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STATIC AND DYNAMIC ANALYSIS OF A MULTI- STORIED BUILDING · In this project a multi-storied...
Transcript of STATIC AND DYNAMIC ANALYSIS OF A MULTI- STORIED BUILDING · In this project a multi-storied...
K RAMYA K , et al , International Journal of Research Sciences and Advanced Engineering [IJRSAE]TM
Volume 2 , Issue 8, PP: 193 - 207 , OCT - DEC 2014.
193 – 207
International Journal of Research Sciences and Advanced Engineering
Vol.2 (8) , ISSN: 2319 – 6106 , OCT - DEC – 2014.
STATIC AND DYNAMIC ANALYSIS OF A MULTI-
STORIED BUILDING
K RAMYA KRISHNA 1*, CH SURENDRA REDDY 2*
1. II.M.Tech , Dept of CIVIL ENGG, JOGAIAH INSTITUTE OF TECHNOLOGY &
SCIENCES , PALAKOL , AP .
2. Asst .Prof, Dept of CIVIL ENGG, JOGAIAH INSTITUTE OF TECHNOLOGY &
SCIENCES, PALAKOL, AP.
ABSTRACT:
Multi-storied buildings are supposed to be of engineered construction in the sense
that they might have been analyzed and designed to meet the provisions of the relevant
codes of practice and building bye-laws; the construction might have been supervised by
trained persons. In such cases, even if earthquake forces have not been considered
precisely, the structures would have adequate in-built strength and ductility to withstand
some level of earthquake intensity. In this project a multi-storied building of three storey
that is G+3 building is designed for the maximum lateral forces with the help of equivalent
static analysis which is mentioned in IS: 1893-2002, part 1.
The major steps involved in construction of a structure apart from analysis and
design are site selection, survey of the site, orientation of the building. Selection of site
plays a major role in any construction. The factors effecting site selection are topography,
nature of soil, position of ground water table, facilities, neighborhood, vegetation, shape
of the site. Surveying includes preliminary survey and quadratic survey. Levelling of the
site is also done in surveying. Orientation of a building is the proper placement of the
building and its component rooms with respect to the weathering elements. Three
parameters which govern the orientation of the building are temperature, wind and
humidity.
. Moment Resisting Frames rely on the ability of the frame itself to act as a
partially or fully rigid jointed frame while resisting the lateral loads. Due to their flexibility,
moment resisting frames can be used for medium rise buildings having up to ten stories.
Ordinary moment resisting frames doesn't meet special detailing requirements for ductile
detailing.
K RAMYA K , et al , International Journal of Research Sciences and Advanced Engineering [IJRSAE]TM
Volume 2 , Issue 8, PP: 193 - 207 , OCT - DEC 2014.
193 – 207
International Journal of Research Sciences and Advanced Engineering
Vol.2 (8) , ISSN: 2319 – 6106 , OCT - DEC – 2014.
1 . SOFTWARE:
Structural Analysis Program
usually known as SAP is a very powerful
and practical tool for structural design.
SAP2000 Version 14.0.0 follows in the
same tradition featuring a very
sophisticated, intuitive and versatile user
interface powered by an unmatched
analysis engine and design tools for
engineers. SAP2000 is a full-featured
program that can be used for the simplest
problems and it can also be used for or
most complex projects.SAP has many
features comprising of non-linear and
pushover analysis, dynamic analysis,
bridge modelling and design. Apart from
this SAP2000 Version 14.0.0 has many
other features.
From its 3D object based
graphical modelling environment to the
wide variety of analysis and design
options. SAP2000 represents the most
sophisticated and user friendly release all
other computer programs. Creation and
modification of the model, execution of
the analysis, checking and optimization of
the design and production of the output
are all done under a single interface. A
single structural model can be used for a
wide variety of different types of analysis
and design. SAP2000 can be used for all
of our analysis and design tasks. In SAP
2000, Complex Models can be generated
and meshed with powerful Templates
built into the interface which is the major
advantage of this package. Bridge
Designers can use SAP2000 Bridge
Templates for generating Bridge Models,
Automated Bridge Live Load Analysis and
Design, Bridge Base Isolation, Bridge
Construction Sequence Analysis, Large
Deformation Cable Supported Bridge
Analysis and Pushover Analysis. From a
simple small 2D static frame analysis to a
large complex 3D nonlinear dynamic
analysis, SAP2000 is the answer to all
structural analysis and design needs.
Advantages of SAP:
1. It allows easier global integration.
2. It provides real time information.
3. It reduces the possibility of
redundancy errors.
4. It provides a good knowledge like an
expert about building and
implementation of a system.
Disadvantages:
K RAMYA K , et al , International Journal of Research Sciences and Advanced Engineering [IJRSAE]TM
Volume 2 , Issue 8, PP: 193 - 207 , OCT - DEC 2014.
193 – 207
International Journal of Research Sciences and Advanced Engineering
Vol.2 (8) , ISSN: 2319 – 6106 , OCT - DEC – 2014.
1. To implement and use SAP can
be very expensive.
2. CODE BOOKS
Code books play a major role in the
analysis and design of any structure. A
building has to perform many functions
satisfactorily. Amongst these functions
are the utility of the building for the
intended use and occupancy, structural
safety, fire safety and compliance with
hygienic, sanitation, ventilation and
daylight standards. The design of the
building is dependent upon the minimum
requirements prescribed for each of the
above functions. The minimum
requirements pertaining to the structural
safety of the buildings are being covered
in different codes. Code books are
referred to reduce the hazards to life and
property caused by unsafe structures, but
also eliminates the wastage caused by
assuming unnecessarily heavy loadings
without proper assessment.
The code books referred for this project
are:
● IS 456:2000 (reinforced concrete for
general building construction)
● IS 875, part 1, 1987(dead loads for
building and structures)
● IS 875, part 2, 1987(imposed loads for
buildings and structures)
● IS 875, part 3, 1987(wind loads for
buildings and structures)
● IS 875, part 4, 1987(design loads for
buildings and structures)
● IS 875, part 5(special loads and
combinations for buildings and
structures)
● SP 16 (design aids for IS 456)
● SP24 (explanatory handbook for IS
456)
● SP34 (handbook on reinforcement and
detailing)
● IS 1893, part 1(A seismic Design Of
Multi-storied Reinforced Concrete
buildings)
● Proposed Draft Provisions and
Commentary on Indian seismic Code IS
1893, part 1, 2002
● Review of Geotechnical Provisions in
Indian Seismic Code IS 1893, part 1:
2002
● Explanatory Examples on Indian
Seismic Code IS 1893, part 1
3. DETAILS OF THE STRUCTURE
Prior to the planning of a residential
building, it is essential for the planner to
consider the following:
1. Size, shape and location of the plot
K RAMYA K , et al , International Journal of Research Sciences and Advanced Engineering [IJRSAE]TM
Volume 2 , Issue 8, PP: 193 - 207 , OCT - DEC 2014.
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International Journal of Research Sciences and Advanced Engineering
Vol.2 (8) , ISSN: 2319 – 6106 , OCT - DEC – 2014.
2. Specific requirements of the occupants
3. Fund resources available
4. Locally available materials for
construction.
5. Meteorological conditions of the area
The units which are must for a
residential building are the bedroom,
kitchen, dining hall, w.c and bath and a
stair if more than one storey is needed.
In addition to these, other units like guest
room, drawing room, store room,
verandah etc. All the rooms in a structure
are having a main function to provide
proper ventilation for all the units. The
orientation of the rooms, doors and
windows are placed such that there is
proper ventilation in the building. The
rooms should be comfortable and
spacious. The rooms should get adequate
natural light and breeze. Especially in
kitchen, much illumination provides
safety, clarity, cheerfulness and prevents
fatigue. Hence natural and artificial
illumination is must for any building.
3.1 ELEVATION:
Elevation is a graphical representation, to
some scale, of the features on, near or
below the surface of the earth is projected
on a vertical plane which is represented
by plane of the paper on which elevation
is drawn. Simply, elevation is the front
view of the structure.
Figure 1.1 Elevation of the structure
3.2 PLAN AND ELEVATION OF THE
STRUCTURE:
A plan is a graphical
representation, to some scale, of the
features on, near or below the surface of
the earth is projected on a horizontal
plane which is represented by plane of
the paper on which plan is drawn. Simply,
a plan is the top view of the structure.
K RAMYA K , et al , International Journal of Research Sciences and Advanced Engineering [IJRSAE]TM
Volume 2 , Issue 8, PP: 193 - 207 , OCT - DEC 2014.
193 – 207
International Journal of Research Sciences and Advanced Engineering
Vol.2 (8) , ISSN: 2319 – 6106 , OCT - DEC – 2014.
Figure Plan of the structure
4. GRAVITY LOAD ANALYSIS:
A shear force diagram can be
constructed from the loading diagram of
the beam. In order to draw this, first the
reactions must be determined always.
Then the vertical components of forces
and reactions are successively summed
from the left end of the beam to preserve
the mathematical sign conventions
adopted. The shear at a section is simply
equal to the sum of all the vertical forces
to the left of the section.
When the successive
summation process is used, the shear
force diagram should end up with the
previously calculated shear (reaction at
right end of the beam. No shear force acts
through the beam just beyond the last
vertical force or reaction. If the shear
force diagram closes in this fashion, then
it gives an important check on
mathematical calculations.
The bending moment diagram is
obtained by proceeding continuously
along the length of beam from the left
hand end and summing up the areas of
shear force diagrams giving due regard to
sign. The process of obtaining the
moment diagram from the shear force
diagram by summation is exactly the
same as that for drawing shear force
diagram from load diagram.
GRAVITY LOADS FROM SAP
Figure Bending moment diagram for
gravity loads from SAP.
W
N
E
S
K RAMYA K , et al , International Journal of Research Sciences and Advanced Engineering [IJRSAE]TM
Volume 2 , Issue 8, PP: 193 - 207 , OCT - DEC 2014.
193 – 207
International Journal of Research Sciences and Advanced Engineering
Vol.2 (8) , ISSN: 2319 – 6106 , OCT - DEC – 2014.
GRAVITY LOADS FROM SAP
Figure: Shear force diagram for
gravity loads from SAP.
The complete details of the
residential building have been explained
in this chapter. Location of beams and
columns, grid line marking are clearly
explained. Only gravity loads are taken
into consideration and analysis is done
manually and using a package SAP2000.
Manual analysis comprises of load
distribution of slabs on to beams and
calculation of bending moment and shear
force values by any approximate method.
The steps for analysis by SAP are also
explained in this chapter. The lateral load
analysis is carried out in further chapters
and compared with that of gravity load
analysis.
5. EQUIVALENT STATIC
ANALYSIS:
The objective of seismic analysis is
to access the force and deformation
demands and capacities on the structural
system and its individual components.
ESA can be used to estimate the
displacement demands for structures
where a more sophisticated dynamic
analysis will not be provide additional
insight into behaviour.
When loads are applied to a body,
the body deforms and the effect of loads
is transmitted throughout the body. The
external loads induce internal forces and
reactions to render the body into a state
of equilibrium. For analysing such bodies’
static analysis is used.
ESA determines the displacement,
and forces in a structure or components
caused by the loads that do not induce
significant inertia and damping effects.
ESA can be used to calculate the
structural response of bodies spinning
with constant velocities or travelling with
K RAMYA K , et al , International Journal of Research Sciences and Advanced Engineering [IJRSAE]TM
Volume 2 , Issue 8, PP: 193 - 207 , OCT - DEC 2014.
193 – 207
International Journal of Research Sciences and Advanced Engineering
Vol.2 (8) , ISSN: 2319 – 6106 , OCT - DEC – 2014.
constant accelerations since the
generated loads do not change with time.
Steady loading and response conditions
are assumed in ESA. That is the loads and
the structures response are assumed to
vary slowly with respect to time.
Earthquakes are occasional forces
on structures that may occur rarely
during the lifetime of buildings. It is also
likely that a structure may not be
subjected to severe earthquake forces
during its design lifetime. Even if
earthquake forces have not been
considered precisely, the structures
would have adequate in-built strength
and ductility to withstand some level of
earthquake intensity. The main factors
that should be taken into consideration in
constructing a building with earthquake
forces are as follows:
Zone factor (Z): The varying geology at
different locations in the country implies
that the likelihood of damaging
earthquakes taking place at different
locations is different. Based on the levels
of intensities sustained during damaging
past earthquakes, the 1970 version of
zone map subdivided India into five zones
- I, II, III, IV and V. The Indian Standards
provided the first seismic zone map in
1964, which was later revised in 1967,
again in 1970 and again in 2002. Now it
has only four seismic zones - II, III, IV
and V. The zone factors for different
zones.
Table: Zone factors
Zone II III IV V
Zone factor(Z) 0.1 0.16 0.24 0.36
Soil type: Soils are of different types
namely, soft, medium and hard soils.
Recorded earthquake motions show that
the response spectrum shape varies with
the soil profile at the site. The variation in
ground motion characteristics for
different sites is accounted for by
providing different shapes of response
spectrum for each of the sites.
Importance factor (I): Seismic design
philosophy assumes that a structure may
undergo some damage during severe
shaking. However, critical and important
facilities must respond better in a
earthquake than an ordinary structure.
Importance factor is used to obtain the
design seismic force depending on the
functional use of the structure,
characterized by hazardous
consequences of the risk resulting from
K RAMYA K , et al , International Journal of Research Sciences and Advanced Engineering [IJRSAE]TM
Volume 2 , Issue 8, PP: 193 - 207 , OCT - DEC 2014.
193 – 207
International Journal of Research Sciences and Advanced Engineering
Vol.2 (8) , ISSN: 2319 – 6106 , OCT - DEC – 2014.
its failure. Here, the risk is associated
with hazardous consequences of the
failure of the structure, its post-
earthquake functional need, historic
value and economic importance.
Response reduction factor (R): The
structure is allowed to be damaged in
severe shaking. Hence, structure is
designed for seismic force much less than
what is expected under strong shaking if
the structure were to remain linearly
elastic. A building is expected to undergo
damage in case of strong shaking and
therefore should be detailed for ductility.
Response reduction factor is the factor by
which elastic responses of the structure,
such as base shear and element forces,
generated under the action of earthquake
shaking as specified in IS1893:2002 are
reduced to obtain the design values of the
responses.
6. CALCULATION OF FRAME
LOAD FOR EACH STOREY:
For the calculation of frame loads,
stiffness of each and every frame is
required. In this project the stiffness
values are directly taken from the
software SAP which is used in the design
of the structure.
The stiffness, k, of a body is a measure
of the resistance offered by an elastic
body to deformation. The stiffness is
defined as
k = P/δ
where P is the force applied on the body
and
δ is the displacement produced by the
force along the same degree of freedom
When a graph is plotted between load
applied in X-direction and displacement in
Y-direction, stiffness obtained is linear as
shown in the graph below.
Figure 2.3
Graph for stiffness calculation
The figure 2.3 is taken from a journal
with title "Seismic Strengthening of RC
Frame buildings: The Formal
Quantitative Approach" by C. V. R.
Murty.
K RAMYA K , et al , International Journal of Research Sciences and Advanced Engineering [IJRSAE]TM
Volume 2 , Issue 8, PP: 193 - 207 , OCT - DEC 2014.
193 – 207
International Journal of Research Sciences and Advanced Engineering
Vol.2 (8) , ISSN: 2319 – 6106 , OCT - DEC – 2014.
When a load of 1kN is applied on the top
storey of the frame in lateral direction at
one end, the frame tends to possess a
displacement or deformation at the other
end for the applied load as shown in the
figure below. Then the load per
displacement value gives the stiffness of
that frame which is calculated below. The
displacement of the frame 1 is shown in
figure below.
7. DESCRIPTION:
Torsion is the twisting of an object due to
an applied torque. When the centre of
mass and centre of stiffness of a structure
doesn't coincide, it results in some
eccentricity in one or both directions. This
eccentricity further results in torsion
forces. As per IS 1893:2002 Part1, the
formula for calculating torsion is given by
T = 2
idiii R/xexFxRKi
Where, T = torsion force;
Ki = stiffness of each frame in
both X and Y directions;
Ri = radius of gyration from the
centre of stiffness;
Fi = load on each frame in both X
and Y directions
For calculating the values of torsion for
each frame, firstly centre of mass and
centre of stiffness are to be calculated.
Then eccentricities in both X and Y
directions are calculated as done in 3.3.
7.1 ANALYSIS OF A FRAME:
Building frames are most common
structural form which is in practice.
Usually the building frames are designed
such that the beam column joints are
rigid. Analysis of frames is carried out by
considering planar frame in two
perpendicular directions separately for
both vertical and horizontal loads and
finally superimposing moments
approximately. In this case of building
frames, the beam column joints are
monolithic and can resist bending
moment, shear force and axial force. The
methods available for analysing vertical
loads on frames are
1. Slope deflection method
2. Stiffness method
3. Substitute frame method
In this chapter, we are doing analysis
only for lateral loads. A building frame
may be subjected to wind and earthquake
loads during its life time. Thus, the
K RAMYA K , et al , International Journal of Research Sciences and Advanced Engineering [IJRSAE]TM
Volume 2 , Issue 8, PP: 193 - 207 , OCT - DEC 2014.
193 – 207
International Journal of Research Sciences and Advanced Engineering
Vol.2 (8) , ISSN: 2319 – 6106 , OCT - DEC – 2014.
building frames must be designed to
withstand lateral loads. Analysis of
frames for lateral loads can be done using
different methods mentioned below.
1. Moment Distribution Method
2. Cantilever Method
3. Portal Frame Method
The above mentioned methods are
approximate methods. In this project we
are using portal frame method to analyse
the lateral loads of a frame.
8. LIMIT STATE METHOD:
Working stress method gives satisfactory
performance of the structure at working
loads; it is unrealistic at ultimate state of
collapse. Similarly, the ultimate load
method provides realistic assessment of
safety but doesn't guarantee the
satisfactory serviceability requirements
at service loads. An ideal method is the
one which takes into account not only the
ultimate strength of the structure but also
the serviceability and durability
requirements. The newly emerging limit
state method of design is oriented
towards the simultaneous satisfaction of
all these requirements. In this method, a
structure is designed against safety of
collapse and checked for its serviceability
at working loads, thus rendering the
structure fit for its intended use, thus
limit state method includes consideration
of a structure at both the working and the
ultimate load levels with a view to satisfy
the requirements of safety and
serviceability.
8.1 Types of limit state:
Limit state is a state of impending failure
beyond which a structure tends to
perform its intended function
satisfactorily, in terms of safety and
serviceability. The acceptable limit for the
safety and serviceability requirements
before failure occurs is called a limit state.
Two categories of limit state are
considered in the design.
i. Limit state of collapse
ii. Limit state of serviceability
9 . DESIGN OF STRUCTURE:
The design of structure is done according
to limit state method for compression
members, beams, slabs and footings.
9.1 DESIGN OF SLAB
A Reinforced Concrete Slab is the
one of the most important component in
a building. It is a structural element of
modern buildings. Slabs are supported
on Columns and Beams. RCC Slabs
K RAMYA K , et al , International Journal of Research Sciences and Advanced Engineering [IJRSAE]TM
Volume 2 , Issue 8, PP: 193 - 207 , OCT - DEC 2014.
193 – 207
International Journal of Research Sciences and Advanced Engineering
Vol.2 (8) , ISSN: 2319 – 6106 , OCT - DEC – 2014.
whose thickness ranges from 10 to 50
centimetres are most often used for the
construction of floors and ceilings. Thin
concrete slabs are also used for exterior
paving purpose. In many domestic and
industrial buildings a thick concrete slab,
supported on foundations or directly on
the sub soil, is used to construct the
ground floor of a building. In high rises
buildings and skyscrapers, thinner, pre-
cast concrete slabs are slung between the
steel frames to form the floors and
ceilings on each level.
9.2 DESIGN OF EXTERIOR BEAM
RCC beams are cast in cement
concrete reinforced with steel bars.
Beams take up compressive and add
rigidity to the structure. Beams generally
carry vertical gravitational forces but can
also be used to carry horizontal loads.
The loads carried by a beam are
transferred to columns, walls, or girders,
which then transfer the force to adjacent
structural compression members.
In Lightframe construction the joists rest
on the beam.
RCC beam construction is of two
types:
Singly reinforced beam
Doubly reinforced beam
Singly reinforced beam
A singly reinforced beam is a beam
provided with longitudinal reinforcement
in the tension zone only.
Doubly reinforced beam
Beams reinforced with
steel in compression and tension zones
are called doubly reinforced beams. This
type of beam will be found necessary
when due to head room consideration or
architectural consideration the depth of
the beam is restricted. The beam with its
limited depth, if reinforced on the tension
side only, may not have enough moment
of resistance, to resist the bending
moment. By increasing the quantity of
steel in the tension zone, the moment of
resistance cannot be increased
indefinitely. Usually, the moment of
resistance can be increased by not more
than 25% over the balanced moment of
resistance, by making the beam over-
reinforced on the tension side. Hence, in
order to further increase the moment of
resistance of a beam section of unlimited
dimensions, a doubly reinforced beam is
provided.
9.2 FOOTING:
K RAMYA K , et al , International Journal of Research Sciences and Advanced Engineering [IJRSAE]TM
Volume 2 , Issue 8, PP: 193 - 207 , OCT - DEC 2014.
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Vol.2 (8) , ISSN: 2319 – 6106 , OCT - DEC – 2014.
Foundation is the base of any structure.
Without a firm foundation, the structure
cannot stand. That is the reason why we
have to be very cautious with the design
of foundations because our entire
structure rests on the foundation. The
strength of the foundation determines the
life of the structure. Design of foundation
depends on the type of soil, type of
structure and its load. On that basis, the
foundations are basically divided into
Shallow Foundations and Deep
Foundations.
Reinforced Concrete Footings
Footing comprises of the lower end of a
column, pillar or wall which is enlarged
with projecting courses so as to distribute
load. Footings shall be designed to
sustain the applied loads, moments and
forces and the induced reactions and to
ensure that any settlement which may
occur shall be as uniform as possible and
the safe bearing capacity of soil is not
exceeded. In sloped or stepped footings,
the effective cross-section in compression
shall be limited by the area above the
neutral plane, and the angle of slope or
depth and location of steps should be
such that the design requirements are
satisfied at every section
9.3 DESIGN OF STAIRCASE
Stairs consist of steps arranged in a
series for purpose of giving access to
different floors of a building. Since a stair
is often the only means of communication
between the various floors of a building,
the location of the stair requires good and
careful consideration. In a residential
house, the staircase may be provided
near the main entrance. In a public
building, the stairs must be from the main
entrance itself and located centrally, to
provide quick accessibility to the principal
apartments. All staircases should be
adequately lighted and properly
ventilated.
Various types of Staircases
Straight stairs
Dog-legged stairs
Open newel stair
Geometrical stair
RCC design of a Dog-legged staircase
In this type of staircase, the
succeeding flights rise in opposite
directions. The two flights in plan are not
separated by a well. A landing is provided
corresponding to the level at which the
direction of the flight changes.
Reinforcement Detailing:
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Volume 2 , Issue 8, PP: 193 - 207 , OCT - DEC 2014.
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Vol.2 (8) , ISSN: 2319 – 6106 , OCT - DEC – 2014.
18-8mmØbars@240mm c-c
24-
12mmØbars@175mm c-c
Figure
Reinforcement detailing of staircase
9. TIME HISTORY ANALYSIS
The modal analysis procedure to
determine the response of a structure to
earthquake induced motion, identical at
all support points of the structure is Time
History Analysis (THA). Response of the
structure can be calculated using
numerical methods (Central Difference
Method, Newmarks Method).
Finding the response of the Multi Degree
Of Freedom structure:
The equation of motion is
[ M ] [ Ü ] + [ C ] [U] +[ K ] [ U ] = -
[ M ] [ Üg ] [ 1 ] (1)
qi(t)+ 2𝛏i 𝛚i qi +𝛚i2 qi(t) = piÜg
(2)
By using numerical methods calculate the
response of the structure with any
number of storeys. By multiplying the
corresponding Eigen vectors we will get
the final response of the structure.
Generally, the first mode of
vibration is one of the primary interests.
The first mode usually has the largest
contribution to the structure’s motion.
Actually infinite numbers of modes are
existing within a building, but these are
less during an earthquake.
The significance of a mode is
indicated by mass participation. This
factor indicates the amount of the total
structural mass that is activated by a
single mode. If all modes of a structure
are considered, the cumulative mass
participation will be 100%. Structures
K RAMYA K , et al , International Journal of Research Sciences and Advanced Engineering [IJRSAE]TM
Volume 2 , Issue 8, PP: 193 - 207 , OCT - DEC 2014.
193 – 207
International Journal of Research Sciences and Advanced Engineering
Vol.2 (8) , ISSN: 2319 – 6106 , OCT - DEC – 2014.
with 80% of the mass in the first mode
will be dominated by the mode shape
only.
Time History Analysis is done in
SAP to get the analysis values and
compare it with static analysis.
10. CONCLUSIONS
The complete details of the
residential building have been explained
in chapter 1. Location of beams and
columns, grid line marking are clearly
explained. Only gravity loads are taken
into consideration and analysis is done
manually and using a package SAP2000.
Manual analysis comprises of load
distribution of slabs on to beams and
calculation of bending moment and shear
force values by any approximate method.
The lateral load analysis is carried out and
compared with that of gravity load
analysis.
In addition to gravity loads,
lateral loads are calculated in this chapter
as per the procedure in IS: 1893-2002;
Equivalent Static Analysis (ESA). Many
factors, such as seismic weight of the
structure, zone factor, importance factor,
response reduction factor, have a great
influence on the structure. Hence all
these factors are taken into consideration
for the calculation of lateral loads. With
the above mentioned factors, the design
base shear is calculated. Later this base
shear is distributed to each floor and then
to each frame of the structure.
Lateral loads, torsion forces also
act on the structure if the structure is not
symmetric. The structure clearly is not
symmetric, that is the centre of mass and
centre of stiffness doesn't coincide. Hence
there is eccentricity in Y-direction.
Therefore torque is developed in the
structure. Due to this torque torsion
forces are developed. As the eccentricity
produced is minimum, the torsion forces
are also minimum. When analysis is done
for any building including torsion, the
bending moment values were almost
similar to that of bending moment values
obtained only for lateral loads. Hence
these torsion forces are negligible and the
design of frame section is done only for
lateral loads.
The last chapter deals with
dynamic analysis. Time History Analysis
is a type of dynamic analysis where
ground motion is required without
applying any lateral loads. Time History
Analysis has been done only in SAP2000
K RAMYA K , et al , International Journal of Research Sciences and Advanced Engineering [IJRSAE]TM
Volume 2 , Issue 8, PP: 193 - 207 , OCT - DEC 2014.
193 – 207
International Journal of Research Sciences and Advanced Engineering
Vol.2 (8) , ISSN: 2319 – 6106 , OCT - DEC – 2014.
to check the analysis values with that
obtained from static analysis and to check
the response history that is acceleration,
velocity, and displacement etc of every
node in the structure. Response history
for different ground motions (Uttarkasi,
Chamoli, Bhuj) is done in this chapter.
11. BIBILIOGRAPHY
i) Illustrated Design of Reinforced
Concrete Buildings by Dr. S. R. Karve and
Dr. V. L. Shah
ii) Strength of Materials by S.
Ramamrutham.
iii) Design of Reinforced Concrete
Structures by A. K. Jain
iv) Structural Analysis by V. N. Vazirani,
M. M. Ratwani and S. K. Duggal
v) The code books referred for this
project are:
● IS 456:2000 (reinforced concrete for
general building construction)
● IS 875, part 1, 1987(dead loads for
building and structures)
● IS 875, part 2, 1987(imposed loads
for buildings and structures)
● IS 875, part 3, 1987(wind loads for
buildings and structures)
● IS 875, part 4, 1987(design loads for
buildings and structures)
● IS 875, part 5(special loads and
combinations for buildings and
structures)
● SP 16 (design aids for IS 456)
● SP24 (explanatory handbook for IS
456)
● SP34 (handbook on reinforcement and
detailing)
● IS 1893,part 1(Aseismic Design Of
Multi-storied Reinforced Concrete
buildings)
● Proposed Draft Provisions And
Commentary On Indian seismic Code IS
1893, part 1, 2002
● Review Of Geotechnical Provisions In
Indian Seismic Code IS 1893, part 1 :
2002
● Explanatory Examples On Indian
Seismic Code IS 1893, part 1