JPH0438869B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a shear wall for a steel-framed reinforced concrete structure, and more specifically, in a steel-framed reinforced concrete structure, a steel member installed as a temporary member is This paper relates to steel-framed reinforced concrete composite shear walls, which are also used in the earthquake-resistant structural design of objects.

[Prior Art] In large steel reinforced concrete buildings such as nuclear reactor buildings or turbine buildings, a large number of steel members are used as temporary members necessary for construction during the construction process. For example, in order to proceed with construction work regardless of the weather, an all-weather construction method has been proposed in which a temporary structure is erected above the structure and construction proceeds inside. . This construction method will be explained with reference to FIG. In the construction of the reactor building structure 1, a roof dome 5 is constructed at the upper center of the lower building 4 in order to install the reactor 3 on the base 2. The roof dome 5 is made up of a roofing material 5A made of an air membrane structure, pillars 6 that support it, and a membrane-like wall 7 that covers the outer periphery. The pillars 6 are erected at the outer circumferential wall of the structure 1 to support the roofing material 5A, and are equipped with a lifting machine 8 in the middle for use in lifting and transporting within the construction site. 9 indicates other mechanical equipment;
In the figure, a monorail crane is shown to represent them. In this way, under the construction of the roof dome 5, the construction of the building 1 can proceed without being affected by the weather. The roofing material 5A, pillar material 6, wall body 7, etc. are temporary facilities for the permanent construction work of the building 1, and the structural design of the pillar material 6 is based on the load and lift of the roofing material 5A. The function as the base of the heavy equipment 8 and the wind pressure to which the membrane wall 7 is subjected are fully considered, and it is established as an independent structure.
Only pillar material 6 remains after removing roof material 5A.
It is designed to remain within the frame structure of Building 1.

[Problems to be solved by the invention] In the construction of nuclear power-related facilities, the total amount of work is absolutely large, and the amount of steel used for steel frames and reinforcing bars is enormous. The addition of the pillars 6 and walls 7 for the roof dome 5, which are temporary members, poses a problem that may affect the characteristics of the all-weather construction method from the perspective of construction materials. That is, as shown in FIG. 6, when constructing an earthquake-resistant frame with earthquake-resistant walls 40 incorporating braces 30 in a frame structure consisting of columns 10 and beams 20, In this drawing, the reinforcing bars of the column 6 are embedded in concrete to form the column 50. Although the pillars 6 are structurally designed as temporary members in the out-of-plane direction in FIG. Although it is a non-negligible amount, it does not contribute to the structural design at all as a steel material for permanent construction work. Moreover, the fact that no attempt is made to recover the materials as temporary construction materials has a major impact on the materials, which in turn has a major impact on the construction costs of the reactor building.

[Means for Solving the Problems] The present invention aims to solve the above-mentioned problems in the construction work of nuclear reactor buildings when all-weather construction methods are adopted, and has been achieved through extensive research. Even if it is a pillar material for temporary equipment, the steel members that will remain in the permanent structural frame are calculated based on the earthquake-resistant structure and adopted in the design. The purpose of this project is to consider the steel frame in the frame plane together with the concrete in the structural design, and to create a shear wall made of a composite structure made of steel and reinforced concrete. The steel-frame reinforced concrete composite shear wall of the present invention forms a rib-shaped shear resistance material across the web and flange of the steel frame, and generates the same interlocking effect as deformed reinforcing bars on the steel frame. It is characterized by forming a shear wall that functions as a composite material in concrete.

[Example] The steel-framed reinforced concrete composite shear wall of the present invention will be described in detail based on the drawings of the example. Figure 5,
The reference numbers in FIG. 6 are the same for the corresponding parts. FIG. 1A is a vertical sectional view of the steel reinforced concrete composite shear wall of the present invention, and FIG. 1B is a horizontal sectional view taken along line A-A in FIG. 50, the pillar material 6 of the above-mentioned roof dome 5 remains in the frame structure, and a steel reinforced concrete pillar is formed therein. In a building 1 such as a nuclear reactor building, pillar material 6
Since H-beam steel is generally used, the concrete is bisected by the steel web and shear forces are not transmitted, as shown in Figure 2a. Figure b shows the interlocking effect of ribs in deformed reinforcing bars.

In the present invention, the pillar material 6 is newly given a reference numeral 60, its flange is designated 61, and its web is designated 62.
63 are both flanges 61 of the steel column material 60 in the figure,
It is a rib-shaped steel plate welded horizontally across the web 62, and its thickness is equal to that of the flange 61, so that when the steel column 60 is buried in the concrete 70, the relationship between the steel frame and the concrete increases. It is a shear-resistant material that produces the effect of integration through interlocking. The shear resistance materials 63 are arranged at approximately equal intervals in the axial direction of the steel column material 60, and in the embodiment, 1.5
It is designed not to exceed m. The columns 10 and beams 20 of the building 1 in FIG.
0, 80 is a wall, and 90 is a concrete slab.

[Function] The function of the steel reinforced concrete composite shear wall of the present invention will be explained based on the construction process. Figure 3 is a schematic diagram illustrating a composite structure of concrete and steel frames, Figure 4 is a schematic elevation view showing one aspect of the framework in Figure 6, and Figures a to c are explanations of structural analysis. It is a diagram. In FIG. 3, a steel column 60 is embedded in concrete 70, and a web 62 and shear resistance material 63 are shown in cross-section. When shear force acts between the concrete 70 and the steel column 60, the meshing effect between the two causes the steel column 60 to
As shown in the figure, an axial stress is generated from behind the shear resistance material 63, but this stress gradually decreases toward the adjacent shear resistance material 63, and when the distance a between them is not large, the average value It can be considered as t. Therefore, the steel column material 60 can be considered to be a fully reinforced member like deformed reinforcing bars, and the steel column material 60 can be effectively employed in structural design.

On the other hand, the load-bearing mechanism of reinforced concrete shear walls is
Think of it as a "beam"-like shear reinforcing bar system, as shown in Figure 4a, and as an "arch"-like concrete pressure field system that connects the ends of the timber, as shown in Figure 4. Since the ultimate strength of a shear wall can be considered separately, it is possible to calculate the resistance by adding the two together. Based on this idea, the above a,
The strength of the shear wall can be calculated by adding the truss effect mechanism shown in Fig. c, which is formed by the steel column material 60 having the shear resistance material 63, to the shear resistance mechanism shown in Fig. b. The method is established. The above idea ensures balance of forces in the final state, and no part exceeds the ultimate strength of the constituent materials.
Since deformation and force balance are ignored, a lower limit value is given, resulting in an evaluation on the safe side.

A trial calculation of an actual design example having the frame shown in Fig. 6 shows that the amount of steel used by calculating the design strength of the steel column 60 as a structural material is compared to the conventional method without calculation. A savings of about 40% was possible, and by calculating the ultimate strength, a comparison that took into account the steel frame within the shear wall showed that the strength could be expected to increase by about 30%.

[Effects of the Invention] The present invention provides the following effects when an all-weather construction method is adopted in the construction of a large structure such as a nuclear reactor building.
By attaching shear resistance materials to steel members that are required for construction but not evaluated in structural design, they can be combined with concrete and used as reinforcement materials, and furthermore, such steel members can be analyzed within shear walls. , and constructed a steel-framed reinforced concrete composite shear wall, which significantly improved the material economy of using steel, both in terms of effective use of steel and the structure of the shear wall. It was a success. In particular, we will disclose an epoch-making invention that not only eliminates problems when adopting all-weather construction methods for the construction of large structures such as nuclear reactor buildings, but also enhances its features. Therefore, as long as the application of such technology is possible, it is not limited to the example of temporary roof supports, but can also be applied to general structural steel materials, and is suitable for all construction work. This can be very good news, and contributes to the economy of steel usage.
This invention can be said to be truly useful for the construction industry.

[Brief explanation of drawings]

The drawings show embodiments of the present invention.
Figure a is a detailed elevation view of a steel-frame reinforced concrete column, figure b is a cross-sectional view taken along line A-A in figure a, and figure 2
The figures explain the transmission of shear force between concrete and steel, with figure a showing steel frames and figure b showing deformed reinforcing bars. Figure 3 is a detailed view of the steel frame showing a composite structure with concrete, and Figures a, b, and c in Figure 4 are schematic diagrams of the structure to explain the evaluation of the strength of the shear wall. FIG. 5 is a schematic sectional view of a nuclear reactor building explaining the all-weather construction method, and FIG. 6 is a frame diagram of the earthquake-resistant frame of the same building. 1...Building, 5...Roof dome, 6...Column material, 8...Lifting machine, 10...Column, 20...Beam, 3
0... Bracing, 40... Shear wall, 50... Remaining columns,
60... Steel column material, 61... Flange, 62...
Web, 63...shear-resistant material, steel plate, 70...concrete.

Claims (1)

[Claims] 1. In a steel-framed reinforced concrete structure,
A steel-reinforced concrete composite shear wall characterized by welding a shear-resisting material in the form of ribs across flanges and webs of steel frame members, and constructing a shear wall including the steel members within the plane of a steel-reinforced concrete structural frame. . 2. The shear resistance material is a steel plate that has approximately the same thickness as the flange of the steel frame member, and within the arrangement interval,
2. The steel-framed reinforced concrete composite shear wall according to claim 1, wherein the stress distribution in the axial direction of the steel frame member is averaged in the length direction.