JPH0480420A - Civil engineering method using foamable resin - Google Patents

Abstract

PURPOSE:To form a foam having strength necessary for a shape of the field ground by spouting foaming particles of foamable resin, which is aged by foaming preliminarily, together with adhesives to from a foaming particle lump in the field ground, and applying external pressure thereto. CONSTITUTION:Foaming particles 4 of foamable resin aged by foaming preliminarily are spouted together with adhesives 6 to form a foaming particle lump 10 in a field ground such as a hollow 9. External pressure is applied to the foaming particle lump 10, and a foam 11 having strength necessary for a shape of the field ground is formed. According to the constitution field work for preliminary foaming and aging, etc., can be obviated.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to civil engineering work using a foamable resin that forms a foam material of a desired shape on the ground at the site to simplify the work when performing civil engineering work such as filling in potholes, creating mounds, and widening roads. .

[Conventional technology]

Attempts have been made to use foamed resins to fill depressions or form part of artificial ground. For example, foamed resin is molded into foam blocks of a predetermined shape in a factory, and the foam blocks are piled up on the ground at the site where the embankment is to be made, and the surface layer is finished with concrete floor plates, wall protection materials, etc. Additionally, reinforcing materials such as reinforcing bars are placed inside to improve structural strength. When forming the ground by stacking foam blocks, misalignment is likely to occur between the foam blocks. Therefore, Utility Model Application No. 63-81941, Utility Model Application No. 63-819
In order to eliminate this misalignment, Japanese Patent Publication No. 42 and the like introduces the method of forming irregularities on the surface of the foam block and interlocking the irregularities. Furthermore, Japanese Patent Application Laid-Open No. 47-19617 discloses that after spraying an unfoamed resin such as urethane, vinyl chloride, or styrene onto a depression or roadbed, a foaming reaction is caused to fill the depression. There is. [Problems to be Solved by the Invention] By the way, when using foam blocks pre-produced in a factory as described above, the ground at the site must be leveled in advance so that the foam blocks can be laid without gaps and stacked. It is necessary to create it. Also, if the foam block used is large (2XIX
(about 0.5 m) requires manpower to transport and stack on-site, making on-site work more troublesome than expected. On the other hand, as described in Japanese Patent Application Laid-Open No. 47-19617,
Although this problem does not arise in the method of foaming the foamable resin on-site, the publication does not specifically teach how to foam the foamable resin. Here, in order to form a foam of a desired shape using a foamable resin, steps such as pre-foaming, aging, and pressure molding are generally required. However, in order to form a large foam suitable for the ground at a civil engineering work site, uniform pre-foaming and aging must be carried out, and it is expected that it will be a national problem to carry out site work reliably and easily. SUMMARY OF THE INVENTION Therefore, an object of the present invention is to make it possible to form a foam in a desired shape according to the shape of the ground at the site, while ensuring reliable and simple on-site work. [Means for Solving the Problems] For this purpose, the present invention jets out foamed beads of a foamable resin that have been pre-foamed and aged together with an adhesive to form a foamed mass on the ground at the site, and It is characterized by applying external pressure to the mass to form a foam in the desired shape on the ground at the site.

[Function 1] In such a method, the foamed particles of the foamable resin are bonded to each other with an adhesive to form a foamed granule mass, and by applying external pressure to this, the ground at the site has the required strength according to its shape. A foam is formed. [Embodiment] Hereinafter, an embodiment of the present invention applied to the filling work of a depression will be specifically described with reference to the attached drawings. First, the schematic configuration of one embodiment will be explained with reference to FIG.
As the material for filling the hollow, foamed granules are used which are pre-foamed with steam from a foamable resin raw material and then matured by air drying. Then, the foamed particles are ejected together with the adhesive through a hose while being carried by the blower airflow, thereby forming a foamed particle mass in the depression. Next, external pressure is applied to the foamed granules to form a foamed body in the desired shape within the depression. Various types of foamable resin raw materials are commercially available, such as polystyrene resins, phenol resins, urea resins, and urethane resins. The typical polystyrene resin contains a blowing agent such as butane or pentane and has a particle size of 0.7 to 0.
．． It has a diameter of 9 mm and is used as a raw material. Then, water vapor at around 100° C. is supplied to this polystyrene resin raw material to pre-foam it. Thereafter, the mixture is aged by blow drying for about 12 hours to obtain expanded granules. The expanded beads of the expandable resin thus obtained have an expansion ratio of about 30 to 50 times. The adhesive to be placed on the blower air stream together with the foam particles is as follows:
For example, a liquid organic compound (chain hydrocarbon, cyclic hydrocarbon) is used, and this adhesive is used to penetrate and adhere the semipermeable membrane between the foam particles. FIG. 2 shows the configuration of the device used in this example.
A hose 3 is installed at the outlet of the blower 2 that sucks air through the
is connected to the hose 3, and a hopper 5 into which the foamed beads 4 are introduced is connected in the middle of the hose 3. This hopper 5 includes a screw auger 5 which is rotationally driven by a motor 5a.
b allows the inserted foam particles 4 to be fed into the hose 3. Further, a tank 7 storing the adhesive 6 is connected to the hose 3 downstream of the hopper 5 via a pump pressure feed pipe 8. As the blower 2 operates, the foamed particles 4 supplied from the hopper 5 into the hose 3 are carried by the blower airflow, and the adhesive 6 in the tank 7 is transferred into the hose 3 through the pump pressure pipe 8. The foamed particles 4 are sprayed in the form of a spray and adhere to the surface of the foamed beads 4. Note that the reason for using the heater 1 is to improve the adhesion of the adhesive 6. Further, the pump pressure feed pipe 8 can be made into a suction pipe by providing a venturi part in the hose 3. In this case, the adhesive 6 in the tank 7 is sprayed into the hose 3 through the suction pipe. It is sucked in. Then, the blower 2 is operated to blow out the foam particles 4 together with the adhesive 6 into the depression 9 where the hole is to be filled. In this case, the amount of foam particles 4 ejected is 3 m above the inner volume of the depression 9.
3 is 30 to 90 kg. Then, as shown in FIG. 3(a), the surface of the foamed granules 1o filled in the depression 9 is compacted using a roller or the like. By doing this, the individual foam particles 4 constituting the foam particle mass 10 are adhered to each other by the adhesive 6, and a foam 11 corresponding to the shape of the depression 9 is formed in the depression 9 as shown in FIG. 3(b). It is formed. The foam 11 thus obtained has a density of 10 to 30 kg.
/m' and the surface was dense. Here, the graph in Figure 4 shows the experimental results for determining the relationship between foam density and compressive stress. This is the measurement of the compressive stress value when applying . As is clear from this graph, the strength of the foam increases as the density increases, and at a density of 30 kg/m 3 , a compressive strength of about 1.3 kg/cm 2 is obtained. Therefore, considering that the stress generated under the pavement surface under normal traffic loads is 0.5 kg/arn2 or less,
The foam 11 formed in the depression 9 has a compressive strength of 1.3.
It can be seen that the pressure strength is approximately kg/cm2, which is sufficient for pressing force. In addition, although the above-mentioned embodiment explained the work of filling in a depression, the present invention is also applicable to work of filling in a continuous long trench,
It can also track the creation of rocky mountains and road widening construction using formwork. [Effects of the Invention] As explained above, according to the present invention, foamed beads of a foamable resin are adhered to each other with an adhesive to form a foamed grain agglomerate, and by applying external pressure to this, a foamed body having the required strength is formed. be done. Therefore, it is possible to form a foam having a required strength depending on the shape of the ground at the site. Furthermore, since the foamable resin handled at the site is foamed granules that have been pre-foamed and matured, the site work of pre-foaming and ripening is not required, making the site work reliable and simple.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a schematic configuration of an embodiment of the present invention, FIG. 2 is a side view showing the configuration of a device used in one embodiment, and FIG. 3(a) is a block diagram showing a schematic configuration of an embodiment of the present invention. FIG. 3(b) is a cross-sectional view of a foamed mass formed in accordance with one embodiment. FIG. 4 is a graph showing the relationship between the density of the foam and the compressive stress. DESCRIPTION OF SYMBOLS 1... Heater, 2... Blower, 3... Hose, 4... Foamed grain, 5... Hopper, 5a... Motor, 5b... Screw auger, 6...
...fusing agent, 7...tank, 8...pump pressure pipe, 9...recess, 10...foamed granule agglomerate, 1...foam.

Claims (1)

[Claims] Foamed particles of foamable resin that have been pre-foamed and matured are ejected together with adhesive to form a foamed mass on the ground at the site, and external pressure is applied to this foamed mass to form a foam of the desired shape on the ground at the site. A civil engineering method using foamable resin.