KR102620880B1 - tube structure and embankment method using the same - Google Patents

Abstract

A tube structure according to an embodiment includes a plurality of support parts formed in a tube shape; A filling part that fills the inside of the support part; and a coupling part poured into the space formed between the supports formed in multiple stages, wherein the support or filling part allows the inflow or discharge of water, and the coupling part is made of cement, fly ash, sand, silt, quick-setting agent, and The plurality of supports may be joined to each other by including a cement-based binder made of water.

Description

Tube structure and embankment method using the same {tube structure and embankment method using the same}

A tube structure and an embankment method using the tube structure are disclosed.

Geotextiles, a type of geotextile, are woven and non-woven fabrics that are flexible and permeable and generally have a fabric-like appearance. Geotextiles are used for a filtration function that moves water while retaining soil particles and a reinforcing function that improves strength by inducing bonding of soil to unreinforced ground.

These geotextiles are currently being used in civil engineering structures at home and abroad for various functional aspects. For example, geotextile tubes have been used to prevent flooding and coastline erosion caused by hurricanes in New Jersey, USA, to construct the artificial island of Amwaz in Bahrain, and to construct a temporary dam for the construction of a dam in Morocco. Recently, research on the stability of geotextile tubes has been actively conducted when constructing geotextile tubes as drought barriers.

The above-mentioned background technology is possessed or acquired by the inventor in the process of deriving the present invention, and cannot necessarily be said to be known technology disclosed to the general public before the application for the present invention.

Registered Patent Publication No. 10-1427841

The purpose of one embodiment is to provide an embankment with low cost and high stability for the renovation of an agricultural reservoir by using a tube structure made by embanking geotextile tubes in multiple stages and applying a binder.

Using the reservoir dredged soil as the internal filler of the geotextile tube, a multi-stage geotextile tube is built on the ground, and the stability of the structure is improved and the shielding function is promoted during filling.

The problems to be solved in the embodiments are not limited to the problems mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the description below.

A tube structure according to an embodiment for achieving the above object includes a plurality of support parts formed in a tube shape; A filling part that fills the inside of the support part; and a coupling part poured into the space formed between the supports formed in multiple stages, wherein the support or filling part allows the inflow or discharge of water, and the coupling part is made of cement, fly ash, sand, silt, quick-setting agent, and The plurality of supports may be joined to each other by including a cement-based binder made of water.

According to one side, based on 100 parts by weight of the cement-based binder, 15 to 17 parts by weight of the cement; 12 to 13 parts by weight of the fly ash; 30 to 33 parts by weight of the sand; 12 to 13 parts by weight of the silt; 0.5 to 1 part by weight of the quick-setting agent; and 25 to 26 parts by weight of water.

According to one side, the support part is a geotextile tube manufactured in a cylindrical shape, and the filling part may include dredged soil.

An embankment method using a tube structure according to an embodiment to achieve the above object includes providing a plurality of tubular supports; Filling the inside of the support part with a filling part; forming a first support layer by disposing a plurality of the support parts on the ground; Casting a joint portion in a space formed between adjacent supports in the first support layer; and forming a second support layer by stacking a plurality of support parts on the first support layer.

According to one side, the coupling unit includes a cement-based binder composed of cement, fly ash, sand, silt, quick-setting agent, and water, and further includes curing the binder after forming the second support layer, The first stage and the second support layer may be bonded to each other using the binder.

According to one side, based on 100 parts by weight of the cement-based binder, 15 to 17 parts by weight of the cement; 12 to 13 parts by weight of the fly ash; 30 to 33 parts by weight of the sand; 12 to 13 parts by weight of the silt; 0.5 to 1 part by weight of the quick-setting agent; and 25 to 26 parts by weight of water.

According to one side, the support part may be a geotextile tube manufactured in a cylindrical shape.

According to the tube structure according to one embodiment, there is an effect of providing an embankment with low cost and high stability for the renovation of an agricultural reservoir by using a tube structure in which geotextile tubes are filled in multiple stages and applying a binder.

According to the tube structure according to one embodiment, the reservoir dredged soil is used as an internal filler of the geotextile tube to fill the multi-stage geotextile tube on the ground, and the stability of the structure is improved and the shielding function is promoted during the fill.

The effects of the tube structure according to one embodiment are not limited to those mentioned above, and other effects not mentioned may be clearly understood by those skilled in the art from the description below.

1 schematically shows a tube structure according to one embodiment.
Figure 2 schematically shows a tube structure composed of a first support layer and a second support layer.
Figures 3a to 3c show graphs showing the change in strength of the tube structure depending on the presence or absence of a coupling portion.
Figure 4 shows an embankment method using a tube structure according to one embodiment.
The following drawings attached to this specification illustrate a preferred embodiment of the present invention, and serve to further understand the technical idea of the present invention along with the detailed description of the invention, so the present invention is limited to the matters described in such drawings. It should not be interpreted in a limited way.

Hereinafter, embodiments will be described in detail through exemplary drawings. When adding reference numerals to components in each drawing, it should be noted that identical components are given the same reference numerals as much as possible even if they are shown in different drawings. Additionally, when describing an embodiment, if a detailed description of a related known configuration or function is judged to impede understanding of the embodiment, the detailed description will be omitted.

Additionally, in describing the components of the embodiment, terms such as first, second, A, B, (a), and (b) may be used. These terms are only used to distinguish the component from other components, and the nature, sequence, or order of the component is not limited by the term. When a component is described as being "connected," "coupled," or "connected" to another component, that component may be directly connected or connected to that other component, but there is no need for another component between each component. It should be understood that may be “connected,” “combined,” or “connected.”

Components included in one embodiment and components including common functions will be described using the same names in other embodiments. Unless stated to the contrary, the description given in one embodiment may be applied to other embodiments, and detailed description will be omitted to the extent of overlap.

Figure 1 schematically shows a tube structure 10 according to one embodiment.

Figure 2 schematically shows a tube structure 10 composed of a first support layer (L1) and a second support layer (L2).

Referring to FIG. 1, the tube structure 10 according to one embodiment may include a support part 100, a filling part 200, and a coupling part 300.

Specifically, the support part 100 may be formed in a tube shape. A plurality of support units 100 may be provided. The support 100 may be, for example, a geotextile tube manufactured in a circular or oval shape. These supports 100 may be stacked in multiple stages from the ground as shown in FIG. 2 . The support 100 made of geotextile may have flexibility and permeability.

The filling part 200 may fill the inside of the support part 100. The filling portion 200 may include dredged soil. This filling portion 200 may allow water to enter or exit. That is, the tube structure 10 according to one embodiment can move water while maintaining soil particles by using the support part 100 and the filling part 200.

As described above, the tube structure 10 according to one embodiment can be used as an embankment to prevent erosion by stacking geotextile tubes filled with dredged soil therein in multiple stages.

Referring to FIG. 2, the plurality of support parts 100 disposed from the ground may form a first support layer (L1) or a second support layer (L2).

According to one embodiment, the first support layer L1 may be a plurality of support parts 100 arranged on the ground. For example, the first support layer L1 may be formed by arranging the support part 100' and the support part 100'' among the plurality of support parts 100 on the ground.

According to one embodiment, the second support layer (L2) may be a plurality of support parts 100 stacked on the first support layer (L1). For example, the second support layer (L2) may be formed by arranging the support portion (100''') on the first support layer (L1) so as to contact both the support portion (100)' and the support portion (100'').

In Figure 2, the first support layer (L1) is shown as consisting of two support parts (100', 100'') and the second support layer (L2) as consisting of one support part (100'''), but the first support layer ( L1) and the second support layer (L2) may be composed of two or more supports depending on the size or height of the tube structure 10. In addition, the tube structure 10 includes not only a first support layer (L1) and a second support layer (L2), but also a third support layer, a fourth support layer, and a fifth support layer composed of a plurality of support parts 100 as shown in FIG. 1. , … It may further include the like.

For example, the tube structure 10 according to one embodiment installed as an embankment may be installed in a river, coast, lake, swamp, etc., and a horizontal force due to the movement of water may be applied to the tube structure 10.

At this time, the coupling portion 300 may be poured to increase friction between the plurality of support portions 100. As shown in Figures 1 and 2, when a plurality of support parts 100 are piled in multiple stages, an empty space may be formed between the support parts 100 due to the shape of the support parts 100.

The coupling portion 300 may be cast in the space formed between the plurality of support portions 100 that are filled in multiple stages as described above. This coupling portion 300 can increase the overall stability of the tube structure 10 by coupling the plurality of support portions 100 to each other.

Specifically, the coupling portion 300 may include a cement-based binder. For example, the joint 300 may be a cement-based grout material.

The tube structure 10 according to one embodiment may be dismantled after temporary installation, for example, like a fence. That is, the tube structure 10 according to one embodiment must have high fluidity to fill the space between the supports 100, and must have strength according to the curing time as well as adhesiveness for combining the supports 100, and at the same time, It is necessary to include a coupling portion 300 with appropriate strength depending on whether it is released or not.

Accordingly, the coupling portion 300 may be composed of, for example, cement, fly ash, sand, silt, quick-setting agent, and water. Additionally, the materials may be included in an optimal composition ratio for the above-described coupling portion 300 with high fluidity, adhesion, and strength.

According to one embodiment, cement may be included in an amount of 15 to 17 parts by weight based on 100 parts by weight of the cement-based binder.

According to one embodiment, fly ash may be included in an amount of 12 to 13 parts by weight based on 100 parts by weight of the cement-based binder.

According to one embodiment, sand may be included in an amount of 30 to 33 parts by weight based on 100 parts by weight of the cement-based binder.

According to one embodiment, silt may be included in an amount of 12 to 13 parts by weight based on 100 parts by weight of the cement-based binder.

According to one embodiment, the quick setting agent may be included in an amount of 0.5 to 1 part by weight based on 100 parts by weight of the cement-based binder.

According to one embodiment, water may be included in an amount of 25 to 26 parts by weight based on 100 parts by weight of the cement-based binder.

Depending on the presence or absence of the coupling portion 300 having the above-described composition ratio, the strength of the tube structure 10 according to one embodiment may vary.

Hereinafter, an experiment on the strength of the tube structure 10 that varies depending on the presence or absence of the coupling portion 300 in the tube structure 10 according to an embodiment and the resulting results will be described in detail.

[Experimental Materials]

1. Geotextile

In this experiment, woven geotextile made of polyester was used to investigate the friction characteristics according to the cement-based binder applied to the contact surface of a pair of geotextiles. For the experiment, two types of geotextiles (GT1 and GT2) used as materials for geotextile tubes were selected. The tensile strength of the two types of geotextiles was found to be 205 kN/m and 241 kN/m on average in the warp direction (Machine Direction, MD) and weft direction (Cross Machine Direction, CMD), respectively, depending on the type of geotextile. It shows some difference. The elongation was slightly greater in GT2 than GT1 in the warp direction, and was similar in the weft direction at about 11% for both types of geotextiles. The intersection where the warp and weft intersect is formed less in GT1 than in GT2. Accordingly, the effective hole sizes of GT1 and GT2 were 219μm and 73μm, respectively, and it can be seen that the effective hole size of GT1 is about three times larger than that of GT2.

2. Cement-based binder

The cementitious binder was manufactured by mixing ultra-fast setting cement, fly ash, sand, quick setting agent, and water. First, rapid setting cement was used as a product with an initial setting time of more than 20 minutes and a final setting time of less than 60 minutes. The sand was used after mixing two types of silica sand with average particle diameters of 0.53 mm and 0.17 mm, respectively, at a weight ratio of 2.67 to 1. The density and fineness of fly ash are 2.2 g/cm ³ and 3850 cm ² /g, respectively, and its chemical components include silicon dioxide (SiO2), sulfur trioxide (SO3), and calcium oxide (CaO) at 62.9%, 0.1%, and 2.1%, respectively. It contains %. To accelerate the hardening process, an alkali-free quick-setting agent was used, and tap water at a temperature of 15°C was used to mix the cement-based binder.

The mixing ratios of the materials constituting the cement-based binder are summarized in Table 1. In order to minimize changes in the properties of the cement-based binder due to mixing, the mixing process was carried out in the same order as follows. First, rapid hardening cement, fly ash, and sand were dry mixed, then mixed with water for a certain period of time, and an accelerator was added. To evaluate the fluidity, setting time, and strength characteristics of the mixed cementitious binder, flow tests, setting time tests, and uniaxial compression tests were conducted. The flow test was conducted according to the method presented in ASTM D6103, and the maximum diameter and vertical diameter of the spread sample were measured and the average was measured, and the flow value was found to be 459 mm. To determine the setting time of the sample, a setting time test was performed according to ASTM C191. The initial and end times for an invasion of 25 mm were 142 minutes and 520 minutes, respectively. For the uniaxial compression test, samples with a diameter of 50 mm and a height of 100 mm were wet cured for 24 hours and then underwater cured for 28 days. The uniaxial compression test was performed by applying a load to each sample at a speed of 1 mm/min, based on ASTM D4832. The experimental results showed that the uniaxial compressive strength increased with curing time, and the uniaxial compressive strength of the sample cured underwater for 28 days was 876 kPa.

[Experimental Method]

1. Direct shear tester

To evaluate the friction characteristics of a sample combining cement-based binders between two geotextiles, a direct shear test was performed using a direct shear tester. The upper and lower boxes were made of highly rigid brass and aluminum to minimize deformation due to vertical stress. In order to fix the geotextile during the direct shear test, the top and bottom geotextiles were fixed using clamps on the upper and lower boxes, respectively. In order for the geotextile and the shear box to behave as one unit without being separated, irregularities with a width of 1 mm and a depth of 0.5 mm were designed on the contact surfaces of the upper box and the lower box. By using the shear box manufactured in this way, the shear strength characteristics of the rectangular contact surface between the upper and lower boxes can be evaluated.

2. Test procedure

The following process is required to cure a cementitious binder sample between two geotextiles. First, in order to cure the cement-based binder between two geotextiles cut to a certain size, separate thin rectangular molds were connected using screws. After placing the assembled mold on one geotextile, cement-based binder was cured inside the mold to create samples with the width, length, and height of 100 mm, 70 mm, and 4 mm, respectively. Afterwards, another geotextile was covered over the formed binder to ensure that the cement-based binder was adhered between the two geotextiles. The two geotextiles and the attached cementitious binder were cured in water for a planned period while maintaining a constant temperature. In this study, in order to determine the early strength of cement-based binders considering the construction conditions of multi-stage geotextile tubes, which require securing initial stability, direct shear tests were performed only on samples cured for up to 7 days after mixing.

To perform a direct shear test using a cementitious binder sample cured between two geotextiles, the following sample composition process is followed in a shear box. First, place the cured sample in the center of the lower box, and then fix one end of the lower geotextile to the lower box using a clamp. After placing the upper box on the sample fixed with the lower box in the area where the cement-based binder is composed, the upper geotextile is fixed to the upper box using the clamp of the upper box. At this time, the applied mold is removed to reduce damage to the sample. Through the use of such a mold, it is possible to cure samples of a certain thickness. After sample composition was completed, vertical stresses of 32 kPa, 60 kPa, and 116 kPa were applied to each sample using a direct shear tester. After the vertical displacement converged to a constant value, the shear experiment was started while maintaining the shear rate at 1 mm/min, and the experiment was performed until the horizontal displacement of 20 mm was reached.

[Experiment result]

1. Shear strength of geotextile contact surface

To analyze the shear strength characteristics of the contact surface between geotextiles, a direct shear experiment was performed under three vertical stresses, and the shear stress was measured until the horizontal displacement reached 20 mm. Overall, the shear stress was found to increase as the initial horizontal displacement increased. In the case of GT1, the shear stress reached a peak state as the horizontal displacement increased, then decreased and converged to a constant value at the large strain rate. After the peak state, the decrease in shear stress was greater as the vertical stress increased. On the other hand, in the case of GT2, after the initial shear stress increased, the shear stress was maintained with constant fluctuations as it developed at a large strain rate without a clear peak state. It is believed that the shear stress after the peak state changes depending on the number of intersections on the geotextile surface. In GT2, which had relatively many intersections, periodic changes in shear stress appeared more clearly, and as the vertical stress increased, the fluctuation range of shear stress also increased. Overall, as the vertical stress increased, the horizontal displacement reaching the shear strength increased, and in the case of GT1, the shear strength was reached at a larger horizontal displacement than GT2. The relationship between vertical stress and shear strength appeared in the form of a straight line passing through the origin, and the linear relationship in both types of geotextiles showed a correlation coefficient of more than 0.99. From the slopes of the two straight lines, the friction angles of GT1 and GT2 were confirmed to be 37.8° and 35.1°, respectively.

Figure 3a shows the change in shear strength according to horizontal displacement of the tube structure 10 to which the coupling portion 300 is not applied.

Like the shear strength of the geotextile contact surface described above, the shear strength of the tube structure 10 according to an embodiment to which the coupling portion 300 is not applied is initially increased with an increase in horizontal displacement as shown in Figure 3a, and then , Above a certain horizontal displacement, the shear strength appears to converge to a certain value.

2. Shear strength of the contact surface where cementitious binder is applied

The results of a direct shear test conducted to evaluate the shear strength characteristics of the contact surface where cementitious binder was applied between geotextiles are as follows. Similar to the results of the contact surface without the binder applied, the shear stress reached a peak state as the horizontal displacement increased and then converged to a constant value at the large strain rate. Overall, it can be seen that the shear strength of the contact surface where the cementitious binder was applied between geotextiles was significantly increased compared to the shear strength of the contact surface where the binder was not applied. Additionally, the horizontal displacement reaching the shear strength at each vertical stress generally increased.

The contact surface of GT1 showed a slight increase in shear strength as the curing time increased. However, the change in horizontal displacement of the peak state according to curing time did not show a consistent pattern. After 3 days of curing, the shear behavior at the contact surface of the two types of geotextiles is as follows. The change in shear stress at the contact surface of GT2 where the cement-based binder was applied showed a more distinct brittle fracture pattern compared to the contact surface of GT1. In other words, the shear strength at the contact surface of GT2 was greater than that of GT1, and the horizontal displacement reaching the shear strength was greater at the contact surface of GT1 than that of GT2. Compared to the results of the contact surface where no binder was applied, the increase or decrease in shear stress due to horizontal displacement at the large strain rate of the two types of geotextiles was significantly reduced, which means that by applying the cement-based binder, the shear stress within the geotextile for the change in shear stress at the large strain rate was significantly reduced. It is believed that the impact of the number of intersections has been reduced.

Looking at the results evaluated up to 7 days after curing, regardless of the curing time, the shear strength according to each vertical stress was greater at the contact surface of GT2 than at the contact surface of GT1. Similar to the results of the contact surface where no binder was applied, the change in shear strength according to the vertical stress in the two types of geotextiles showed a linear relationship, and the correlation coefficients were all above 0.96. Meanwhile, in the case of the geotextile contact surface with cement-based binder applied, the y-intercept was derived from the relationship between normal stress and shear strength. When evaluating the strength relationship between normal stress and shear strength using the Mohr-Coulomb fracture envelope, it can be seen that adhesion occurred in most cases of contact surfaces where cementitious binders were applied.

Figure 3b shows the change in shear strength according to horizontal displacement of the tube structure 10 to which the coupling portion 300 is applied on the first day of curing.

Figure 3c shows the change in shear strength according to horizontal displacement of the tube structure 10 to which the joint 300 is applied on the 7th day of curing.

Like the shear strength of the contact surface to which the cement-based binder described above is applied, the shear strength of the tube structure 10 according to an embodiment to which the coupling portion 300 is applied initially increases with the increase in horizontal displacement as shown in Figures 3b and 3c. After increases, the shear strength may converge to a certain value above a certain horizontal displacement. However, compared to the tube structure 10 of FIG. 3A, it can be seen that the overall shear strength of the tube structure 10 of FIGS. 3B and 3C is significantly increased.

Figure 4 shows an embankment method using a tube structure 10 according to one embodiment.

Referring to FIG. 4, the embankment method using the tube structure 10 according to one embodiment may include steps S1 to S6.

In step S1, a plurality of tubular supports 100 may be provided. At this time, the support portion 100 may be provided as a geotextile tube manufactured in a cylindrical shape.

In step S2, the filling portion 200 may be filled into the support portion 100.

In step S3, a first support layer (L1) can be formed by placing a plurality of support parts (100', 100'') on the ground.

In step S4, the coupling portion 300 may be cast in the space formed between the adjacent support portions 100 in the first support layer (L1). At this time, the coupling portion 300 may include a cement-based binder composed of cement, fly ash, sand, silt, quick-setting agent, and water, as described above.

In step S5, the second support layer (L2) can be formed by stacking a plurality of support parts (100''') on the first support layer (L1).

In step S6, the joint portion 300 can be cured.

Accordingly, the first support layer (L1) and the second support layer (L2) of the tube structure 10 according to one embodiment can be stably coupled.

As described above, the tube structure 10 and the embankment method using the same according to an embodiment are made by embanking geotextile tubes in multiple stages and combining these tubes with a cement-based grout material, which is a high fluidity filler, to create an embankment with improved stability and watertightness. can be provided.

In addition, the tube structure 10 according to one embodiment mixes the binder at an optimal composition ratio, so that the joint 300 with high fluidity and appropriate adhesion and strength is poured, and the bond between the tubes is strengthened according to the purpose of the embankment. In addition, if disassembly of the tube is necessary in the future, it can be easily dismantled.

In addition, the tube structure 10 according to one embodiment uses dredged soil as a filler inside the tube, which can improve structural performance due to the cost reduction effect of the drought prevention system and the stability of the geotextile tube when freshening the reservoir.

As described above, the embodiments of the present invention have been described with specific details such as specific components and limited examples and drawings, but this is only provided to facilitate a more general understanding of the present invention, and the present invention is limited to the above embodiments. This does not mean that various modifications and variations can be made from this description by those skilled in the art. For example, the described techniques may be performed in a different order than the described method, and/or components of the described structure, device, etc. may be combined or combined in a different form than the described method, or may be used with other components or equivalents. Appropriate results can be achieved even if replaced or substituted by . Accordingly, the spirit of the present invention should not be limited to the described embodiments, and the scope of the patent claims described below as well as all things that are equivalent or equivalent to the scope of this patent claim shall fall within the scope of the spirit of the present invention. .

10: Tube structure
100: support part
200: Filling part
300: coupling part

Claims (7)

A plurality of supports formed in a tubular shape;
A filling part that fills the inside of the support part; and
A coupling part poured into the space formed between the support parts filled in multiple stages;
Including,
The support or filling portion allows water to enter or exit,
The coupling portion includes a cement-based binder composed of cement, fly ash, sand, silt, quick-setting agent, and water, and couples the plurality of supports to each other,
For 100 parts by weight of the cement-based binder,
15 to 17 parts by weight of the cement;
12 to 13 parts by weight of the fly ash;
30 to 33 parts by weight of the sand;
12 to 13 parts by weight of the silt;
0.5 to 1 part by weight of the quick-setting agent; and
25 to 26 parts by weight of water;
Includes,
A tube structure in which the quick setting agent is composed of an alkali-free agent.

delete According to paragraph 1,
The support part is a geotextile tube manufactured in a cylindrical shape,
A tube structure wherein the filling portion includes dredged soil.
Providing a plurality of tubular supports;
Filling the inside of the support part with a filling part;
forming a first support layer by disposing a plurality of the support parts on the ground;
Casting a joint portion in a space formed between adjacent supports in the first support layer; and
forming a second support layer by stacking a plurality of support parts on the first support layer;
Includes,
The joint includes a cement-based binder composed of cement, fly ash, sand, silt, quick-setting agent, and water,
After forming the second support layer, further comprising curing the binder,
The first support layer and the second support layer are bonded to each other by the binder,
For 100 parts by weight of the cement-based binder,
15 to 17 parts by weight of the cement;
12 to 13 parts by weight of the fly ash;
30 to 33 parts by weight of the sand;
12 to 13 parts by weight of the silt;
0.5 to 1 part by weight of the quick-setting agent; and
25 to 26 parts by weight of water;
Includes,
An embankment method using a tube structure, wherein the quick setting agent is an alkali-free agent.
delete delete According to paragraph 4,
An embankment method using a tube structure, wherein the support portion is a geotextile tube manufactured in a cylindrical shape.

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