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					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.
  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:
¢Ù combination of architecture, use of partition walls arranged
vertical component location, basically do not use the function in
contradiction with the construction;
¢Ú 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;
¢Û flexible layout options for more, simple floor plan;
¢Ü Connect the wall of the beam, with the wall for the location of the
wall at intervals within the vertical plane may be hidden;
¢Ý 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 elemen
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, but 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.
Short 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
wall
[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 ¦ÃRE.
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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posted:8/30/2010
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