JPH0449313A - Lightweight filling method - Google Patents

Abstract

PURPOSE:To promote integration efficiency between a foamable plastic layer and the ground by forming a polyurethane film layer on the ground surface of the lower part and/or side of the ground, and forming a polyurethane foamable layer on the upper part and/or side of the ground. CONSTITUTION:After the central part of a road is filled with sand 2, a polyurethane film layer 3 is formed in advance on the ground surface of the lower part and/or side of the ground 1 excavated in the shape of the bottom of a ship.. After that, a polyurethane foamable layer 4 is formed on the upper part and/or side of the polyurethane film layer 3. Adhesion between the polyurethane foamable layer and ground 1 is promoted by using the polyurethane film layer 3 and, at the same time, adhesion between the ground 1 is promoted by using the polyurethane film layer 3 and, at the same time, adhesion between the ground and a foamable polyurethane filling layer 4 is strengthened. Adherence and adhesion to the polyurethane film layer 3 is promoted by using the foamable polyurethane filling layer 4.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to an embankment applied to earthen structures such as embankments on soft ground, embankments on reclaimed land, and retaining walls.

[Prior art]

Conventionally, the techniques related to the above-mentioned embankment include (1) simply:
Embankment construction method consisting of earth, sand, gravel, etc.; (2) Embankment construction method in which a structural layer of foamed material, such as foamed polystyrene blocks, is laid inside; (3) Sheet-like material on the surface of soft ground. (4) urethane is injected into the metal formwork on-site and foam molding is performed. A variety of construction methods have been adopted, including methods for embanking the earth using this material.

However, method (1) has the problem of high earth pressure due to the high density of the material, resulting in consolidation settlement and slippage at the bottom of the embankment, while method (2) has the following problems: There is a lack of integrity between the blocks or between the block structure layer and the underlying ground, which may cause the blocks to shift and cause subsidence when large overload loads are applied, and the resistance to horizontal forces is extremely weak. There is a problem. In method (3), there is no integrity between the sheet material, the lower ground, and the upper sand;
When urethane is injected as a foam, the phenomenon of sheet lifting also occurs. In addition, in the method (4), since the injection is carried out inside the formwork, it takes time to install and remove the formwork, and it also has the problem of not being able to handle cases where the cross-section of the embankment is uneven and complex. There was a point.

〔the purpose〕

The present invention solves these problems and provides a lightweight embankment construction method that improves the integrity between the foamed plastic layer and the ground.

〔composition〕

The present invention relates to a lightweight embankment construction method characterized by forming a polyurethane coating layer in advance on the ground surface on the lower and/or side surfaces, and forming a polyurethane foam layer on the upper and/or side surfaces thereof.

As a component for forming a polyurethane coating layer, a coating layer can be formed by applying a paint grade or floor waterproofing grade polyurethane coating material to the ground surface by means such as spraying. . In particular, it is preferable to use a one-component moisture-curing urethane primer.

The formation of the polyurethane foam layer uses conventional foam-in-place polyurethane forming components. Generally, the use of rigid polyurethane-forming components is preferred.

Generally, methods for forming the superstructure of a polyurethane foam layer include: (1) using a reinforced concrete floor plate, (2) laying soil and paving the sidewalk on top of it, and (3) using an iron plate as the floor plate. There are methods.

〔Example〕

Example 1 For a private road, a lightweight embankment method was adopted as shown in Figure 1.

After digging a driveway as shown in Figure 1 and filling the center of the road with sand 2, a layer of polyurethane coating 3 is applied to the ground 1 dug in the shape of a boat bottom. ).

The properties and performance of Praiazotsu T-117 are shown in Table 1 below.
and as shown in Table-2.

Table 1: Properties of Priazotsu T-117 (bubble) manufactured by Co., Ltd.
HM-6161 or HM-6166 manufactured by Inoaraku Corporation. Its physical properties are shown in Table-3.

(Leaving space below) Table-2 Performance of Pryazotsuk T-117 1" 3ml film thickness with iron plate base, finger tact method tack free time *2 mortar (cement/Toyoura standard sand/ion exchange water = 1731
0.5 (mit) 3tieek room temperature curing) depending on the substrate.

” 3ml film thickness, sample after /week room temperature curing Note: Adeka Bontiter HUX-232 (non-yellowing type, low viscosity, stable colloidal dispersion type water-based urethane resin product name) was used instead of Priazotsu T-117 (product name). ) can be used.

Foamed urethane used for urethane embankment 4 (Independent Table 3) A concrete floor plate 5, crushed stone 6, and asphalt layer 7 were constructed on the polyurethane foam embankment 4 thus formed.

Example 2 The above-mentioned curing urethane primer, Pryazoc T-117, was spray-coated on the slope shown in Figure 2, and a retaining wall was constructed using concrete plates. The foamed urethane shown was injection molded. Finally, a concrete floor plate was placed between the retaining wall and the slope on top of the polyurethane foam, soil was laid on top of that, and turf was spread to complete the reinforcement work on the slope.

Since the polyurethane foam layer does not have water permeability, drainage passages are provided along the slope at intervals of about 2 m toward the slope 11 in order to drain rainwater flowing along the slope 11. A drainage system called a hechimanet is usually used for the drainage passage.

The loofah net is a drainage 8f made by wrapping open-cell polyurethane in a sheet! Through this, rainwater reaches the lower gravel layer 2' and is drained from there by a drainage pipe 8. On the other hand, the retaining wall is supported by retaining wall struts 12, and the struts 12 are reinforced by being connected to the slope 11 by anchors 9.

〔effect〕

By using a polyurethane coating layer, the present invention (i) enhances the adhesion to the ground and strengthens the adhesion to the foamed polyurethane embankment layer.

(ii) Waterproofness was significantly improved.

(iii) Work efficiency was improved due to rapid curing at room temperature.

Furthermore, since polyurethane foam was used as the foam layer, (iv) the adhesion and adhesion with the polyurethane coating layer formed on the ground surface were significantly improved.

(V) Since foaming can be performed on-site, it is possible to reduce transportation costs, improve work efficiency, and shorten the construction period.

(vl) The road surface was prevented from freezing.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing an example of construction of a private road in Example 1, and FIG. 2 is a cross-sectional view showing a construction example of the embankment construction method on a steep slope. 1. Ground 2. Sand 2'... Sand 3. Polyurethane coating 4.
・Urethane foam embankment 5 ・Concrete floor plate 6 ・ Crushed stone 7 ・ Asphalt layer 8 ・
Drainage pipe 9...Anchor 10...Sod
11-... Slanted surface 12... Retaining wall prop patent applicant: 2 people other than INOAC Construction Co., Ltd.

Claims (1)

[Claims] 1. A lightweight embankment construction method characterized by forming a polyurethane coating layer in advance on the ground surface at the bottom and/or sides, and forming a polyurethane foam layer on the top and/or sides.