Shear walls are concrete or masonry walls that are reinforced with steel rods arranged in a grid pattern. They are designed to resist both vertical and horizontal forces like earthquakes. Shear walls are integrated throughout the building's structure to provide three-dimensional stability. Compared to framed structures, shear wall systems are more effective at withstanding earthquakes due to their larger supporting area relative to the building footprint. Properly designed and detailed shear wall buildings have demonstrated good seismic performance in past earthquakes.

1. Shear Walls
Partakers:
Faisal Saif , Ammar Shahid ,
Mohd Azhar Numani, Md
Shafaque , Shakeb Aamir
Submitted To:
U.P. Pandey Sir

2. Shear Wall
 Concrete walls, which have high plane
stiffness, placed at convenient
locations are economically used to
provide necessary resistance to
horizontal forces.
 The walls may be placed in the form of
assemblies surrounding the lift shafts
or stair wells.

3. Shear wall concept
 The walls are not only designed to resist
gravity / vertical loads (due to its self-weight
and other living / moving loads), but they
are also designed for lateral loads of
earthquakes / cyclones.
 The walls are structurally integrated with
roofs / floors and other lateral walls, thereby
giving the three dimensional stability for the
building structures.

4. Shear wall concept
 In shear wall system, it is made of concrete
or masonry wall panels, which are
reinforced, with a grid of steel rods.
 Shear wall systems are comparatively more
stable to withstand earthquakes because
their supporting area (total cross-sectional
area of all shear walls) with reference to total
plan area of building, is comparatively more,
unlike in the case of RCC framed structures.

5. Shear Walls
 Reinforced concrete (RC) buildings have
vertical plate-like RC walls called Shear Walls
in addition to columns, beams and slabs.
 These walls generally start at foundation level
and are continuous throughout the building
height.
 Their thickness can be as low as 150mm, or as
high as 400mm in high rise buildings.
 Shear walls are usually provided along both
length and width of buildings.
 Shear walls are like vertically-oriented wide
beams that carry earthquake loads downwards
to the foundation.

7. Shear Walls
 Properly designed and detailed buildings with
shear walls have shown very good
performance in past earthquakes.
 A noted consulting engineer in USA, Mark
Fintel’s quote:
“We cannot afford to build concrete buildings
meant to resist severe earthquakes without
shear walls.”

8.  Shear walls in high seismic regions require special
detailing.
 However, even buildings with sufficient amount of
walls that were not specially detailed for seismic
performance (but had enough well-distributed
reinforcement) were saved from collapse.
 Shear walls are easy to construct, because
reinforcement detailing of walls is relatively straight-
forward and therefore easily implemented at site.
 Shear walls are efficient, both in terms of
construction cost and effectiveness in minimizing
earthquake damage in structural and non-structural
elements (like glass windows and building contents).
 Shear wall buildings are a popular choice in many
earthquake prone countries, like Chile, New Zealand
and USA.

10. Ductile Design of Shear Walls
 Like reinforced concrete (RC) beams and
columns, RC shear walls also perform much
better if designed to be ductile.
 Overall geometric proportions of the wall,
types and amount of reinforcement, and
connection with remaining elements in the
building help in improving the ductility of walls.
 The Indian Standard Ductile Detailing Code
for RC members (IS:13920-1993) provides
special design guidelines for ductile detailing
of shear walls.

11. Overall Geometry of Walls
 Overall Geometry of Walls: Shear
walls are oblong in cross-section, i.e.,
one dimension of the cross-section is
much larger than the other.
 While rectangular cross-section is
common, L- and U-shaped sections are
also used.
 Thin-walled hollow RC shafts around the
elevator core of buildings also act as
shear walls, and should be taken
advantage of to resist earthquake forces.

13. Reinforcement
 Steel reinforcing bars are to be provided in
walls in regularly spaced vertical and
horizontal grids .
 The vertical and horizontal reinforcement in
the wall can be placed in one or two parallel
layers called curtains.
 Horizontal reinforcement needs to be
anchored at the ends of walls.
 The minimum area of reinforcing steel to be
provided is 0.0025 times the cross-sectional
area.
 This vertical reinforcement should be
distributed uniformly across the wall cross-
section.

15. Shear wall construction
 Unlike RCC framed structures, which are
to be built of columns, beams and slabs,
the shear walls are to be ideally built of
RCC walls and slabs.
 Though constructing RCC slabs are
conventional, casting RCC walls are not.
 RCC walls are relatively quite costlier and
it requires a special system of formwork,
calling for more investment.

16. RHCBM technique
 Reinforced Hollow Concrete Block
Masonry (RHCBM) construction
technique is an optimal solution, both
from the angles of cost effectiveness
and structural safety.
 RHCBM walls are constructed by
reinforcing the hollow concrete block
masonry, by taking advantage of hollow
spaces and shapes of the hollow
blocks.

17. RHCBM technique
 It requires continuous steel rods
(reinforcement) both in the vertical and
horizontal directions at structurally critical
locations of the wall panels, packed with the
fresh grout concrete in the hollow spaces of
masonry blocks.
 In many parts of USA and other seismically
prone countries of the world, this
construction technique is popularly being
utilised.

18. Guidelines for the design
 It is advisable to provide minimum 12mm rod
in every corner of a wall panel and at every
free end of the wall panel.
 At a spacing of maximum 1.2m, minimum
one rod of 8mm is to be provided.
 Similarly reinforcement is to be provided all
around any openings such as windows and
doors.

19. Guidelines for the design
 Horizontal reinforcement is to be provided at
floor level, sill (window bottom) level, lintel
(window top) level, and roof levels in each
storey.
 In moderate earthquake zones it may be
sufficient to grout only the hollow spaces
where reinforcement is being provided.
 However in severe earthquake zones it is
advisable to grout all the hollow spaces in the
entire wall panels and increase the quantity of
reinforcement provision.

20. Shear wall construction -
Barker Hall Project, University of California

21. Structural Systems