JP2004137778A - Surface layer treatment method for soft ground and its device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a surface layer treatment method for the soft ground by the use of a flexible planar reinforcing member such as sheet and a net to give rigidity to the flexible planar reinforcing member by a comparatively simple rigid reinforcing body and install the rigid reinforcing body on the soft ground easily at a low cost. <P>SOLUTION: The flexible planar reinforcing member 11 such as sheet and a net is provided on the soft ground 1. A flexible linear hollow body 13 composed of a hose having dewaterbility and high tensile strength is arranged or attached in advance on at least either of the upper face and the lower face of the planar reinforcing member 11. Mortar 14 is filled into the linear hollow body 13 to form the lattice-like rigid reinforcing body 12. The load of sediment loaded through the planar reinforcing member 11 is dispersed by the rigid reinforcing body 12 having a frame structure allowing easy istallation and having high rigidity, and the destruction and deformation of the soft ground are suppressed to perform stable sediment work such as soil covering and filling. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method and apparatus for processing a surface layer of a soft ground for laying a flexible planar reinforcing material such as a sheet or a net on a soft ground such as a cohesive soil to construct a soil covering or an earth structure. It is about.
[0002]
[Prior art]
When soil is directly scattered on the soft ground of cohesive soil, depending on the load of sediment or the weight of the dispersing machine, the soil may mix with the cohesive soil and become useless, or the ground may collapse and collapse. .
[0003]
In order to prevent such a phenomenon, a sheet method using a woven fabric made of fiber as an laying material was invented in 1966, and then a laying net method using a synthetic resin net as the laying material was developed (for example, Patent Document 1). Several related methods have been developed, such as a rope sheet method that aims to reinforce the sheet, or a method that combines a bamboo frame with a sheet or net.
[0004]
In addition, a solidification treatment technique for stabilizing a surface layer portion by adding and mixing a solidifying material such as cement to soft soil has been developed. Furthermore, as a technology for improving the surface of soft ground on land or under water, a bag of a large area of permeable geotextile made of a material with tough and tensile strength is deployed on the surface of soft ground and poorly mixed in this bag. There has been proposed a method of forming a flat solidified layer in which a solidified material such as a cement type is filled and the hardened solidified material is integrally covered with a bag having tensile strength (for example, see Patent Document 2). .
[0005]
[Patent Document 1]
JP 2002-227178 A [Patent Document 2]
JP-A-11-152735
[Problems to be solved by the invention]
The key to the success of the method of laying flexible planar reinforcing materials such as sheets and nets is the method of dispersing earth and sand. The point is that uneven settlement due to uneven embankment thickness and local settlement is not caused as much as possible. As shown in FIG. If a habit of sinking is given, it becomes difficult to correct the non-uniform state in the subsequent second layer spraying.
[0007]
For this reason, as shown in FIG. 5, various measures have been taken, such as jetting with a jet conveyor and water carrying using a dredge pump. However, once a dent is formed, it will promote the concentration of local settlement. It becomes difficult to control and adjust the sand thickness.
[0008]
Such a problem cannot be prevented if the tensile strength of the sheet or the net is a little large, but cannot be basically prevented unless the material to be laid is given rigidity and exerts a load dispersing effect. The principle of the construction method of assembling bamboo with a length of several meters in a grid of 1 m intervals and laying a sheet on it is just to exert the load distribution effect, but procurement of bamboo, formation of bamboo frame, softness There is a problem of workability related to installation on the ground.
[0009]
On the other hand, there has been an attempt to directly solidify the soft ground surface layer in a lattice shape with cement or the like to expect a bamboo frame effect, but the number of separate steps is increased and the cost is high. Also, the method of solidifying the entire surface layer or the method of filling a large bag with a cement-based solidifying material in a large bag is more expensive than the method of laying a sheet or a net.
[0010]
The present invention has been made to solve such a problem, and in a surface treatment method for soft ground using a flexible planar reinforcing material such as a sheet or a net, a flexible planar reinforcing material is used. It is an object of the present invention to provide a method and an apparatus for treating a surface layer of soft ground, which can provide rigidity by a relatively simple rigid reinforcing body and can lay the rigid reinforcing body on soft ground easily at low cost. .
[0011]
[Means for Solving the Problems]
A first aspect of the present invention is to lay a flexible planar reinforcing material (a sheet, a net, or the like) on soft ground, and to provide a flexible planar reinforcing material on at least one of an upper surface and a lower surface of the planar reinforcing material. A linear hollow body (such as a hose that can be dewatered) is arranged so as to form a surface, and mortars (such as mortar and other cement-based solidifying materials) are filled in the linear hollow body and are lattice-shaped in plan view. A method for treating a surface layer of soft ground characterized by forming a rigid reinforcing body such as
[0012]
According to a third aspect of the present invention, a flexible planar reinforcing material (a sheet, a net, or the like) laid on soft ground and disposed on at least one of an upper surface and a lower surface of the planar reinforcing material. A flexible linear hollow body (such as a dewaterable hose) is filled with mortars (such as mortar and other cement-based solidifying materials) to form a grid-like rigid reinforcing body formed in plan view. It is a surface treatment apparatus for soft ground characterized by being constituted.
[0013]
In other words, assembling in advance a rigid material that spreads the load due to soil covering etc. by giving a surface rigidity to a sheet or a net as a soft ground laying material is preferable as workability when laying on soft ground. Not something. Therefore, at the time of laying, a linear hollow body such as a hose having flexibility as well as a sheet or a net and having good handling is arranged on the lower surface, the upper surface, or both upper and lower surfaces of the sheet or the net, and after the laying, the mortar is provided. By injecting and filling the materials into a linear hollow body such as a hose, a highly rigid framework, that is, a rigid reinforcement body is formed.
[0014]
A linear hollow body such as a hose is previously attached to the upper or lower surface of a sheet-like reinforcing material such as a sheet or a net by a fixing means such as a binding member or an adhesive, and both are simultaneously deployed and laid on soft ground. Alternatively, the linear hollow body may be provided separately from the planar reinforcing material on the soft ground or the planar reinforcing material. In addition, a large number of linear hollow bodies may be arranged at intervals in the vertical and horizontal directions in a plan view, or may be continuous in a waveform or the like in a plan view. The rigidity can be further increased by adding an oblique linear hollow body to a planar reinforcing material such as a lattice in plan view.
[0015]
Further, in the first and third aspects, a hose having water permeability and strength is used for the linear hollow body (claims 2 and 4). For example, using a fiber material having a high tensile strength such as a woven or nonwoven fabric that allows moisture in the mortar to pass but does not allow the solid to pass therethrough, making this into a tubular shape, having a dewatering property, and having a tensile strength of Use a high hose. That is, it is lightweight and easy to handle, and after filling the mortar, only excess water in the mortar permeates, the cured mortar and the hose having high tensile strength are integrated, and a hose having high rigidity is obtained. To do.
[0016]
According to the present invention having the above-described configuration, the following operation and effect can be obtained. In other words, since only sheets or nets laid on soft ground do not have rigidity, unless very careful management is performed for operations such as covering soil, destruction or deformation of soft ground as described above Cannot be avoided (see FIGS. 4 and 5). On the other hand, in the present invention, the mortar is injected into a hose having a lattice shape or the like after the sheet or the net is laid, so that the mortar is further filled into the hose having water permeability and strength and cured. The strength is increased by the tensile reinforcement effect of the hose existing on the outer periphery of the mortar (see FIG. 2), so that a rigid reinforcement body having a highly rigid frame structure is formed, and the earth and sand loaded via a sheet, a net or the like. The load can be dispersed, and the destruction and deformation of the soft ground can be suppressed, and stable earth covering and embankment work can be performed.
[0017]
In addition, assembling a rigid material such as a conventional bamboo frame in advance has poor workability in terms of carrying in or laying, but a flexible linear hollow body such as a hose has good handling, Since it can be rolled up or bent, it is easy to carry it in or lay it on soft ground. Further, in the conventional method using a solidifying material such as cement, the cost increases. However, by filling a mortar into a flexible linear hollow body such as a hose, the rigid reinforcing body has a relatively simple structure. The amount of use of the solidifying material such as cement can be greatly reduced, and the cost can be reduced.
[0018]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described based on the illustrated embodiments. This embodiment is a case where embankment or covering is performed on soft ground. FIG. 1 is a perspective view and a sectional view showing one embodiment of a surface treatment apparatus used in the surface treatment method of the present invention.
[0019]
In the embodiment of FIG. 1, the surface treatment apparatus 10 of the present invention is laid on the soft ground 1 before embankment or covering 2 is performed on the soft ground 1, and is laid on the soft ground 1. A flexible planar reinforcing material 11 and a flat surface formed by filling a mortar 14 into a flexible linear hollow body 13 attached to only the lower surface, only the upper surface, or both upper and lower surfaces of the planar reinforcing material 11 It is composed of a rigid reinforcing body 12 in a lattice shape when viewed.
[0020]
As the flexible planar reinforcing material 11, a commonly used sheet or net made of synthetic resin or the like is used. As the flexible linear hollow body 13, a hose or the like having a high water-permeability and a high tensile strength, which allows moisture in the mortar to permeate but does not allow solids to permeate. As the mortar 14, mortar or other cement-based solidifying material or a material having fluidity and curability is used.
[0021]
When the mortars 14 are filled in the hose 13 as described above, only excess water in the mortars permeates, the hardened mortars 14 and the hose 13 are integrated, and a grid-like rigid reinforcing body 12 having high rigidity is obtained. Can be FIG. 2 is a graph showing the bending strength characteristics of the hose hardened by injecting the mortar 14 into the hose 13, and the strength is increased by the tensile reinforcement effect of the hose existing on the outer periphery of the hardened mortar.
[0022]
FIG. 3 shows the load distribution effect of the present invention. As shown in FIG. 3 (a), when only the flexible planar reinforcing member 11 has no rigidity, the sediment load However, as shown in FIG. 3 (b), the sediment load loaded via the flexible planar reinforcing material 11 is dispersed by the rigid rigid reinforcing body 12 having a high rigidity, and the The amount of land settlement can be greatly reduced, and the stability in embankment work and earth covering work can be improved.
[0023]
At the time of construction, the flexible planar reinforcing material 11 is wound up in a roll shape or the like as in the related art, unwound by an appropriate means such as a hand or a traction device, and deployed and laid on the soft ground 1. The flexible linear hollow body 13 is also wound or folded on a reel or the like, and is disposed on the soft ground 1 or the planar reinforcing material 11. The linear hollow body 13 may be laid as it is, or may be fixed to the planar reinforcing member 11 by a fixing means such as a binding member or an adhesive.
[0024]
In addition, the flexible linear hollow body 13 is previously attached to the flexible planar reinforcing member 11 by a fixing means such as a binding member or an adhesive, and the flexible planar reinforcement is wound into a roll or the like. The material 11 and the lattice-shaped linear hollow body 13 can be rewound and laid at the same time.
[0025]
In addition, in the illustrated example, the linear hollow bodies 13 are arranged vertically and horizontally on the upper and lower surfaces of the planar reinforcing material 11 to form a lattice shape. However, the present invention is not limited thereto, and only the upper surface or only the lower surface of the planar reinforcing material 11 is provided. They may be arranged in a grid or other arrangement methods. If the oblique linear hollow body 13 is added to the lattice arrangement, the rigidity of the rigid reinforcing body 12 can be further increased. In addition, although the linear hollow body 13 arrange | positions many linear things horizontally and vertically, if the pumping distance of a mortar is solved, the linear hollow body 13 will be continuous in a waveform etc. in planar view. It is also possible to arrange.
[0026]
When the laying of the planar reinforcing material 11 and the linear hollow body 13 is completed, the mortars 14 are injected and filled into the linear hollow body 13, and when the mortar 14 is solidified, a working machine or a sand discharging pipe is used. The earth and sand are scattered on the planar reinforcing material 11 and covered with the embankment and the covering soil 2.
[0027]
【The invention's effect】
The present invention has the above-described configuration, and has the following effects.
[0028]
(1) After laying a flexible planar reinforcing material such as a sheet or a net, a mortar is injected into a flexible linear hollow body such as a grid-like hose to further improve water permeability and strength. By filling the mortar inside the hose having the mortar, the strength is increased by the tensile reinforcement effect of the hose present on the outer periphery of the hardened mortar, thereby forming a rigid reinforcement having a highly rigid frame structure, such as a sheet or a net. Can disperse the sediment load imposed on the ground, thereby suppressing the destruction and deformation of the soft ground, and performing stable earth covering work of the embankment and embankment.
[0029]
(2) A flexible linear hollow body such as a hose is easy to handle and can be rolled up or folded, so that it can be easily loaded or laid on soft ground, and imparts rigidity to a sheet or a net. The work of laying the rigid reinforcement can be easily performed at low cost.
[0030]
(3) By filling a mortar into a flexible linear hollow body such as a hose, the rigid reinforcing body can be made to have a relatively simple structure, and the amount of a solidifying material such as cement is greatly reduced. Therefore, cost can be reduced.
[Brief description of the drawings]
FIG. 1 shows one embodiment of a surface treatment apparatus used in a surface treatment method of the present invention, (a) is an overall perspective view, (b) is a cross-sectional view before mortar injection, and (c) is after mortar injection. It is sectional drawing.
FIG. 2 is a schematic front view showing a bending test of the mortar-filled hose of the present invention, and a graph showing the relationship between the load and the amount of displacement.
3A and 3B are cross-sectional views showing deformation states of sheets and the like on soft ground due to earth and sand, where FIG. 3A shows a case where there is no conventional rigidity, and FIG.
FIG. 4 is a cross-sectional view showing local settlement and plastic flow in conventional sheets.
FIG. 5 is a cross-sectional view showing a differential settlement phenomenon in water discharge by a conventional jet or dredging pump.
[Explanation of symbols]
1 Soft ground 2 Embankment or earth covering 10 Surface treatment device 11 Flexible sheet reinforcing material (sheet, net, etc.)
12 ... lattice-shaped rigid reinforcing body 13 ... flexible linear hollow body (dewaterable hose etc.)
14 Mortars (Mortar and other cement-based solidifying materials, etc.)

Claims (4)

A flexible planar reinforcing material is laid on the soft ground, and a flexible linear hollow body is disposed on at least one of the upper surface and the lower surface of the planar reinforcing material so as to form a surface. A method for treating a surface layer of soft ground, characterized in that a mortar is filled in the linear hollow body to form a rigid reinforcing body. The surface treatment method for soft ground according to claim 1, wherein the linear hollow body is a hose having water permeability and strength. A flexible planar reinforcing material laid on soft ground, and a mortar inside a flexible linear hollow body disposed on at least one of the upper surface and the lower surface of the planar reinforcing material. A surface treatment apparatus for soft ground, comprising: a rigid reinforcement body having a lattice shape in plan view formed by filling. 4. The surface treatment apparatus for soft ground according to claim 3, wherein the linear hollow body is a hose having water permeability and strength.

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