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New Building Codes in IndiaDevelopment of
TODAY…– Status of Current Building Codes– Development of Earthquake Codes– Some New Initiatives…
3 Status of Current Building Codes
Building Codes in India
2,000National Building Code 2016
Infrequent RevisionsHarmonization of Seismic Codes initiated
Buildings
SetsPhysical Planning
DesignConcrete, Steel, Masonry, Aluminum
Soil‐Foundation SystemsMaterials
ConstructionServicesSafety
400Safety
10Earthquake
RURAL AreasSelf‐built
RURAL AreasSelf‐built
URBAN AreasContractor‐driven
Building StockRC ~ 11,000,000Clay Brick ~ 147,000,000Stone ~ 43,000,000Wood ~ 3,000,000Mud ~ 66,000,000Informal ~ 35,000,000
Total 305,000,000
• Engineers/Architects with knowledge of Earthquake Engineering ??
Census of India, 2011
Engineered ??
Non‐Engineered
320,000,000 2018
National Vision• ZERO Tolerance to avoidable deaths
Earthquake Resistant Buildings
Estimate Hazard & Analyse Structure
Design and Detail
Assess and Retrofit
Standards
New Structures
Existing Structures
IS 1893
IS 13920
IS 15988
Earthquake Safety Standards
Part Title Indian StandardIS 1893 IS 13920 IS 15988
Code of Practice Code of Practice GuidelinesCriteria for Earthquake Resistant Design of Structures
Ductile Design and Detailing of Structures subjected toSeismic Effects
Assessment and Strengthening of Existing Structures subjected toSeismic Effects
1 General Provisions and Buildings
Section A: General Provisions
Section B: Buildings
(a) Reinforced Concrete Buildings
(b) Reinforced Masonry Buildings
(c) Confined Masonry Buildings !!
(c) Structural Steel Buildings !!
Harmonisation of Indian Standards related to Structures subjected to Seismic Effects
Earthquake Safety Standards
Part Title Indian StandardIS 1893 IS 13920 IS 15988
Code of Practice Code of Practice GuidelinesCriteria for Earthquake Resistant Design of Structures
Ductile Design and Detailing of Structures subjected toSeismic Effects
Assessment and Strengthening of Existing Structures subjected toSeismic Effects
2 Liquid Retaining Tanks: Elevated & Ground Supported
3 Bridges and Retaining Walls
Section A: Bridges
Section B: Retaining Walls
Harmonisation of Indian Standards related to Structures subjected to Seismic Effects
Earthquake Safety Standards
Part Title Indian StandardIS 1893 IS 13920 IS 15988
Code of Practice Code of Practice GuidelinesCriteria for Earthquake Resistant Design of Structures
Ductile Design and Detailing of Structures subjected toSeismic Effects
Assessment and Strengthening of Existing Structures subjected toSeismic Effects
4 Industrial Structures and Stack‐like Structures
Section A: Industrial Structures
Section B: Stack‐like Structures
5 Dams and EmbankmentsSection A: Dams
Section B: Embankments
Harmonisation of Indian Standards related to Structures subjected to Seismic Effects
Earthquake Safety Standards
Part Title Indian StandardIS 1893 IS 13920 IS 15988
Code of Practice Code of Practice GuidelinesCriteria for Earthquake Resistant Design of Structures
Ductile Design and Detailing of Structures subjected toSeismic Effects
Assessment and Strengthening of Existing Structures subjected toSeismic Effects
6 Base‐Isolated Buildings !!
7 Energy Dissipation Devices 8 Non‐Structural Elements !!
9 PipelinesSection A: Buried !!
Section B: Over‐Ground !!
Harmonisation of Indian Standards related to Structures subjected to Seismic Effects
Earthquake Safety Standards
Part Title Indian StandardIS 1893 IS 13920 IS 15988
Code of Practice Code of Practice GuidelinesCriteria for Earthquake Resistant Design of Structures
Ductile Design and Detailing of Structures subjected toSeismic Effects
Assessment and Strengthening of Existing Structures subjected toSeismic Effects
9 Coastal Structures10 High Tension Lines &
Towers
Harmonisation of Indian Standards related to Structures subjected to Seismic Effects
Other Earthquake Safety Standard
S.No. Title Number1 Methodology for Seismic Microzonation in India2 …
Rapid VISUAL Screening
Conceptual VISUAL Survey
Simplified QUANTITATIVE Assessment
Detailed QUANTITATIVE Assessment
1
2
3
4
Post‐Earthquake Occupancy
Relative Degree of Damage
Overall Safety Margin
Building & Component Deficiency
4 Levels of Assessment
4 Levels of Assessment
1
3
4Rigo
ur
Time
2
23 Development of Earthquake Codes
Earthquake
An earthquake is a sudden, rapid shaking of the Earth caused by sudden release of strain energy stored in rocks.
Earthquake Shaking• Induced Effects, not Applied Force
Equivalent Force on Building
roof
Fw
Ground Movement
Earthquake Shaking• Induced Effects, not Applied Force
Zero Mean :: Cyclic
Non-zero Mean :: Oscillatory
Time
Time
Minor (Frequent) Shaking
Moderate Shaking
Severe (Infrequent) Shaking
No structural damageNo non-structural damage
Some non‐structural damage
Structural damage, but NO collapse
Objectives of EQRD
Earthquake Shaking• Induced Effects, not Applied Force
– Damage expected in normal structures•Earthquake RESISTANT Structures
– NOT Earthquake PROOF Structures
Earthquake Shaking• Induced Effects, not Applied Force
0
Lateral L
oadH
Deformation
Earthquake Behaviour:: Inelastic
Wind Behaviour:: Elastic
H
4 Virtues for Earthquake Resistance
H
Strength
Stiffness
Lateral Deformation
Late
ral L
oad
H
Ductility
Configuration
4 Generations of Building Codes
H
Strength
Stiffness
Lateral Deformation
Late
ral L
oad
H
Ductility
Configuration1
2
2
2
4Energy
3
Stiffness
H
Stiffness
Lateral Deformation
Late
ral L
oad
H
1
• Concept of Defiance1
Earthquake Design
Stiffness-Based Design
Design for Ki only
Insufficient for Earthquake-Resistant Design
Strength‐Based Design
Design for Ki and VBd
Deformation‐Based Design
Design for Ki, VBd and max
Force Design1. No srtength heirarchy2. Design of members for shear
independent of P‐M interaction
Capacity Design1. Strong‐Column Weak‐beam 2. Design of members for shear dependent of P‐M interaction
Levels of EQRD 1 2 3Mandatory for Normal buildings
in low seismic zonesNormal buildings in moderate/high seismic zones
Critical and Lifeline buildings in all seismic zones
Optional for ‐ Normal buildings in low seismic zones
Normal buildings in moderate/high seismic zones
Energy‐Based Design
Design for Ki, VBd (??), max and E
1
Indian Standards forEarthquake Resistant Design started here in 1962
Strength• Concept of Force
2AH
Lateral Deformation
Late
ral L
oad
H
Strength
2Configuration
2
Strength• Estimation of Design Force corrected in 2016
– Design Criteria fully specified•5% damping, Sa/g, Ta, m and L, Methods: Analysis/Design
– R factors – Design Vertical Acceleration Coefficient Av
– Minimum VB
– Cracked Section Properties Ieff
2A
H
Strength• Level of Design Force incorrect still
– Earthquake Hazard not represented correctly through Seismic Zone Factor Z•4 Zones
– V o.36g– IV o.24g– III o.16g– II o.10g
2A
0.36 g 0.40 g
0.35 g 0.40 g
0.36 g??
0.32 g0.11 g
0.40 g0.36 g
0.30g
0.22 g
1.0 g
1.2 g
Peak Horizontal Ground Acceleration
WAWgS
IR
ZH h
aeMCED
WAW
gS
IR
ZH h
aeMCED
Strength• Level of Design Force incorrect still
– Design Acceleration Coefficient Ah
2ACountry PGA Z/ZIndia Ah Ah/Ah, India Ah/Z
Greece 0.36 1.00 0.26 2.88 0.72
Turkey 0.40 1.11 0.13 1.44 0.33
Iran 0.35 0.97 0.14 1.56 0.40
Pakistan 0.40 1.11 0.19 2.11 0.48
India 0.36 1.00 0.09 1.00 0.25
Nepal - - 0.09 1.00 -
Indonesia 0.30 0.83 0.19 2.11 0.63
Philippines 0.40 1.11 0.11 1.22 0.28
Australia 0.22 0.61 0.15 1.66 0.68
Japan 1.00 2.78 0.30 3.33 0.30
New Zealand 1.20 3.33 0.25 2.78 0.21
Configuration• Concept ofSeismic Structural Configuration– Convex Shapes
2A
Directions of earthquake shakingConvex Form
Concave Form
Directions of earthquake shaking
Configuration• Concept ofSeismic Structural Configuration– Convex Shapes
2A
Simple Shapes Complex Shapes
Configuration•No Torsional Mode in first 3 modes
– Along each principal plan direction
Z
Y
X
2A
• Poor earthquake performance…
Configuration•URM Infill Walls
– Diagonal Strut Action
2A
Cracks
Gap
Infill walls move together with columns under earthquake shaking
Configuration•URM Infill Walls
– Strut width
where
Lds
F
F
wds
ds40
hds L1750w ..
4
cf
mh hIE4
2tEh sin
2A
Configuration•Open Ground Storey Buildings
– But, parking must within the building footprint– Mandatory to provide RC walls in such buildings
230mm230mm
2A
Configuration•Open Ground Storey Buildings
– Horizontal Storey Shear Force
Floo
r Lev
el5
4
3
2
1
Increases downwards
along height
2A
Configuration 2A
Configuration•Open Ground Storey Buildings
– Storey Strength
~ 11 : 12
2A
Configuration•Open Ground Storey Buildings
– Storey Stiffness
~ 101 : 110
2A
0
20
40
60
80
100
120
140
160
180
0 1 2 3 4 5 6
Configuration• RC Structural Wall
– Effectiveness
Structural Plan Density (%)
Mo
men
t in
In
teri
or
Co
lum
n (k
Nm
)
Wall SPD = 2%
2A
Earthquake Design
Stiffness-Based Design
Design for Ki only
Insufficient for Earthquake-Resistant Design
Strength-Based Design
Design for Ki and VBd
Deformation‐Based Design
Design for Ki, VBd and max
Force Design1. No strength hierarchy2. Design of members for shear
independent of P-M interaction
Capacity Design1. Strong‐Column Weak‐beam 2. Design of members for shear dependent of P‐M interaction
Levels of EQRD 1 2 3Mandatory for Normal buildings
in low seismic zonesNormal buildings in moderate/high seismic zones
Critical and Lifeline buildings in all seismic zones
Optional for ‐ Normal buildings in low seismic zones
Normal buildings in moderate/high seismic zones
Energy‐Based Design
Design for Ki, VBd (??), max and E
2A
53 Changes Underway
Ductility
H
Lateral Deformation
Late
ral L
oad
H
Ductility
y
y
max
max
• Concept of Ductility2B
Ductility
H
Strength
Lateral Deformation
Late
ral L
oad
H• Concept of Ductility INDIRECTLY
– Detailing
2B
2Configuration2
Ductility
2
Ductility• Design
– 2R = 10• IF = 2,R = 5
– Does the structure have a =5 (assuming it is a short period structure)?
• Verification2B
?H/Hp
0.050
0.5
1.0
0.10 0.15 0.20
1.5
/L
Ductility
(Feq)max
(Feq)max
M
V
V
M
Vc
Vc
Earthquake Design
Stiffness-Based Design
Design for Ki only
Insufficient for Earthquake-Resistant Design
Strength-Based Design
Design for Ki and VBd
Deformation‐Based Design
Design for Ki, VBd and max
Force Design1. No strength hierarchy2. Design of members for shear
independent of P-M interaction
Capacity Design1. Strong-Column Weak-beam 2. Design of members for shear
dependent of P-M interaction
Levels of EQRD 1 2 3Mandatory for Normal buildings
in low seismic zonesNormal buildings in moderate/high seismic zones
Critical and Lifeline buildings in all seismic zones
Optional for ‐ Normal buildings in low seismic zones
Normal buildings in moderate/high seismic zones
Energy‐Based Design
Design for Ki, VBd (??), max and E
2B
Deformability• Concept of Max. Lateral Deformation
3H
Lateral Deformation
Late
ral L
oad
H
Deformability
max
3
Deformability•Displacement Based Design
– How does it help?
3H
Lateral Deformation
Late
ral L
oad
H
cap maxmax
Deformability 3H
0
?
Late
ral L
oad
H
Lateral Deformation
Global Collapse Mechanism• Current Design Method
– Does NOT guarantee
Plastic Hinges
H (kN)
(mm)
125 250 375 500 625 7500
200
400
600
800
1,000
1,200
Elas
tic
Pla
stic
3
Global Collapse Mechanism•NOT predetermined
– ONLY Member Hierarchy addressed
GOOD Mechanism
POOR Mechanisms
3
Global Collapse Mechanism• Closed Loop Method of Design needed
0
H
0
H
3
Global Collapse Mechanism
Connection Rotation 0
Conn
ectio
n M
omen
t M/M
jy
Web Plates
Web Angles
Flange Angles
Flange Angles and Web Angles
Flush End Plates
Tee Stub
Extended End Plates
Top and Bottom Plates
Fully Welded
Flexible Flexible
Semi-RigidSemi-RigidRigidRigid
WeakWeak
Strong-axis ConnectionFlexibility
Relative Strength
3
Earthquake Design
Stiffness-Based Design
Design for Ki only
Insufficient for Earthquake-Resistant Design
Strength-Based Design
Design for Ki and VBd
Deformation-Based Design
Design for Ki, VBd and max
Force Design1. No strength hierarchy2. Design of members for shear
independent of P-M interaction
Capacity Design1. Strong-Column Weak-beam 2. Design of members for shear
dependent of P-M interaction
Levels of EQRD 1 2 3Mandatory for Normal buildings
in low seismic zonesNormal buildings in moderate/high seismic zones
Critical and Lifeline buildings in all seismic zones
Optional for ‐ Normal buildings in low seismic zones
Normal buildings in moderate/high seismic zones
Energy‐Based Design
Design for Ki, VBd (??), max and E
3
Energy•Ground Motions
Dynamics of StructuresA.K.Chopra
4
Energy• Input by Earthquake to Structure
4
Duration of Earthquake Shaking
Input Energy
Ener
gy
Energy• Energy absorbed WITHOUT Hysteresis
4
Duration of Earthquake Shaking
Kinetic and Strain Energy
Ener
gy
Viscous Damping Energy
Energy• Energy absorbed WITH Hysteresis
4
Duration of Earthquake Shaking
Ener
gy
Hysteretic Energy
Viscous Damping Energy
Kinetic and Strain Energy
Energy• Energy absorbed during cyclic loading
4
Bad Good
Δ Δ
H H
Energy• Cyclic behaviour
– Stable Hysteretic Response
4
Joint Distortion 0
Joint Shear V/Vy V
V
Earthquake Design
Stiffness-Based Design
Design for Ki only
Insufficient for Earthquake-Resistant Design
Strength-Based Design
Design for Ki and VBd
Deformation-Based Design
Design for Ki, VBd and max
Force Design1. No strength hierarchy2. Design of members for shear
independent of P-M interaction
Capacity Design1. Strong-Column Weak-beam 2. Design of members for shear
dependent of P-M interaction
Levels of EQRD 1 2 3Mandatory for Normal buildings
in low seismic zonesNormal buildings in moderate/high seismic zones
Critical and Lifeline buildings in all seismic zones
Optional for ‐ Normal buildings in low seismic zones
Normal buildings in moderate/high seismic zones
Energy-Based Design
Design for Ki, VBd (??), max and E
4
Seismic Design
Stiffness-Based Design
Design for Ki only
INSUFFICIENT forEarthquake-Resistant Design
Strength-Based Design
K i and VBd
Deformation-Based Design
K i, VBd and max
Force Design
(1) No hierarchy of relative strengths of members
(2) Design of members for shear independent of P-M interaction
Capacity Design
(1) Strong-Column Weak-Beam Philosophy
(2) Design of members for shear dependent of P-M interaction
Energy-Based Design
K i, VBd(??), max and E
Currently under
RESEARCHCollapse
MechanismDeformability
Energy Absorbed
Currently under
DEVELOPMENTCollapse Mechanism
Deformability
Currently IN PRACTICE
Levels of EQRD 1 2 3
Mandatory for Normal buildings in low seismic zones
Normal buildings inmoderate & high seismic zones
Critical and Lifeline buildings
Optional for - Normal buildings inlow seismic zones
Normal buildings in moderate/high seismic zones
4 Virtues for Earthquake Resistance
H
Strength
Stiffness
Lateral Deformation
Late
ral L
oad
H
Ductility
Configuration
7 Virtues of Eq. Resistant Structures
H
Strength
Stiffness
Lateral Deformation
Late
ral L
oad
H
Energy
Ductility
Configuration
Deformability
Desirable Collapse
Mechanism
1
2
34
6
5
7
78 Some New Initiatives…
The Road Ahead…•We can expect in upcoming revision of codes…– 1 step forward– 2 major changes– 3 new codes
The Road Ahead…• 1 Step Forward
– Generation 3 Earthquake Design•Displacement‐based Design
– Desirable collapse mechanism– Estimable deformation capacity
H
The Road Ahead…• 2 Major changes
– Earthquake ACCELERATION Zone Map•Probabilistic Seismic Hazard Assessment
Near‐Field Motions
S.T.G.Raghukanth
Finite Elemen
t Mod
eling
Eurasian PlateEurasian Plate
Indian PlateArabianSea
Indian Ocean
Bay ofBengal
The Road Ahead…• PSHA
– Potential events– Faults– Rock properties– Local soil properties
•YR = 5,000 years
PGA
S. T. G. Raghukanth
0.5g to 1.2g
The Road Ahead…• PSHA
– Potential events– Faults– Rock properties– Local soil properties
•YR = 10,000 years
PGA
0.7g to 1.5g
S. T. G. Raghukanth
The Road Ahead…• 2 Major changes
– Earthquake DISPLACEMENT Zone Map•First time attention drawn to Displacement
– Pipelines– High tension lines– Bridges– Tunnels
across faults
The Road Ahead…•Displacement Ground Motions
– Near‐Field Motions•Peak Ground Residual Displacement •Peak Ground Displacement
– Pulse Actions
The Road Ahead…•Near‐Field Motions
– Peak Ground Residual Displacement
The Road Ahead…•Near‐Field Motions
– Peak Ground Residual Displacement
Disp
lacemen
t (cm
)
S.T.G. Raghukanth
The Road Ahead…•Near‐Field Motions
– Peak Ground Displacement
Disp
lacemen
t (cm
)
S.T.G. Raghukanth
The Road Ahead…•Deformation Demand for each Seismic Zone
– Larger displacement demand underhigher intensity of earthquake shaking
SEVERE Shaking
MODERATE Shaking
0
H
MINOR Shaking
The Road Ahead…• 3 New Codes
– Ductile Steel Buildings– Base Isolated Buildings– Non‐Structural Elements in Buildings
In Closing …
Status
FORMPERFORMANCE
Today, focus is on…
But, what is needed is…
Performance‐Based Design •Quantify Performance
– Propose design clauses•Acceleration, Cracks, Residual Drift•Qualitative Expectations
– Immediate Occupancy, Life Safety, orCollapse Prevention
•Cost– Initial, Retrofit, or Life Cycle
RC Shear Wall
Foundation
Col
umn Beam
Slab
The Mission
Def. BD
National Disaster Management Authority, Government of IndiaBureau of Indian Standards
Professional Societies
2022
Earthquake Structural Safety Program Governments + Practitioners + Academics
2018 onwards
2025EBD
2018Duc. BD
2019
The Mission
Focus on 2 Aspects
Prevention
Mitigation
Preparedness
Response
Rehabilitation
Reconstruction
Evolve mechanisms to put in place
Systems & Processes
Earthquake Disaster Mitigation
Practice
5
4 3
1 2Typology Safety
Education
Policy
Earthquake Disaster Mitigation
Typology
Education
Safety
Practice
Policy
Typology Education Safety Practice Policy
Structural Safety Act
Risk Indexing
Peer Review
Licensing Engineers
ChangeBye Laws
Develop Standards
Undertake Retrofit
Continuing Education
Develop Skills
Full Scale Testing
New Technology
Outlaw U. Typologies
Technical Education
Manuals of G. Practice
Document Typologies
1
23 4
5
Knowledge Skills Attitude
The Critical Equation…
Competence = Attitude
+ Skills+ Knowledge
The Truth…•Many Teachers still consider EQ to be a force
– Strong capacity building campaign
•Nonlinear Analysis not taught in Colleges– Books and Teachers, before Curriculum
• Intuition missing of structural behaviour – Focus on hand‐calculations – Exaggerate deformation diagrams
The Truth…• Structural Safety is a pointed question
– Answers have to be precise•Lives are at stake
Constitution of IndiaArticle 3
Every citizen is responsible for the SAFETY of all other citizens also
Grateful • Professor Naveed Anwar
– AIT, Bangkok•Ms. Rakdao Pakdisi•Colleagues…
Clipart and Photos from InternetSome figures from
the Bureau of Indian Standards
Thank you…
Jai Hind!!