JP2000186320A - Surface treatment method for soft ground - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a surface treatment method for a soft ground by using soft mud collected by dredging or the like in the vicinity of a landfill or soft mud collected in the landfill. SOLUTION: Soft mud in a landfill is collected, and subjected to an intra-tube mixing solidifying treatment inclusive of using a solidifying material filling device 26 and a intra-tube kneading apparatus 28 which are attached to an air pumping conduit 24. The resultant solidifying material mixed mud is pumped to a destination by using compressed air from an air compressor 29. Before dissemination of the solidifying material mixed mud, a net is laid over the entire area of the soft ground to be disseminated. At this time, in order to form a gap between the mud surface and the laid net, a spacer 36 is arranged at suitable intervals at the time of laying the net. Then, the solidifying material mixed mud which has been pumped is disseminated over the net while a dissemination port at the front end of the pumping conduit 24 being fluctuated rightward and leftward.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a surface treatment method for soft ground, and more particularly to a surface treatment method for soft ground using solidified mud.

[0002]

2. Description of the Related Art In order to effectively use soft ground often found in landfills as land, it is necessary to upgrade the ground to a solid ground.

Prior to such an improvement, it is required to build a base for enabling a heavy machine or the like to be carried in.

As a construction method that meets such a demand, there is a construction method in which a net (resin net or fiber net) having a moderate rigidity and a mesh structure is laid on soft ground to form a covered ground.

FIG. 1 shows a cross section of a base constructed by such a method. A net 12 is laid on the soft ground 10 by manpower or a machine, and sandy soil is sprinkled on the net 12 by a direct drilling method or a water transport method.

[0006]

In the above-mentioned conventional method, since the sandy soil is scattered on the net, when the sandy soil is not near the landfill, the sandy soil must be carried from a distant place. In order to withstand the weight of heavy machinery, the thickness of the sandy soil must be increased. Therefore, there was an economic problem that the cost was high.

An object of the present invention is to provide a surface treatment method for soft ground using soft mud collected near a landfill by dredging or the like or soft mud collected at a landfill.

[0008]

Means for Solving the Problems The surface treatment method for soft ground according to the present invention is based on a method of collecting on-site soft mud in a soft landfill where it is difficult to carry in heavy machinery, etc., and mixing and solidifying in a pipe.
This is a method for forming a solidified ground by using a local soft mud to form a solidified ground by using a local soft mud to spread the water by spraying it to a target area (soft ground) in a landfill where a net has been laid in advance. Things.

According to the surface treatment method of the soft ground of the present invention, since the local mud is used for the improvement of the surface layer of the soft landfill, etc., it is possible to form the solidified ground which is excellent in economy and uniform.

[0010]

FIG. 2 is a view for explaining a surface treatment method for soft ground according to the present invention. Part A of FIG.
Detailed views of B and C are shown in FIGS.

The construction procedure of the construction method will be described below. (1) The soft mud 22 at the site is sampled by a screw conveyor, a mono pump, etc. (the mono pump 20 in the example of FIG. 3), and a solidifying material injection device 26 (cement, lime, etc. is slurried or powdered) attached to the air pressure pipeline 24. The solidified mixed mud is conveyed to the destination by compressed air from the air compressor 29 by the in-pipe mixing and solidifying method including the in-pipe kneading device 28.

The screw conveyor, the MONO pump, etc.
As shown in FIG. 3, these are mounted on a lightweight barge 30 or the like having a structure capable of moving in the lateral direction, and the barge itself is towed from the opposite shore by a winch 32 and moved. (2) Prior to spraying the solidified-material mixed mud, a net 34 having a mesh size of 5 to 30 mm is laid on the soft ground 10 over the entire area at the spraying destination. The net is made of, for example, polyester or polyethylene, and is laid manually. As the net, not only such a resin net but also a fiber net can be used.

At this time, since it is necessary to provide a gap between the mud surface and the laying net, as shown in FIG. 4, spacers 36 made of urethane or styrofoam are provided at appropriate intervals when laying. (3) The solidified-material-mixed mud 38 that has been pressure-fed is sprayed on the net 34 while swinging the spray port at the tip of the pressure-feeding pipeline 24 right and left as shown in FIG. The solidified-material-mixed mud enters the gap formed between the mud surface and the net formed by the spacer 36, and the net 34 is wrapped in the lower part of the scattered mud. (4) The pressure feed pipe 24 is made of a lightweight PVC pipe, is laid on the ground where dispersion of the solidified material mixed mud is completed, and is sequentially extended by manpower or the like to complete the planned area.

[0014]

The surface treatment method for soft ground according to the present invention includes:
There are the following advantages. (1) Since the solidified-material-mixed mud sprayed with a uniform thickness is solidified while wrapping the net in the lower layer, a strong ground is formed. (2) When a heavy machine or the like travels on the solidified mud layer, the tension of the solidified mud layer and the net interact with each other, so that a high supporting force is obtained and heavy machine traveling becomes possible. (3) Since the soft mud near the landfill is collected and used, the soft mud can be recycled, and it is not necessary to carry the soft mud from a remote place unlike the conventional sandy soil, so that the cost of the construction method can be reduced. (4) Since the unit weight of the solidified mud is smaller than that of sandy soil, it can be sprayed more safely than when sandy soil is scattered on soft ground.

[Brief description of the drawings]

FIG. 1 is a view showing a cross section of a base constructed by a conventional method.

FIG. 2 is a view for explaining a surface treatment method for soft ground according to the present invention.

FIG. 3 is a detailed view of a part for collecting mud;

FIG. 4 is a diagram for explaining laying of a net.

FIG. 5 is a diagram showing a state of a solidified-material mixed mud.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Soft ground 12,34 Net 22 Soft mud 24 Pneumatic feeding line 26 Solidified mixed mud 28 Pipe kneading device 29 Air compressor 30 Barge 32 Winch 36 Spacer 38 Solidified mixed mud

 ──────────────────────────────────────────────────続 き Continued on front page (72) Inventor Kenji Kitazawa 1-3-2 Kitaaoyama, Minato-ku, Tokyo Saeki Construction Industry Co., Ltd. (72) Inventor Hiroshi Nishihata 1-2-3 Kitaaoyama, Minato-ku, Tokyo F-term in Saeki Construction Industry Co., Ltd. (reference) 2D043 CA08 DD01

Claims (5)

[Claims] 1. A resin or fiber net is laid at a predetermined interval from the surface of the soft ground, and a mud mixed with a solidifying material is sprayed on the resin or fiber net, so that the resin or the fiber net is wrapped in the lower part of the sprayed mud. A surface treatment method for soft ground, characterized in that a solidified ground is formed in a wet state. 2. The soft ground surface treatment method according to claim 1, wherein said resin or fiber net is held at a predetermined distance from the surface of said soft ground by a spacer. 3. The method of claim 2, wherein the spacer is made of urethane or styrene foam. 4. The method for surface treatment of soft ground according to claim 1, wherein the kneading of the solidified material is performed by an in-pipe kneading device. 5. The method for surface treatment of soft ground according to claim 1, wherein the mud is obtained by collecting mud at the site.