JP2571931B2 - Earth covering method using lightweight material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION a. Object of the Invention <Field of Industrial Application> The method of the present invention relates to a technique for performing soil covering on an extremely soft ground such as one buried with dredged soil.

<Conventional technology> Conventionally, a method of covering soil on such an ultra-soft ground is a method in which a surface solidification treatment machine is floated in the ground by a float, and a cement-based soil solidifying agent is discharged to a vicinity of a stirring blade or treated while being discharged. The ground is agitated by rotating and raising and lowering the stirring blades of the machine to form a solidified layer of about several meters in the surface layer of the ground by mixing and mixing, and scatter sand and the like on the solidified layer to perform soil covering work. There are techniques to do.

<Problems to be solved by the invention> By the way, the above-described method has the following problems. That is, (1) In the case of forming a continuous solidified layer by wrapping the respective solidified piles formed in the landfill ground by the rotation of the stirring blades, the wrap between the existing pile and the pile under construction is made. When the solidified layer is formed while moving continuously in the horizontal direction, it is difficult to control the specified layer thickness from the reference depth.

(2) Cracks are easily generated in the formed solidified layer. This can occur due to the passage of time after the formation of the solidified layer, and also due to an uneven load due to the ejection of sand or the like.

(3) When harmful substances are contained in the landfill ground, there is a risk that harmful substances that have calmed down due to agitation of the soil may be lifted up. Such a ground has a water layer on the surface. In many cases, and there is concern about environmental pollution.

Therefore, the method of the present invention does not have the above-mentioned problems,
An object of the present invention is to provide a construction method having a load distribution effect.

B. Configuration of the Invention <Means for Solving the Problems> The method of the present invention has the following constituent requirements in order to achieve the above object.

(1) On the upper and lower surfaces of a thick closed-cell foamed resin molded plate,
A floor material block of a unit formed by laminating reinforcing members is continuously laid on the landfill ground, and connected to each adjacent floor material block via the reinforcing member, and a required amount of embankment is formed on the upper surface thereof. Earth covering method using lightweight materials.

<Effect> In a wide range of land reclamation work by landfilling using dredging mud, etc., ultra-soft ground with no bearing capacity such as water floating on the surface, that is, as construction conditions, (a) The dredged soil has a water content of Is high.

(B) The thickness of the drift water is more than 0.5m from the dredging mud surface.

 In the method of covering the landfill, (i) the mud surface of the dredged soil shall not be exposed to the atmosphere.

(Ii) Wastewater is discharged through sewage treatment facilities.

(Iii) Since the landfill area is large, the above conditions (i) and (ii) are completely satisfied, and the construction is easy and economical.

The following construction methods have been proposed as construction floats requiring dredging → sewage treatment → intermediate partitioning dike → sheet laying → scattered soil → earth covering work.

The construction method of the present invention mainly relates to a new intermediate partition embankment construction technology.

That is, the method of the present invention is lightweight and buoyant, assembles flooring blocks of relatively strong and flexible units in a temporary yard, transports them on the water, makes them land, connects and extends them to each other, The purpose of this project is to create a temporary partitioning road or a temporary road that can pass through a dump truck on the water embanked on the basis of the block, to carry in the soil by land transportation, and to efficiently promote the earth covering on the super soft ground. is there.

Close to landfill and convenient for transporting and collecting materials
Select a place with good scaffolding and set up a temporary yard.In the same yard, in the order from the bottom, slender materials made of materials such as bamboo, wood, or plastic are arranged in a vertical and horizontal lattice, wire-clamped, assembled and unit-sized. A flexible lower net is formed, a plywood of substantially the same shape, same size, and evenness is overlaid on the upper surface, and a sheet material, a thick foamed polystyrene foam-like closed-cell foam synthetic resin material, and an upper surface thereof Then, a lower layer flexible grid net having the same structure as the lower layer net is laminated, and the four sides of the upper and lower layer nets are mutually tightened to assemble the unit of the flooring block.

The assembling of the flooring block is carried out using a place that is convenient for transporting the material and has a good footing, so that the work is efficient, and the required size can be easily assembled.

The foamed synthetic resin material used here has a shape retention property by itself and does not have water absorption, and may be a preformed one by an in-mold foaming method, or may be one by an on-site extrusion molding method. Is also good. It is preferable that the floor material block assembled in the temporary yard is entirely attached to a hanging fitting and lifted and transported in order to prevent the material from being collapsed or deformed due to bending or the like at the time of landing and transporting to the landing point.

The floor material blocks lifted and transported by a truck crane etc. sequentially from the temporary yard descend on the water surface of the landfill,
Connect to and extend existing blocks. At that time, the lateral movement of the foam synthetic resin material at the time of soil covering by fastening the side edge of the floor material block to the pile that has been driven into the ground along the pre-designed landfill division, Prevents separation and dispersion due to uneven load.

The above-mentioned floor material block assembling unit is not more than a certain size, so a floor material block for a trunk part or a separation part of a temporary partition and a temporary road that requires a wide width or a large area is composed of a unit assembling block, After each transportation and landing,
What is necessary is just to join together vertically and horizontally and to form one unit.

In the description above, the flooring blocks were described as if they were transported from the temporary yard by land and transported to a predetermined position.However, if necessary, the blocks can be lifted and transported by a crane ship, or the blocks in assembled units can be transported. It is free to carry on a barge to the required position.

Thus, while the construction of at least a pair of substantially parallel partitioning embankments in the landfill ground progresses, before the embankment for the embankment and temporary road is laid on the surface of the basement material block, A long sheet is stretched over the surface of the landfill area by tying between flooring blocks, and each end of the sheet is overlapped on the upper surface of the flooring block.

The embankment for temporary road development is applied on the sheet, so that both ends of the sheet can be pressed, and the partition wall can be used as an anchor for tension applied to the sheet based on the soil covering operation. In order to anchor the sheet more effectively, a stake is also provided at the end of the sheet.

The vehicle is passed through the intermediary embankment / temporary road and passed through the transport vehicle, and the soft sand for covering is carried in, and the spread soil (sand or a granular material similar to sand) on the spread sheet is treated with sewage. Top-layer embankment work can be performed in one, two or three steps
To cover the entire landfill of ultra-soft ground.

The method of the present invention relates to the above-mentioned construction method, in which a lightweight flooring block is exclusively assembled and fixed in landfill waters, thereby forming a partition and a temporary road construction base. It is a development that has been carried out.

<Example> FIG. 1 shows an example of a flowchart of the method of the present invention, and the work proceeds in parallel with a temporary yard on land and on water.

FIGS. 2 (a) to 2 (e) mainly show the assembling order of the floor material blocks, in which, from the lower layer, (a) 160 bamboo bales of 10φcm × 9m are divided and arranged in a grid pattern vertically and horizontally. A lattice member having a square of 16.4 m on a side is assembled, and the crossing points of the respective materials are fixed to the respective lines to form the lower flexible bamboo net 1 with high flexibility.

(B) The plywoods 2 of the same shape and the same size, which are stapled with each other and formed into a single plate, are stacked on the upper surface of the lower bamboo net 1.

(C) A sheet 3 of the same shape and size is placed on the upper surface.

(D) A material (standard material) 4 made of styrene foam resin 3x6 and having a thickness of 42 cm is laid on the upper surface without any gap.

The general properties of the resin are: (i) density 20 kg / m ³ (ii) compressive strength 1 kg / cm ² (iii) bending strength 3 kg / cm ² (iv) tensile strength 4 kg / cm ² (v) friction coefficient It is preferably about 0.5.

However, it is also possible to use one integrally molded by extrusion foam molding on site.

(E) Upper bamboo net 5 having the same structure as described in (a).
Is stacked on the upper surface of the foamed resin material 4, and the four sides of the upper and lower bamboo nets are fixed to each other by a wire, so that the floor material block is assembled.

It shows the place.

FIG. 3 shows that floor materials blocks assembled and stocked at a temporary yard are suspended at four points by a lifting bracket 6 and transported from a temporary yard to a landfill surface by a truck crane, and then dropped to the surface of the water. The process of connecting to a block is shown. As for the connection of the flooring blocks, as shown in the cross section of the main part in FIG. 4, bamboo nets 1 and 5 at the upper and lower stages are attached with reinforcing bamboos 7 and fastened to each other. The floor material block above the water is wound around the rope from the unit barge and the position is adjusted.

When transporting from the temporary yard and landing on the landing site,
The floor block material is lifted and transported evenly using the hanging metal fittings 6 so that the floor material block material does not collapse or deform due to bending or the like, and the foamed resin material 4 moves laterally or separates due to unbalanced load at the time of soil covering of the landfill. To prevent dispersion,
The upper and lower tiers are held by bamboo nets, and pine piles 8 are provided on the sides to provide a stopper effect.

In this way, the embankment having a predetermined cross section is applied on the floor material block connected to the super soft landfill ground to construct, for example, a partition road and a temporary road having an upper surface width of two lanes of a dump truck.

 FIG. 5 shows a typical sectional structure.

6 (a) to 6 (e) show the construction flow of land preparation work in which the method of the present invention is carried out. (A) Dredging to create a landfill consisting of an ultra-soft ground with a water depth of about 0.5m I do.

(B) The method of the present invention is performed to form an intermediate partition embankment.

(C) A sheet is laid across the landfill between a pair of partition walls, and the partition walls are used as anchors.

(D) Shirasu water carrying method on the sheet is applied.

(E) It explains that construction work is performed in the order of earth covering work.

C. Effects of the Invention As described above, according to the method of the present invention, since the partitioning dike and the temporary road are constructed based on the flexible light-weight floor panel block of the flexible structure, the work is carried out only in a place with good scaffolding. To be able to perform efficiently and easily, and to apply a concentrated load to a buoyant base, to maintain the effect semi-permanently without causing cracks, and to eliminate all the above-mentioned problems inherent in the conventional method It is possible to provide a new earth covering method capable of performing the method.

[Brief description of the drawings]

1 is a construction process of a partition and a temporary road base in the earth covering method according to the present invention, FIG. 2 is an assembly process diagram of a lightweight flooring block, FIG. 3 is a construction diagram of the flooring block, FIG.
FIG. 5 is a cross-sectional view of a connecting portion between floor material blocks, FIG. 5 is a cross-sectional structural view of a partition embankment after construction, and FIG. 6 is a schematic diagram of a landfill ground covering construction process. 1, 5 ... bamboo net, 2 ... plywood, 3 ... sheet, 4 ... foam synthetic resin, 6 ... hanging metal fittings, 7 ... bamboo for reinforcement, 8 ... pile.

Claims (1)

(57) [Claims] 1. A floor material block of a unit formed by laminating a reinforcing member on each of upper and lower surfaces of a thick closed-cell foamed resin molded plate is continuously laid on a landfill ground. A soil covering method using a lightweight material, which comprises applying a required amount of embankment to the upper surface after being connected to a block and its reinforcing member.