Effect of geometrical shape

1. STUDY OF SUSTAINABLE OPTION OF
GEOMETRICALSHAPES
FOR TALL BUILDING ON LATERAL LOADS
By: Pradeep Pandya Guided by: Dr. Rajendra Kumar Shrivastava
Faculty of Civil Engineering,
SRMU, Lucknow
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2. Flow of Presentation
Introduction
Objectives
Methodology
Results
Work Plan
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3. Introduction
• A multistory building which having height
between 50 m to 250 m are known as Tall
Buildings. (described in IS 16700)
• Tall building are classifies into two categories as
per CTBUH (Council on Tall Buildings and Urban
Habitat):
• Super tall Buildings
• Mega tall Building
• In IS 16700 super tall building analysis and
design described. No any recommendation for
mega tall structures.
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4. Demand of High rise Buildings
• Scarcity of land in urban areas.
•Increasing demand for business and residential space.
•Economic growth
•Technological advancements
•Innovations in structural systems
•Concept of city skyline
•Desire for aesthetics in urban setting
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5. Objectives of the study
• To study the response of different shapes tall building.
• To study the wind pressure and seismic load in the different geometrical
shaped tall buildings.
• To compare the lateral forces induces on the different shapes building.
• To evaluate the combine effect of the earthquake and wind forces on the
different shape tall buildings with the different structural systems.
• To suggest particular plan geometry to design tall structures with heights
criteria.
• To give suggestions to IS 16700 and IS 1893 for better design practices for
dynamic and non linear analysis of tall buildings.
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6. Methodology for analysis
1. Linear Static Analysis : Equivalent Static Analysis
2. Linear Dynamic Analysis : Response Spectrum Analysis
3. Non Linear Dynamic Analysis : Time History Analysis
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7. Modelling in Software
Building Shape Plan Dimensions Plan Area
Rectangular 35m X 25m 875 m2
Triangular 45 m Each side 877 m2
Circular 33.38 m (diameter) 875 m2
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8. Specification of Buildings
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Grade of Concrete: M30
Grade of Reinforcement: HYSD Fe500
Outer columns: 900mmX900mm
Inner Columns: 600mmX600mm
Beams: 300mmX600mm
Slab: 150mm
Shear Wall : 250mm
Seismic Definition:-
Zone: IV
Importance factor: 1
Response reduction factor: 5
Site type: II (Medium)
Loads on beam: Outer Bems- 6kN/m
Inner Beams - 3kN/m
Dead load on slab: 1.5kN/m2
Live load on slab: 2kN/m2

9. Model Views
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12. Results
The building models are analyzed with the same procedure and the displacements, Storey
stiffness and drifts are compared.
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0
10
20
30
40
50
60
70
80
90
100
0 5 10 15 20 25 30 35 40 45 50
Height
(m)
Displacements (mm)
Story Deflections (X Direction)
tringular
rectangular
circular

13. The results show the story drifts of the buildings in x direction from which we can observe that
the triangular building having more drifts from 15th to 20th floor.
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0
10
20
30
40
50
60
70
80
90
100
0 0.0001 0.0002 0.0003 0.0004 0.0005 0.0006 0.0007
Height
(m)
Drifts (unitless)
STORY DRIFTS (X Direction)
Triangular
Rectangular
Circular

14. 0
10
20
30
40
50
60
70
80
90
100
0 0.0001 0.0002 0.0003 0.0004 0.0005 0.0006 0.0007
Height
(m)
Drifts (unitless)
STORY DRIFTS (Y Direction)
Triangular
Rectangular
Circular
In the drifts on y direction it is observed that
the triangular building not giving the stability
as we move toward the terrace floor the drift
values also increases.
so from this result we can say that circular
building gives minimum drifts as this building
not have re-entrant corners where the seismic
excitationn is more.
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15. Work Flow for Next Six Month
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Further
Modelling
Non-Linear
Analysis
Calculate
Scale Factor
Validation of
Results
Interpretation
of Reults

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Year&
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Activity
2021 2022 2023
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Background
Reading
Literature
Riview
Research
Planning
Data Collection
Software
Validation
Modelling in
Software
Analysis
Results and
Comparison
Conclusion
Discussion
First Draft
Final Meeting
Final Draft

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