KR101733928B1 - panel type retaining wall with a continuous beam structure - Google Patents

Abstract

The present invention relates to a panel type retaining wall provided on an inclined surface of a slope. Precast concrete panels are placed vertically on an excavated ground, and a reinforced concrete (RC) beam or a PSC beam is used as a filling concrete for a close contact between the panel and the ground in a space between the back of the panel and the slope to improve the effect of ground contact pressure generated when an earth anchor is tense so as to reduce the number of earth anchors. Accordingly, construction cost is reduced and construction period is shortened, and individual dropout of panels which is able to occur in some slope collapse is prevented by a continuous beams in a form of interconnected strips.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a panel type retaining wall having a continuous beam structure,

The present invention relates to a panel retaining wall structure and a construction method for constructing a precast concrete panel by supporting the precast concrete panel on a ground with an earth anchor. More specifically, in constructing a panel retaining wall by using an earth anchor on a slope, The reinforced concrete or non-reinforced concrete for filling is used not only as a filling member but also as a reinforcing member or a steel wire to form a beam structure and to be used as a bending resistance member as well as a basic function as a compression member.

It has been confirmed that a conventional technique for constructing a panel retaining wall by supporting a panel made of precast concrete on an inclined slope by supporting it with an earth anchor is disclosed in Japanese Laid-Open Patent Publication No. 06-017435 (Jan. 25, 1994). For reference, a concrete panel made of a precast concrete member throughout the present specification is abbreviated simply as a "panel ", and a panel retaining wall constructed by supporting such a panel by an earth anchor is abbreviated as a" panel retaining wall ".

Fig. 1 shows a schematic side view of a prior art panel retaining wall 10, in the case of the prior art panel retaining wall 10 shown in Fig. 1, in which the panel 10a is vertically arranged, The filling concrete 20 is filled and cured at a height equal to or higher than the height of the through hole formed in the panel 10a so that the earth anchor 30 can penetrate through the space between the roof 10a and the slope 40b, The earth anchor 30 is fixed to the slope 40b and the outer end of the earth anchor 30 is fixed to the front surface of the panel 10a by passing through the filling concrete 20 in the direction of the slope 40b from the front of the panel 10a The backing gypsum 50 is filled on the top of the filling concrete 20 in a state where the panel 10a is supported by the earth anchor 30 and the earth anchor 30 is tensed if necessary to form the panel supporting portion , And a method of successively forming such a panel supporting portion in a stepwise manner .

However, in the case of the conventional art, the filling concrete 20 filling the concrete with the height equal to or higher than the height of the through hole formed in the panel 10a is installed with the non-concrete concrete, and the earth anchor 30 is placed on the panel 10a And only a simple function as a compression member for transmitting the applied tensional force to the inclined paper 40b. Another example of the prior art is Korean Patent No. 10-0873408 entitled " Retaining Wall Structure Using Semi-Precast Concrete Panel ", which discloses that a heavy concrete panel 10a which is inconvenient to convey is made thin and then lightly transported, The concrete for filling 20 is added, and the concrete is cast and integrated to form a retaining wall of a required standard.

Specifically, the panel 10a manufactured by the half concrete method is transported to the site to be used for the front formwork. The reinforced bars disposed at the rear are not used for the calculated calculated amount of the reinforcing bars, To the filling concrete 20, or to support the slope 40b. The panel 10a and the panel 10a are not continuously connected to each other in a structure in which the horizontal reinforcing bars are short-circuited according to the standard of the panel 10a, and the shape of the beam is not provided in the longitudinal direction. Therefore, it does not function as a flexural member structurally corresponding to the earth pressure, and the object of the patent claim is also different from the present invention.

Registration No. 10-1419863 entitled " PC panel that does not require dies to be applied to replacement of slab-reinforced retaining walls for slope reinforcement " is a similar mold application technique.

In the conventional panel retaining wall, the unfilled concrete for piling between the back surface of the panel and the inclined surface is simply used as a compression member. Therefore, the amount of the rebar is calculated and arranged so that it can correspond to the earth pressure increasing according to the number of the earth anchors to be formed by forming a beam structure by inserting a small amount of reinforcing bars into the filling concrete, It is also used as a bending resistance member.

Also, in the prior art, the panels are separated from each other in such a manner that the panels are assembled one by one in the longitudinal direction and then filled with concrete on the back surface. Therefore, when the slope collapse partially due to groundwater leaching and soil weathering, the panel is easily separated and collapsed. Small-scale collapse causes massive collapse. Therefore, in order to prevent these individual dropouts, they must be coupled to each other with a rigid structure that can withstand partial collapse earth pressure.

In order to achieve the above-mentioned object, according to the present invention, a pre-fabricated panel is installed on a slope and a reinforced bar or a steel wire is disposed in the filling concrete to fill the in- Make a concrete beam (RC Beam) or a PSC beam (PSC beam).

As described above, according to the present invention, a small amount of reinforcing bars are added to the filling concrete to be poured in order to perform the function of the beam. The earth anchor of the conventional panel type retaining wall has one earth anchor for each panel. However, the present invention can reduce the number of earth anchors by allowing the beam to take charge. Therefore, it is possible not only to reduce the cost of drilling the earth anchor but also to reduce the cost of material such as soil nailing, steel wire, and mortar to be inserted into the inside, and shorten the construction time. In addition, the conventional panel type retaining walls are separated from each other, and the panel is easily separated from the slope collapse. The present invention is mutually bonded with a rigid reinforcing bar to prevent such partial collapse.

1 is a schematic side view of a panel retaining wall 10 according to the prior art.
2 (a) is a side view of a reinforced concrete beam 60a formed on a rear surface of a panel 10a according to an embodiment of the present invention.
2B is a side view of the PSC beam 60b formed on the back surface of the panel 10a according to another embodiment of the present invention.
Fig. 3-a is a side view of the reinforced concrete beam 60a of the present invention, Fig. 3-b is a front view, and Fig.
Fig. 4A is a side view of the PSC beam 60b of the present invention, Fig. 4B is a front view, and Fig. 4C is a plan view.
5-a is a schematic plan view showing a prior art panel retaining wall 10;
5B is a schematic plan view showing the PSC beam 60b of the present invention.
FIG. 6-a is a side view showing an earth anchor 30 construction in a slope 40b of the prior art.
Fig. 6-b is a side view showing an earth anchor 30 in a slope 40b of the present invention. Fig.
7 (a) is a perspective view of the reinforcing bars of the panel 10a of the prior art.
Fig. 7-b is a perspective view showing the reinforcing bars disposed behind the panel 10a in Fig. 7-a.
7 (c) is a perspective view of the reinforcing concrete beam 60a of the present invention
Fig. 7-d is a layout diagram of the rear reinforcing bars of the panel 10a in Fig. 7-c.
8 is a graphical perspective view showing the construction of the reinforced concrete beam 60a of the present invention.
9 is a graphical perspective view showing the PSC beam 60b of the present invention.

1 is a schematic side view of a panel retaining wall 10 according to the prior art. The filling concrete 20 laid between the back surface of the panel 10a and the slope 40b as described above is simply pressed by the compression member for transmitting the tensional force of the earth anchor 30 applied to the panel 10a to the inclined surface, As you use it, you are putting no-load concrete without rebar. Plain concrete is effective for compression but is vulnerable to tensile stresses and cracks. Therefore, reinforcing bars are placed in concrete areas where tensile stresses are generated to cope with tensile stresses. Placing reinforcing bars at the location where tensile stresses occur and placing a small amount of auxiliary reinforcing bars at locations where compressive stresses occur will make the horizontal members long and the concrete will be transformed into a reinforced concrete beam. That is, a member resistant to bending stress. Conventional technology uses expensive concrete only as a compression member, which is uneconomical in terms of material utilization. In the present invention, a small amount of reinforcing bars are disposed to form a beam structure, which is a member for bending resistance, to enhance utility value.

In the conventional earth anchor method, the earth anchor 30 is composed of a fixing device, an in-ground connecting member, and a grout. The connecting member uses a soilless nail ring 80a as a bolt-type reinforcing bar or a steel wire 80b . Soil nailing is used as an example here. The reinforced concrete beam 60a and the PSC beam 60b of the present invention will be collectively referred to as beam 60. [

2 is a schematic side view of a panel retaining wall 10 according to an embodiment of the present invention.

2 (a) shows a reinforced concrete beam 60a, which is a reinforced concrete beam, formed on the back surface of the panel 10a. A frame-shaped structural reinforcing bar was disposed at the position of the filling concrete 20 of the conventional panel retaining wall 10. Here, the X axis is the direction of the slope 40b in front of the panel 10a, the Y axis indicates the direction from the bottom to the top of the panel 10a, and the Z axis indicates the direction in which the panel 10a is arranged in the longitudinal direction. Although the cross-section of the filling concrete 20 can be inverted triangular as in the conventional technique, it is preferable to form a rectangular cross-section as much as possible, as shown in 2-a. The reinforced concrete beam 60a refers to a rectangular horizontal member in which reinforced concrete reinforced concrete has a rectangular cross section and is elongated in the Z-axis direction. In the arrangement of the reinforcing bars, the main reinforcing bars 90a are arranged in front of the reinforcing concrete beams 60a, and the auxiliary reinforcing bars 90b are arranged in the rear. The reinforcing concrete beam 60a is bent in the negative X direction as seen in plan view by the earth pressure 40c of the slope 40b such that the tensile stress is applied in the forward direction This is because a compressive stress is generated in the resin.

Here, the steel bars refer to reinforcing bars that are placed in positions subjected to structural tensile stress, and the reinforcing bars are reinforcing bars used to supplement load distribution or cracks. Therefore, the cast iron can receive more strength by using thicker reinforcing steel than the auxiliary steel. However, it is apparently the same shape of rebar. Also, a stirrup reinforcing bar 90c which surrounds the main reinforcement 90a and the auxiliary reinforcement 90b so as not to escape outward is disposed. Thus, the reinforced concrete beam 60a is simply formed on the back surface of the panel 10a. FIG. 2-b shows another embodiment of the present invention in which a steel wire 80b is disposed in place of the main steel rope 90a to stretch the concrete after curing to form a more efficient PSC beam (Prestressed Concrete Beam). The PC steel beam is a material with higher tensile strength than the rebar, and the PSC beam is a universal beam used in many bridge structures. Detailed description such as the arrangement of the steel wire will be omitted.

FIG. 3-a is a side view of the reinforced concrete beam 60a shown in FIG. 2-a, FIG. 3-b is a front view, and FIG. In Fig. 3-a, a cast iron rope 90a is arranged forward, a secondary reinforcing bar 90b and a stirrup reinforcing bar 90c are arranged. The arrangement of the reinforcing bars is not limited to the embodiment, and in actual application, the earth pressure 40c applied to the beam 60 is calculated and arranged. In addition, the reinforcing bars are assembled in advance in the factory by assembling the reinforcing bars into a reinforcing net, so that the reinforcing bars can be installed only in the field to facilitate the convenience.

4A is a side view of the PSC beam 60b shown in FIG. 2B, FIG. 4B is a front view, and FIG. 4C is a plan view. A steel wire 80b was disposed in front of the cast iron rope 90a, a secondary reinforcing bar 90b and a stirrup reinforcing bar 90c were disposed at the rear.

FIG. 5-a is a plan view of a prior art panel retaining wall 10 with only a brief outline, and FIG. 5-b is a simplified plan view of the PSC beam 60b. In the prior art, each earth anchorer 30 is provided for each panel 10a to correspond to the earth pressure 40c. However, as shown in the PSC beam 60b, some of the earth anchors 30 can be omitted. However, the earth pressure 40c, which is omitted by the earth anchor 30, is transmitted to the PSC beam 60b, and the earth pressure 40c is transmitted to P1 and P2 earth anchors 30 on both sides. Therefore, the P1 and P2 earth anchors 30 need to support the earth pressure 40c of the omitted earth anchor more easily if they are slightly further pierced at the piercing depth of the conventional earth anchor 30.

In FIG. 6-a, the earth anchor 30, which is installed on the slope 40b in a region where the A zone is a collapsing risk ground zone and the B zone is a solid ground zone, passes through the A zone and the arc breaking line, Settlement. The length of the soilless nail 80a installed in the A zone is referred to as a free zone and the zone B is referred to as a fixing zone. The soilless nailing 80a is basically to pass through the A zone. In other words, the free space is a part that does not help the earth anchor (30) support. The soil nail ring 80a installed in the fixing zone is attached to the ground 40a with cement and a bearing force is generated by frictional force. The conventional earth anchor 30 is constructed such that as shown in the illustration of FIG. 5-a, the soil nailing 80a of the four earth anchors 30 from the G1 to the G4 times the free ground is basically excavated, It has a bearing capacity by having a design fixation length in the intestinal tract. However, when the PSC beam 60b is installed or the reinforced concrete beam 60a is installed as shown in FIG. 5-b, P1 and P2 earth anchors 30 are installed and two earth anchors can be omitted. Therefore drilling work is greatly reduced. The number of omitted earth anchors 30 is an example given as an example, and more earth anchors may be omitted if necessary. However, the beam 60 and the remaining P1 and P2 earth anchors 30 must be large.

Of course, in the above example, as the two earth anchors 30 are reduced, the earth pressure 40c to be supported by the remaining two earth anchors 30 is increased. However, this is because the soil nails 80a of the two earth anchors P1 and P2 ) Has reached the settlement area after passing through the free zone, it is possible to easily secure the additional settlement length as much as necessary by further excavating the perforations. Also, due to the characteristics of the ground, the settlement effect becomes better as the ground becomes deeper as it gets deeper into the ground. Which is one of the important matters of the present invention. According to the present invention, the soil nailing 80a can be saved by a length corresponding to a substantially free length. Needless to say, the soil nailing 80a of the present invention should use a slightly upward standard to meet the increased earth pressure, but the amount of savings due to the free field application is large.

In other words, drilling cost, soilless nailing, cement materials, etc. can be greatly reduced, and the construction period can be shortened.

In addition, in FIG. 5-a, the conventional panel retaining wall 10 has the panels 10a separated from each other. When the panel 10a is installed in the field, a simple connecting port is fastened or welded between the panel 10a so as not to generate a transformer elevation. However, this is a simple type of fastening for collapsing the panel 10a, It can not withstand the earth pressure. However, as shown in FIG. 5-b, the PSC beam 60b or the reinforced concrete beam 60a of the present invention connects the panel 10a like a single band, thereby preventing dropout even if partial slope collapse occurs. This is an important function in the slope retaining wall of the slope 40b. When the earth pressure is increased due to scouring or hydraulic pressure increase due to ground water, rainy season, etc., local destruction due to dropout occurs in the conventional technique. As time passes, Destruction. In the present invention, a plurality of ground anchors 30 connected to each other are integrally formed to correspond to the earth pressure, thereby preventing individual dropouts and preventing breakage.

Therefore, the present invention has an important function of preventing local slope failure as well as drastically reducing the construction cost with a small amount of reinforcing bars.

Fig. 7 is a schematic view of the reinforcing bars. Only the main reinforcing bars will be briefly described. 7A is a perspective view showing a conventional reinforcing bar arrangement and is a sectional view of the inner cross section of the panel 10a so as to prevent damage to the panel 10a by the earth pressure generated by compaction of the back gravel 50 and earth pressure generated when the earth anchor 30 is pulled. The cast iron 90a is disposed at the rear side of the cast iron 90a. This is to prevent the panel 10a from bowing like a bow when viewed from the side and cracking or tensile breakage of the upper end of the panel 10a. Further, the auxiliary reinforcing bars 90b are arranged at right angles to the rear casting steel bars 90a so as to distribute the load evenly. The front portion of the panel 10a receives the compressive force, and since the concrete corresponds to the compressive stress, the reinforcing bars are unnecessary, but a small amount of the auxiliary reinforcing bars 90b are disposed for the purpose of preventing cracks or the like. 7B is a rear view of the reinforcing bars disposed behind the panel 10a of FIG. 7A of the prior art. The reinforcing bars 90a and the reinforcing bars 90b cross each other. Fig. 7-d is a rear reinforcing bar layout view of the panel 10a of Fig. 7-c. 7C is a perspective view of the reinforcing bars of the reinforced concrete beam 60a according to the present invention. The reinforcing bars installed on the panel 10a are almost similar to those of the conventional panel 10a. The reinforcing bars arranged horizontally in the front reinforced bars were upgraded from the reinforcing bars 90b to the reinforcing bars 90a. The auxiliary reinforcing bars 90b horizontally disposed at the rear lower end are moved to the position of the beam 60 to be replaced with the cast iron bars 90a. This is because it is not necessary to place them at the same position. In the present invention, the main duct 90a in front of the panel 10a is not installed at the time of manufacturing the panel 10a but only the side through hole 70 at the time of manufacturing, and after the panel 10a is installed in the field, It is another feature of the present invention that the cast iron rope 90a or the steel wire 80b is inserted into the through hole 70 and disposed. In other words, when viewed from a structural point of view, it is used as a tensile bar.

In addition, the beam 60 is formed by arranging the structural reinforcing bars in a rectangular shape in the position of the filling concrete 20 in FIG. 7-a in FIG. 7-c. First, there is a reinforced concrete beam 60a formed on a lateral side of the XY section, and the reinforcing concrete beam 60a itself has vertical reinforcing bars 90a at the front and rear reinforcing bars 90b at regular intervals, And a framed stirrup reinforcing bar 90c surrounding it is arranged. The reinforcing frame of a rectangular shape is continuously arranged in a section where the panel 10a is installed in the Z direction which is the longitudinal direction. The method of assembling the reinforcing bars for forming the beams 60 is a common practice, and a more specific method of laying the reinforcing bars will be omitted. When the reinforcing bars are compared with each other, the reinforcing bars of the panel 10a are almost the same, but some of them are deleted. And a portion of the beam 60 is additionally provided with a cast iron 90a, an auxiliary reinforcing bar 90b and a stirrup reinforcing bar 90c in the filling concrete 20.

That is, the present invention is an economical technology that can easily form the beam 60 and obtain many advantages without adding so much reinforcing bars to the prior art panel retaining wall 10. For reference, the cast iron rope 90a is displayed in black, and the auxiliary reinforcing bars 90b and 90b are indicated by lines of empty spaces. Other detailed reinforcing bars giving confusion in the description are not shown. Also in the present invention, a small amount of shear reinforcement is installed on the back surface of the panel 10a for the connection between the panel 10a and the concrete 20 for filling, as in the prior art. This has already been commercialized in the panel retaining wall 10. A reinforcing bar for a lifting ring (not shown) is installed on the back surface of the panel 10a in order to manufacture and transport the panel 10a. The reinforcing bars for lifting rings attached to the back surface of the panel 10a are naturally made of a filler concrete ), And perform the shear reinforcing function, which is a function of mutual bonding. Therefore, the method of integrating the panel 10a and the filling concrete 20 is not commonly known as a technique.

8 is a graphical perspective view illustrating the reinforced concrete beam 60a according to the present invention. Side through holes 70 are formed in the front portion of the panel 10a in the Z direction as shown in Fig. As shown in FIG. 7-b, in the conventional panel 10a, the auxiliary reinforcing bars 90b horizontally arranged are disposed only inside the panel 10a. That is, not connected between the panels 10a, but separated. That is, the panel 10a is an independent structure. However, the panels 10a of the present invention are characterized in that they are interconnected to integrate and make another type of beam 60 structure using the continuous panel 10a. In order to form this, the cast iron rods 90a are continuously connected to the side through holes 70 formed in front of the panel 10a, and grout is performed. The steel wire 80b may be inserted instead of the cast iron 90a. The reinforcing bar to be inserted is calculated by using the reinforcing bar of the design standard. The earth pressure 40c is transmitted to the panel 10a integrated with the beam 60 at the same time when the earth pressure 40c acts. However, in the conventional case, the panels 10a are separated individually. In other words, conventionally, the separated panel 10a has a structure in which the earth pressure 40c is separately provided through each of the earth anchors 30. That is, the conventional panel 10a is not a beam structure.

In the present invention, the filling concrete 20 is changed into a beam 60 structure, and further, the panel 10a installed in the former is also connected to a beam 60 structure. The portion where the filler concrete 20 is changed to the beam structure is referred to as " filler portion continuous beam 100a ", the portion where the panels 10a are connected to each other and the beam structure is changed to " Continuous beam 100b ". As shown in FIGS. 7A and 7C, it is possible to make the reinforcing bars disposed at the same position in front of the panel 10a by using a slightly thicker reinforcing bar, will be. You must place reinforcing bars connected to each other. In this case, the filling concrete 20 was changed to the beam 60 structure, and the separated panel 10a was connected to the beam 60 structure.

FIG. 9 is a graphical perspective view illustrating the PSC beam 60b of the present invention, showing the rebar assembly, the steel wire 80b, and the like. A steel wire 80b is used in place of the main steel wire 90a and a beam 60 is made by using the auxiliary steel wire 90b.

The present invention is constructed in the following order.

Step 1: installing the precast concrete panel 10a on the slope 40b,

Step 2: Insert the main iron wire 90a or the steel wire 80b into the side through hole 70 formed in the side surface of the panel 10a and grout to connect the panel 10a and the panels to integrate the panel side continuous beam 100b A step of installing a structural reinforcing net or a steel wire 80b and a reinforcing bar pre-assembled between the rear of the panel 10a and the slope 40b; Forming concrete continuous beam 100a in the longitudinal direction, that is, assembling direction of the panel 10a; Step 5: installing the reinforcing bars 80a and 80b in the third step, , The step of stretching the steel wire

Step 6: After inserting the earth anchor 30, it is pulled and fixed with cement grout,

Step 7: backfilling the rear surface of the panel 10a with the rear soil gypsum 50,

As described above, the present invention uses only a small amount of reinforcing bars in the conventional panel retaining wall 10 to reduce the construction cost, shorten the construction period and increase the safety.

Panel Retaining Wall (10) Panel (10a)
Concrete Filling (20)
Earth anchor (30)
The ground 40a, the slope 40b, the earth pressure 40c,
The back gypsum (50)
Beam 60 reinforced concrete beam 60a PSC beam 60b,
The side through hole (70)
The soil nailing (80a) steel wire (80b)
Steel bars (90a) Steel bars (90b) Steel bars (90c)
Continuous portion 100a of the filler portion, continuous portion 100b of the panel portion,

Claims (3)

A panel 10a continuously installed in the lateral direction; A filler continuous beam 100a which is installed in a transversely continuous manner on the rear side of consecutively installed panels; And an earth anchor (30) formed on an inclined surface through the continuous beam of the panel and the filling part,
A continuous reinforcing bar 90b arranged at upper and lower intervals in the rear, a stirrup reinforcing bar 90c arranged to surround the reinforcing bars and the reinforcing bars 90c, 20, and the reinforcing bars are composed of a reinforced concrete beam 60a arranged continuously on a plurality of panels,
Wherein the earth anchor is installed on at least one skipped panel of the neighboring panel to reduce the installation position of the earth anchor. The method according to claim 1,
A continuous reinforcing bar 90b arranged at upper and lower intervals in front and rear of the filling part continuously, a stirrup reinforcing bar 90c disposed to surround the reinforcing bar, a filling concrete 20 and an inner space formed between the reinforcing bar and the stirrup reinforcing bar Wherein the reinforcing bars and the reinforcing bars are continuously arranged on the plurality of panels and the reinforcing bars and the reinforcing bars are PSC beams for stretching the steel wires after the concrete curing. Retaining wall. delete

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