JPS6231148B2 - - Google Patents

Description

[Detailed description of the invention]

In general, earthquake-resistant walls in an earthquake-resistant structure contribute to the strength of a building, and their main role is to prevent deformation of the building through the rigidity of the wall. Conventional reinforced concrete structures with seismic construction have the advantage of very high resistance and high initial rigidity, but they lack deformation performance and, in the rare event of a large earthquake, small gaps between the framework layers are formed before the framework reaches its maximum strength. The major drawback is that deformation causes brittle fractures, leading to a sudden drop in strength, often leading to building collapse. The present invention has been proposed in view of the above circumstances, and provides a low-strength structure having arbitrary thickness and height in a part surrounded by a frame made of reinforced concrete, steel-framed reinforced concrete, or steel columns and beams. A sandwich-shaped reinforced concrete wall element composed of a wall board core material made of concrete or clay, and a wall board surface material made of normal or high strength concrete or mortar, and a normal or high strength reinforced concrete wall element, They are arranged alternately with arbitrary widths in the direction of the beams of the framework, and both the wall elements are integrally connected, and each of the upper and lower ends of the sandwich-like reinforced concrete wall element and each of the upper and lower beams are connected to each other. Leave a space between
The shear wall is characterized in that the normal or high-strength reinforced concrete wall elements are arranged between the same space, and both the wall elements are integrally connected. The building's rigidity is increased to reduce the deformation of the building against the wind pressure and the small earthquakes that often occur.In the case of a large earthquake that rarely occurs, the building's rigidity is increased to maintain an appropriate resistance strength and to maintain the rigidity of the building in response to large deformations. The object of the present invention is to provide a shear wall that can reduce seismic input by lowering the earthquake resistance, and improve the seismic performance of a building through a joint effect with the frame. Note that low-strength concrete has a compressive strength of approximately 80~
Concrete has a compressive strength of 150Kg/ ^cm2 or less, and ordinary concrete has a compressive strength of about 200Kg/cm2.
cm ² - 240Kg/cm ² concrete, high-strength concrete is concrete with a compressive strength of about 240Kg/cm ² or more. In the case of conventional one-piece reinforced concrete shear walls, the strength of the concrete wall plate is greater than the shear strength of the surrounding frame, and in the event of a large earthquake, the truss-like compressive drag of the wall plate would impart excessive shear force to the frame. It causes brittle fracture and poor deformation performance. In addition, if the frame around the wall plate is very strong, the wall plate will fail before the frame without shear failure, and the deformation performance of the shear wall will be slightly improved compared to the case where the surrounding frame fails in shear. However, since ordinary or high-strength concrete itself is a material with poor compressive toughness, no significant improvement in deformation performance can be expected, and the yield strength against repeated shearing stress is significantly reduced, resulting in poor deformation performance compared to frame deformation. It doesn't change the fact that it is a thing. As described above, the seismic resistance according to the present invention is characterized by a wall made of low-strength concrete or clay having an arbitrary thickness and height in a part surrounded by a frame made of reinforced concrete, steel-framed reinforced concrete, or steel columns and beams. A sandwich-like reinforced concrete wall element composed of a plate core material and a wall plate surface material made of ordinary or high-strength concrete or mortar, and an ordinary or high-strength reinforced concrete wall element are arranged in the beam direction of the framework. The wall elements are arranged alternately with arbitrary widths, and the two wall elements are integrally connected, leaving gaps between the upper and lower ends of the sandwich-like reinforced concrete wall element and the upper and lower beams. , normal or high-strength reinforced concrete wall elements are placed between the two, and both wall elements are integrally connected, so it is resistant to wind pressure during normal times and small earthquakes that often occur. Like a one-piece shear wall, the entire wall increases the rigidity of the building, effectively working to improve the safety of the building, and in the rare event of a large earthquake, it resists the compressive drag of the wall plate like a truss. Therefore, first, the sandwich-like reinforced concrete wall elements containing low-strength core materials will gradually fail, avoiding brittle shear failure of the surrounding framework, and the normal or high-strength reinforced concrete wall elements will gradually become mainly subject to wall-column-like bending. As a resistance member, it adapts to the deformation of the surrounding frame, and as a seismic wall, it has a large deformation capacity with little reduction in proof strength. In this case, the low-strength wall board core material is shown in Table 1 and 2 below.
By using a material with high compressive toughness and little loss of strength as shown in the figure, the sandwich-like reinforced concrete wall elements will gradually break down, but at the same time the loss of yield strength will be small, and at the same time, ordinary or high-strength reinforced concrete wall elements will be destroyed. As the restraint of the element weakens as the sandwich-like reinforced concrete element progresses, it smoothly transforms into a resistance member that mainly performs wall-column bending. It has a large deformation ability. Moreover, the strength, rigidity, and deformation performance of the shear wall according to the present invention can be achieved by adjusting the thickness, strength, and height of the core material of the sandwich-shaped reinforced concrete wall element, and Adjustment is also possible by adjusting the width of the wall elements and the normal or high strength reinforced concrete wall elements. As described above, the shear wall according to the present invention has appropriate rigidity and toughness to withstand deformation as a shear wall, has an appropriate shearing force within the elastic limit during a weak earthquake, and has relatively high rigidity. It functions as a shear wall, and during strong earthquakes, it gradually becomes more plastic than the sandwich-like reinforced concrete wall element with a low-strength core material, reducing its rigidity, and resists external forces through the bending resistance of the normal or high-strength reinforced concrete wall element. As a result, the rigidity of the wall element gradually decreases, and the wall element cooperates with the surrounding columns and beams to resist external forces until they yield. When ordinary or high-strength reinforced concrete wall elements change to a resistance mechanism mainly based on bending resistance during large deformations, rocking behavior occurs and excessive local shear forces are generated in the upper and lower beams. In order to alleviate this problem, in the present invention, a space is provided between the upper and lower ends of the sandwich-like reinforced concrete wall element having a low-strength core material and each of the upper and lower beams. By providing a body part,
Appropriate shear reinforcement is provided. The present invention will be described below with reference to the illustrated embodiments. Figures 1A, 1B, and 1C show reinforced concrete columns 1a and beams 2a made of ordinary or high-strength concrete, steel-framed reinforced concrete columns 1b and beams 2b, and steel columns 1c and beams 2c within a framework, respectively. A sandwich-like reinforced concrete wall element 3 composed of a wall board core material made of low-strength concrete or hardened clay, etc. and a wall board surface material made of normal or high-strength concrete or mortar, and a normal or high-strength reinforced concrete wall. The wall elements 4 are arranged alternately with an arbitrary width, and the two wall elements 3 and 4 are integrally connected, so that the upper and lower parts of the sandwich-like reinforced concrete wall element 3 having a low-strength wall core material are A space is provided between the end portion and each of the upper and lower beams, and a normal or high-strength reinforced concrete wall element 4 is placed in the space, and the wall element 4 is integrally connected to the wall element 3. do. Note that each of the wall elements 3 and 4 may be arranged in the opposite direction to that shown in the drawings, and the number and width of the wall elements 3 and 4 may be arbitrarily determined in consideration of the strength and rigidity of the earthquake-resistant wall. It is also possible to use the entire wall board as a precast material and connect it to the surrounding frame via joints and joints. Table 1 below shows materials suitable for the wall board core material of the sandwich-shaped reinforced concrete wall element 3, which were obtained as a result of experiments by the present inventors, and Fig. 2 shows stress-strain curves of each material. This shows that.

[Table] In Figure 2, 8 is normal strength concrete. Figures 3 to 6 show an embodiment in which the present invention is applied to a cast-in-place reinforced concrete frame or a steel reinforced concrete frame, in which a precast low-strength concrete wall core material 6 is arranged between wall reinforcements 5 in the frame. Then, concrete is poured together with the columns 1a, 1b and beams 2a, 2b, and a sandwich-shaped reinforced concrete wall element 3 is formed at the location where the core material 6 is installed, and the remaining part is made integral with the wall element 3. to form a normal or high-strength reinforced concrete wall element 4. In addition, Fig. 3 shows the case where the wall core material is arranged within the normal wall reinforcement arrangement, Fig. 4 shows the case where the wall core material is arranged within the wall column reinforcement arrangement, and Fig. 5 and Fig. 6 show the case where the wall core material is arranged within the wall reinforcement arrangement. This figure shows a simplified wall reinforcement arrangement. Figure 9 shows the results of an experiment conducted to confirm the seismic effect of the mechanical properties of the shear wall according to the present invention, R _W is reinforced concrete or a concrete shear wall integrally cast within a steel reinforced concrete frame In this case, F is only the skeleton, R _W
1 , R _W2 and R _W3 indicate the case where sandwich-shaped reinforced concrete wall elements 3 are installed as shown in the figure, and ordinary monolithic shear walls R _W do not suddenly lose their bearing strength once the maximum bearing strength is exceeded. The load will have to be shared by the surrounding framework. At this time, if the frame does not have sufficient strength, the surrounding frame will be destroyed at the same time as the wall plates, and the earthquake-resistant wall will undergo what is called a sudden failure, which is not desirable in terms of earthquake-resistant design. In addition, in a normal one-piece shear wall,
The surrounding frame cannot support the compressive drag of the wall plate as a brace, and even if it can support it, the concrete for the wall plate lacks toughness, resulting in a sudden drop in yield strength. On the contrary, the shear wall of the present invention has R _W1 in FIG.
As shown in R _W2 and R _W3 , at the stage of small deformation, the rigidity is close to that of conventional integrally cast shear walls, and in rare cases of large earthquakes, the low-strength wall core material is first weakened by the transformer-like compressive drag of the wall plate. Cracks occurred in sand German trench-like reinforced concrete wall elements, including
In addition to gradually crushing and avoiding brittle shear failure of the surrounding frame, ordinary or high-strength reinforced concrete wall elements resist external forces through bending resistance, and the stiffness of the wall elements gradually decreases, causing surrounding columns, It works together with the columns and beams to resist external forces until the beam yields. Although the present invention has been described above with reference to embodiments, the present invention is, of course, not limited to such embodiments, and can be modified in various designs without departing from the spirit of the present invention. .

[Brief explanation of the drawing]

Figures 1A, 1B, and 1C are front views showing the case where the present invention is applied to reinforced concrete structures, steel reinforced concrete structures, and steel frames, respectively, and Figure 2 is a low-strength structure used in the present invention. 3 to 6 are vertical sectional views showing other embodiments of the present invention, and FIG. 7 is a compressive stress-strain curve of concrete.
8 and 8 are the arrow-view and arrow-view views of FIG. 3, respectively, FIG. 9 is the load-deformation curve of each shear wall according to the conventional and the present invention, and FIG. FIG. 3 is a front view of the various shear walls and frames shown. 1a, 1b, 1c...column, 2a, 2b, 2c...
...Beam, 3...Sand Germany reinforced concrete wall element, 4...Ordinary or high strength reinforced concrete wall element.

Claims (1)

[Claims] 1 Reinforced concrete, steel reinforced concrete,
Or a wall made of ordinary or high-strength concrete or mortar with a wall plate core made of low-strength concrete or clay having an arbitrary thickness and height in a part surrounded by a framework made of steel columns and beams. Sandwich-like reinforced concrete wall elements composed of plate surface materials and normal or high-strength reinforced concrete wall elements are alternately arranged with arbitrary widths in the beam direction of the framework, and both of the above-mentioned The wall elements are integrally connected, gaps are provided between the upper and lower ends of the sandwiched reinforced concrete wall elements and the upper and lower beams, and the ordinary or high-strength reinforced concrete wall elements are arranged in the gaps. A quake-resistant wall characterized in that the both wall elements are integrally connected.