JPH045322A - Charging civil engineering work method using foaming resin - Google Patents

Abstract

PURPOSE:To obtain a foaming unit of required strength by charging a foaming work site, whose foaming volume is regulated by a form or the like, with foaming resin material beads suitable for this work site, injecting heated gas to these material beads, and stirring and foaming them. CONSTITUTION:Material beads 2 are input by a required amount into a charging work site 1 whose required volume is regulated, and it is covered with a mold plate 3 having steam vents 3a. Four injection nozzles 4 are arranged with an equal space in the mold plate 3 and provided toward a bottom part 1a of the charging work site 1. The injection nozzle 4 is connected to a pressure regulating valve 7, pump 6 and a boiler 5. Next, the material beads 2 are stirred in the charging work site 1, heated and foamed uniformly by injecting pressurized steam from the injection nozzle 4. The inside of the charging work site 1 is charged with a foaming unit in a condition that compression force is received by restricting the foaming volume. In this way, the charged foaming unit can be formed in a ground constitutional member having required strength.

Description

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

The present invention facilitates civil engineering works such as filling in depressions such as holes and ditches, embanking roads, and forming artificial ground by foaming foamed resin into the required shape on site and filling the work. Regarding civil engineering work.

[Conventional technology]

Attempts have been made to take advantage of the lightweight nature of foamable resins to fill depressions or use them as part of artificial ground. For example, foamable resin is molded into foam blocks of a predetermined shape in a factory, the foam blocks are piled up on the original ground that is to be embanked, 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 a foundation by stacking foam blocks, misalignment is likely to occur between the foam blocks. Therefore,
Utility Model Application No. 63-81941, Utility Model Application No. 63-8194
In order to eliminate this misalignment, Patent Publications No. 2 and the like introduce 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.

[Problem to be solved by the invention]

However, the method of transporting foam blocks that have been foamed in a factory to the site and stacking them into a predetermined shape requires time and effort to transport and handle. For example, a large block of about 5 m, such as 2XI In addition, the transportation
This is essentially like transporting air, and there is a lot of waste. Moreover, the larger the blocks, the more likely it is that gaps will form between the original ground on which work such as embankment is to be performed and the blocks that have been laid. On the other hand, Japanese Patent Application Laid-Open No. 47-19 discloses that foamable resin is foamed on-site.
The method described in Japanese Patent No. 617 solves this problem. However, this publication does not specifically teach how to foam the foamable resin. By the way, if the resin is simply foamed, the surface of the resin body after foaming often does not have the required contour due to non-uniform foaming or the like. In addition, when foaming occurs at the free interface,
The surface strength of the foam is insufficient and dents are likely to occur when treading pressure is applied. Therefore, the present invention aims to uniformly foam the foamable resin at the filling site to obtain a foam with the required strength. purpose.

[Means to solve the problem] For this purpose, the present invention introduces a required amount of foamable resin raw material beads into a filling site where the foaming volume is regulated by a mold, etc., and agitates the raw material beads by injecting heated gas such as steam into the raw material beads. The filling site is filled with foam having the required strength. [For production]

In such means, raw material beads are uniformly heated and foamed while being stirred within the filling site by injection of heated gas such as water vapor. Then, a required amount of raw material beads is foamed in a filling site whose foaming volume is regulated and subjected to compressive force, thereby filling the filling site with a foam having the required strength. The injected heated gas is discharged outside the filling site or recovered by appropriate means. Various foamable resins used in the present invention are commercially available, such as styrene resins, phenol resins, urea resins, and urethane resins. And the foaming temperature of the foamed resin is
The temperature may be set as appropriate depending on the type of resin, but it is usually 70 to 20
A sufficient foaming reaction can proceed at about 0°C. Furthermore, the strength of the foam can be adjusted depending on the degree of foaming. The field surface filled with foam is preferably compacted using topsoil. In this case, members such as formwork that regulate the foam volume at the filling site may be buried as ground components at the filling site, or if the foam is formed in multiple stages sequentially, they can be moved and reused in sequence. It is also possible to use

【Example】

EMBODIMENT OF THE INVENTION Hereinafter, one embodiment of the present invention applied to filling a depression will be specifically described with reference to the accompanying drawings. As shown in FIG. 1(a), a required amount of foamable resin raw material beads 2 is put into a filling site 1 to be filled, and the filling site 1 is covered with a template 3. The template 3 used is one having a large number of small holes 3a for venting steam, as shown in FIG. 2, and is fixed to the ground at the site by appropriate means such as piling. Then, an appropriate number of injection nozzles 4 are attached by penetrating this template 3. In this case, the injection nozzles 4 are installed so as to stir the input raw material beads 2. In this embodiment, four injection nozzles 4 are arranged at equal intervals around the filling site 1. It is installed with the tip facing the bottom 1a of the filling site 1. Next, the steam S generated in the boiler 5 is transferred to a pressurizing pump 6.
This is pressurized with a pressure regulating valve 7 and is injected from four injection nozzles 4 through a hose 8 having a pressure regulating valve 7. Here, the input amount of the raw material beads 2 was 90 kg, assuming that the internal volume of the filling site 1 was 3 m3. Moreover, as the raw material beads 2, styrene resin beads with an average particle diameter of 0.9 mm were used. The foaming reaction of these resin beads changes as shown in Figure 3 depending on the relationship between temperature and time.
When foaming is stopped, it expands into a foam with a foaming ratio of about 30 to 45 times, and the density of the foam is about 0.015 g/cm
3. The temperature of the water vapor S injected as a heated gas is 10
The temperature was 0° C., and this was injected for 15 minutes at a flow rate of 0.4 m 3 per minute under a pressure of 7 kg/cm 2 . Under such conditions, when pressurized steam S is injected from the injection nozzle 4, the raw material beads 2 are stirred within the filling site 1, as shown in FIG. As air was forced out through the small holes 3a of the template 3 and replaced with water vapor S, it was uniformly heated and foamed. At this time, since the foaming volume was regulated by the template 3, the raw material beads 2 were subjected to a compressive load in the latter stage of foaming, becoming a highly dense foam and filling the filling site 1 without any gaps. The foam thus obtained had an expansion ratio of about 35 times, a density of about 30 kg/m3, and a dense surface. Here, FIG. 4 is a graph showing the experimental results of the relationship between foam density and compressive stress, at 20°C and 55% RH.
The compressive stress value was measured when a compressive strain of 4% was applied to a test piece of 50 x 50 x 50 mm in an atmosphere of . As is clear from FIG. 4, the strength of the foam increases as the density increases, and at a density of 30 kg/m3, a compressive strength of about 1.3 kg/cm2 is obtained. This compressive strength indicates that the ground has sufficient tread pressure strength, considering that the stress generated under the pavement surface under normal traffic loads is 0.5 kg/cm2 or less. It is. In addition, even if the foaming density is 20kg/m3, it is 0.5kg/cm.
Since a compressive strength of 2 or more can be obtained, it is advantageous to lower the foaming density as much as possible when considering raw material consumption and weight reduction. In addition, although the above-mentioned example explained the filling work of a depression, the filling civil engineering method of the present invention can also be applied to the work of filling a continuous long trench by providing a partition wall to partition the inside of the trench and performing the work for each section. can.

【Effect of the invention】

As explained above, according to the present invention, the raw material beads are uniformly heated and foamed while being stirred in the filling site by injection of heated gas such as water vapor, and at that time, the foamed material is subjected to compressive force by regulating the foaming volume. The fuel is filled at the filling site in the same state as before. Therefore, the filled foam develops the necessary strength to withstand tread pressure, and functions satisfactorily as a soil construction material.

[Brief explanation of drawings]

Figures 1 (a) and (b) are diagrams for explaining one embodiment of the present invention, Figure 2 is a perspective view of the same, and Figure 3 shows the foaming reaction of styrene resin beads used in one embodiment. Figure 4 is a graph showing the relationship between temperature and time. Figure 4 is a graph showing the relationship between foam density and compressive stress. 1...Filling site, 2...Raw material beads, 3.
... template, 3a... small hole, 4... injection nozzle, 5... boiler, 6... pressure pump, 7... pressure regulating valve, 8... hose.

Claims (1)

[Claims] The required amount of raw material beads for foamable resin is put into the filling site where the foaming volume is regulated using molds, etc., and heated gas such as water vapor is injected into the raw material beads to stir the raw material beads and foam on site. A filling civil engineering method using foamable resin, which is characterized by filling with foam of the required strength.