INTRODUCTION TO
SEISMIC DESIGN IN
ACCORDANCE WITH MS
EN 1998
28 OGOS 2020
Presented by :
Ir. LEE CHOON SIANG
Jurutera Awam Penguasa
Cawangan Kejuruteraan Awam dan Struktur
Tingkat 1u, Block G
Ibu Pejabat JKR, Jalan Sultan Salahuddin, 50480 Kuala Lumpur.
Email: cslee.jkr@1govuc.gov.my
Civil Works & Structural Engineering Branch
Jabatan Kerja Raya Malaysia, Kuala Lumpur
Plate Boundaries
Civil Works & Structural Engineering Branch
Jabatan Kerja Raya Malaysia, Kuala Lumpur
Taiwan Plate Boundaries
Civil Works & Structural Engineering Branch
Jabatan Kerja Raya Malaysia, Kuala Lumpur
Surface Body Waves
• Primary wave (P-Wave)
− 1st arrival
− High velocity
− Know as Compression wave
• Secondary Wave (S-Wave)
− Arrive after P-wave
− Having 60% of P-wave velocity
− Recorded in both Vertical and
horizontal directions
In the case of local or nearby
earthquakes, the difference in the
arrival times of the P and S waves can
be used to determine the distance to
the event.
S- Wave in action
Civil Works & Structural Engineering Branch
Jabatan Kerja Raya Malaysia, Kuala Lumpur
Questions
How do we measure earthquake?
By Richter scale?
What is the engineering
measurement units for earthquake?
Civil Works & Structural Engineering Branch
Jabatan Kerja Raya Malaysia, Kuala Lumpur
Intensity:
The severity of earthquake shaking is assessed using
a descriptive scale. – The Modified Mercalli Intensity Scale.
Civil Works & Structural Engineering Branch
Jabatan Kerja Raya Malaysia, Kuala Lumpur
Unit Measurements:
Earthquake size is a quantitative measure of the size of
the earthquake at its source.-The Richter Magnitude
Scale.
Acceleration Velocity
Richter Sacle Perceived shaking Potential damage
(g) (cm/s)
I < 0.0017 < 0.1 Not felt None
II–III 0.0017 – 0.014 0.1 – 1.1 Weak None
IV 0.014 – 0.039 1.1 – 3.4 Light None
V 0.039 – 0.092 3.4 – 8.1 Moderate Very light
VI 0.092 – 0.18 8.1 – 16 Strong Light
VII 0.18 – 0.34 16 – 31 Very strong Moderate
VIII 0.34 – 0.65 31 – 60 Severe Moderate to heavy
IX 0.65 – 1.24 60 – 116 Violent Heavy
X+ > 1.24 > 116 Extreme Very heavy
Peak Ground Acceleration(PGA)
Peak ground acceleration (PGA) is the maximum ground
acceleration that occurred during earthquake shaking at a
location.
• Peak ground acceleration (PGA) Richter and moment magnitude scales
Measures how hard the earth shakes at Ritcher scale measures Intensity (Amount of
a given geographic point. Energy Releases)
PGA is measured by instruments, such The Mercalli intensity scale based on personal
as accelerographs. can be correlated to reports and observations to measure
macroseismic intensities on the Mercalli earthquake intensity
scale but these correlations are
associated with large uncertainty.
Measured in unit of m/s2, go or gal Unitless
(Standard
Base value (Gal, or cm/s2) (ft/s2) (m/s2)
gravity, g0)
1 Gal, or cm/s2 1 0.0328084 0.01 0.00101972
Civil Works & Structural Engineering Branch
Jabatan Kerja Raya Malaysia, Kuala Lumpur
Earthquake Energy:
Beirut Explosion on 4tth Aug 2020 1,100 tons TNT
Source: https://en.wikipedia.org/wiki/2020_Beirut_explosion
Probability of Exceedance
ASCE Specification
Performance Description Mean return Annual probability
level period of exceedance (%)
(years)
Operational Frequent 25 4.0% in 50 years
Immediate Occasional 72 1.4% in 50 years
occupancy
Life-safety Rare 250–800 0.12–0.4% in 50 years
Collapse Maximum Considered 800–2500 0.04–0.12% in 50
prevention (MCE) years
EN 1998-1
Performance Description Mean return Annual probability
Requirements period of exceedance (%)
(years)
No-collapse Rare 475 10% in 50 years
Damage Occasional 95 10 %in 10 years
limitation
NA MS EN 1998-1
Performance Description Mean return Annual probability
Requirements period of exceedance (%)
(years)
No-collapse Rare 475 10% in 50 years
Damage Occasional 95 10% in 10 years
limitation
Civil Works & Structural Engineering Branch
Jabatan Kerja Raya Malaysia, Kuala Lumpur
PGA Contour Map of
Peninsular Malaysia With
A 10% Probability of
Exceedance in 50 Years
PGA Contour Map of Sarawak With A 10% Probability of Exceedance
in 50 Years
PGA Contour Map of Sabah With A 10% Probability of Exceedance in
50 Years
Seismic Load & Design Approach
Seismic Analysis,
Load Design & Assessment
Recorded Ground motion
Dynamic
Static Analysis
Analysis
Macrozonation Response
Map Spectrum
Equivalent Static
Modal & Response
(Lateral Force
Spectral
Method)
Incremental
Non-Linear
Dynamic with Time
Analysis (Push Over)
History
Analysis,
Civil Works & Structural Engineering Branch
Design & Assessment Jabatan Kerja Raya Malaysia, Kuala Lumpur
Methods of Analysis
1) Lateral Force Method of
Analysis (Equivalent Static)
2) Modal Response Spectrum
Analysis
3) Non-Linear (Push Over
Analysis)
4) Time History Analysis
Equivalent Static (Lateral
Force Method)
1.Acquire Design Ground acceleration
from Macrozonation map according
to performance requirements (return
period)
2.Determine importance Factor, gI
according to the importance class
3.Determine Ground Type for Soil
Investigation
4.Specify building type and height
5.Calculate the fundamental period of
vibration, T1
6.Calculate the seismic base shear Fb
7.Distribution of the horizontal Seismic
Force
8.Modelling and analysis Civil Works & Structural Engineering Branch
Jabatan Kerja Raya Malaysia, Kuala Lumpur
Modal & Response Spectral
Analysis
Steps
1.Develop Acceleration Response Spectrum
diagram according to MS EN 1998-1
2.Check minimum mass Participation factor>90%
3.Check Base Shear
Civil Works & Structural Engineering Branch
Jabatan Kerja Raya Malaysia, Kuala Lumpur
Acceleration Response Spectrum
0.05 Mass Participation
0.05
MASS PART. -TRANSLATION (%) SUMM-X SUMM-Y SUMM-Z MASS PART. ROTATION (%)
MODE
X Y Z X Y Z
0.04 1 0 0 81.58 0 0.003 81.577 0 0 0
0.04 2 0.22 0 0 0.224 0.003 81.577 0.64 0 0
3 81.48 0 0 81.708 0.003 81.577 232.46 0 0
0.03
Sd (g)
4 0 0.08 9.48 81.708 0.085 91.06 0 0 0
0.03 5 0 0.04 0 81.708 0.121 91.062 0 0 0
0.02
6 0 2.53 0.01 81.708 2.65 91.067 0 0 0
7 0 6.21 0.02 81.708 8.858 91.084 0 0 0
0.02 8 0 4.85 0 81.708 13.708 91.085 0 0 0
0.01 9 0.04 0 0 81.746 13.708 91.085 0.11 0 0
10 0.02 0 0 81.765 13.708 91.085 0.05 0 0
0.01
11 9.43 0 0 91.19 13.708 91.085 26.77 0 0
0.00 12 0 0 0 91.191 13.708 91.085 0 0 0
0 1 2 3 4 13 0.03 0 0 91.216 13.708 91.085 0.07 0 0
T (s) 14 0.01 0 0 91.221 13.708 91.085 0.01 0 0
15 0 1.9 0.01 91.221 15.604 91.097 0 0 0
Civil Works & Structural Engineering Branch
Jabatan Kerja Raya Malaysia, Kuala Lumpur
Push-Over Analysis
Simplified nonlinear analysis methods, referred to as
Nonlinear Static Analysis Procedures which includes
the capacity spectrum method that uses the
intersection of the capacity (pushover) curve and a
reduced response spectrum to estimate maximum
displacement.
Civil Works & Structural Engineering Branch
Jabatan Kerja Raya Malaysia, Kuala Lumpur
Non Linear Push-Over Analysis
To obtain the maximum shear strength of the
structure, and the collapse mechanism
To evaluate the structure’s collapse mechanism
without exhausting the plastic rotation capacity
of the members
To obtain the monotonic displacement and
global ductility capacity of the structure
To estimate the concentration of damage and IDI
(Inter-storey Drift Index) that can be expected
during the non-linear seismic response.
Non Linear Component
Life Safety
Performance
Structure stability
Level (LS)
Performance Level
Lateral Load
(CP)
1.0 C
B
D
A E
y
Lateral Deformation
Demand Spectra based on different
levels of damping value.
Performance Point
Spectral Acceleration, Sa
Capacity diagram
Spectral Displacement, Sd
Time History Analysis
Time history
analysis is used
to determine
the seismic
response of a
structure under
dynamic
loading of
representative
earthquake.
Civil Works & Structural Engineering Branch
Jabatan Kerja Raya Malaysia, Kuala Lumpur
Fundamental Period Of
Vibration
MS EN 1998-1
Civil Works & Structural Engineering Branch
Jabatan Kerja Raya Malaysia, Kuala Lumpur
Buildings Fundamental
Period vs Height
Civil Works & Structural Engineering Branch
Jabatan Kerja Raya Malaysia, Kuala Lumpur
Mass
Slender
Tuned
Structure
Damper
Buildings Response Under
High Frequency Of Vibration
Base
Isolation
Buckling
Moment
Restraint
Frame
Braces (BRB)
Buildings
Response Under
Low Frequency
Of Vibration
