JP2011252304A - JOINT STRUCTURE AND JOINT METHOD OF PCa COLUMN AND COMPOSITE BEAM - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an effective and appropriate joint structure and joint method for joining a composite beam for which a PCa member is integrally formed at the end of a steel frame beam to a PCa column.SOLUTION: The end of the PCa member 3 in the composite beam 1 is formed as a column beam joint part (panel zone), the PCa column 5 is turned to a height to a beam lower part, the column beam joint part of the composite beam is mounted on the column head of the PCa column, and the PCa column and the composite beam are joined through joint bars 6 arranged between them. The joint bars are arranged beforehand in the state of passing through vertically to the composite beam, and sleeve joints 7 to which the ends of the joint bars are to be inserted are embedded to the PCa column. Or the composite beam is provided beforehand with through-holes for arranging the joint bars later. Or, the joint bars are arranged in the PCa column and the composite beam is provided beforehand with the through-holes for arranging the joint bars. Introduction of prestress beforehand to the PCa member at the end of the composite beam can be considered as well.

Description

  The present invention relates to a structure and method for joining a composite beam having a composite structure of a steel beam and a PCa member to a PCa column.

This type of composite beam is lightweight and excellent in deformability even with a long span, and is advantageous in terms of cost when used in combination with a reinforced concrete column (RC column). Is expected.
As this type of composite beam, as shown in Patent Document 1, for example, a central steel frame part and an end reinforced concrete part are used, and the steel of the central steel frame part is embedded in a part of the end reinforced concrete part to integrate them. In addition, as shown in Japanese Patent Application Laid-Open No. H11-260260, there is known a steel reinforced concrete structure in which an intermediate portion is a steel beam made of H-shaped steel and both ends are covered with half precast concrete.

  In addition, this type of composite beam is constructed between PCa columns by joining the PCa member at the end to the precast concrete column (PCa column). As a construction method, there are many proposals as shown in Patent Documents 3 to 5, for example.

Japanese Examined Patent Publication No. 4-38854 JP 2006-144535 A JP-A-8-4110 JP 2001-193150 A JP 2006-265933 A

However, in any case, it is not always easy to connect the PCa members structurally stably and reasonably in terms of construction, and no perfect structure or construction method has been established.
In particular, it is conceivable to introduce prestress to the PCa member at the end of the composite beam as described above, but in that case, the structure of the joint becomes more complicated, and the tension work of the PC steel material Since the fixing work is also necessary, the joining work is further complicated.

  In view of the above circumstances, the present invention targets a composite beam in which a PCa member is integrally formed at an end portion of a steel beam as a main object, and an effective and appropriate joint structure and joint for joining it to a PCa column. It aims to provide a method.

  The invention according to claim 1 is directed to a composite beam in which PCa members made of precast reinforced concrete are integrally formed on both ends of a steel beam as a main object, and the composite beam is installed between PCa columns made of precast reinforced concrete. In this case, the end portion of the PCa member is joined to the PCa column, and the end portion of the PCa member in the composite beam is formed as a column beam joint portion. Is formed as a height up to the bottom of the beam, and the PCa column is connected to the column head of the PCa column through a joint bar placed between the column beam joints of the composite beam and placed between them. The composite beam is joined.

  The invention according to claim 2 is the joint structure of the PCa column and the composite beam according to claim 1, wherein the PCa member in the composite beam is embedded in a PC steel material and fixed by tension. The PCa member is pre-stressed in the material axis direction in advance.

Invention of Claim 3 is the joining method for joining a PCa pillar and a composite beam by the structure of Claim 1 or 2, Comprising: It has the following (a)-(d) processes, To do.
(a) The composite beam is pre-arranged in a state where the joint bar penetrates the column beam joint part in the vertical direction, and the PCa column has the joint bar on the column head and the column base, respectively. A step of burying a sleeve joint into which an end is inserted,
(b) placing the column beam joint on the column head of the PCa column, and inserting the lower end of the joint bar into the sleeve joint of the column head of the PCa column,
(c) a step of building an upper-floor PCa column on the beam-column joint, and inserting an upper end portion of the joint bar into a sleeve joint of a column base of the PCa column,
(d) A step of filling the sleeve joint with grout and joining the beam-column joint portion of the composite beam and the PCa column via the joint bar.

Invention of Claim 4 is the joining method for joining a PCa pillar and a composite beam by the structure of Claim 1 or 2, Comprising: It has the following (a)-(d) processes, To do.
(a) The composite beam is formed with a through-hole for arranging the joint bar in a state where the joint bar is vertically penetrated in the column beam joint, and the PCa column has a column head and a column base. A step of embedding sleeve joints into which the end portions of the joining bars are inserted, respectively,
(b) After placing the column beam joint on the column head of the PCa column, placing the joint bar in the through hole and inserting the lower end thereof into the sleeve joint of the column head of the PCa column ,
(c) a step of building an upper-floor PCa column on the beam-column joint, and inserting an upper end portion of the joint bar into a sleeve joint of a column base of the PCa column,
(d) A step of filling the sleeve joint with grout and joining the beam-column joint portion of the composite beam and the PCa column via the joint bar.

Invention of Claim 5 is a joining method for joining a PCa pillar and a composite beam by the structure of Claim 1 or 2, Comprising: It has the following (a)-(d) processes, To do.
(a) The composite beam is formed with a through-hole for arranging the joint bar in a state where the joint bar is vertically penetrated in the column beam joint, and the PCa column has the joint at the column head. The bar is provided so as to protrude upward so as to reach the column base of the PCa column disposed on the upper floor, and a sleeve joint into which the upper end of the joint bar is inserted is embedded in the column base. The placing process,
(b) placing the beam-column joint on the column head of the PCa column, and at that time, allowing the joint bar to penetrate the through hole;
(c) a step of building an upper-floor PCa column on the beam-column joint, and inserting an upper end portion of the joint bar into a sleeve joint of a column base of the PCa column,
(d) A step of filling the sleeve joint with grout and joining the beam-column joint portion of the composite beam and the PCa column via the joint bar.

  The invention according to claim 6 is a method for joining the PCa column and the composite beam according to claim 3, 4 or 5, wherein the column of the PCa column is joined to the column beam joint in the composite beam and the top and bottom thereof. By filling the gap between the leg portion and the column head with grout, the sleeve joint leading to the gap through the gap is filled with grout.

  The invention according to claim 7 is the method for joining the PCa column and the composite beam according to claim 4 or 5, wherein the column beam joint in the composite beam and the column base part of the PCa column joined to the top and bottom thereof. And by filling the gap between the column head with the grout, the grout is filled into the sleeve joint that leads to the gap through the gap, and the through-hole that leads from the gap to the upper part thereof It is characterized by filling with grout.

According to the joining structure and joining method of the present invention, the composite beam and the PCa column can be securely and firmly joined to each other via the joining bar, and the end portion of the composite beam functions as a column beam joint (panel zone) as it is. Therefore, it is structurally simple, clear, and rational, and can be constructed efficiently because it can achieve a high degree of PCa for both beams and columns. However, it is possible to greatly improve the construction efficiency compared to the conventional method.
In particular, when prestress is introduced into the PCa member at the end of the composite beam, the PC steel member is embedded in the PCa member at the stage of manufacturing the composite beam, and is tensioned and fixed in advance by a pretension method. Therefore, it is possible not only to introduce prestress into the PCa member without hindrance, but also to significantly reduce the work on site compared to the conventional method where prestress is usually introduced on site at the post-tension method. The workability can be greatly improved.

It is an elevational sectional view showing an embodiment of a junction structure of the present invention. It is sectional drawing (II-II line view in FIG. 1) of a composite beam equally. FIG. 3 is a plan sectional view (a view taken along line III-III in FIG. 1). It is sectional drawing (IV-IV line view in FIG. 1) of the large beam of the beam direction orthogonal to a composite beam equally. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a first embodiment of a joining method according to the present invention and is an exploded view showing an assembly state of a composite beam and a PCa column. It is a figure which shows an assembly condition similarly. It is a figure which shows the condition which built the PCa pillar of the upper floor after joining. It is a figure which shows the condition which built the PCa pillar of the upper floor before joining similarly. The 2nd Embodiment of the joining method of the present invention is shown, and is a figure showing the assembly situation of a composite beam, a PCa pillar, and a joining bar. It is a figure which shows the condition which built the PCa pillar of the upper floor simultaneously. The 3rd Embodiment of the joining method of the present invention is shown, and it is an exploded view showing the assembly situation of a composite beam and a PCa pillar. It is a figure which shows an assembly condition similarly. It is a figure which shows the condition which built the PCa pillar of the upper floor after joining. It is a figure which shows the condition which built the PCa pillar of the upper floor before joining similarly.

1 to 4 show an embodiment of the joint structure of the present invention.
In the figure, reference numeral 1 denotes a composite beam, which has a steel beam 2 made of H-shaped steel as a main body and its both ends (only one end is shown in the figure, but the other end has the same configuration). PCa member 3 made of precast reinforced concrete is integrally formed.
In addition to the beam bars (main bars and stirrups) embedded in the PCa member 3, the PC steel material 4 disposed along the material axis direction is tensioned and fixed. Stress has been introduced.

This composite beam 1 is constructed between PCa columns 5 made of precast reinforced concrete. In the present embodiment, the PCa pillar 5 arranged on each floor is set to a height up to the bottom of the beam, the end of the composite beam 1 is joined to the upper part thereof, and the upper PCa pillar 5 is joined to the upper part thereof. The whole is joined through the joint muscle 6.
That is, in the joint structure of the present embodiment, by joining the composite beam 1 and the upper and lower PCa columns 5 in such a form, finally, the upper and lower PCa columns 5 sandwich the end portion of the composite beam 1. A series of columns are formed, and therefore, the end portion of the composite beam 1 (the end portion of the PCa member 3 that overlaps the horizontal section of the PCa column 5) is integrated with the upper and lower PCa columns 5 as it is. As the column main reinforcement in the column beam connection portion, the above-mentioned joint reinforcement 6 is joined to the column principal reinforcement 5a in the upper and lower PCa columns 5 via the sleeve joint 7. Also works.
In the case of the illustrated example, as shown in FIG. 1, a slight step 3 a is formed on the lower surface of the PCa member 3, and the end of the PCa member 3 (joined to the PCa column 5 and the column beam joint portion). The beam forming dimension of the portion functioning as a) is slightly larger than the other portions, but the step portion 3a may be omitted and the beam forming of the entire PCa member 3 may be made uniform.

In the present embodiment, the series of columns by the PCa columns 5 are outer columns located on the outer periphery of the building, and the composite beam 1 is installed as a large beam in the span direction, as shown in FIG. As shown in the figure, large beams 8 are installed on both sides of the PCa pillar 5 in the column direction. In the case of the illustrated example, the large beams 8 and the outer wall (not shown) are installed at positions shifted to the inside of the building, so that the columnar shape is a so-called out-frame appearance with the outside of the building rather than the outer wall. ing.
The above-mentioned large beam 8 in the row direction is joined to the end portion of the PCa member 3 of the composite beam 1 (that is, a portion functioning as a column beam joint portion). As shown in FIG. 4, these large beams 8 have a structure in which a reinforced concrete beam is formed inside an L-shaped driving form 8a made of PCa, and the large beams 8 facing each other across the column beam joint portion. Are joined to the beam-to-column joint through joints 9 penetrating the beam-to-column joint, and these joints 9 are joined to the beam main bar 8b through the sleeve joint 10. It also functions as the main beam of the beam-column joint.

1st Embodiment of the joining method for joining the composite beam 1 and the PCa pillar 5 with the said structure is typically shown in FIGS.
In the first embodiment, as shown in FIG. 5, in order to join the PCa column 5 to the end portion of the PCa member 3 of the composite beam 1 (that is, the portion that finally functions as the column beam joint as described above). The reinforcing bars 6 are arranged in a state where they are vertically penetrated, and the reinforcing bars 9 for joining the beam 8 in the direction of the beam are protruded on both sides.
The PCa column 5 is set to a height below the beam, and a sleeve joint 7 (see FIG. 6B) for joining the column main bar 5a by inserting the end of the connecting bar 6 into the column head. ) And a sleeve joint 7 (see the column base portion of the PCa column 5 on the upper floor shown in FIGS. 7 and 8) in the same manner.

Then, as shown in FIG. 6, the end of the PCa member 3 of the composite beam 1 is placed on the PCa column 5 with the lower end of the joint 6 inserted into the sleeve joint 7 of the column head of the PCa column 5. At that time, the composite beam 1 is temporarily supported with a slight gap between them, and a grout filling mold 11 is attached around the gap, and an injection port 11a and a mold 11 are attached to the mold 11. A discharge port 11b (see FIG. 5) is formed.
In addition, on both sides of the end portion (column beam joint portion) of the PCa member 3 of the composite beam 1, a driving form 8 a for constructing the large beam 8 in the beam direction is attached.

  After that, the grout 12 such as high-strength concrete is pressurized and filled into the mold 11 from the injection hole 11a of the mold 11 to fill the gap, and the sleeve joint 7 leading to it is also filled. At this time, it is possible to reliably fill the entire gap and the entire sleeve joint by pressurizing and filling until the grout 12 flows out of the discharge port 11b. Thus, the composite beam 1 and the PCa beam 5 are securely and securely joined.

Before and after the above process, after placing the bars in the placement form 8a, placing concrete and constructing the girder 8 in the direction of the girder, the process proceeds to construction on the upper floor as shown in FIG. .
That is, the upper PCa column 5 is built on the upper part of the end portion (column beam joint portion) of the composite beam 1, and the upper end portion of the joint bar 6 is inserted into the sleeve joint 7 of the column base portion. In the same manner as in the above process, a slight gap is secured between them, and the mold 11 is arranged around them. Then, the upper floor PCa column 5 is joined to the column beam joint by pressurizing and filling the grout 12 into the mold 11 and filling the sleeve joint 7 leading to the gap and the upper part thereof, Thereafter, the above steps are sequentially repeated.

  The composite beam 1 may be joined to the lower-floor PCa column 5 as in the above process, and then the upper-floor construction may be performed again, or as shown in FIG. 8, the lower-floor PCa column. As soon as the composite beam 1 is placed on the upper side, the PCa column 5 on the upper floor is immediately built on the upper part, and the upper and lower gaps of the composite beam 1 and the upper and lower sleeve joints 7 connected thereto are simultaneously filled with the grout 12. Thus, the upper-floor PCa column 5 and the lower-floor PCa column 5 may be simultaneously bonded to the upper and lower sides of the composite beam 1.

According to the joining structure and joining method described above, the composite beam 1 and the PCa column 5 can be securely and firmly joined, and the end of the composite beam 1 functions as a column beam joint (panel zone) as it is. Simple, clear and reasonable.
In addition, it is possible to realize a high degree of PCa for both the beam and the column, and it is possible to introduce prestress without any trouble in advance to the PCa member 3 at the end of the composite beam 1 by the pretension method. Therefore, it is possible to significantly reduce the work on site compared to the case where the beam-column joint is installed on site or prestress is introduced on site using the post-tension method. It is possible to greatly improve the construction efficiency compared to the construction method.

9 to 10 show a second embodiment of the joining method of the present invention.
In the first embodiment, the joining bars 6 for joining the composite beam 1 to the upper and lower PCa pillars 5 are arranged in advance in a state where the joining bars 6 protrude above and below the PCa member 3. In the second embodiment, as shown in FIG. 9, a through hole 13 for arranging the joining bar 6 is provided in advance by embedding a sheath tube in the PCa member 3, and the end of the composite beam 1 is connected to the PCa column 5. In this case, the through-hole 13 is made to coincide with the position of the sleeve joint 7 when it is placed, and then the joining bar 6 is rearranged.
Also in this case, the grout 12 is pressurized and filled in the gap between the PCa member 3 and the PCa column 5, so that the grout is not only inside the sleeve joint 7 but also inside the through-hole 13 connected to the upper part thereof. 12 is filled without a gap, and finally it can be reliably joined as in the first embodiment.
In the second embodiment, as in the case of the first embodiment, the composite beam 1 may be joined to the PCa pillar 5 on the lower floor and then the construction on the upper floor may be performed. Thus, the upper and lower PCa pillars 5 can be simultaneously bonded to the upper and lower sides of the composite beam 1.

FIGS. 11-14 shows 3rd Embodiment of the joining method of this invention.
In the third embodiment, the joining bars 6 are projected in advance so as to protrude above the PCa column 5. That is, the PCa member 3 of the composite beam 1 is provided with a through-hole 13 through which a joining tube 6 can be inserted by embedding a sheath tube in the same manner as in the second embodiment, and at the column head of the PCa column 5 The column main reinforcement 5a is extended greatly upward as it is so as to project upward as a joint 6 that reaches the column base of the PCa column 5 on the upper floor, and the upper end of the joint 6 is connected to the column base of the PCa column 5. The sleeve joint 7 is embedded at the position where the is inserted (see the column base portion of the PCa column 5 on the upper floor shown in FIGS. 13 and 14).
Then, as shown in FIG. 12, the composite beam 1 is placed on the PCa column 5 in a state where the joining bar 6 is passed through the through hole 13 of the PCa member 3, and in the gap between them as in the above embodiment. By filling the grout 12 with pressure, the grout 12 is filled in the gap and the through hole 13 leading to the gap, and the composite beam 1 is joined to the PCa column 5 on the lower floor as shown in FIG. The upper floor PCa column 5 may be built and the upper end portion of the joining bar 6 may be inserted and joined to the sleeve joint 7 of the column base.
Alternatively, as shown in FIG. 14, the composite beam 1 may be placed on the PCa pillar 5 on the lower floor, and the upper PCa pillar 5 may be built on the upper part, and all of them may be joined at the same time.

Although the embodiments of the joining structure and joining method of the present invention have been described above, each of the above embodiments is merely a preferred example, and the concrete configuration of the composite beam and the PCa column, and the concrete of the beam-to-column joint. Needless to say, an appropriate design change and application can be made without departing from the gist of the present invention with respect to such a structure and its construction procedure.
For example, each of the above embodiments is an application example in the case where prestress is preliminarily introduced to the PCa member 3 at the end of the composite beam 1 by a pretension method, but the present invention is limited thereto. Prestress is not necessarily introduced.
Further, since the PCa member 3 in the second embodiment and the third embodiment is formed with the through holes 13 in advance, when prestress is introduced into the PCa member 3 by a pretension method. It should be noted that the through-hole 13 is not deformed by the prestressing force and it becomes difficult to insert the joint muscle 6. Reinforcement may be performed.

DESCRIPTION OF SYMBOLS 1 Composite beam 2 Steel beam 3 PCa member 3a Step part 4 PC steel material 5 PCa pillar 5a Column main reinforcement 6 Joint reinforcement 7 Sleeve joint 8 Large beam (girder direction)
8a Driven formwork 8b Beam main bar 9 Joint bar 10 Sleeve joint 11 Formwork 11a Inlet 11b Outlet 12 Grout 13 Through hole

Claims (7)

When a composite beam having a steel beam as a main body and PCa members made of precast reinforced concrete are integrally formed at both ends thereof, the composite beam is installed between PCa columns made of precast reinforced concrete. A structure for joining a portion to the PCa pillar,
The end of the PCa member in the composite beam is formed as a column beam joint, and the PCa column is formed as a height to the bottom of the beam, and the column of the composite beam is formed at the column head of the PCa column. A joint structure between a PCa column and a composite beam, in which the PCa column and the composite beam are joined through joints placed between the beam joints and arranged between them. A joint structure between the PCa column and the composite beam according to claim 1,
The PCa column and the composite beam are characterized in that the PCa member in the composite beam is pre-stressed in the direction of the axis of the material by embedding a PC steel material in the PCa member. Bonding structure with. A joining method for joining a PCa column and a composite beam by the structure according to claim 1 or 2,
A method for joining a PCa column and a composite beam, comprising the following steps (a) to (d).
(a) The composite beam is pre-arranged in a state where the joint bar penetrates the column beam joint part in the vertical direction, and the PCa column has the joint bar on the column head and the column base, respectively. A step of burying a sleeve joint into which an end is inserted,
(b) placing the column beam joint on the column head of the PCa column, and inserting the lower end of the joint bar into the sleeve joint of the column head of the PCa column,
(c) a step of building an upper-floor PCa column on the beam-column joint, and inserting an upper end portion of the joint bar into a sleeve joint of a column base of the PCa column,
(d) A step of filling the sleeve joint with grout and joining the beam-column joint portion of the composite beam and the PCa column via the joint bar. A joining method for joining a PCa column and a composite beam by the structure according to claim 1 or 2,
A method for joining a PCa column and a composite beam, comprising the following steps (a) to (d).
(a) The composite beam is formed with a through-hole for arranging the joint bar in a state where the joint bar is vertically penetrated in the column beam joint, and the PCa column has a column head and a column base. A step of embedding sleeve joints into which the end portions of the joining bars are inserted, respectively,
(b) After placing the column beam joint on the column head of the PCa column, placing the joint bar in the through hole and inserting the lower end thereof into the sleeve joint of the column head of the PCa column ,
(c) a step of building an upper-floor PCa column on the beam-column joint, and inserting an upper end portion of the joint bar into a sleeve joint of a column base of the PCa column,
(d) A step of filling the sleeve joint with grout and joining the beam-column joint portion of the composite beam and the PCa column via the joint bar. A joining method for joining a PCa column and a composite beam by the structure according to claim 1 or 2,
A method for joining a PCa column and a composite beam, comprising the following steps (a) to (d).
(a) The composite beam is formed with a through-hole for arranging the joint bar in a state where the joint bar is vertically penetrated in the column beam joint, and the PCa column has the joint at the column head. The bar is provided so as to protrude upward so as to reach the column base of the PCa column disposed on the upper floor, and a sleeve joint into which the upper end of the joint bar is inserted is embedded in the column base. The placing process,
(b) placing the beam-column joint on the column head of the PCa column, and at that time, allowing the joint bar to penetrate the through hole;
(c) a step of building an upper-floor PCa column on the beam-column joint, and inserting an upper end portion of the joint bar into a sleeve joint of a column base of the PCa column,
(d) A step of filling the sleeve joint with grout and joining the beam-column joint portion of the composite beam and the PCa column via the joint bar. A method for joining a PCa column and a composite beam according to claim 3, 4 or 5,
The sleeve communicated with the gap through the gap by filling the gap between the beam-column joint portion of the composite beam and the column leg portion and the column head portion of the PCa column joined to the upper and lower sides thereof. A method of joining a PCa column and a composite beam, characterized by filling the joint with grout. A method of joining a PCa column and a composite beam according to claim 4 or 5,
The sleeve communicated with the gap through the gap by filling the gap between the beam-column joint portion of the composite beam and the column leg portion and the column head portion of the PCa column joined to the upper and lower sides thereof. A method for joining a PCa column and a composite beam, wherein the joint is filled with grout, and the through hole communicating with the grout from the gap is filled with grout.

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