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					Structure
Chinese term Name: Wall

English term Name: shear wall

Houses or structures to withstand wind loads or the main cause of the level of seismic
load of the wall. Shear failure to prevent the structure. Also known as wind walls or
shear wall, structural walls. Sub-plane wall and cylinder wall. Plane shear for
reinforced concrete frame structure or plate structure, flat floor slab system. To
increase the stiffness, strength and collapse resistance capabilities, and in some parts
can be cast or precast reinforced concrete shear walls. Cast Wall and the surrounding
beams and columns at the same time casting, overall good. Cylinder wall for high-rise
buildings, tall structures and suspension structure, the elevator, stairways, equipment
and ancillary buildings into the interval walled, cylinder walls are cast reinforced
concrete wall, the stiffness and higher than the plane shear strength to withstand large
horizontal loads.
[Edit this section] wall categories:
Generally in accordance with the wall on the hole size, number and arrangement, the
wall is divided into the following types:

Overall wall

No window and door openings, or only a few small holes, you can ignore the
existence of the hole, this wall shall be the whole wall, referred to as a whole wall.

When the window and door openings and the size of the area does not exceed 15% of
the side walls, and the clear spacing between the hole and the hole to the wall of the
hole spacing is greater than the long side dimensions, namely the whole wall.

The whole wall of small openings

Window and door openings size bigger than the whole wall, then have a partial wall
for bending moment, this wall is called a whole wall of small openings.

Coupled shear wall

Wall on the opening hole with one or more columns, and the relatively large size of
the hole, then the equivalent shear wall between the beams through the hole together a
series of wall pier, so that even the shear wall .

Shear Wall

When the underlying need for a large space, with the upper wall supporting frame
structure to form frame-supported shear wall. In the ** area, does not allow use of
pure shear wall structure supported frame.

Wall- frame

Shear wall in the Union, if the larger hole open again, making the wall weaker limb
rigidity, even when relatively strong beam stiffness, shear wall close to the framework
properties. As the thickness of shear wall frame beam width than the smaller, so that
the wall frame.

Irregular hole in the wall opening

Sometimes used as building requirements, the need to open a large wall on the hole,
and irregular arrangement of the hole shall be of such type.

Be noted that the above type of shear walls is not strictly divided, strictly define the
type of shear wall itself also need to consider the mechanical characteristics.
[Edit this section] wall structure

(A) the concept and structure of the performance of shear walls




1. Vertical load-bearing elements in buildings from the wall to bear the main, the
commitment level of both components of this wall vertical load coming from the
same time, wind or earthquake came to bear the level of earthquake. The resulting
shear wall that is named (seismic code named shear wall).

2. Is building the barrier wall and retaining wall, the wall must meet the architectural
layout of layout and structure layout requirements.

3, shear wall structure, has good carrying capacity, and there is good overall and
spatial effects, better than the frame capacity of lateral force, so the building can be
built higher.

4. Wall spacing is limited and it is not possible bay too. On the need for large space
when not applicable. Flexibility he sent. Generally applicable to residential,
apartments and hotels.

5. Wall structure of the floor structure generally use flat, you can no beam, so better
use of space can save storey.


(B) shear wall structure of the type and scope
1. Frame - shear wall structure. Is a combination of frame and shear wall structural
system, applicable to local needs large space building, when a large space in the local
part of a framework structure, but also can be used to increase shear resistance to
lateral capacity building, to meet the requirements of high-rise buildings.

2. Normal shear walls. All the shear wall structural system composed of.

3. Shear Wall Structures. When the wall structure of the bottom of the need for large
space, not all the landing wall, you need to use the box at the bottom of
frame-supported shear wall supported shear wall structure.


(C) the general structural arrangement of shear wall structure


1. Layout

Wall structure in all the vertical load and horizontal force to bear by the reinforced
concrete walls, so walls should be arranged along the plane direction of the main axis.

1) rectangle, L-shaped, T-shaped plane, the wall along the main axis of the direction
of two orthogonal layout;

2) triangular and Y-plane can be arranged along the three directions;

3) regular polygon, round and curved surface, can be arranged along the radial and
circumferential.

The length of single wall should not be too large:

1) The length of the great wall, great stiffness of the structure of the cycle will too
short, too uneconomical seismic force;

2) wall to work in a state of bending in order to have sufficient ductility, it is a high
wall should be fine, if the wall is too long, will form a low wide wall will be cut by
the damage, brittle shear wall is not conducive to seismic. Therefore, a continuous
wall on the same axis is too long, the application of the floor or even the beam is
divided into several small wall section, each wall segment of height to width ratio
should be not less than 2. Each wall section may be single wall, a small opening walls
or coupled shear walls. The width of each wall for not more than 8.0m, to ensure the
wall for control by the flexural capacity, and give full play to the role of vertical
distribution of tendons. Internal force calculations, the wall section of the floor or
between the weak beams without regard to their role, each wall were calculated as a
separate wall.
[Edit this section] wall structure characteristic
Short shear wall structure is the wall for a length of 5-8 times the thickness of the wall
structure,      commonly        used      with     "T"           shaped,
"L"               type,         "10"             Font,
"Z" shape, line type, "a" type.

This structure type is characterized by:

① combination of architecture, use of partition walls arranged vertical component
location, basically do not use the function in contradiction with the construction;

② the number of walls can be more or less, short or long leg length, mainly as the
lateral force to the needs, but also by the different size and layout to adjust the
stiffness of the center position;

③ flexible layout options for more, simple floor plan;

④ Connect the wall of the beam, with the wall for the location of the wall at intervals
within the vertical plane may be hidden;

⑤ plane under the lateral stiffness of building needs, using a central wall to form the
main lateral force resisting members, easier to meet the stiffness and strength
requirements.

On the short shear wall structural design calculations, because a wall made of large
openings, so basically the same general analysis of shear wall structure, can be used
three-dimensional bar - Department of Spatial Analysis Book pilasters or space bar -
wall-element analysis, such as the construction of the former IAS TBSA, TAT,
Guangdong Province, the mansions Architectural Design CAD-SS module, which if
built IAS TBSSAP, SATWE, Tsinghua University TUS, building homes in
Guangdong Province SSW so. The space bar wall group e lement method model is
more realistic and accurate. Although the three-dimensional bar system - Book
pilasters spatial analysis program uses an earlier application is more extensive, but the
wall for a long shear wall, should space bar - wall-element procedure for checking.

After conducting the above analysis, by "high- rise building design and
construction of" cross-section and structural design, as opposed to
special-shaped columns, short column shear theory and practice more mature, b ut this
structure is still in the structural design need to pay attention to aspects.

(1) As the short pier shear wall structure relative to its normal lateral stiffness is
relatively small, the design layout of an appropriate number of times the long wall, or
the use of elevators, stairs, forming a larger stiffness of the inner cylinder, in order to
avoid fortification intensity structures have a large deformation, but also the formation
of two earthquake-proof;

(2) short column shear seismic weak spot is the edge of the construction plane of the
wall for the corner office, when a reverse effect, it will exacerbate the existing
warping, cracking to the wall for the first, should be strengthened The seismic
structural measures, such as reducing the axial compression ratio, longitudinal
reinforcement and stirrups increased reinforcement ratio;

(3) high levels of short-pier shear walls in force, the show mainly the overall bending
deformation, the bottom of the peripheral small wall for vertical loads and to
withstand higher torsional shear, by a number of model tests reflecting the outer
peripheral wall for cracks , which should increase the external peripheral wall for
thickness and reinforcement of, the small wall for ductile seismic performance. Sho rt
shear wall should have connections in both directions to avoid the formation of
isolated "one"-shaped wall pier;

(4) of the wall for the distribution to be as even as possible, so that the stiffness center
and centroid of the building as close as possible, if necessary, to adjust the wall with a
long limb rigidity center;

(5) high- level structure with an energy beam component, in short pier shear wall
structure, wall limb rigidity decreases, the connection between the wall for the beam
have a similar general framework of the beam, and is different from the shear wall
between the beams, not in the calculation of the overall information will be greatly
reduced coupling beam stiffness, the internal force to design reduced requirements
should be common frame beam, the control concrete high pressure zone, the end of
the beam negative moment plastic reinforced by AM 70% -80% to solve, by strong
shear weak bending, strong column and weak beam ductility demands are calculated.
Calculation of shear walls
[Edit this section] the method of calculating shear wall:
Vertical shear load borne by the general structural weight and floor loading, passing
through the floor to the wall. In addition to beams of vertical load (window and door
openings on the beam) to generate moment and, in the wall for the axial force
generated within the major. Can follow the wall of a simple calculation of the loading
area.

In the horizontal loads, shear wall is actually two-dimensional plane stress analysis,
accurate calculation of the problem should be solved as a plane. With the computer
can be used to calculate the finite element method. High accuracy, but the larger
workload. In engineering design, according to different types of shear wall features to
simplify calculations.
The whole wall the whole wall and the small openings

The role of the horizontal force, the overall wall similar to a cantilever column can be
calculated in accordance with the overall cantilever bending moment and shear walls.
The whole wall of small openings, due to the impact hole, the wall stress distribution
between the limb is no longer a straight line, but the deviation is not. The whole wall
can be calculated on the basis of the corrections.

Coupled shear wall

Coupled shear wall is constrained by a series of beams form the walls of limbs can be
calculated by successive approximation method.

Wall- frame

Wall- frame can be reduced to just a domain with a framework for an improved
calculation of inflection point method.

Shear Wall and the opening hole in the wall with irregular

The two types of wall complex, preferably using the finite element method by means
of computer calculations. Determine the calculation process is to determine the
overall parameters of the calculation methods of those who pay attention and I hope
we start to discuss. There were more important and need to further understand the
concept: work with the basic principle of the principle is this: frame structure and wall
structure, two levels of structure in the deformation under load is completely different.
Framework of lateral shear curve is the curve concave to the original location; the
wall of the lateral bending curve type, curve convex to the original location. In the
frame - shear wall (hereinafter referred to as frame - shear wall) structure, since the
floor in its own plane stiffness of large frame at the same height, the lateral wall of the
same. This makes the frame - shear structure is shear horizontal displacement are not,
nor is bent type, but a bending, shear mixed, referred to as bending and shear type. In
the structure of the bottom of the frame will pull the right wall; in the top of the
structure, the framework will push the left wall. Thus, the frame - shear wall structure
at the bottom of lateral sway than the pure frame smaller than the lateral displacement
of pure shear wall structure is bigger; the top of the displacement of the opposite.
Frame and shear wall in the shared external load at the same time, deformation
compatibility between the two in order to maintain the interaction still exists.
Framework and the relationship between this interaction between shear walls shall be
collaborative works.

Consider the combination of seismic shear wall, which is carrying capacity should be
required to calculate seismic section, but in its calculation of flexural capacity of the
right side of seismic bearing capacity should be divided by the corresponding
adjustment factor γRE. Section of the wall pier shear wall considering the role of
combination of seismic design value of moment: a seismic rating of the wall and
above the bottom layer of strengthening the position, should section of the wall for the
bottom of the combination of seismic moment to consider the design value used other
parts of the combination of seismic moment can be used to consider the design value
multiplied by the magnification factor

				
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