor slab to be thickened. Unhardened resin concrete is poured into the frame to integrate the existing floor slab and the resin concrete layer. As a result, the thickness of the resin concrete is added to the existing floor slab made of cement concrete, and the load strength of the concrete floor slab can be easily improved without performing the entire replacement.

Further, also in repairing a cement concrete structure, uncured resin concrete is poured into the existing concrete by pouring the resin concrete into the installed formwork after sufficiently removing the damaged portions such as cracks. Can be deeply penetrated into and integrated with existing structures.

Here, as a formwork for preventing the uncured resin concrete from flowing out, a wooden formwork material which has been conventionally used as a formwork of cement concrete is most commonly used because of its ease of processing. There is. Then, in order to facilitate the demolding after the resin concrete is hardened, a mold release agent is applied or a mold releasing tape is attached to the surface where the resin concrete and the mold are in contact with each other.

[0006]

However, since resin concrete using a resin as a binder has much higher permeability than ordinary cement concrete, the wooden form frame strongly adheres to the resin concrete as it hardens. This makes it difficult to demold the resin concrete after it has hardened, and is an obstacle to improving the construction efficiency. As a countermeasure, it is possible to bury the formwork without removing it from the mold, but when the place of the formwork is at the joint of resin concrete, the material of the formwork differs greatly from the physical properties of resin concrete. In particular, since the wooden formwork is inferior in strength to the resin concrete, it cannot be left as it is because it has a step difference or rots over time to form unevenness.

[0007] In some cases, a steel frame such as a square pipe is used, but in this case as well, since resin concrete strongly adheres to the steel material, it takes time to release the mold. In some cases, the end face of the resin concrete may peel off when the mold is removed. The problem is similar to the original resin concrete containing fine aggregate and coarse aggregate in addition to the binder, mortar containing no coarse aggregate, and paste containing neither fine aggregate nor coarse aggregate. Is a problem that arises. In addition, in this specification, resin concrete shall also include these mortars and pastes.

[0008]

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to solve the above problems in placing resin concrete, and to provide a method for placing resin concrete that does not affect the strength of the structure and is excellent in workability. To do.

[0009]

In order to solve the above problems, the present inventor has conducted earnest research and, as a result, by utilizing the high adhesive strength of resin concrete, it is possible to perform placing without the need for demolding. Therefore, the present invention has been completed. That is, according to the present invention, there is provided a method for placing resin concrete in which uncured resin concrete is poured onto an upper surface of a construction base to be cured, and a formwork preformed with the same material as the resin concrete is placed on the periphery of the place to be placed. It is another object of the present invention to provide a method for placing resin concrete, characterized by pouring the uncured resin concrete into the mold after arranging the mold and integrating the uncured resin concrete with the mold.

Here, the same material means the same kind of polymer of resin concrete, and it is not always necessary to make the mixed materials physically completely the same, but by making them completely the same, The physical properties of the resin and the resin concrete part can be made more uniform. This construction method can be particularly suitably applied to thickening reinforcement of cement concrete floor slabs such as bridges and roads that need to be laid in a large area and repairing cracks, and simply as a formwork for the end of the reinforcement part. Not only can it be used as a formwork for piecing. Also in this case, by forming the resin concrete layers on both sides of the mold, it is possible to form a seamless structure in which the resin concrete layers on both sides and the mold are physically uniform. Incidentally, it is desirable to apply a primer, which is usually used at the time of placing resin concrete, to this form.

As the resin concrete to be used, orthophthalic acid type unsaturated polyester resin, isophthalic acid type unsaturated polyester resin, epoxy resin, furan (furfural acetone etc.) resin, vinyl ester resin, polyurethane resin, phenol resin, Examples include tar epoxy resin, tar urethane, methyl methacrylate (hereinafter referred to as MMA), glycerin methyl methacrylate / styrene, and mixtures thereof, but especially when the construction time is limited during repair work or at low temperatures (in winter). In the case of the construction, the resin concrete mainly composed of MMA type polymer, which is excellent in rapid hardening property and low temperature hardening property, is desirable.

As for the cross-sectional shape of the formwork, a rectangular shape can be used as in the case of ordinary concrete, but in particular, it can be stably installed on the surface of the construction substrate, and the post-cast resin concrete can be used. A trapezoidal shape is preferable in order to increase the adhesion surface with and to improve the compaction efficiency. Furthermore, the height of the formwork can be made to match the casting thickness of the resin concrete in order to facilitate management of the pouring amount of the resin concrete to be cast.

[0013]

[Function] When the uncured resin concrete is placed in contact with the already cured resin concrete, the contact surface of the already cured resin concrete melts out and is seamlessly integrated with the resin concrete placed later. By using a preformed mold of the same material as the resin concrete as the mold, the cured resin concrete layer and the mold having the same physical properties are integrated, and the mold becomes a part of the resin concrete structure. .

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below based on the embodiments shown in the drawings. FIG. 1 is an explanatory view showing a procedure for placing resin concrete. In FIG. 1 (a), 10 is a cement concrete floor slab that is a construction substrate, and 20 are arranged on the upper surface of this cement concrete floor slab with a space. In the formwork, resin mortar 21 is applied to the joint surface between the cement concrete floor slab 10 and the formwork 20 for fixing. The resin mortar 21 also serves as an adjustment when the surface of the cement concrete slab 10 is uneven. Reference numeral 30 is a beam-type vibrator for forming and compacting a flat surface placed on the upper surfaces of the molds 20, 20, and 2 to 3 units are installed for each 3.5m in length of the mold 20. Further, this beam type vibrator 30 is of a self-propelled type such that road floor slabs can be continuously constructed, and tapping and pressing are arranged alternately. This uniformly compacts and prevents unevenness on the finished surface.

The mold 20 is formed in advance with the same material and with the same composition as resin concrete described later, and its shape is not particularly limited, but in this example, it is formed in a trapezoidal shape. This formwork 20 is shown in FIG.
It can be easily obtained by casting resin concrete on a frame 40 extending upward as shown in FIG. 4 and hardening it. At this time, by setting the mold frame 20 to have a trapezoidal cross section, the hardened mold is obtained. Frame 20 to frame 4
It can be taken out easily from 0 without damage.
Further, by forming the form of the form into a trapezoid, it can be stably installed on the cement concrete floor slab 10. In addition, it goes without saying that the cross-sectional shape of the mold can be formed into any shape such as a rectangle or a square as in the conventional case. Further, it is desirable to apply a primer, which is usually used when pouring resin concrete, to this formwork.

Next, as shown in FIG. 1B, the form 2
Unhardened resin concrete 25 in the space divided by 0
Pour. At this time, the uncured resin concrete is
A slightly larger amount than the thickness of the mold is poured, excess resin concrete is removed by the operation of the beam vibrator 30, and the hardened surface can be compacted without unevenness and has a smooth surface easily. In addition, the required thickness can be secured. Therefore, the thickness of the resin concrete to be laid can be arbitrarily changed by changing the height of the mold.

Here, due to the weldability which is a characteristic of resin concrete, as shown in the partially enlarged view of FIG. 1 (b),
By placing the uncured resin concrete 25 in contact with the mold 20 made of resin that has already hardened, the elution part 22 is formed integrally with the contact surface of the mold 20 that has already hardened. It will be seamlessly integrated with the resin concrete 25 cast later. As a result, as shown in FIG. 1 (c), the resin concrete layer 26 and the formwork 20 are completely integrated, and the resin concrete layer 26 is also integrated with the cement concrete floor slab 10.

As described above, according to the method for placing resin concrete of the present embodiment, since the mold itself is made of the same material as the resin concrete, the conventional mold which is in close contact with the resin concrete layer is removed. It can be installed without any work, and work efficiency can be greatly improved.
Moreover, since the formwork and the resin concrete layer are completely integrated, the strength is also excellent.

<Experimental Example 1> As the MMA resin concrete to be placed, Silica R manufactured by Mitsui Petrochemical Co., Ltd.
17 construction methods were used. The composition is R17 (liquid resin) =
5.5kg, R7 / 17 (premix bone agent) = 45k
g, as coarse aggregate, AG10 (gravel) = 10 kg, AG
20 (gravel) = 35 kg and BPO (benzoyl peroxide 50% pure product) = 360 g were used as a curing agent. The procedure is as follows: Fine aggregate R7 / 17 and coarse aggregate AG1
No. 0 and AG20 were kneaded by a pan-type mixer, then R17 in which BPO was dissolved was added in another container and mixed uniformly. In addition, an MMA-based primer (Mitsuishi Kasei)
Silical R51 manufactured by Co., Ltd.
The MA-based resin paste was used as an adhesive and stuck onto a cement concrete floor slab.

Thereafter, the resin concrete having the above-mentioned composition which was kneaded with a pan-type mixer was placed in a mold, and a beam-type vibrator was continuously applied for rolling and surface finishing. As a result, it was confirmed that the formwork and the resin concrete layer were completely integrated and strongly bonded to the concrete slab. A test piece of the resin concrete layer portion and a portion including the boundary between the formwork and the resin concrete layer were sampled and subjected to a strength test. Both of them had a compressive strength of 600 Kgf / cm ² , which indicates that the formwork and the resin concrete layer were It was confirmed that the boundary disappeared and it was completely integrated.

<Comparative Example 1> Wood was used as the mold, and the same material as in Example 1 was used to carry out the work. A release agent was applied to the wood in advance, and it was fixed to the construction site using concrete nails. During rolling compaction work after placing the resin concrete, liquid resin components were seen to flow out from the gap between the ground irregularities and the formwork wood, and the liquid did not float above the material when compacting. Also, since the formwork and resin concrete layer are strongly bonded, it takes 5 minutes / m to remove the formwork, and 5 or 5 to remove MMA resin that has settled in the gap between the base and the formwork. Spent 10 minutes / m.

[0022]

According to the present invention, the following effects can be obtained. (A) By using a mold preformed with the same material as the resin concrete to be cast, the contact surface of the mold that has already hardened melts out and the resin concrete layer and the mold are integrated. It is not necessary to remove the mold after hardening the resin concrete, and the required strength can be easily secured. (B) By being used as a cement concrete slab for bridges, roads, etc., it can be used not only as a formwork for the end of the reinforcing part, but also as a formwork for a large-area piecing joint, thus improving the construction efficiency. Can be improved. (C) The use of methyl methacrylate-based resin concrete has an effect of drastically shortening the time (rapid curing) particularly when forming the mold. (D) By using a trapezoidal cross-sectional shape of the mold, the mold can be stably installed on the surface of the construction substrate. (E) By matching the height of the formwork with the casting thickness of the resin concrete, the pouring amount of the resin concrete to be cast can be easily controlled.

[Brief description of drawings]

FIG. 1 is an explanatory view showing a procedure for placing resin concrete of the present invention.

FIG. 2 is a perspective view of a frame for manufacturing the mold of the present invention.

[Explanation of symbols]

 10 Cement concrete floor slab (construction base) 20 Form 21 Resin mortar 22 Leaching part 25 Unhardened resin concrete 26 Resin concrete layer 30 Beam type vibrator 40 Frame

Claims (5)

[Claims] 1. A method for placing resin uncured on an upper surface of a construction base, which is cured by pouring uncured resin concrete, wherein a formwork made in advance of the same material as the resin concrete is provided on the outer periphery of the place to be placed. After that, the uncured resin concrete is poured into the mold to integrate the mold with the mold. 2. The method for placing resin concrete according to claim 1, wherein the construction substrate is a concrete floor slab. 3. The method for placing resin concrete according to claim 1, wherein the resin concrete is mainly composed of a methyl methacrylate polymer. 4. The method for placing resin concrete according to claim 1, wherein the form has a trapezoidal vertical cross section. 5. The method for placing resin concrete according to any one of claims 1 to 4, wherein the height of the mold is matched with the thickness for placing the resin concrete.