(1) Full-section wall refers to a solid wall without holes or a shear wall with holes, and its stress state is similar to that of a vertical cantilever member. When the height-width ratio of shear wall is large, the cross section remains flat after bending deformation, and the normal stress is linearly distributed.
(2) The whole small opening wall refers to the shear wall with a slightly larger opening and a columnar distribution. The normal stress on the section slightly deviates from the straight line distribution, which is equivalent to the superposition of the straight line distribution of the whole bending moment and the local bending moment stress of the wall limb. The local bending moment of the wall limb is generally not more than 15% of the total bending moment, and the wall limb of most floors has no bending point.
(3) Even the wall parts refer to the large openings arranged in rows, so that the rigidity of the coupling beams is much smaller than that of the wall limbs. There is a bending point in the middle of the coupling beam, and each wall limb plays a significant role independently, which can be regarded as a shear wall formed by connecting several single-limb shear walls through the coupling beam. When there is a row of holes, it is a double-limb wall, and when there are multiple rows of holes, it is a multi-limb wall.
(4) Wall-type frame, when the hole is wide and the width of the wall limb is relatively small, and the stiffness of the wall limb is not too far from that of the coupling beam, the mechanical performance of the shear wall is similar to that of the frame structure; It is characterized by obvious local bending moment in the normal stress distribution of the wall limb section, and many floors have anti-bending points.
Second, the layout of shear wall shall meet the following requirements:
(1) Shear walls should be arranged in two or more directions and aligned. Shear walls in different directions should be connected separately to avoid the structural arrangement of walls in only one direction. When shear walls are arranged in two directions and connected with each other, the longitudinal wall can be used as the flange of the transverse wall, thus improving its bearing capacity and stiffness.
(2) In the earthquake area, the shear wall is designed as a wall with high aspect ratio H/B because of its low wall. (H/B& lt； 1.5) is shear brittle failure with poor seismic performance. Therefore, when the shear wall is long, the floor slab (without coupling beam) or coupling beam with span-height ratio not less than 6 can be used to divide it into several independent wall segments. Each independent wall section can be a solid wall, a whole small opening wall, a conjoined wall or a wall-type frame, and the H/B ratio of each independent wall section should not be less than 2, and the length of the wall limb should not be more than 8m. When the building height is not very large, in order to make the building stiffness of the whole shear wall structure appropriate, in addition to the seismic grade I, shear walls composed of most short-leg shear walls can also be used. Short-leg shear wall refers to the shear wall with the ratio of section height to section thickness of 5-8 and the wall thickness of not less than 200 mm This kind of shear wall has been widely used in recent years because of its larger height and width, better ductility and energy dissipation capacity than ordinary walls.
(3) Shear walls with staggered holes and unreasonable openings have poor mechanical and seismic performance. The doors and windows of shear walls should be aligned up and down and arranged in columns to form clear wall limbs and coupling beams. In seismic design, shear walls with seismic grade I, II and III should not be staggered walls. When staggered hole walls must be used, the staggered distance of holes should not be less than 2m in both horizontal and vertical directions. In order to avoid uneven stiffness and weak wall limb, the ratio of height to thickness of wall limb section should not be less than 4.
(4) Shear walls should be arranged continuously from top to bottom, and should not be suddenly interrupted to avoid sudden stiffness change.
(5) Control the out-of-plane bending moment of shear wall. When the shear wall is connected with the floor beam out of the plane of the wall, and the beam height is greater than the wall thickness, at least one of the following measures can be taken:
1) The shear wall connected with the beam is set along the beam direction to resist the out-of-plane bending moment.
2) It is advisable to set buttress at the intersection of wall and beam. The section and reinforcement of buttress shall be determined according to calculation.
3) Embedded columns should be set at the intersection of wall and beam, and reinforcement should be determined according to calculation.
4) When the floor beam connected to the shear wall is a steel beam, it is appropriate to set a steel beam in the shear wall.