“Seismic Risk Reduction and Damage Mitigation for Advancing Earthquake Safety of Structures”

The 2 International Conference nd

on Earthquake Engineering and Disaster Mitigation (ICEEDM-II 2011)

“Seismic Risk Reduction and Damage Mitigation for Advancing Earthquake Safety of Structures”

19 - 20 July 2011, Shangri-La Hotel, Surabaya, Indonesia

Full Paper

Indonesian Earthquake Engineering Association

ISBN: 978-602-97462-2-8

LIST OF CONTENT

PREFACE

WELCOMING SPEECH FROM ITS PRESIDENT iii

KEYNOTE AND INVITED SPEAKERS

Seismic Isolation for Housing, Schools and Hospitals in The Urban Environment 1 James M. Kelly and Dimitrios Konstantinidis

The Role ,of IAEE in A Seismically Perilous World Po/at Gulkan

11

Background, Historical Development, and Key Role of Lateral Steel in Enhancing 17 Ductility of RC Members

P. Suprobo, Tavio, B. Suswanto, and D. Iranata

Cumulative Ductility Under Earthquake Loads Adang Surahman

Lessons for Building Safety Evaluation Systems from The 2010 Canterbury Earthquake and Aftershocks

C. W. K. Hyland and S. Wijanto

31

45

Experimental Study and Evaluation on The Seismic Behavior of Coupling Beams 55 E. Lim, C.H. Cheng, and S.J. Hwang

Some Methods to Develop Seismic Vulnerability Functions for Loss Modeling 67 Keith Porter

The Role of Earthquake Vulnerability Research in Risk Mitigation Mark Edwards

69

V

Tehran Seismic Risk and New Hazard-Compatible Urban Planning and School Safety 85 Program

Mohsen Ghafory-Ashtiany

A Practice-Oriented Method for Nonlinear Seismic Analysis of Building Structures 101 P. Fajfar and M Kreslin

Some Recent Efforts in Earthquake Hazard and Risk Analyses for Disaster Risk 113 Reduction in Indonesia

I Wayan Sengara, Masyhur Irsyam, Indra D. Sidi, Widiadnyana Merati, Krishna S.

Pribadi, Made Suarjana, Mark Edwards

Retrofitting of St. Leo Chapel in Padang, Damaged by The September 30, 2009 West 131 Sumatra Earthquake

Teddy Boen and Lenny

Response of Singapore Buildings to A Giant Earthquake in Sumatra Tso-Chien Pan, Kusnowidjaja Megawati, and Key Seng Goh

A. Case Histories in Earthquake Engineering Design and Construction

143

Assessment of Reinforced Concrete Bridge Under Earthquake Resistance Design A-1 Considering Corrosion Effect

A.B.De/ima, Y-C. Ou, IGP. Raka

Synthetic Ground Motion Compatible With SNI-02-1726-2002 Paulus Karta Wijaya , Daisy Natania

B. Case Histories in Recent Earthquake

A-9

Strong Ground Motion by September 30, 2009 Pariaman Earthquake and Damage to B-1 Large Scale Buildings

Mulyo H. Pradono, Yozo Goto, Rusnardi P. Rahmat, Akio Hayashi, and Kazuhiro Miyatake

vi

Lessons Learned from the 2010 Canterbury Earthquake and Aftershocks, New Zealand B-11 Sugeng Wijanto, Clark W.K. Hyland and Takim Andriono

Seismic Performance Evaluation of an RIC Beam-Column Joint Damaged by the 2009 B-19 West Sumatra Earthquake

Yasushi Sanada, Yoshiaki Nitta, Takuya Tomonaga, Yuta Sashima and Maidiawati

C. Community-based Disaster Risk Management

Group Decision in Reducing Impact of Natural Disaster Christiono Utomo and Arazi ldrus

C-1

Lessons for Building Safety Evaluation Systems from the 2010 Canterbury Earthquake C-9 and Aftershocks

Clark W.K. Hyland and Sugeng Wijanto

Strategy for Managing Disaster of Sidoarjo Mudflow I Putu Artama Wiguna and Amien Widodo

D. Geotechnical Earthquake Engineering

Use Of Microtremors For Site Effects Evaluation In Singapore Cheng Zhu, Kusnowidjaja Megawati, and Meya Yanger Walling

Local Site Effect of a Landslide in Jember Based On Microtremor Measurement Dwa Desa Warnana, Ria Asih Aryani Soemitro Widya Utama and Alain Tabbagh

C-19

D-1

D-11

Depth Estimation of Seismic Bedrock of the Kanto Sedimentary Basin of Japan by the D-17 Nonstationary Ray Decomposition Method

Haitao Zheng and Kusnowidjaja Megawati

Characterization of Sediment Cover Based on Fundamental Frequency - Case Study of D-25 Surabaya, Padang and Pariaman

Meya Yanger Walling and Kusnowidjaja Megawati

vii

Random Vibration Theory (Rvt) Based Seismic Site Response Analysis Sindhu Rudianto

E. Non-engineered Buildings

Simple House Earthquake-Resistant With Precast System Harun Alrasyid, Munarus Suluch

D-31

E-1

Comparing Damage to Building Structures Due to the 2009 West Java Earthquake in E-9 Indonesia

H. Choi, Y. Sanada, M Kuroki, M. Sakashita, M Tani, Y. Hosono, S. Musalamah and F. Farida

Study The Traditional Joint Of Bamboo Houses In The Earthquake by Tilting Table E-19 Purwito

F. Performance-based Design

Behavior of RIC Columns Confined With Code Non-Compliance Confining F-1 Reinforcement Plus Supplemental Pen-Binder Under Axial Concentric Loading

A. Kristianto, I. lmran and M. Suarjana

Effect of Suppressing Number of DOF on the Response of NL THA and MP A of a F-11 Rigid Connection RC Multi Span Bridge under Strong Earthquake Motion

B. Budiono, E. Yuniarsyah

Seismic Performance of Structures With Vertical Geometric Irregularity Designed F-21 Using Partial Capacity Design

I. Muljati, B. Lumantarna

Seismic Risk of Important Buildings (Case: Hospitals in Indonesia Recent F-29 Earthquakes)

I. Satyarno

viii

Tire Base Foundation For Earthquake Resistant Houses Ingemar Saevfors

F-37

The Behaviour of Cross Nail-Laminated Timber (CNLT) Shearwall Under Cyclic F-45 Loading

JA. Tjondro and A. Onky

Pushover Analysis of Jacket Structure in Offshore Platform Subjected to Earthquake F-55 with 800 Years Return Period

M. Irmawan, B. Piscesa and I. A. Fada

In-elastic Performance of 2D-Two Bay Ordinary Concentrically Braced Steel Frame F-65 P. Pudjisuryadi, and Tavio

Optimization of Sensor Locations for Bridge Seismic Monitoring System Using F-71 Genetic Algorithms

Reni Suryanita, Azlan Adnan

Evaluation of Performance of Six-Story Structures Using Pushover Analysis in Soft F-79 Soil and Medium Soil

S. A. Nurjannah, Y. Megantara, C. Yudha

A Numerical Study of Three Dimensional Structural Models Controlled by Passive F-89 Tuned Mass Dampers Against Seismic Excitations

S.Shahrokhi, and F.R.Rofooi

Investigation on Performance of Active Tuned Mass Dampers (ATMD) on Vibration F-97 Control of Three-Dimensional Structural Control

S.Shahrokhi , and F.R.Rofooi

Comparing Different Bottom Shear Stress Calculation Method for Irreguler Waves Taufiqur Rachman and Suntoyo

F-107

ix

Prediction of Peak Stress for Concrete Confined with Welded Wire Fabric B. Kusuma, Tavio, and P. Suprobo

G. Probabilistic and Deterministic Seismic Hazard assessment

F-117

Community-Based Open Standards and Data for Hazard Modeling in the Global G-1 Earthquake Model

M. Pagani, H. Crowley, R. Pinho

H. Retrofit, Rehabilitation, and Reconstruction

Shear Strengthening Effect of RC Beams Retrofitted by CFRP Grid and PCM Shotcrete H-1 A. Arwin Amiruddin

Comparison Study of Concentrically Braced Frames (CBF) and Buckling Restrained H-9 Braced Frames (BRBF) on Steel Structure Building Subjected to Earthquake Load

B. Suswanto and D. Jranata

Finite Element Modeling for Reinforcing Steel Subjected to Reversed Cyclic Loading H-19 with Severe Tensile and Compressive Strain Demands

D. Iranata and B. Suswanto

Seismic Response on Jointless Composite Retrofitted Bridges Using Link Slab H-27 H. Sugihardjo

Fracture Mechanics Approach in Determining Pressure and Injection Time To Repair H-37 Concrete Cracks

Jonbi, Ivindra Z Pane

A Study on The Effect of Earthquake Resistant Reinforcement Using Ground H-45 Solidification Body for Underground Structure

K. Urano, Y. Adachi, T. Nishimura, M. Kawamura, and J. Tanjung

X

Behavior of Precast Beam Connections For Seismic-Resistant Houses Under Cyclic H-51 Loading

L.S. B. Wibowo, Tavio, H. Soegihardjo, E. Wahyuni, and D. lranata

Method for Improving Adhesion Between Concrete Structures Surface and External H-61 Fiber System Reinforcing

Mauricio Ivan Panama, Amanda Padilla, Antonio Flores, Luis Rocha

Alternative Strategies to Enhance The Seismic Performance of a Non-Ductile RC H-71 Structure

Marco Valente

Dissipative Friction Devices for Seismic Upgrading of Precast Buildings Marco Valente

Seismic Protection of Steel Structures by Fluid Viscous Devices Marco Valente

H-83

H-93

Rehabilitation of Earthquake-Damaged and Seismic-Deficient Structures Using Fibre- H-105 Reinforced Polymer (FRP) Technology

Ong Wee Keong

Bamboo Use for Earthquake Resistance Housing Sri Murni Dewi

H-111

Behavior of Precast Column Connections For Seismic-Resistant Houses Under Cyclic H-119 Loading

Tavio, H. Soegihardjo, E. Wahyuni, D. lranata, and L. S. B. Wibowo

Incremental Rapid Visual Screening Method for Seismic Vulnerability Assessment of H-127 Existing Buildings

Yadollahi. M, Adnan. A, and Rosli. M Z.

xi

Transverse Stress Distribution m Concrete Columns Externally Confined by Steel H-139 Angle Collars

P. Pudjisuryadi, Tavio, and P. Suprobo

I. Seismic and Tsunami Disaster Mitigation and Management

Damage Mitigation Using Structural Health Monitoring Based on Wireless Sensor 1-1 Networks Technology

Amin Suharjono, Wirawan, Gamantyo Hendrantoro

Minimizing Earthquake Threat To School Building By Using Sustainable Visual 1-11 Assessment And Detail Analysis

Choo Kok Wah, Dr. Rozana Zakaria and Mohd. Zamri Bin Ramli

Evaluation of Building Structure Using Shearwall on Soft Soil By Performance-Based 1-19 Design Method

Christanto Yudha, Yoga Megantara, S.A Nurjannah

Tsunami Evacuation Simulation for Disaster Awareness Education and Mitigation 1-29 Planning of Banda Aceh City

Muzailin A/fan, Yozo Goto and Agussabti

Test of Coupling Beam Systems with an Energy Dissipation Device Taesang Ahn, Youngju Kim and Sangdae Kim

I-45

Evacuation Response of the People in Meulaboh after the May 9, 2010 Earthquake 1-51 Yudha Nurdin, Diyah K. Yuliana, Ardiansyah, Muzailin A/fan and Yozo Goto

J. Seismic Zonation and Microzonation

Shear-Wave Velocity Structure Underneath Surabaya Inferred From Microtremor J-1 Survey

Kusnowidjaja Megawati, Xiaofang Deng, Meya Yanger Walling and Hiroaki Yamanaka

xii

Site Response Evaluation for Earthquake Hazard Analysis of Surabaya Metropolitan J-9 M Farid Ma 'ruf, Amien Widodo, and Suwarno

Soil-Structure Resonance Base on Observations of Horizontal-To-Vertical Spectral J-15 Ratios of Microtremor (Case Study: Pare, Kediri District-East Java)

Triwulan, W. Utama, D.D. Warnana and Sungkono

K. Soil-structure Interaction

Effect of Soil Condition on Response Control of Adjacent Structures Connected by K-1 Viscous Damper

Chirag Patel

L. Tsunami Modeling

Numerical Modeling of Tsunami

M Cahyono, Gneis Setia Graha and Andi Abdurachim

M. Tsunami Early Warning System N. Disaster Management

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Visualisation in The Implementation of Seismic Codes on Residential Houses as an N-1 Educational Tool For Construction Actors

Setya Winarno

0. Any Related Topics

Identification of Dynamic Characteristics of a Building Using Recorded Seismic 0-1 Response Data

Agung Budipriyanto

Development of Artificial Neural Networks With Different Value of Learning Rate and 0-11 Momentum For Predicting The Compressive Strength of Self Compacting Concrete at

28 Days

Akhmad Suryadi, Triwulan, and Pujo Aji

xiii

Response of Adjacent Structures Connected by Friction Damper Chirag Patel

Progressive Collapse of RC Frames Under Blast Loading Elvira

0-23

0-33

Structural Behaviour of Submerged Floating Tunnels With Different Cable 0-43 Configurations Under Seismic Loading

Endah Wahyuni, IGP Raka, Budi Suswanto and Ery Budiman

Study of Eccentricity Effects on Reduction Factors of Square Reinforced Concrete 0-53 Columns Using Visual Basic 6.0 Program

Iman Wimbadi, Tavio, and Raditya Adi Prakosa

Numerical Simulation of Seismic Wave Propagation Near a Fluid-Solid Interface 0-63 Pranowo, Y. A. Laksono, W. Suryanto, Kirbani SB

Behavior of Hybrid Reinforced Concrete T-beams with Web Opening under Monotonic 0-77 Loading

Tanijaya, J.

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NUMERICAL MODELING OF TSUNAMI PROPAGATION

M. CAHYONO¹"t, GNEIS SETIA GRAHA¹, and ANDI ABDURACHIM¹

1Faculty of Civil and Environmental Engineering and Engineering Centre for Industry, Institute of Technology Bandung (1TB), Bandung, Indonesia

ABSTRACT

A numerical model has been developed to accurately simulate tsunami propagation from deep ocean waters to shallow water and coastal areas. The model employed a Boussinesq-type equation to consider dispersion effect on a sloping beach. The Boussinesq-type equation was solved using a shock-capturing type of Mac-Cormack scheme to accurately describes steepening waves, propagating bores and breaking waves when tsunami wave approaching shallow waters and dry lands. The accuracy of the model is verified by recourses to several benchmarking tests, including experiments for breaking and non-breaking waves and a sinusoidal wave propagating over a bar.

The model can reasonably describes propagation of non-breaking and breaking waves on a sloping beach, with the computed surface elevations, run-up and attenuated wave heights showing good satisfactory agreement with experiment observations. Good agreement between the wave profile computed by the model and the corresponding profile obtained in the experiments were also obtained. The numerical experiments simulating the Indian Ocean Tsunami on December 26, 2004 and October 2010 have been conducted. The comparisons between inundations obtained m simulations and their corresponding field measurements showed reasonable agreements.

Keywords: tsunami model, Boussinesq-type equation, breaking wave, attenuated wave, shock capture method.

1. INTRODUCTION

After the destructive events of Indian Ocean tsunami at Sunday, December 26, 2004 in Aceh, and at Monday, October 25, 2010 in Mentawai, there have been substantial interests in developing tsunami mitigation plans for tsunami hazard reduction at tsunami prone regions. The plans include the development of hazard and risk assessments. For this purpose the development of the tsunami models for accurately simulate the propagation of tsunami waves from its source, usually triggered by tectonic earthquake in deep ocean water, to shallow and coastal waters are urgently needed to ensure a maximum level of quality and reliability for real-time forecasting and inundation mapping product. The model should have a capability to describe complex evolution phenomena, including

• Corresponding author: E-mail: mcahyono@ftsl.itb.ac.id t Presenter: E-mail: mcahyono@ftsl.itb.ac.id

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run up, breaking waves and propagating bores when tsunami wave approaching shallow waters and dry lands. Thus, the model has to be able to accurately estimate the maximum run up and inundation depth over wide ranges of tsunami waves.

In deep ocean water the dispersion effect could be significant factor for accurate prediction of tsunami propagation. Boussinesq-type equations are well-suited to simulate wave propagation in this area. However, in the sallow waters as dispersive terms becomes small compared to nonlinear terms, the Boussinesq equation degenerate into nonlinear shallow water equation (NSWE). Thus, the model equations which include both dispersive and nonlinear combination terms are need for better prediction of tsunami phenomena in the coastal area. In this study the numerical model of the tsunami propagation has been developed based of the Boussinesq type equation. In region where dispersive term and non-linear effects are both relevant for the tsunami propagation the model applies the Boussinesq equation and when tsunami wave reach shallow water area where the non-linearity is predominant with respect to dispersive terms, such as at region after breaking point, the model uses the NSWE by turning of the dispersive part of the governing equations. The equations were solved using Maccormack scheme. The modified TVD Filter was incorporated into the model for better capturing a shock as wave steep increasing or/and breaking when tsunami wave propagating shallow waters and dry lands.

2. GOVERNING EQUATIONS

The model uses the 2-D depth averaged equation. However, in this paper only the 1-D model results are reported. The 1-D model for propagation of tsunami wave is based on the following equation.

(1)

(2)

where h is the water depth, u is the depth-averaged velocity, g is the gravitational acceleration, S0 is the bottom slope, Sr is the friction slope, and E is the Boussinesq-terms. The Boussinesq terms and friction term are defined as

(3)

(4) where n is the Manning's coefficient and R is the hydraulic radius.

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The equation (1) and (2) can be written in the conservative form as:

aw

at + 8F(W) = T(W)

ox

where cp is a parameter defined by

2.1. Numerical Solution

(5) (6)

(7)

The equation (6) is solved by using the Maccormack scheme consisting the predictor - corrector steps. In the predictor step we have

and in the corrector step we solve

= �t (- - ) -

w.

_J =W." -- F -F_J �x ^{J J-}_I -�tT.^J

The values of W at new time level (n+ 1) are computed from

I

ll- =)

w�

_J ^{+ =-}₂

w.

_J +

w . .

_J

(6)

(7)

(8) The values of u and h at time level (n+ l) are obtained by solving (7) using the Thomas algorithm to solve tridiagonal matrix system. The modified non-linear TVD filter is included in the model to better capturing wave breaking and to accurately model bore propagation. The TVD filter was originally proposed by Engquist et al (1989) and then was modified by Cahyono (2000). The modified TVD filter can accurately detect the true extreme such as peak of breaking wave and then avoiding it flattened by the filter.

3. RESULTS AND DISCUSSIONS 3.1. Laboratory experiments

The numerical simulation was verified with several benchmark tests, including laboratory experiments of Synolakis and a wave propagation over a submerged bar in laboratory experiment by Yamazaki et al.

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Non-breaking wave and breaking wave

Synolakis conducted several laboratory experiments to examine the propagation of solitary wave on sloping beach (Synolakis, 1987). The experiment set-up condition was 36.60-m-long, 0.38-m-wide, and 0.61-m-deep with a beach slope 1: 19.85, which similar to the Synolakis experiments. The non-breaking wave and breaking wave conditions were tested with two different ratio of wave height/water depth, Hid. These were H/d = 0.0185 and Hid= 0.3, respectively. Figure 1 shows the computational domain, consisting of 60.0 m length with 36.6 m flat area and 23.6 m ramp. The model uses grid size of the mesh, �x = 0.2 m and the time step, �t = 0.001 s.

H d

L

Figure 1: Sketch of solitary wave on plane beach

The initial depth profile is defined by:

ri(x,0)== Hsech²(y(x -X1)!d)

where X1 = X0 + L, X0 = d cot�, y =

✓

^{3H/4d3 ,} and L == arccosh(.Jwh.

The initial wave velocity is set up by the following equation (Nicolsky D. J. et al. 2010).

u(x,0 )=

.Jgid. ·

ri(x,0)

The results are given in the dimensionless variables defined by x=xd,

(9)

(10)

where rt = the amplitude, u is the depth-average velocity, and h⁰ is the undisturbed water depth (Synolakis 1987). The comparison between Synolakis experimental results and numerical simulation results are shown the Figure 2 and 3. As can be seen the overall agreement is satisfactory for the non-breaking case. For the breaking case, the model produced accurate prediction of the location of the wave breaking, however the model still give slightly under prediction of wave height at breaking point.

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•O•

IU ^ii.ti t(tt/hl"<l/2) ..-50

11\J

I ^HI

"

QI

,u ., ^d

, ..

,.

..

_n ^,

_..

.

_� • ^I

t•II I

1101

•l II j\

... .. .

t(g/h}'\{l/2) • 50

o: ¹¹

Figure 2: Surface water profile of solitary wave on a 1:19.85 w�th Hid= 0.0185 (non-breaking case)

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u II

t(i/h)"{l/21 " 1 S 1

D II l"Jo

.,.

�� • ,..., .. CMI• -•,.

t(l/ht"{l/21 = zo

" ^JI

r :

I -� _•..

I u

It ^u

u

• W JS

.,. ..

^H

Figure 3: Surface water profile of solitary wave on a 1:19.85 with Hid= 0.3 (breaking case)

3.1.1. Wave propagation over a submerged bar

The laboratory experiments were conducted to examine sinusoidal wave propagation over a submerged trapezoidal bar (Yamazaki et al. 2008). The submerged trapezoidal bar was 0.3 m high with front slope of 1 :20 and lee slope of 1: 10 The laboratory experiment was equipped with five gauges as can be seen in the Fi_gure 4 below.

4 5 8 7 8 0.0

-40,0

0 5 6 10 12 1416 17 20 26 30

OIGtonoe (m)

Figure 4: Sketch of wave transformation over a submerged bar

The computational domain employes 35.0 m length. The grid size of the mesh is �x = 0.025 m and the time step is �t = 0.01 s. Wave amplitude in left boundary condition is given by:

TJ = 0.01 *sin(2*rr/2.02*time)

The comparison between experimental result and numerical simulation results are shown in the Figure 5. As can be seen, the model can produce satisfactory results particularly at point 4, 5, 6 and 7.

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gauge 4

"

^{B II}

" •

_�

----r:-- o�g8

I'

I

�

.. ..

^"

.. ..

Figure 5: Surface water profile of sinusoidal wave transformation over a submerged bar 3.2. Meulaboh Case Study (Aceh Tsunami, December 26, 2004)

The earthquake epicenter was located at longitude 94.17^° and latitude 3.07^° with fault parameters were 300 km-length, 150 km-width, 13-dip, and 10 km-depth (PT. Gitamandala Consultant 2008).

The earthquake triggered the initial wave that caused the tsunami wave. In this paper, Mansinha and Smylie method (1971) was applied to predict the initial wave. Figure 7 shows the initial wave prediction.

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2.0 1.0

Oopth(mtt----�-�-o.o-11---�---i

.3 0 -200 ·100 100 200 l D

Ol1h1nre (km)

Figure 6: Initial wave Figure 7: Aceh Bathymetry

Meulaboh City, located at latitude 96.17^° and longitude 4.13^°, was hit by the tsunami on December 26, 2004. The 1-D numerical simulation was conducted to simulate the tsunami wave propagation along Epicenter - Meulaboh beach during the time. The simulation results are shown in Figure 8. A good agreement between the simulation results and field survey measurements is found. The measurements of wave height (Satuan Tugas Penanggulangan Bencana Aceh 2005) at Meulaboh area ranged from 8 to 16 m at Meulaboh City. Theses values are close to the simulation prediction of 7.89 m at shoreline. The simulation also indicate that the tsunami wave reaches the shoreline after 50 minute propagation and inundates costal area up to approximate 7 .0 km from shoreline with the highest water level of 7.89 m.

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•

•

---- _____ .. ^.,. __ _

-41 ,Ii .j ,t ii '

.,..,...

- 1 I ' l t ■ • llflll

I j

....

I 1• 1,0 mlnore

. . ^..

..

r�!IO mlnure

' "' • ... 6 \ .- _.,.. 1 I i'. 1 ,.; J I I - f b

r ' ^{j .,} _'J ^f

J

Figure 8: The propagation along Meulaboh beach 3.3. Mentawai case study (October 25, 2010)

Bosua, located at latitude 2^°21.9' and longitude 99^°48.2', was one of the villages in Mentawai Island that had a great impact of tsunami at Monday, October 25, 2010. The 1-D numerical simulation was conducted to simulate the wave propagation along Epicenter to Bosua village during that tsunami event.

2.0 1.0

0,,,111 .. )f---�----<1.11,..._-4--�--­

•i 0 •100

·1.0

Olii.nco (km)

Figure 9: Initial wave at Mentawai Island Figure 10: Mentawai Island Bathymetry

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The earthquake epicenter was located at longitude 100,114^° and latitude 3,848^° with fault parameters were 95 km-length, 48 km-width, 7^°-dip, and 12 km-depth (http://www.tsunami .civi l.tohoku.ac. j p/hokusai3/J/events/sumatra l O 1025/sumatral O L025 .html).

That earthquake triggered the initial wave that caused the tsunami. Fi_gure 9 shows the initial wave prediction computed using Mansinha and Smylie method (1971). The tsunami wave profiles at the Bosua area simulated by the model are shown in Fi_gure 11. The results show a good agreement between the numerical simulation results and field survey measurements (Achiari 2010). The measurements of inundation depth at the Bosua village were between 2.55 m and 4.81 m, while the corresponding model result at this location is 6.08 m after 35 minute propagation. The model predicted that the tsunami wave reaches the shoreline after 15 minute propagation and inundates the shoreline up to 4 km with the highest water depth of 6.08 m .

.•

I •

L.

I •

..

t • 15 minute

� r-•��-�• ••• •••••••----4-••••-•••-- I I

__

^,_

t • 35 mlnuta

... •·•--- I •

. ^..

L.

. .

^•

-

^I

taJSO mlnllle

-

Figure 11: The propagation along Bosua beach 4. CONCLUSIONS

The non-breaking and breaking waves on a sloping beach were accurately described in the model with the computed surface elevations, run-up and attenuated wave heights showing good agreement with experiment observations. The model can produced reasonable tsunami wave run up and inundation depth in coastal area for simulation of real time tsunami event in the Indian Ocean for both the tsunami events, including the tsunami event on December 26, 2004 (study case at Meulaboh) and the tsunami event on October 25, 2001 (study case at Bosua Mentawai).

5. ACKNOWLEDGMENTS

This study was financial supported by Competitive Research Grant, ITB, Ministry of Education, 2010.

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REFERENCES

Achiari, H. (2010). Laporan Hasil Kunjungan Lapangan Survey Pasca Tsunami Mentawai 2010. LPPM, ITB.

Cahyono, M (2000),"TVD Filter Algorithm for Solving Advective Transport Equations", Proceeding 1TB Vol 32 No l . Engquist, B., Lotstedt, 0., and Sjogreen, B., !989, Nonlinear Filters for Efficient Shock Computation, Mathematics of

Computation, Vol.52, No.186, April, pp.509-537

Jaffe, B.E.; Borrero, J.C.; Prasetya, G.S.; Peters, R.; McAdoo, B.; Gelfenbaum, G.; Morton, R.; Ruggiero, P.; Higman, B.; Dengler, L.; Hidayat, R.; Kingsley, E.; Kongko, W.; Lukijanto.; Moore, A; Titov, V.; and Yulianto, E.

(2006).

Mansinha, L.; and Smylie, D. E. ( 1971 ). The Displacement Fields of Inclined faults. Bulletin of the Seismological Sodety of America, Vol. 61, No. 5, pp. 1433-1440.

Nicolsky, D.; Suleimani, E.; and Hansen, R. (2010). Validation and Verification of Numerical Model for Tsunami Propagation and Runup. Pure and Applied Geophysics.

Northwest Sumatra and Offshore Islands Field Survey after the December 2004 Indian Ocean Tsunami. Earthquake Spectra, Volume 22, No. S3, pages Sl 0S-S135.

PT. Gitamandalaksana Consultant. (2008). Final report: Identifikasi zona sumber-sumber gempa dan probabilistic bahaya tsunami sebagai bahan perumusan kebijakan pembangunan di Kota Banda Aceh, Provinsi NAD (Paket-1).

Satuan Tugas Penanggulangan Bencana Aceh. (2005). Laporan Kajian Awai dan Survey Lapangan Pasca Gempabumi dan Tsunami Aceh 26 Desember 2004. ITB.

Synolakis, C. (1987). The Runup of Solitary Waves. Journal of Fluid Mechanics 185, 523-545.

Synolakis, C; Bernard, E.; Titov, V.; Kanoglu, U.; and Gonzalez, F. (2008). Validation and Verification of Tsunami Numerical Models. Pure and Applied Geophysics 165, 2!97-2228.

Yamazaki, Y.; Kowalik, Z.; and Cheung, K. (2008). Depth-integrated, Non-hydrostatic Model for Wave Breaking and Run-up. International Journal for Numerical Methods in Fluid.

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