KR101340871B1 - Psc girder and psc girder making method using concrete saddle and psc girder thereof - Google Patents

Abstract

The present invention relates to a PSC girder manufacturing method for arranging tendons in a curve shape and using a concrete saddle, which is easily manufactured and secures economic feasibility and structural efficiency, when the PSC girder is manufactured in a pretension method. The concrete saddle is integrated with a lower plate fixed to a bottom plate and the top surface of the bottom surface and is manufactured to include an upper block body where a horizontal passing hole is formed so that the tendons penetrate the hole. The concrete saddle is fixed to the bottom plate.

Description

PSC girder manufacturing method using concrete saddle and PSC girder using concrete saddle {PSC GIRDER AND PSC GIRDER MAKING METHOD USING CONCRETE SADDLE AND PSC GIRDER THEREOF}

The present invention relates to a PSC girder manufacturing method using concrete saddles and a PSC girder using concrete saddles. More specifically, in the production of PSC girder by pretension method, it is possible to arrange the tension member in a bent form, but also to manufacture PSC girders using concrete saddles that can be manufactured easily, economically and secure structural efficiency and PSC using concrete saddles. It's about the girder.

Conventional prestressed concrete girder (PSC girder) generally gives tension to the tension material (typically PS stranded wire) in advance and tensions it, and then casts and hardens the concrete after releasing the tension material. Pre-tension method where tension is introduced,

Sheath is disposed throughout the concrete cross section, and after curing of the concrete cross section, the PS tension material is inserted into the sheath and tensioned, so that it is settled at both ends of the PSC girder, and is divided into a post-tension method for introducing a tension force to the concrete cross section.

In this case, the pretension scheme has the following advantages over the posttension scheme.

First, because the tension is introduced by the adhesion of concrete and PS tension material, no separate anchorage is required.

Second, she doesn't need a sheath because she is nervous in advance.

Third, grouting, which is the filling of sheath, required in the post-tension method, is not necessary.

Fourth, fixing reinforcing bars in the vicinity of the fixing device of the PS tension material required in the post-tension method is not necessary.

Fifth, compared with the post-tension method, the abdominal thickness of the PSC girder and the concrete cross-sectional dimension of the fixing unit can be minimized.

Sixth, members of the same shape and dimensions can be manufactured in large quantities in a long-line manner (producing a plurality of members at once with one tension).

That is, a method using one mold 10 as shown in Figure 1a is called a single mold method, as shown in Figure 1b a plurality of molds (10, Mold) arranged in series on the bed 20 and at the same time a method of introducing a tension force The method of manufacturing a plurality of members by introducing a single tension force is called a long-line method.

At this time, the bed 20 is installed on the floor by the shear key 21, and after the tension member 40 is installed separately, the tension line 60 is used to tension the PS tension member 30 to produce a member. The single mold method, the long line method or the same manufacturing process.

Despite the various advantages of the pretension method, the PSC girder based on the pretension method applied in Korea is insignificant because the following disadvantages of the pretension method exist.

In other words, in general, it is mechanically appropriate to arrange the tension member in a curved shape, whereas the pretension method has a disadvantage in that the efficiency of the tension member is inevitably decreased because the tension member is normally placed in a straight line.

Accordingly, the present invention provides a method for producing a PSC girder using a concrete saddle that can secure the efficiency of the arrangement while ensuring the arrangement of the tension material in the desired bent shape in the production of the PSC beam by the pretension method The task is to solve the provision of PSC girders using concrete saddles.

In order to solve the above problems,

First, in manufacturing the PSC beam by the pretension method, in order to arrange the tension member in a form of bending inside the formwork installed on the workbench, various means may be possible, but the present invention uses the saddle.

Typically, the saddle is a device that is installed to maintain a flexible flexural tension material in a bent form, but it can be seen that the one made of a steel material is installed in a manner embedded in the conventional PSC girder as shown in Figure 1c.

However, when the birds made of steel are used to increase the weight of the PSC girder, and the cost is also expensive to manufacture the steel, there is a problem of corrosion, but in the present invention when placing concrete for PSC girder by making concrete saddle The concrete birds were allowed to be buried.

Second, the concrete saddle is to be fixed to the bottom plate concrete of the production table and to facilitate the manufacture and installation by forming the upper block and the lower plate integrally to prevent the concentrated stress due to tension and tension in the tension.

To this end,

In order to manufacture PSC girders by pretensioning method, a workbench including a bottom plate and a reaction wall is installed.

The tension member is arranged in a bent form via concrete saddles installed on the upper surface of the fabrication table,

After the tension material is tensioned and fixed using the reaction wall, the concrete is poured into the formwork installed on the fabrication table so that the concrete birds are embedded and integrated with the poured concrete.

Cutting the tension material after the poured concrete is cured so that compression prestress is introduced into the PSC girder, wherein the concrete saddle is fixed to the bottom plate; And an upper block body integrated with the upper surface of the lower plate, the upper block body having a horizontal through-hole formed therethrough so as to pass through the tension member, and a method for manufacturing the PSC girder using the concrete saddle.

The present invention can overcome the disadvantages of the production of pre-tensioned PSC girder by using the concrete saddle that can be placed freely bent in the tension material in the production of the PSC girder in the pre-tension method, while the concrete birds are embedded in the PSC girder In order to function as a part, it was possible to solve the hassle of increasing the weight, manufacturing and installation of the PSC girder according to the conventional steel birds.

In addition, by having an arcuate bottom with a central curved portion lower than both ends of the PSC girder, it is possible to lower the mold height, improve aesthetics, and form the abdomen of the PSC girder to reduce the weight of the PSC girder, thereby making it slimmer and self-weighting. It is possible to manufacture this small PSC girder.

1a and 1b is a manufacturing diagram of the PSC girder by the conventional pretension method,
Figure 1c is a view of the installation of a conventional buried saddle,
2a, 2b and 2c is a flow chart of the PSC girder manufacturing method according to the present invention,
3 is an exploded perspective view of the concrete saddle of the present invention,
4A, 4B, 4C and 4D are perspective views and construction views of a PSC girder according to the present invention.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. In order to clearly illustrate the present invention, parts not related to the description are omitted, and similar parts are denoted by like reference characters throughout the specification.

Throughout the specification, when a part is said to "include" a certain component, it means that it can further include other components, except to exclude other components unless otherwise stated.

Figures 2a to 2c shows the manufacturing procedure of the hollow PSC girder according to the present invention.

First, as shown in FIG. 2a, the production stand 200 is installed in the production site, which is intended to manufacture the PSC girder 100 in a pretension manner, and the bottom plate 210 is cast to a certain thickness on the floor of the production site. After that, it is installed in such a way that the reaction force walls 220 in the form of vertical walls face each other from both end faces.

The reaction wall 220 is preferably to be integrally formed when the bottom plate 210 is poured.

At this time, the reaction force support 230 is formed on the upper surface of the bottom plate 210 on both sides of the reaction wall 220, for example, and the bottom surface of the reaction force support 230 and the upper surface of the bottom plate 210 are anchor plates. It is to be fixed using an anchor bolt.

In addition, the reaction force support 230 is provided with a fixing hole 231 and a fixing device 232 of the horizontal hole form so that the tension member 300 is penetrated to be fixed to the back of the reaction force support 230.

The fixing hole 231 is formed so as to penetrate in response to the position of the tension member 300 by forming a plurality of up and down on the reaction force support 230, the fixing device 320 may use a conventional tension fixing device. .

The tension member 300 is then tensioned using a tension jack (not shown) and then fixed to the back of the reaction force support 230 using the fixing device 232.

This tension jack is shown to be installed between the reaction force support and the reaction wall in the case of Figure 2a may be arranged to tension the tension member 300 by installing on both sides of the reaction force support 230.

Of course, the tension member 300 may be tensioned and fixed in the reaction force 220 as shown in FIGS. 1A and 1B, but the present invention looks in particular on the basis of using a reaction force support for securing a work space for cutting the tension material.

Next, the tension member 300 is disposed between both reaction force supports 230. Such tension member 300 may use a PC strand (PS strand).

Tension member 300, which is a PC strand, is elastic and can be used because it can be bent. The lower tension member 310, which is embedded in the lower portion of the PSC girder, and the upper tension member 320, which is extended and disposed in the upper portion of the PSC girder, is disposed. )

Accordingly, both ends of the lower tension member 310 penetrate through the reaction walls 220 so that both ends extend to the reaction force support 230 to be fixed by the fixing device 320. The reaction force wall 220 and the reaction force support 230 It can be seen that it is set at the bottom of the and is arranged to pass through the concrete saddle 400 fixed to the bottom plate (210).

The upper tension member 320 is a tension member disposed to be bent downward between the upper ends of both ends of the PSC girder, it can be seen that it is arranged in the U-shaped (bending type) as a whole via the concrete saddle 400.

That is, in the present invention, it can be seen that the tension member is arranged in an open form using the concrete saddle 400 in the PSC girder based on the pretension method.

 It can be seen that the concrete saddle 400 is shown in FIG. 3.

First, the concrete saddle 400 is formed to be divided into a lower plate 410 and an upper block body 420.

First, the lower plate 410 has a predetermined thickness as a concrete plate, but a plurality of fixing holes 411 in the form of vertical holes are formed so that the concrete saddle 400 may be fixed to the bottom plate 210.

The upper block body 420 is formed integrally with the lower plate 410 and has a horizontal through-hole 421 in the form of a horizontal hole so that the tension member 300 can pass therethrough.

Accordingly, the tension member 300 is allowed to penetrate the horizontal through-hole 421, but the upper tension member 320 and the lower tension member 310 may be penetrated, and the size or number of the concrete may be adjusted.

In this case, the upper block body 420 may be concentrated around the horizontal through-hole 421 when the tension member 300 is tensioned, so that the upper block body 420 has a larger thickness than the lower plate 410 and the upper block body 420. The cross-sectional cross-sectional area (horizontal cross-section) of the lower plate 410 is formed to be larger than the cross-sectional cross-sectional area of the upper block body so that the concentrated stress transmitted to) can be distributed to the lower plate 410.

Furthermore, the fixing rod 412 is inserted into the fixing hole 411 of the lower plate 410 so that the position thereof does not change due to the concentrated stress in the concrete saddle 400, and the upper end of the fixing rod is exposed to the upper surface of the lower plate 410. It is to be fastened to the upper surface of the lower plate 410 by a fixing nut 413.

In addition, the lower end of the fixing rod 412 penetrates the fixing hole 211 of the bottom plate 210 formed corresponding to the fixing hole 411 so as to extend below the bottom surface of the bottom plate 210, and also fixed to the bottom The nut 414 is fastened to the bottom surface of the bottom plate 210.

Accordingly, as shown in FIG. 2A, the ground around the fixing hole 211 of the bottom plate 210 is excavated to form a space for fastening the lower fixing nut 414 to the fixing rod 412, and by the upper fixing nut. The fixing rod fastened to the bottom plate 210 is fastened downward by being fastened by the lower fixing nut so that the concrete saddle 400 is firmly fixed to the bottom plate 210 so as not to move to the collecting stress.

Next, formwork corresponding to the shape of the PSC girder is installed and the PSC giant reinforcing bars (not shown) are placed inside the formwork, and the concrete (C) is poured after tensioning and fixing the tension member 300 as shown in FIG. 2B.

At this time, the bottom plate 210 serves as the bottom formwork of the PSC girder, and the reaction wall 220 serves as the end formwork, so only the side formwork (not shown) needs to be installed and the bottom plate of the PSC girder is formed in an arch shape. (210) A separate bottom formwork may be used on the top surface.

Furthermore, in order to reduce the weight of the PSC girder by installing the inner formwork member 250 occupying the same space as the EPS block inside the formwork and placing concrete, the weight of the concrete can be reduced by the volume occupied by the inner formwork member 250. . In FIG. 2B, it can be seen that a plurality of PSC girders 100 are disposed at the center portion.

At this time, the important point is that the concrete saddle 400 is embedded in the poured concrete to be integrally synthesized.

That is, in the production of the pretension type PSC girder, which was difficult to pre-position the tension member in a bending type, for example, U type, the tension member may be pre-arranged using steel birds, as shown in FIG. There is a problem of corrosion, and there is a disadvantage in that it is disadvantageous to the installation of reinforcing steel bars and sheaths, and, among other things, solves the initial fixed setting problem due to the pre-tensioning force used in the pretension method as in the present invention. Since it is difficult to be described below, there is a limit in applying it to the pretension type PSC girder as it is.

However, the present invention, because the concrete saddle 400 is buried in the pour concrete, if it can be solved otherwise manufacturing problems, PSC girder self-weight factors, durability problems can be fixed in the initial base plate is optimized in the pre-tension method It has a structure.

Accordingly, when all the concrete is cured as shown in FIG. 2C, the compression prestress is introduced into the cured PSC girder 100 by cutting the tension member 300 by the pretension method.

In this case, it can be seen that the compressive prestress is introduced at the portion where the upper and lower GIN materials overlap each other, that is, at the center portion of the PSC girder, as compared with both ends.

Accordingly, the side formwork is dismantled and the manufactured PSC girder is lifted and mounted in another place.

At this time, the worker dismantles the formwork as shown in Figure 3 in advance unscrewing the lower fixing nut fastened to the bottom plate 210 bottom, lifting the completed PSC girder and rotating the fixing rod to remove from the PSC girder and finish the bottom PSC Complete the girder. To this end, the top of the fixing rod is to be installed more caps so as not to contact the cast concrete.

[Finished PSC Girder 100 of the Invention]

4A, 4B, 4C, and 4D show a completed example and a construction example of a PSC girder according to the present invention.

First, according to FIG. 4A, it can be seen that a straight PSC girder having a cross section having an I-shaped cross section in the longitudinal direction, and a plurality of self-weight reduction holes are formed in the central portion.

In addition, according to Figure 4b as a straight PSC girder cross-section formed in the I-shaped cross section in the longitudinal direction it can be seen that the bottom of the patent is formed in an arch shape, it can be seen also that a plurality of self-weight reduction holes are formed in the central portion.

When the cross-sectional height is increased in the central portion by the Figure 4b, it is advantageous to secure the bending rigidity against the bending moment due to the load, and the appearance is enhanced, and the tension member is arranged in the same manner as in Figure 3a.

4C and 4D, the PSC girder of the present invention is mounted between both shifts and connected by a cross beam to confirm a bridge in a slab formed state.

Since it is manufactured by the pretension method, it is possible to manufacture bridges with low profile heights. In addition, the aesthetic width is also very excellent when the width is not large in the horizontal direction so that the bottom is formed in an arcuate shape.

The foregoing description of the present invention is intended for illustration, and it will be understood by those skilled in the art that the present invention may be easily modified in other specific forms without changing the technical spirit or essential features of the present invention. will be. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive. For example, each component described as a single entity may be distributed and implemented, and components described as being distributed may also be implemented in a combined form.

The scope of the present invention is shown by the following claims rather than the above description, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included in the scope of the present invention. do.

100: PSC girder
200: workbench
210: bottom plate
211: fixing hole
220: reaction wall
230: reaction support
240: tense jack
250: internal formwork member
300: tension material
310: upper tension material
320: lower tension member
400: concrete saddle
410: bottom plate
411: fixing hole
412: fixed rod
413: upper fixing nut
414: lower fixing nut
420: upper block
421: horizontal through hole

Claims (6)

In order to manufacture the PSC girder by the pretension method, the production platform 200 including the bottom plate 210 and the reaction wall 220 is installed,
Via the concrete saddle 400 installed on the upper surface of the production table to be arranged in the tension member 300,
After tensioning and fixing the tension member 300 by using a reaction wall, the concrete is poured into the formwork installed in the manufacturing table so that the concrete birds are embedded and embedded with the poured concrete,
And cutting the tension member 300 after the poured concrete is cured so that compression prestress is introduced into the PSC girder,
The concrete saddle 400 is a lower plate 410 is fixed to the bottom plate; And an upper block (420) having a horizontal through hole (421) formed therein so as to be integrated with the upper surface of the lower plate so that the tension member passes therethrough. The method of claim 1,
Fixing holes 211 and 411 communicate with each other in the bottom plate 210 and the lower plate 410 of the concrete saddle.
Inserting the fixing rod 412 into the communicating fixing holes,
The method of manufacturing a PSC girder using a concrete saddle characterized in that the concrete saddle is fixed to the bottom plate by fastening the upper and lower fixing nuts (413,414) to be fixed to the bottom plate and the concrete saddle. The method of claim 1,
The tension member 300 and the lower tension member 310 is disposed in a straight line through the concrete saddle and
PSC girder manufacturing method using a concrete saddle, characterized in that it also comprises an upper tension member 320 is arranged to be bent through the concrete saddle. The method of claim 1,
Inside the formwork PSC girder manufacturing method using a concrete saddle, characterized in that to form a hole formed in the transverse direction in the PSC girder by further installing an internal formwork member 250. 5. The method of claim 4,
PSC girder manufacturing method using a concrete saddle, characterized in that the bottom of the PSC girder is formed to be straight or arched. In order to manufacture the PSC girder by the pretension method, the production platform 200 including the bottom plate 210 and the reaction wall 220 is installed,
The tension member 300 is disposed in a bent form via the concrete saddle 400 installed on the upper surface of the fabrication table.
After tensioning and fixing the tension member 300 by using a reaction wall, the concrete is poured into the formwork installed in the manufacturing table so that the concrete birds are embedded and embedded with the poured concrete,
After the poured concrete is cured, the tension material 300 is cut and manufactured by the PSC girder manufacturing method using the concrete saddle, including the step of introducing the compression prestress into the PSC girder,
The concrete saddle 400 is a lower plate 410 is fixed to the bottom plate; And an upper block body (420) having a horizontal through hole (421) formed therein so as to be integral with the upper surface of the lower plate so that the tension member penetrates the PSC girder.

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