KR20080045600A - Tube with plastic vertical drain and method of soft soil consolidation using tube with plastic vertical drain - Google Patents

Abstract

A plastic vertical drain with a tube and an improvement method of the soft ground are provided to improve problems such as the lowering or loss of discharge capacity by installing a plastic vertical drain with a tube in the earth and draining off water through the tube, to cut down on the cost by draining off water through a tube and utilizing air pressure as load, and to shorten a period of consolidation by draining off water rapidly, compared with natural drainage by banking load. A plastic vertical drain(30) is formed by adding a tube(40) to the inside or the outside of a filter(10b) of the existing plastic vertical drain, wherein the bottom of the tube is made of a filter(40a) for a tube preventing the inflow of soil particles and securing drainage efficiency. An improvement method of the soft ground comprises the steps of: mounting a mandrel shoe(20) to the end of a plastic vertical drain added with a tube, and penetrating the plastic drain added with the tube in the earth to the prescribed depth using a casing, and then pulling up the casing, thereby making the plastic vertical drain stay in the earth; and connecting the tube of the plastic vertical drain to a drain pipe(40b) above the ground, and making the drain pipe face a water collecting well(80) and generating negative pressure to the tube, and draining off underground water through the tube added to the plastic vertical drain.

Description

Tube with plastic vertical drain and method of soft soil consolidation using tube with plastic vertical drain

1 is a plan view showing a conventional belt-shaped plastic vertical drainage (PBD),

Figure 2 is a plan view showing a conventional cylindrical plastic drainage material (PBD),

Figure 3 is a cross-sectional view conceptually showing a soft ground improvement method using a conventional plastic vertical drainage,

Figure 4 is a plan view showing a plastic vertical drainage to which the tube is added to the outside of the filter of the conventional plastic vertical drainage according to an embodiment of the present invention,

Figure 5 is a plan view showing a plastic vertical drainage to which the tube is added in the filter of the conventional plastic vertical drainage according to an embodiment of the present invention,

FIG. 6 is a side view illustrating a bottom filter of a tube and a bottom filter of a conventional plastic drainage pipe prior to penetration into the ground according to the embodiment of FIG. 4; FIG.

Figure 7 is a cross-sectional view conceptually showing a soft ground improvement method for draining water through the tube of the plastic vertical drainage to which the tube is added according to an embodiment of the present invention.

* Explanation of symbols for main parts of drawings *

10: plastic vertical drainage 10a: core

10b: filter 20: mandrel shoe (anchor)

30: plastic vertical drainage material with tube 40: tube 40a: tube filter 40b: drain pipe

50: groundwater level 51: flow of water in the soil

52: flow of water through core

53: flow of water through the tube 70: drainage pump

80: sump h: chicken pox tea

The present invention relates to a plastic vertical drainage and a soft ground improvement method to which the tube is added. More specifically, in the soft ground improvement method, a plastic vertical drainage in which a tube is added to a conventional plastic vertical drainage used in the vertical drainage method is installed in the ground, and water is drained through the tube. It improves the problem that the water supply capacity is reduced or lost due to bending and cutting due to the construction of drainage material, and generates negative pressure in the tube added to the siphon head difference or the drainage pump and drains water through the added tube to reload the atmospheric pressure. It is possible to reduce the thickness of the fill by reducing the thickness of the fill, and to drain it faster than the natural drain due to the fill load. Therefore, the plastic vertical drainage with the added tube to shorten the consolidation period and the soft ground improvement method using the same will be.

Many construction projects are currently underway on very fragile cohesive soils in coastal, riverside and river basins. These compressible viscous soils are grounds such as natural alluvial soils and landfills, and their common characteristics cause excessive settlement when load is applied, and there is a stability problem that shear failure occurs due to weak shear strength. Therefore, in order to ensure the stability of the structure on the soft ground, the first priority is to settle the soft ground so that no additional ground settlement occurs after construction. The most widely used method for consolidating the ground is a preloading method which advances the consolidation settlement of the target structure in advance by preloading the same load as the target structure, but a lot of time is required to consolidate the ground using the preceding loading method. It takes Therefore, the vertical drain method is currently used for the settlement of soft ground.

In the vertical drainage method, various types of drain materials have been developed and used, but the principles thereof are the same, and the present invention is a plastic vertical drainage material, that is, plastic board drain (PBD). Alternatively, it is called prefabricated vertical drain (PVD).

1 and 2 are plan views showing a conventional strip-shaped and cylindrical plastic vertical drainage material (PBD).

The plastic vertical drainage (10) is generated from the clay to act as a drainage for flowing water entering the vertical drainage to the drainage layer to guide the water (10a) and the water exiting from the clay to the drainage to prevent the inflow of the granules Consisting of a filter (10b) to ensure the drainage performance and as shown in Figure 1, the strip-shaped plastic vertical drainage is typically made of a band shape of 100mm width, 3mm thickness of the core (10a) and 2 and Likewise, in the cylindrical plastic vertical drainage material, the core 10a has a hole in the core 10a in a cylindrical shape. As such, the shape and size of the core 10a are manufactured in various ways, and the material and size of the filter also vary.

3 is a cross-sectional view conceptually showing a soft ground improvement method using a conventional plastic vertical drainage (10).

Considering the depth to install the plastic vertical drainage (10) to prepare a casing in the indenter and connect the plastic vertical drainage (10) prepared in roll form with the casing to mount the mandrel shoe 20 at the end of the plastic vertical drainage (10) Then, the plastic vertical drainage 10 is installed in the ground like a casing in the injector, and after pouring to a prescribed depth, the plastic vertical drainage 10 remains in the ground when the casing is drawn out. At this time, the plastic vertical drainage (10) of the ground portion is cut off, the plastic vertical drainage (10) pillars are formed in this manner, and repeated construction and filling on it to generate excess pore water pressure in the soil so that the water in the clay flows horizontally ( 51) The plastic vertical drainage (10) enters and is drained to the ground surface, wherein the plastic vertical drainage (10) is composed of a filter (10b) to prevent the inflow of the core (10a) and the soil particles from the outside and to pass only the water and the filter ( Water entering through 10b) is drained to the ground surface through the core 10a to promote consolidation.

However, the soft ground improvement method using the plastic vertical drainage material (10) is constructed in this way is cut in the middle of the construction of the plastic vertical material reinforcement (10) as a penetrator, or the ground is moved or settled due to the fillet plastic vertical When the drainage is bent, the flow of pore water in the drainage is disturbed. This is called water resistance, and water resistance can delay consolidation by suppressing the discharge of water, and clay in the water is attached inside the vertical drainage, It becomes small and becomes difficult to drain through the core 10a. In addition, the excess pore water pressure is generated by the filling load, and the excess pore water pressure is made through the filling of the appropriate thickness, so the filling cost is incurred.

Therefore, the present invention is to solve such a conventional problem, by installing a plastic vertical drainage in the form of adding a tube to the conventional plastic vertical drainage used in the soft ground improvement method in the ground, so that water is drained through the tube It improves the problem of deterioration or loss of water supply capacity due to the bending and cutting of the conventional plastic vertical drainage, and generates negative pressure in the tube added by the siphon head difference or the drainage pump to drain the water through the added tube. By using atmospheric pressure as a reload, it reduces the thickness of the fill and thus reduces the cost and drains faster than the natural drainage due to the fill load. The purpose is to provide a ground improvement method.

In order to achieve the above object, the present invention provides a plastic vertical drainage and soft ground improvement method, the tube is added, characterized in that the tube is added to the conventional plastic vertical drainage in the soft ground improvement method.

The bottom of the tube is preferably formed with a filter to prevent the inflow of soil and to drain only water.

In addition, the step of injecting the plastic vertical drainage to which the tube is added to the ground; It provides a soft ground improvement method using a plastic vertical drainage material is added to the tube comprising the step of draining the ground water through the tube.

In addition, the plastic vertical drainage is produced in a variety of shapes and sizes, and the material and specifications of the filter is also various, but most of the core (10a) and the filter (10b) structure is usually made, the present invention of the filter (10b) If the plastic vertical drainage 10 that can add the tube 40 to the inside or outside is applicable to both.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. First of all, in adding reference numerals to the components of each drawing, it should be noted that the same reference numerals are used to refer to the same components even though they are shown in different drawings. In addition, in describing the present invention, when it is determined that the detailed description of the related well-known configuration or function may obscure the gist of the present invention, the detailed description thereof will be omitted.

4 and 5 are a plan view showing a plastic vertical drainage in which a tube is added to the outside or inside of the filter 10b of the conventional plastic vertical drainage 10 according to an embodiment of the present invention.

As shown in Figure 4, the plastic vertical drainage to which the tube is added, the conventional plastic vertical drainage 10 in the form of the tube 40 is added to the outside of the filter (10b) of the conventional plastic vertical drainage (10). When the tube 40 is added to fix the lower end and formed in the ground with the plastic vertical drainage when intruding into the ground by the casing of the injector.

In addition, as shown in Figure 5, the plastic vertical drainage to which the tube is added is formed in the form of the tube 40 is added to the inside of the filter 10b of the conventional plastic vertical drainage (10).

At this time, the tube 40 of the plastic vertical drainage to which the tube is added is constructed in the same manner as the plastic vertical drainage 10, so the roll shape is preferable, and the existing plastic as a material that is not easily broken or cut when inserted. If it can be used in addition to the vertical drainage 10, all can be used.

The plastic vertical drainage to which such a tube is added may be formed outside the filter 10b of the plastic vertical drainage 10 as shown in FIG. 4 or may be formed inside the filter 10b of the plastic vertical drainage 10 as shown in FIG. 5. In this embodiment, a plastic vertical drainage to which a tube formed outside the filter 10b of the plastic vertical drainage 10 is added will be described as an example.

FIG. 6 is a side view illustrating a bottom filter of a tube with a bottom of a conventional plastic drainage pipe prior to penetration into the ground according to the embodiment of FIG. 4.

As shown in FIG. 6, the tube 40 is added to the outside of the filter 10b of the conventional plastic vertical drainer 10, and the lower end of the added tube 40 prevents inflow of granules to secure drainage performance. The filter is formed as a filter that acts as a filter for the tube (40a), the added tube 40 is formed in the same roll shape as the plastic vertical drainage (10) and mounted with the plastic vertical drainage (10) in the indenter Install the plastic vertical drainage 10 to the mandrel shoe 20 in the same manner as the conventional vertical drainage method and fix the bottom of the tube 40 to be added to the plastic vertical drainage 10 to the plastic vertical drainage 10 By wrapping and injecting into the ground using an injector to form a plastic vertical drainage to which the tube is added so that the water inside the plastic vertical drainage 10 enters the bottom of the tube 40.

FIG. 7 is a cross-sectional view conceptually illustrating a soft ground improvement method for draining water through a tube of a plastic vertical drainer to which a tube is added according to an embodiment of the present invention.

As shown in FIG. 7, the plastic vertical drainage 30 having the tube 40 added to the inside or the outside of the filter 10b of the conventional plastic drainage 10 is introduced into the ground in the same manner as the conventional vertical drainage method. To form, the lower end of the tube 40 is formed of a filter for the tube (40a) that serves to secure the drainage performance by preventing the inflow of the granules, the mandrel shoe at the end of the plastic vertical drainage 30 added to the indenter 20, the plastic vertical drainage 30 to which the tube is added to the injector, and the plastic vertical drainage 30 is inserted into the casing, and when the casing is drawn out, the plastic vertical drainage 30 remains in the ground. At this time, when the plastic vertical drainage 30 is added to the tube of the ground portion is formed, the plastic vertical drainage 30 pillars are formed in this manner repeated construction and the tube 40 of the plastic vertical drainage 30 in the ground portion Connected to the drain pipe 40b, the drain pipe 40b is directed to the sump 80, and generates negative pressure in the tube added to the siphon water level difference or the drain pump to add the tube of the plastic vertical drainage 30 to which the tube is added. Drain the water through 40.

The negative pressure means a pressure lower than atmospheric pressure as a concept opposite to the positive pressure. The present invention generates a negative pressure in the tube through the drain pipe (40b) connected to the tube in a way to back the water of the tube, the water in the soil flows to the plastic vertical drainage 30 to the tube (51), the plastic vertical Water inside the drain 30 flows to the lower end of the tube 40 through the core 10a (52), and the water collected at the lower end of the tube 40 passes through the drain pipe (40b) along the tube (40). Flowing to (80) (53), the water collected in the sump (80) improves the soft ground while draining by using the drain pump (70).

In addition, since the negative pressure is generated to drain the water in the ground, the atmospheric pressure can be utilized as a reload, thereby reducing the fill thickness, thereby reducing the cost and draining at a higher speed than the natural drainage due to the fill load, thereby shortening the consolidation period. have.

In addition, the lower end of the tube 40 is formed of a tube filter 40a that serves to secure the drainage performance by preventing the inflow of the granules, the tube filter 40a is a tube that is added because various materials are conventionally used What is necessary is just to form in an appropriate shape according to the size of 40, What is necessary is just a shape and shape which can be constructed by the conventional vertical drainage method using the plastic vertical drainage material 30 to which the tube was added.

The above description is merely illustrative of the technical idea of the present invention, and those skilled in the art to which the present invention pertains may make various modifications and changes without departing from the essential specifics of the present invention. Therefore, the embodiments disclosed in the present invention are not intended to limit the technical idea of the present invention but to describe the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The scope of protection of the present invention should be interpreted by the following claims, and all technical ideas falling within the scope of the present invention should be construed as being included in the scope of the present invention.

As described above, according to the present invention, the tube is installed in the form of adding a tube to the conventional plastic vertical drainage used in the soft ground improvement method, and water is drained through the tube, so that the construction of the conventional plastic vertical drainage It improves the problem of lowering or loss of water supply capacity due to bending and cutting that may occur, and generating excess pore water pressure to generate negative pressure with the siphon head difference or drainage pump to drain water through the tube added from the bottom of the ground. By utilizing atmospheric pressure as a reload, the fill thickness can be reduced, reducing costs and draining faster than the natural drainage due to the fill load, thereby reducing the consolidation period.

Claims (3)

In soft ground improvement method, Plastic vertical drainage to which the tube is added, characterized in that the tube is added to the conventional plastic vertical drainage used in the vertical drainage method. The method according to claim 1, The bottom of the tube is a plastic vertical drainage added to the tube, characterized in that to form a filter to prevent the inflow of soil and drain only water. Injecting the plastic vertical drainage to which the tube is added to the ground; Soft ground improvement method using a plastic vertical drainage material is added to the tube comprising the step of draining the ground water through the tube.

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