JPH0594342U - Structure of the true pillar - Google Patents

Abstract

(57) [Abstract] [Purpose] To improve the structure of steel structural columns that support the upper structure and connect it to the upper structure during the underground construction by the reverse construction method. [Structure] In a steel structure true pillar 10 included in a reinforced concrete underground pillar 7, the true pillar 10 is a steel pipe having a square cross section that is rooted in a concrete pile 4 installed in advance in the pile hole 3. 11 and the concrete 12 filled in the steel pipe 11, which is installed with a deflection of 45 degrees with respect to the center axes x and y of the general columns 7 of the structure, thus improving the anchoring of the reinforcing bar 81 of the beam 8. ing.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a structure of a steel-framed structural column installed for a steel-framed reinforced concrete building, and in particular, a concrete-framed steel framed structure is constructed by placing concrete in a pile hole excavated from the ground surface. To improve the structure of the true columns when supporting the upper structure during underground construction.

[0002]

[Prior Art]

 A method is known in which a building is made of steel-framed reinforced concrete, and when it is supported by foundation piles below the basement, a column of steel frame precedes the column of the basement and this column is constructed as a true column. As shown in Fig. 4, when supporting a steel-framed reinforced concrete building 1 with a foundation pile below the basement 1a, firstly, a pile hole 3 is excavated from the upper surface of the ground 2 and then below the basement 1a. A cast-in-place pile 4 is constructed on the pile, and the structural pillars 5 are hung on the pile 4 and erected. The structure column is made of steel and uses a simple frame with a frame structure on the top surface, and while keeping the suspended structure column on it, it depends on maintaining the verticality of the suspension of the structure column itself. Then, perform accurate centering on the pedestal, and insert the bottom end into the pile 4 for accurate installation. Next, the pile hole 3 is backfilled with crushed stone, earth and sand 2a, etc., and the base 6 including the floor and the beam on the first floor is constructed on the ground surface. While excavating the basement 1a part under the support, the pillar 7, The structure of the beam 8 can be sequentially constructed from the upper side by the so-called upside down construction method, while the structure pillar 5 installed as a temporary structure supports the load of the upper structure 1b of the building 1 during that time. Construction can proceed in parallel with the underground.

[0003]

[Problems to be solved by the device]

 However, although the true column is based on the principle of verticality when suspended, in reality, displacement and bending cannot be avoided if a simple pedestal is used, and there is a limit to the accuracy of the position at the bottom. As a result of the centering, not only a large error is often caused, but also there are drawbacks such as contact and catching with the reinforcing bars of the foundation piles that are separately inserted and installed. Also, if the true structural column and the reinforcing reinforcing bar are integrally assembled and inserted, the accuracy of the true structural column depends on the position of the reinforcing reinforcing bar, and the center of gravity of itself changes, impairing the verticality of suspension. It was a thing.

In any case, since the structural columns are connected to the above-ground structure and it is important to ensure accuracy, they are installed as a temporary structure until the underground column is completed, which is economically feasible. It is desirable that the conditions be simple, structurally reasonable as a member with a large axial force and a small bending, and also with good workability and safety.

[0005]

[Means for Solving the Problems]

 In view of the above situation, the present invention was devised to solve the problem as a problem to improve the structure of the structural column, and in the structural column of the steel frame structure included in the reinforced concrete underground column. , The structural column consists of a steel pipe with a square cross section that is embedded in a concrete pile that is installed in advance in the pile hole and concrete that is filled in the steel pipe, and each side of the steel pipe is It is characterized in that it is installed with a deflection of 45 degrees with respect to the center line of a general pillar, and also discloses a beam connection structure when a concrete structure is constructed by the above structure. is there.

Therefore, according to the present invention, by using the steel tube concrete construction for the structure columns, the total cross-sectional area of the structure columns is small, and the wall thickness of the steel pipe can be reduced. Moreover, not only the axial deformation becomes smaller and the compulsory deformation stress of the frame becomes smaller, but also the surface is smooth due to the closed section of the steel pipe, and it is possible to easily clean the adhesion of earth and sand. The most important feature is that the true column is deflected by 45 degrees around the axis with respect to the normal core of the ground structure. , The structure of the beam to be connected with it is not limited to steel frame construction. In addition, the reinforced concrete beams have the advantage that the main bars are horizontally divided at the ridges of the structural columns and can be easily and sufficiently anchored on both sides inside the columns of the underground structure. ing. In addition, the true-post pillars, which are installed with a 45-degree deflection, have greater resistance to twisting around the axis than the cruciform true-post pillars when inserting concrete into the foundation piles, and the accuracy is maintained. ing.

[0007]

【Example】

 The present invention will be described in detail with reference to the drawings showing a preferred embodiment in which the structure of the true pillar of the present invention is adopted. FIG. 1 is a horizontal sectional view of a true column at the top of a basement structure adopting the present invention, and FIG. 2 is a horizontal sectional view of a joint between a column and a beam at the installation position of the true column. As shown in FIG. 4, in the basement 1a portion of the building 1 made of steel-framed reinforced concrete, the structure is located above the cast-in-place pile 4 which is constructed below the basement 1a in the pile hole 3 excavated from the ground surface. A true pillar 5 is erected, and a pillar 7 of the structure of the basement 1a and a beam 8 connected to the pillar 7 are formed around the true pillar 5 by the reverse construction method as shown in FIGS. Be built. Reference numeral 9 is concrete that forms the pillars 7 and the like. The reference numbers in FIG. 4 are common to the corresponding members.

According to the present invention, in order to install the true pillar, first, the pile hole 3 for the pile 4 is excavated from the ground by a known method, and when deep excavation, the mud circulation method is usually adopted. The hole 3 is filled with muddy water. The conventional true column 5 is installed not only in a circular shape but also in a cross shape or an H shape according to the coordinate axes x and y of the pillar 7 which is aligned with the core of the building. The prismatic prism 10 is adopted with a deflection of 45 degrees with respect to the core. The true column 10 is composed of a steel pipe 11 having a rectangular cross section and concrete 12 filled in the steel pipe 11. Each side 13 in the cross section of the steel pipe 11 is 45 degrees with reference to the coordinate axes x and y of the pile 2. It is installed with a bias. Reference numeral 20 is a steel column above the ground.

Next, FIG. 2 is a plan view of the joint portion between the underground pillar 7 and the beam 8 at the installation position of the structural pillar 10, and shows the crossing state of the reinforcing bars of the beam 8. The end portion 82 where the beam reinforcing bar 81 in each direction is fixed to the column 7 is horizontally divided along each side 13 of the steel pipe 11 at the ridge angle 14 of the true column 10 and bypasses the ridge angle 14 at the adjacent position. Has been established. Therefore, the bent angle of the swallowed portion of the beam 8 to the column 7 in the diffusion direction is shallow, the transmission of force is smooth, and the beam 8 on the opposite side of the column 7 should be common to the fixing portion. Therefore, it is not necessary to form a horizontal haunch on each beam 8 for the pillar 7.

FIG. 3 is a cross-sectional view taken along the line AA of FIG. 1, and is a vertical cross-sectional view for explaining a connecting portion between the true post 10 and the above-ground steel column 20. The true columns 10 are connected at their tops by the base 6, and the above-ground steel columns 20 are connected above the upper surface thereof. Since the above-ground steel column 20 and the true structure column 10 are mutually biased at 45 degrees at the connecting portion, the base plate 21 is interposed at the transition portion, and they are vertically connected to form a confined structure. In the invention, a connecting steel plate 15 is provided on the top of the true column 10. The connecting steel plate 15 is, for example, in the shape of a bracket, and is configured to support the lower surface of the base plate 21 vertically from the central portion of each side 13 of the steel pipe 11. In addition, the concrete 12 inside the structural column 10 is connected to the concrete 23 that fixes the lower end of the above-ground steel column 20 through the opening 22 at the center of the base plate 21. Reference numeral 24 denotes a stiffener for the column 20, which facilitates transmission of stress of the flange of the beam 25 within the cross section of the column 20 together with the base plate 21 when the steel frame beam 25 of the base 6 is installed on the column 20.

[0011]

[Work]

 The operation of the structured column 10 configured as described above will be described. Since the steel pipe 11 is filled with concrete 12, the structure is made of steel-framed concrete, so that it has a cross section that is more substantial than that of a single steel-framed structure. , Even if the floor height of the true column 10 in the basement is high, it does not buckle under the supporting load. In addition, since the outer surface of each side 13 of the steel pipe 11 is formed smooth, when the inside of the pile hole 3 is once backfilled and the pillar 7 is constructed by the reverse construction method, the steel pipe is used for placing concrete in the pillar 7. Even in the step of cleaning the surface of 11, the work is easy because of the closed cross section.

Next, since each side 13 in the cross section of the steel pipe 11 of the true-column 11 is installed by being deflected by 45 degrees with reference to the coordinate axes x and y of the column 7 of the structure, FIG. As shown in, the end portion 82 where the beam rebar 81 of each direction of the beam 8 is fixed to the column 7 is divided horizontally along each side 13 of the steel pipe 11 at the ridge angle 14 of the true column 10. It is fixed by bypassing the adjacent ridge angle 14. Therefore, the bent angle of the swallowed portion of the beam 8 to the pillar 7 is shallow, the force can be transmitted smoothly, and it can be shared with the fixing portion of the beam 8 on the opposite side of the pillar 7. As a result, it is not necessary to form a horizontal haunch on each beam 8 for the pillar 7.

In the embodiment of the present invention, configurations other than those described above are possible, and as another embodiment, the beam 8 is precast only by projecting the end portion 82 of the beam rebar 81 of the beam 8 outward. It is significant in that the difficulty of forming a horizontal haunch is eliminated. Further, when the above-ground steel column 20 does not have a closed cross section, the top of the true column 10 penetrates through the opening 22 of the base plate 21 and faces the lower end of the above-ground steel column 20. Can be fixed to each other so as to form a structure, and the structure for vertically connecting the filled concrete 12 in the structural column 10 and the fixing concrete 23 at the lower end of the above-ground steel column 20 does not change.

[0014]

[Effect of the device]

 The structure of the structure column of the present invention is a reinforced concrete underground column including the structure column of steel frame, and the structure column has a square section steel pipe installed in advance in the pile hole and a steel pipe inside the steel pipe. It is composed of concrete to be filled, and the installation angle of the structure column is deviated by 45 degrees with respect to the center of the general column of the structure. Due to the advantage of the installation angle of 45 degrees being deflected, the performance as a true column is significantly improved. In addition, since the structure column is connected to the above-ground structure, it is important to ensure accuracy, but it will be installed as a temporary structure until the underground structure is completed. Is simple, and is structurally rational as a member with a large axial force and small bending, and is also highly workable and safe.

In particular, by using the steel tube concrete structure as the structure column, the total cross-sectional area of the structure column is small, the wall thickness of the steel pipe can be reduced, and the axial deformation is also small. Not only the forced deformation stress becomes small, but also the surface is smooth due to the closed cross section of the steel pipe, which makes it easy to clean the adhesion of sediment. A further significant feature is the fact that the true column is deflected by 45 degrees around the axis with respect to the normal core of the structure, which means that the true column is not adopted. However, the structure of the beam to be connected with it is not limited to the steel frame structure.In a beam with a reinforced concrete structure, the main bar is divided horizontally at the ridge angle of the true structural column, and the main bar is divided into both sides within the cross section of the column. It has an advantage that it is easily and sufficiently fixed. In addition, the true post, which is installed with a 45-degree deflection, has higher resistance to twisting around the axis than the cross-like true post in the preceding concrete foundation pile, and accuracy is maintained. Therefore, according to the present invention, when constructing an underground pillar including a true pillar, the true pillar is properly installed, which greatly contributes to the reduction of the cost of the true pillar itself, and moreover, the beam connected to the pillar. It has a very significant epoch-making effect on the construction method of the part.

[0016]

[Brief description of drawings]

FIG. 1 is a horizontal sectional view of a true column at the top of a basement structure adopting the present invention.

FIG. 2 is a horizontal cross-sectional view of a joint portion between a pillar and a beam at an installation position of the true pillar.

FIG. 3 is a vertical cross-sectional view taken along the line AA of FIG. 1 for explaining a connecting portion between the true post and the above-ground steel column.

FIG. 4 is a vertical sectional view for explaining a conventional structural pillar method.

[0017]

[Explanation of symbols] 1 building 1a basement 1b upper structure 2 ground 2a crushed stone, earth and sand, etc. 3 pile holes 4 piles 5 true columns 6 foundations 7 columns 8 beams 9 concrete 10 steel columns 12 steel pipes 12 concrete 13 Each side of steel pipe 14 Ridge angle 15 Connection steel plate 20 Ground steel column 21 Base plate 22 Opening 23 Concrete 24 Stiffener 25 Beam 81 Beam rebar 82 End part

Claims (3)

[Scope of utility model registration request] 1. A steel structure structure column included in a reinforced concrete underground column, wherein the structure column is a steel pipe having a square cross section that is rooted in a concrete pile installed in advance in a pile hole. It consists of concrete filled inside and each side of the steel pipe is 4 with respect to the core of the general pillar of the structure.
The structure of a true pillar, which is installed with a 5 degree deflection. 2. The beam to be joined to the underground column is made of reinforced concrete, and the reinforcing bar is fixed by being divided horizontally in the section of the underground column by the ridge angle of the true column. The structure of the true pillar according to claim 1. 3. The structure of the true pillar as claimed in claim 1, wherein the top of the true pillar is connected to the ground pillar through a steel base plate of the ground pillar.