JPS6016672A - Earthquake-proof structural element of skeletal structure - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an earthquake-resistant structural element in a steel structure, in which a concrete earthquake-resistant wall is fixed to steel columns and/or VVC via steel hardware.

In conventional steel-framed reinforced concrete or reinforced concrete structures, when a horizontal external force A acts on the structure, columns 1, beams 2, presses 5, and concrete shear walls 4 serve as resistance elements (earthquake-resistant elements) as shown in FIG. are considered, and the structure is composed of these.

However, in the case of a conventional steel structure, the columns 1, beams 2, and presses 3 can be considered as resistance elements against the horizontal external force A, but the concrete shear walls 4 are not added as resistance elements due to deformation performance.

Therefore, in conventional steel structures, compared to steel reinforced concrete or reinforced concrete structures, the column 1 is
) 2. Since the horizontal external force A increases the burden on the press 3, these members become thicker, which has the disadvantage of increasing the cost of the structure.

In order to solve this problem, the present invention aims to provide an earthquake-resistant structural element in which an inexpensive concrete shear wall is introduced into a steel structure.

First, I will explain why concrete shear walls cannot be installed in steel structures.

Let's imagine a steel frame structure (hereinafter referred to as a structure) 5 that uses 4 concrete shear walls (see Figure 1). In this case, when a horizontal external force A acts on the structure 5, the concrete shear wall 4 moves to the steel column 1. Or, since the deformation capacity against external force is smaller than that of beam 2, the entire structure deforms as shown in Fig. 2, and at an early stage when the deformation of structure 5 is relatively small, most of the horizontal external force A is applied to the steel frame. The burden is placed more on the concrete shear wall 4. Then, at this stage, the steel frame part hardly functions as a resistance element against the horizontal external force AVc, and at the same time, an excessive load of 4Vc is applied to the concrete shear wall. This will eventually lead to damage such as cracks 6 appearing in the concrete shear wall 4.

In addition, at the stage when the concrete shear wall 4 is broken and the deformation of the structure has progressed to a certain extent, stress due to the horizontal external force AK begins to act on the steel frame part, but the concrete shear wall 4
is broken, so the function of the concrete shear wall 4 as a resistance element has deteriorated.

Therefore, in steel-framed reinforced concrete or reinforced concrete structures, the relationship holds that the strength elements of the structure are uniform in material, but in steel-framed structures, the materials of the columns/beams and concrete shear walls are different, and the deformation behavior This relationship does not hold because there is a phase difference between the two.

Therefore, it is not possible to introduce concrete shear walls 4 as resistance elements against horizontal external force A into steel structures.

The present invention solves the reason why concrete shear walls cannot be installed in conventional steel structures.

Next, an earthquake-resistant structural element of the present invention will be described in which a concrete earthquake-resistant wall 4 is introduced into a steel structure as a resistance element against horizontal external force Avc.

FIG. 3 shows one embodiment of the present invention. As shown in FIG. The lower end of the concrete shear wall 4 and the beam 2 are connected flexibly by high-strength bolts 8 and 9 through a compound 7 having excellent deformability, and the lower end of the concrete shear wall 4 and the beam 2 are rigidly connected through a bracket 10), thereby forming a structure 5. In this case, even if the concrete shear wall 4 is rigid, the mixture 7 deforms in response to the horizontal external force AIC, so if we consider the part of the concrete shear wall 4 that includes the mixture 7, we can convert the rigid concrete shear wall into a soft concrete shear wall. It turns out. If this structure is adopted, even if the structure is in the elastic region or even in the plastic region, the column 1 will be able to withstand the horizontal external force A! 112 and the concrete shear wall 4 simultaneously exert a resistance force, making it possible to satisfy equation (1) similarly to a steel-framed reinforced concrete structure. This is VC, which allows the function of the concrete shear wall 4 to be demonstrated within the steel structure (see Figures 3 and 4).
.

In addition, in the actual design, it is necessary to set the amount of deformation of the mixture by taking into account the amount of deformation of the steel frame part under stress and the amount of deformation of the concrete shear wall, which corresponds to the design concept of the structure. Further, the yield strength and breaking strength of the mixture must be similarly set in consideration of the amount of deformation.

According to experiments, the chemical composition of the preparation 7 for T-joining the concrete shear wall 4 and the columns 1 and 2 is as follows.

It is good for the design of the structure to adopt articulation limited to C60,596 and Mn150%, and the shape is as shown in Fig. 5, Fig. 6, Fig. 7, etc. in order to improve the deformability. Various shapes can be considered, and it is considered functionally effective to vary the wall thickness. In FIGS. 5 to 7, 7a is a bolt hole, 7b is a bolt pedestal, and 7c is a center portion.

If Formulation 7 is designed with the above-mentioned chemical components, the deformation of Formulation 7 can be followed up to 'Aoo' in the interlayer deformation of the structure, and the seismic standards are fully satisfied not only in the elastic design of the structure but also in the plastic design. be able to. Furthermore, as shown in equation (2), by changing the number of attachments of this mixture 7, it is easy to change the burden ratio of the concrete shear wall 4 to the horizontal external force A, and the overall design of the structure can be changed. It has a degree of freedom.

D;nxNxF/Q-・・・・・・・・・・・・・・・・・・・・・・・・(2) D=Horizontal external force coupling rate of concrete shear wall n: Mixture to be installed on concrete shear wall Number of concrete shear walls N: Number of concrete shear walls F: Resistance of one steel hardware Q: Floor shear force due to horizontal external force Also, if the strength of concrete shear walls is set to be greater than the strength of steel hardware during design, it can be used even in the event of a major earthquake. It is also possible to prevent the occurrence of cracks and destruction of concrete shear walls. When repairing after a major earthquake, it is possible to immediately restore all the resistance elements (earthquake-resistant elements) by leaving the concrete shear walls as they are and replacing only the deformed steel hardware.

Furthermore, another great effect of the present invention is that by using steel hardware between the structural parts of the building structure that have earthquake resistance, a damping effect is produced against the shaking of the building structure during an earthquake. be. Especially in the case of steel structures, this effect can be said to be very large because the deformation capacity of the building is large and the damping is small.

Effects of the present invention? To summarize, the following is a summary.

(1) Introducing an inexpensive concrete shear wall as a resistance element (earthquake-resistant element) against horizontal external forces (2J) It is possible to prevent cracks in the concrete shear wall during small-scale earthquakes.

(3) It has a damping effect on the shaking of the building during an earthquake.

(4) Destruction of concrete shear walls can be prevented in the event of a major earthquake, and repair after an earthquake can be done simply by replacing the deformed steel hardware with good quality steel hardware due to the resistance element (seismic element) of the concrete shear wall. Instant playback can be restored.

(5) There is no need for presses, etc., reducing the overall amount of steel. The area covered with fireproof coating can be reduced.

(6) It can also be used on existing concrete shear walls, providing protection against earthquakes.

(7) It also becomes possible to use it as an earthquake-resistant wall, such as a concrete curtain wall used for external walls.

(8) Since the connection between the pillars or beams and the concrete shear wall is the part where the steel hardware is placed, it is possible to reduce the gap between the other pillars or beams and the concrete shear wall to within approximately 50 mm. Yes, it is easy to apply fireproof coating.

Figure 3.4 shows an example where steel hardware is used between the concrete shear wall and the upper beam, but as shown in Figures 8 and 9, steel hardware is used between the concrete shear wall and the lower beam. It may be used between concrete shear walls and columns.
Furthermore, the same effect can be obtained even if concrete shear walls and columns are used simultaneously between both υ (not shown).

[Brief explanation of the drawing]

Figure 1 is a front view of a steel-framed reinforced concrete or reinforced concrete or steel structure with columns, beams, and concrete shear walls as seismic elements, and Figure 2 shows the state when a horizontal external force acts on the structure in Figure 1. Front view shown, 3rd
The figure is a front view of main parts showing one embodiment of the present invention, and FIG.
Fig. 5.6.7 is a perspective view showing an example of steel hardware; Fig. 8.9 is an overall front view showing a state in which a horizontal external force is applied to the structure;
The figures are front views of essential parts showing other embodiments. 1: Column, 2: 9. 4: Concrete shear wall, 7: Steel hardware agent Takashi Honma Figure 7 Figure 2 Figure 3 4th distribution /

Claims (1)

[Claims] 1. An earthquake-resistant structural element for a steel-frame structure, characterized in that a concrete earthquake-resistant wall is fixed to steel columns and/or beams via steel hardware. z For steel hardware, the amount of C in its chemical composition is α5% or less,
An earthquake-resistant structural element for a steel structure according to claim 1, wherein the Mn content is limited to 50% or less.