September 24 ‐ 26, 2013 Bali, Indonesia
Proceedings of the Seventh International Conference on Asian and Pacific Coasts
Asian and Pacific Coasts 2013
Editors
Dadang A. Suriamihardja T. Harianto
M. A. Abdurrahman
T. Rachman
Proceedings of the 7
thInternational Conference
On
ASIAN AND PACIFIC COAST
APAC 2013
September 24 – 26, 2013 Bali, Indonesia
ORGANIZED BY
Hasanuddin University
Proceedings of the International Conference on ASIAN AND PACIFIC COAST 2013
PEER REVIEWED
Editors-in-Chief: Dadang A. Suriamiharja
Associate Editors: T. Harianto, M. A. Abdurrahman and T. Rachman Published by:
Hasanuddin University Press
Tamalanrea, Makassar 90245, Indonesia Tel: 62-411-586200
Fax: 62-411-585188 Email: [email protected] URL: http://www.unhas.ac.id
Every paper published in the proceedings was peer reviewed by two referees in the appropriate professional field.
The Hasanuddin University is not responsible for the opinion expressed by various authors in their contributions presented in the Proceedings.
I S B N : 978-979-530-125-7
Printed in Indonesia
COVER PHOTO (FRONT) Source : http://images.detik.com/content/2013/06/14/4/tol4.jpg
iii
7
thInternational Conference on Asian and Pacific Coast APAC 2013
APAC Council
ZUO, Qihua (Chair) Nanjing Hydraulic Research Institute, China CHOI, Byung Ho Sungkyunkwan University, Korea
MIZUGUCHI, Masaru Chuo University, Japan PYUN, Chong Kun Myongji University, Korea
QIU, Dahong Dalian University of Technology, China
XIE, Shileng First Design Institute of Navigation Engineering, China
APAC International Steering Committee
CHENG, Liang The University of Western Australia, Australia HUANG, Zhenhua Nanyang Technological University, Singapore KIOKA, Wataru Nagoya Institute of Technology, Japan
LEE, Joseph Hun-Wei The University of Hong Kong, Hong Kong, China LI, Yucheng Dalian University of Technology, China
LIN, Ming-Chung National Taiwan University, Taiwan, China LIU, Philip L.F. Cornell University, USA
NADAOKA, Kazuo Tokyo Institute of Technology, Japan OU, Shan-Hwei Tajen University, Taiwan, China SHIBAYAMA, Tomoya Waseda University, Japan SUH, Kyung-Duck Seoul National University, Korea
SUNDAR, Vallam Indian Institute of Technology, Madras, India YAMASHITA, Takao Hiroshima University, Japan
YU, Xiping Tsinghua University, China
YUM, Ki Dai Korean Ocean Research & Development Institute, Korea
APAC2013 International Scientific Committee
BAI, Yuchuan Tianjin University, China
CHIEW, Yee Meng Nanyang Technological University, Singapore DAVIDSON, Mark University of Canterbury, New Zealand
HWUNG, Hwung-Hweng National Cheng Kung University, Taiwan, China ISOBE, Masahiko The University of Tokyo, Japan
KAO, Chia Chuen National Cheng Kung University, Taiwan, China LARSEN, Ole DHI-NTU Centre, Singapore
LAW, Adrian Wing-Keung Nanyang Technological University, Singapore LIN, Pengzhi Sichuan University, China
LIU, Cheng International Research and Training Centre on Erosion and Sedimentation, China
LIU, Hua Shanghai Jiaotong University, China
LO, Edmond Yat-Man Nanyang Technological University, Singapore
iv
LU, Dong-qiang Shanghai University, China TAJIMA, Yoshimitsu The University of Tokyo, Japan
TAN, Soon Keat Nanyang Technological University, Singapore TANAKA, Hitoshi Tohoku University, Japan
TAO, Jianhua Tianjin University, China
Thanh, Vu Dinh Ho Chi Minh City University of Technology, Vietnam
WAN, Decheng Shanghai Jiaotong University, China
WANG, Xiaohua The University of New South Wales, Australia YEH, Harry Oregon State University, USA
YUAN, Yeli The First Institute of Oceanography, State Oceanic Administration, China
ZHANG, Changkuan Hohai University, China
Chiu-On Ng University of Hongkong, China Saleh Pallu Hasanuddin University, Indonesia
APAC 2013 Local Organising Committee
Dadang A. Suriamihardja (Chair) Hasanuddin University, Indonesia Tri Harianto (Co-chair) Hasanuddin University
A. Yasir Baeda (Secretary) Hasanuddin University Hasdinar Umar (Treasurer) Hasanuddin University Isran Ramli Hasanuddin University
Hendra Achiari Bandung Institute of Technology Nur Yuwono The University of Gadjah Mada
H. Nizam The University of Gadjah Mada
Suntoyo Sepuluh November Institute of Technology Subandono Ministry of Maritime Affairs and Fisheries Sabaruddin Rahman Hasanuddin University
Bannu Abdul Samad Hasanuddin University Arsyad Thaha Hasanuddin University Alimuddin Hamzah Hasanuddin University Khaeruddin Nurdin Hasanuddin University Alham Djabbar Hasanuddin University Daeng Paroka Hasanuddin University Magdalena Litaay Hasanuddin University
Lukman Hasanuddin University
Chairul Paotonan Hasanuddin University Mukhsan P. Hatta Hasanuddin University Taufiqur Rahman Hasanuddin University M. Asad Abdurrahman Hasanuddin University St. Hijraini Nur Hasanuddin University
v
PREFACE
Major cities in many countries have been developed in low-lying area exposing to various stresses from nature and human treats. As a result, natural coast are turned into highly vulnerable area in safety, economic and environmental aspect. New record of the highest temperature and precipitation in many regions of the world has challenged the knowledge and technology for protecting life, property, and ecological system.
The aim of APAC conferences is to promote technological progress and activities, international technical transfer and cooperation, and opportunities for engineers and researchers to maintain and improve scientific and technical competence in the field of coastal engineering and other related fields. It is further intended to provide an international forum for the academic and technical activities, cooperation, opportunity and fellowship among researchers and engineers, and to exchange experience of coastal and port engineering development, and coastal environmental problems among Asian and Pacific countries. The First Asian and Pacific Coastal Engineering Conference (APACE 2001) was held in Dalian, China in 2001. The second conference (APAC 2003) was convened in Chiba, Japan in 2004 and the third one (APAC 2005) took place in Seogwipo, Korea in 2005.The fourth and the fifth conference were held in Nanjing, China and Singapore in 2007 and 2009 respectively. The sixth APAC was held in Hongkong in 2011. APAC 2013 covers seven conference topics: ocean wave, tides, storm surge and tsunami, coastal preservation and sediment transport, climate change and coastal adaptation, lowland development, marine ecology and environments, marine renewable energy, and coral reef preservation.
This conference, APAC 2011, is organized by Hasanuddin University, Makassar, Indonesia and supported by the Chinese Ocean Engineering Society, Coastal Engineering Committee of Japan Society of Civil Engineers, and Korean Society of Coastal and Ocean Engineers, and their gratitude to all the experts for their hardworking in paper review. In this year, the word “Asian and Pacific coast” has brought together 200 researchers and engineers in related fields from 14 countries to share their great experience on coping with various problems in coastal area.
I sincerely wish to express my gratitude to the international and local organizing committee for their great contribution. Finally, I would like to thank all the authors for their participation. Without all of you, the symposium will never be successful.
Dadang A. Suriamihardja Local Chairman of APAC 2013
vi
CONTENTS
Preface ... v
PART 1
COASTAL PRESERVATION AND SEDIMENT TRANSPORT
VERIFICATION OF SHORE PROTECTION EFFECT OF BEACH NOURISHMENT ON CHIGASAKI COAST
T. Ishikawa, T. Uda, T. San-nami and J. Hosokawa ... 1
EFFECTS OF ANTHROPOGENIC FACTORS ON DEVELOPMENT OF SAND SPITS AND CUSPATE FORELANDS WITH RHYTHMIC SHAPES
M. Serizawa, T. Uda and S. Miyahara ... 9
PREDICTION OF TOPOGRAPHIC CHANGES OF A CIRCULAR SANDY ISLAND USING BG MODEL
S. Miyahara, T. Uda and M. Serizawa ... 17
CHANGE IN CARBONATE BEACH TRIGGERED BY CONSTRUCTION OF A BRIDGE ON IRABU ISLAND AND ITS SIMULATION USING BG MODEL
T. Uda, M. Gibo, T. Ishikawa, S. Miyahara, T. San-nami and M. Serizawa ... 24
ANALYSIS OF MECHANISM OF SAND DEPOSITION INSIDE A FISHING PORT USING BG MODEL
Y. Ohki, T. Uda, S. Miyahara, M. Serizawa, T. San-nami and A. Sumita ... 32
NUMERICAL STUDY ON THE RESPONSE OF SHORELINE CHANGE TO THE TIDAL CHANNEL AFTER A BEACH NOURISHMENT PROJECT ON AN EMBAYED BEACH
Y. Pan, C.P. Kuang, Y.X. Yang, J.B. Zhang and R.F. Qiu ... 40
NUMERICAL SIMULATION AND DEPOSITION PREDICTION FOR NEW DEVELOPED DEEP WATERWAY IN SILTING SHOALS
Gao Z.R., Zhang W.S, Jia N.Y. and Zhang J.S ... 44
NUMERICAL PREDICTIONS FOR EQUILIBRIUM PROFILE ON INTERTIDAL FLAT
L. Manu, H. Shiraishi, R. Yamaguchi, F. Yamada and S. Nakajo ... 50FIELD EXCURSION TO ENHANCE COASTAL AND ENVIRONMENTAL
ENGINEERING CAPACITIES OF ENGINNERS IN ADMINISTRATIVE POSITIONS
S. Seino, T. Uda and Y. Ito ... 56AN IMPROVED SHORT-TERM SWASH ZONE BEACH PROFILE CHANGE MODEL FOCUSING ON BERM FORMATION AND EROSION
T. Suzuki , S. Isozaki and J. Sasaki ... 63
BASIC STUDY ON THE ESTIMATING THE VALUE OF SAND BEACH USING AMENITIESREPLACE
B-S. Shin and K-H. Kim ... 69
vii
ANALYSIS OF BEACH EROSION BY STORM USING ARTIFICIAL NEURAL NETWORK
Y.H. Park and J.-H.Yi ... 75
EFFECT OF THE COASTAL CONSERVATION DUE TO BEACH NOURISHMENT OF TOTORI SAND DUNE COAST
Y. Shibutani, Y. Matsubara and M. Kuroiwa ... 79
ANALYSIS OF COASTAL EVOLUTION OF THE PEARL RIVER ESTUARY BASED ON REMOTE SENSING AND GIS
Y. Xu, J. Zheng , W. Zhang and Y. Zhao ... 85
INFLUENCE OF LONG-PERIOD VARIATION ON SHORELINE CHANGE
S. Kato, T. Okabe and N. Sawahara ... 91
STUDY ON THE DESIGN SCHEMES OF MARINE WARNING AND FORECASTING SYSTEM PLATFORM
C. Xiu-ying, C. Hong-sheng, and F. Ping-yi ... 96
THE INFLUENCE OF RILL DENSITY ON SOIL EROSION AGAINTS USLE-SOIL EROSION METHOD
A. M. Rizalihadi, B. E. Fatimah and C. L. Nazia ... 101
STUDY ON LOCAL SCOURING AT SURAMADU BRIDGE PIERS FOR STRUCTURAL INTEGRITY MONITORING
H. D. Armono and A. Budipriyanto ... 107
BEACH EROSION TRIGGERED BY RIVER MOUTH DREDGING AS A MEASURE AGAINST RIVER MOUTH CLOSURE
A. Kobayashi, T. Uda, M. Endo and Y. Noshi ... 113
TOPOGRAPHIC CHANGES ON AJIGAURA BEACH TRIGGERED BY ELONGATION OF OFFSHORE BREAKWATER
Y. Noshi, T. Uda, M. Serizawa and T. Kumada ... 121
AN APPROACH OF COASTAL PROTECTION AND DEVELOPMENT IN SEMI-CLOSED BAY
A. Ma-Jinrong, B. Guo-Yaqiong and C. Tan-Lixiong ... 130
STUDY ON COMPREHENSIVE TECHNIQUES OF CONSTRUCTING A DEEPWATER CHANNEL OF TIANJIN PORT
S. Liancheng and Z. Na ... 135
ANALYSIS OF BEACH SAND COLOR AND ITS APPLICATION TO SEDIMENTATION
G. Tsujimoto and M. Tamai ... 141
STUDY ON ARTIFICIAL ISLAND PORT IN BEIBU GULF
A. Ma Jinrong, B. Guo Yaqiong, C. Lin Kunqiang and D. Wang Zhimin ... 147
viii
MORPHOLOGICAL CHANGES AND VEGETATION INDEX VARIATION ALONG THE WESTERN COASTAL ZONE OF BANGLADESH
A. Md. Shibly and S. Takewaka ... 153
THE PREDICTION OF THE EFFECT OF OCEAN ENGINEERING ON JINTANG TIDAL CHANNEL EVOLUTION
Z. Jinshan, W. Jinhua, C. Xiangyun and Z. Qingyang ... 159
CHARACTERISTICS OF SPLASH RUN-UPS GENERATED AT VERTICAL COASTAL STRUCTURES
M. Yamashiro, A. Yoshida, S. Kaida and Y. Nishii ... 166
WAVE-CURRENT INTERACTION IN FORMATION OF RIP CHANNEL SYSTEM
Y.Uchiyama, H. Kaida, and D. Miyazaki ... 173
HYDRAULIC STABILITY FORMULAE AND NOMOGRAMS FOR COASTAL STRUCTURES MADE OF GEOTEXTILE SAND CONTAINERS
D. T. Dassanayake and H. Oumeraci ... 180
TIDAL CHARACTERISTICS AFFECTED BY DYNAMIC MORPHOLOGY CHANGE IN THE MEGHNA ESTUARY
M. A. Hussain, Y. Tajima, Y. Taguchi and K. Gunasekara ... 187
BALI BEACH CONSERVATION PROJECT AND ISSUES RELATED TO BEACH MAINTENANCE AFTER COMPLETION OF PROJECT
S. Onaka, S. Endo and T. Uda ... 198
SEDIMENT TRANSPORT AROUND PORT DEVELOPMENT AREA IN ESTUARY
M. Chen, F. De Smedt and S. Wartel ... 204PHYSICAL MODELING RESEARCHES ON THE IMPROVEMENT PROJECT OF THE DEEP-DRAFT CHANNEL OF THE YANGTZE ESTUARY
Y. Han, Z. Chen, X. Luo and X. Wang ... 209
IMPACT ANALYSIS OF SUBMERGED FLOATING TUNNEL FOR EXTERNAL COLLISION
Y. Lee, D.-M. Kim, S.-H. Han and W.-S. Park ... 214
STUDY OF WAVE PROPAGATION INDUCED BY SEA DIKE BREACHING
Z. P. Zhou, Q. H. Zuo and Y. R. Zhou ... 220
A STUDY ON THE LONGSHORE SEDIMENT TRANSPORT RATE AROUND A HEADLAND
S. An and S. Takewaka ... 227
FREQUENT MONITORING OF EBB-TIDAL DELTA FORMATION IN IMAGIRE-GUCHI INLET AREA
T. Okabe and S. Kato ... 234 .
STRENGTH TEST OF SERRATED BEAM FOR ARMOR LAYER BREAKWATER
Tamrin, Shaleh Pallu, Herman Parung, and Arsyad Thaha ... 238
ix
THE ANALYSIS OF THE USE OF SAND COLUMN IN RECHARGE RESERVOIR AS SEAWATER INTRUSION BUFFER
A.Azis ... 243
RESEARCH ON ENTRANCE TRAINING AND RECLAMATION PROJECT OF DONGSHUIGANG, CHENGMAI COUNTY, HAINAN
A.D. Xiping, B. G. Xiangyu and C. Z. Xinzhou ... 248
A METHOD FOR INVESTIGATION OF SEDIMENT RETENTION IN SANDY TIDAL FLATS
N. Touch, T. Nakaoka, Y. Nagatsu and T. Hibin ... 254
STUDY ON EROSION CONDITION AND RESTORATION COUNTERMEASURES OF SANYA BAY BEACH
W. Yanhong ... 261
A NEW MODEL FOR SEDIMENT TRANSPORT RATE UNDER OSCILLATORY SHEET FLOW CONDITIONS
X. Chen and X. Yu ... 266
LONG-TERM SHORELINE RECESSION ON EASTERN BALI COAST CAUSED BY RIVERBED MINING
T. San-nami, T. Uda and S. Onaka ... 275 .
DYNAMIC BEHAVIOR OF SUBMERGED FLOATING BRIDGE DUE TO MOVING HIGH SPEED TRAIN
J.W. Kwark, M.Y. Kim, D.J. Min, J.W. Lee and E.S. Choi ... 283
DISAPPEARANCE OF SANDY BEACH TRIGGERED BY EXTENSION OF FISHING PORT BREAKWATER AND EXCESS LAND RECLAMATION
M. Endo, A. Kobayashi, T. Uda and Y. Noshi ... 288
THE STUDY ON WAVE RUN-UP ROUGHNESS AND PERMEABILITY COEFFICIENT OF STEPPED SLOPE DIKE
W. Xiaomin, JU. Liehong and F.M.Treuel ... 295
SHORT-TERM EBB TIDAL DELTA VARIABILITY USING VIDEO IMAGERY AND MBES SURVEYS
A. Y. Ramli and W. de Lange ... 300
GEOTECHNICAL ASPECTS OF COASTAL RECLAMATION PROJECTS
H.E. Ali and J.S. Damgaard ... 311
INLET STABILISATION USING FLOW REGULATION, A NUMERICAL APPROACH USING PROCESS-BASED MODELING
T. T. Tung ... 319
DEVELOPMENT OF 3D BEACH EVOLUTION MODEL FOR SAND NOURISHMENTS AND ITS APPLICATION TO MORPHODYNAMICS AROUND COASTAL
STRUCTURES
M. Kuroiwa, Y. Matsubara, H. Fujitani and H. Mase ... 326
x
MODELING OF DAMAGE PROGRESSION FOR RUBBLE MOUND REVETMENT
T. Ota, Y. Matsumi, A. Hatono and T. Satow ... 332SEDIMENT TRANSPORT CALCULATION CONSIDERING COHESIVE EFFECTS AND ITS APPLICATION TO WAVE-INDUCED TOPOGRAPHIC CHANGE
Y.H. Cho, T. Nakamura, N. Mizutani and K.H. Lee ... 338
IDENTIFICATION OF THE CONDITION OF SEA BOTTOM SEDIMENT BASED ON IGNITION BEHAVIOR
T. Nakaoka, N. Touch, Y. Nagatu. and T. Hibino ... 346
NUMERICAL SIMULATION OF REGIONAL SEDIMENT TRANSPORT AND SHORELINE CHANGE AT ENSHU COAST, JAPAN
L. X. Hoan, S. Kato, A.S. Mustari and P. T. Nam ... 352
EVOLUTION CHARACTERISTICS OF NORTH BRANCH IN THE YANGTZE ESTUARY SINCE MIDDLE 20
THJ. Zheng, C. Zhang and Q. Yang ... 359
COMPLEXITIES IN COASTAL SEDIMENT TRANSPORT STUDIES BY NUMERICAL MODELING
I. Dandayudapani and M. Murali. R ... 364
BACKSHORE EROSION DUE TO HIGH SWELL WAVES
K. H. Kim and K. T. Shim ... 367
HYDRAULIC ANALYSIS OF A MANGROVE PLANTING ZONE FOR MITIGATION OF TYPHOON-INDUCED COASTAL EROSION
E.C. Cruz and J.C.E.L.Santos ... 373
THE DEVELOPMENTAL PROCESS OF FLOOD SHOALS BASED ON OBSERVATIONS IN TOUFUTSU LAKE, JAPAN
T. Horie, K. Nirei, H. Kamada, K. Yagisawa, M. Sawamoto and H. Kondou ... 379
DREDGING - HOW CAN WE MANAGE IT TO MINIMIZE IMPACTS
J. C. Savioli, M. Magalhaes, C.Pedersen, JVan Rijmenant, M.A. Oliver, C.J.Fen and C.Rocha .... 387
IMPROVEMENT OF ACCROPODE PRODUCTION PROCESS
L. Xiang-lon, L. Hai-cheng , Z. Liang and T. Qin ... 394
CALCULATION OF CUMULATIVE DAMAGE OF TETRAPOD ARMOR LAYER
K-D. Suh, M. Kim and S-W. Kim ... 397
IRREGULAR WAVE BOTTOM BOUNDARY LAYER OVER ROUGH BED
T. Rachman , Suntoyo, Juswan and Wahyuddin ... 403
MEASUREMENT OF LONG SHORE CURRENT AFTER PERMEABLE GROIN BY FLOATING OBJECT
H. Umar, N. Yuwono, R. Triatmadja and Nizam ... 409
xi PART 2
OCEAN WAVE, TIDES, STORM SURGE AND TSUNAMI
EXPERIMENT STUDY ON OVERTOPPING OF SLOPING BREAKWATER BY SWELL
C.H. Bao, Z.H. Wu, G.L Zai and L.L Ping ... 415
NUMERICAL SIMULATION OF FOCUSED WAVE IMPACT ON A 2-D FLOATING STRUCTURE
X.Z. Zhao... 420
EXPERIMENTAL STUDY ON A NEW TYPE FLOATING BREAKWATER
L.H Cheng, C.Y Fen, Y.H Li and W.Y Jiang ... 429
INCLINED BOTTOM BOUNDARY CONDITION FOR THE MILD-SLOPE EQUATION
T.H. Jung, M. Son, S. Son and H.S. Park ... 434
ANALYSIS OF WAVE PROPERTY ON TYPICAL MUDDY COAST AND
ITS EFFECT ON SEDIMENT-TAKING LIANYUNGANG (CHINA) AS EXAMPLE
Y. Fan and W. Dengting ... 438
ANALYSIS OF MULTI-LAYER SAFETY IN COUNTRIES AFFECTED BY RECENT TSUNAMIS: EMERGENCE OF A GLOBAL TSUNAMI CULTURE
M. Esteban, V. Tsimopoulou, T. Mikami, N.Y. Yun, A. Suppasri, and T. Shibayama ... 444
EXPERIMENTAL STUDY ON WAVE FORCE SPECTRUM ON RECTANGLE BRIDGE PIER
L. Haiyuan, C.Hanbao , G.Baolei and Z.Binghao ... 450
DEVELOPMENT OF DRIVING SIMULATOR FOR THE EXPERIMENT OF TSUNAMI EVACUATION USING AUTOMOBILE
Y. Maruyama and S. Sakaki ... 454
NONLINEAR EVOLUTION OF WAVE GROUPS IN DIRECTIONAL SEA
N.N. Pujianiki and W. Kioka ... 460
ELASTIC MODEL SCALE AND MATERIAL FOR UNDERWATER STRUCTURE OF CROSS-SEA BRIDGE
B.L. Geng, B.Y. Zheng , H.Q. Zhang and H.Y. Liu ... 470
FREQUENCY BANDED WAVE CHARACTERISTIC OBSERVED BY GPS BUOYS OFF THE PACIFIC COAST OF JAPAN
K. Seki, H. Kawai, K. Kawaguchi and T. Inomata ... 474
WINTERTIME EXTREME STORM WAVES IN THE EAST SEA (JAPAN SEA):
ESTIMATION OF EXTREME STORM WAVES IN THE TOYAMA BAY, JAPAN
H.S. Lee, T. Komaguchi and A. Yamamoto ... 481
xii
WINTERTIME EXTREME STORM WAVES IN THE EAST SEA (JAPAN SEA):
NUMERICAL EXPERIEMTNS OF STORM WAVE OVERTOPPING IN THE FUSHIKI PORT, THE TOYAMA BAY
H.S. Lee, T. Komaguchi and M. Hara ... 488
SURVIVAL OF SHRINES FROM THE 2011 GREAT TSUNAMI
K. Sakai, T. Uda and T. S. Nami ... 496
NUMERICAL STUDY ON RUN-UP HEIGHTS OF SOLITARY WAVE WITH HYDRODYNAMIC PRESSURE MODEL
J. W. Lee, Y.I. Moon and Y.S. Ch ... 504
TSUNAMI FORCE ON LOW BUILDING AND THE EFFECT OF SURROUNDING BUILDINGS
Benazir, R. Triatmadja, N. Yuwono, A. Nurhasanah and Kuswandi ... 509
DAMAGES CAUSED BY 3/11 GREAT EAST JAPAN EARTHQUAKE ON COASTAL DRAINAGE PUMPING STATIONS ALONG SENDAI BAY
H. Tanji, H. Kiri and T. Nakaya ... 515
MODELING TIDAL CURRENT AROUND MOKPO, THE SOUTH WESTERN COASTAL ZONE OF KOREA
M. E. Lee, N. S. Oh, G. Kim and J. W. Kang ... 521
BEHAVIOR AND HYDRAULIC PERFORMANCES OF COMPOSITE BREAKWATER UNDER HIGHER WAVE THAN DESIGN WAVE
S. Araki and H. Ogi ... 527
DEVELOPMENT OF WAVE POWER GENERATION DEVICE WITH RESONANCE CHANNELS
B.W. Lee and C. Lee ... 533
WAVE ATTENUATION OVER SEABED MUD MODELED BY A TWO-LAYERED VISCOELASTIC MODEL
Y-Z. Xia ... 538
WAVE-CURRENT FORCE ON BRIDGE FOUNDATION
J.N. Pan, D.T. Wang, X.G. Wang, F. Nie ... 549
A SENSITIVITY STUDY OF REAL TIME STORM SURGE FORECAST MODEL TO METEOROLOGICAL AND HYDRODYNAMIC FIELDS ALONG
THE SANIN COAST, JAPAN
S. Y. Kim, S. Shiozaki and Y. Matsumi ... 555
NUMERICAL ANALYSIS OF TSUNAMI-INDUCED INUNDATION BEHIND BUILDINGS ALONG COASTS
T. Nakamura, N. Mizutani, N. Hirakawa and S. Ashizawa ... 561
SEPERATION OF WIND SEA AND SWELL FROM NEARSHORE OCEAN WAVE SPECTRA
G. Kim, W. M. Jeong and S. I. Kim ... 570
xiii
REDUCTION OF TSUNAMI INUNDATION ENERGY BY THE MODIFICATION OF COASTAL TOPOGRAPHY BASED ON LOCAL WISDOM
K. Murakami and F. Usman ... 574
PHYSICAL EXPERIMENTS ON THE HYDRODYNAMIC RESPONSE OF SUBMERGED FLOATING TUNNEL AGAINST THE WAVE ACTION
S-H. Oh, W. S. Park, S-C. Jang, D. H. Kim and H. D. Ahn ... 582
HIGH WAVE HAZARDS ON A SEAWALL INFRASTRUCTURE ALONG TYPHOON-FREQUENTED MANILA BAY
E.C. Cruz, I.A.D. Inocencio and J.C.E.L.Santos ... 588
DYNAMIC CHANGES OF COASTAL MORPHOLOGY FOLLOWING THE 2011 TOHOKU TSUNAMI
Haijiang Liu ... 594
NUMERICAL STUDY ON REGULAR WAVE OVERTOPPING FLOWS OVER SEA DIKE
X.Y. Guo, B.L. Wang, and H. Liu ... 602
POST TSUNAMI FIELD SURVEY OF 1977 SUMBA EARTHQUAKE IN KUTA, CENTER OF LOMBOK, INDONESIA
A. Suroso, E. Pradjoko, T. Kusuma, I. Sofyan, A. Mawardin1, N.P.N Wadini ... 609
CONSIDERATION OF APPLICABILITY OF STOCHASTIC
TROPICAL CYCLONE MODEL FOR PROBABILITY ASSESSMENT OF STORM SURGE
S. Nakajo, N. Mori, S. Y. Kim, T. Yasuda and H. Mase ... ` 613
A NEW TREE PARAMETERIZATION APPROACH FOR MODELLING TSUNAMI ATTENUATION BY COASTAL FORESTS
S.Husrin and H.Oumeraci ... 620
ESTIMATION OF THE SEA SURFACE DRAG COEFFICIENT BASED ON WAVE DATA
M. Yokota, N. Hashimoto, M. Kodama and R. Amiya ... 629
NUMERICAL SIMULATION OF THE 1996 TOLI-TOLI TSUNAMI AND THE 2000 PELENG TSUNAMI CENTRAL OF CELEBES WITH SINGLE FAULT MODEL
S. Aswad, B. Sunardi, M. R. Budiati.K and P. S. Melani ... 634
COASTAL FLOOD RISK: INTEGRATION OF INTANGIBLE LOSSES IN FLOOD RISK ANALYSIS
D. R. Dassanayake , A. Burzel and H. Oumeraci ... 640
PREDICTION OF DESIGN WATER LEVEL DUE TO STORM SURGE AT THE SEOGWIPO COASTAL ZONE IN KOREA
M.S-Rok, Y.S-Man, K.J-whan and H.S-Jin ... 648
NUMERICAL ANALYSIS OF TSUNAMI FLOW AROUND COASTAL DYKE
T. Mikami and T. Shibayama ... 654
xiv
THE UPPER OCEAN STRUCTURE AROUND THE TYPHOON CENTER AND ITS RELATIONSHIP WITH THE TYPHOON STRENGTH: A NUMERICAL STUDY
J. Wang, J. Zhang and W. Zhang ... 660INTERNAL GENERATION OF WAVES WITH DAMPING USING EXTENDED BOUSSINESQ EQUATIONS
V. N. Vu and C. Lee ... 666
RANDOM WAVE LOADS ON A LONG DETACHED BREAKWATER CONSIDERING DIFFRACTION
C. Lee, J-S. Jung, W-S. Park and Y-S. Cho ... 671
EXPERIMENTAL STUDY OF THE FLOW VELOCITY REDUCTION BEHIND FISHING NET
C.W. Bi, G.H. Dong, Y.C. Li and Y.P. Zhao... 677
INVESTIGATION ON 2007 ABNORMAL WAVE OCCURRED AT THE WEST COAST OF KOREA
S-B. Woo, H-M. Eom and M-S. Kim ... 683
CHANGES IN TSUNAMI BEHAVIOR IN THE HARBOR ZONE DUE TO DEVELOPMENT OF WIND-WAVE BREAKWATERS
T. Kikuchi, T. Yamashita, M. Hara and T. Komaguchi ... 689
SOUTH CHINA SEA OCEAN TIDE SIMULATOR
B. H. Choi, K. O. Kim, J. H. Yuk and K. T. Jung ... 697
SWELL PREDICTION FOR THE EAST KOREAN COAST
J.H. Yuk, K.O. Kim, B.H. Choi and K.T. Jung ... 705
WAVE HINDCAST FROM INTEGRALLY COUPLED WAVE-TIDE-SURGE MODEL OF THE EAST CHINA SEA
K. O. Kim, B. H. Choi and J. H. Yuk ... 714
EMPIRICAL FORMULA FOR COMPUTING REPRESENTATIVE WAVE HEIGHTS FROM ZEROTH MOMENT OF WAVE SPECTRUM
P. Nuntakomol and W. Rattanapitikon ... 722
NUMERICAL SIMULATION OF WAVE PROPAGATION BY MODIFIED MILD-SLOPE EQUATION
H. C. Wang and Z. P. Zhou ... 730
STORM SURGE, WAVE, AND INUNDATION SIMULATION IN THE BAY 0F BENGAL
Hendri, H. S. Lee and T. Yamashita ... 738
EFFECT ON WATER MASS STRUCTURE IN WEST JAPAN BY THE 2011 TOHOKU EARTHQUAKE TSUNAMI
K. Uno and S. Nakan ... 744
xv
NUMERICAL ANALYSIS OF MOORED SHIP MOTION CONSIDERING HARBOR RESONANCE IN POHANG NEW HARBOR
M. Kwak and C. Pyun ... 750
SLIP DISTRIBUTION OF THE 2010 MENTAWAI EARTHQUAKE FROM INVERSION OF TSUNAMI WAVEFORMS AND TSUNAMI FIELD SURVEY DATA
L. Li and Z. Huang ... 758
PRESENT AND FUTURE TSUNAMI AND STORM SURGE PROTECTIONS IN TOKYO AND SAGAMI BAYS
T. Shibayama, K. Ohira and T. Takabatake ... 764
NUMERICAL SIMULATION OF NONLINEAR NEARSHORE WATER WAVE
Y-F Zhang, C-F Zhang ... 767
A NEW CONSIDERATION FOR THE COUPLED OCEAN-ACOUSTIC MODELING
Y. Peng , X. Zhang and J. Xiang ... 772PART 3
LOWLAND DEVELOPMENT
NUMERICAL SIMULATION OF DAM-BREAK GENERATED FLOW INTO A STORM-DRAIN
T.U.L. Liyanage, G.A. Kikkert and C. Shang ... 777
APPLICATION OF NEW “STRAIGHT LINE” VACUUM PRELOADING METHOD IN SOFT SOIL FOUNDATION TREATMENT
A.Z. Liang, B.F. Jianwei, C.G. Yunzeng and D.H Fengjie ... 785
FIELD EXCURSION TO ENHANCE COASTAL AND ENVIRONMENTAL
ENGINEERING CAPACITIES OF ENGINNERS IN ADMINISTRATIVE POSITIONS
S. Seino, T. Uda and Y. Ito ... 790INFLUENCE OF THE CURING METHOD ON COMPRSSIVE STRENGTH AND POROSITY OF CONCRETE MIXED WITH SEA WATER,
MARINE SAND AND FLY ASH
M.W.Tjaronge, H. Hamada, R. Irmawaty and Y. Sagawa ... 798
ANALYSING THE ACTUAL COST WORK PERFORMANCE (ACWP) IN THE EARNED VALUE CONCEPT (EVC)
H. W. Wisal ... 802
EXPERIMENTAL STUDY OF EMBANKMENT REINFORCEMENT USING CONTINUOUS SAND-CEMENT COLUMN BARRIER ON THE DEPOSITION OF SANDY CLAY
T. Harianto, L. Samang,S. H. Nur, A. Arsyad1, I. Maricar and Hairulla ... 807
xvi
A METHOD USING GRANULATED COAL ASH FOR DISPOSAL OF THE SLUDGE CARRIED BY TSUNAMI
T. Hibino, N. Touch, T. Nakaoka and Y. Nagatsu ... 814
BENDING STRENGTH ANALYSIS OF STEEL-COMPOSITE SUBMERGED FLOATING TUNNELS
T.H. Han, D. Won, S.H. Han, W.S. Park, and K.D. Yum ... 822
PALM FIBERS INFLUENCE THE COMPRESSIVE STRENGTH AND CBR ON SOIL CEMENT
P. Suroso, L. Samang, W. Tjaronge and M. Ramli ... 826
TRANSIENT RESPONSE ANALYSIS OF A SUBMERGED FLOATING TUNNEL UNDER SEISMIC AND WAVE EXCITATIONS
.H. Ko, I.S. Han, S.H. Han, W.S Park and K.S. Lee ... 831
COMPRESSIVE STRENGTH AND CHEMICAL COMPOUND OF CONCRETE MIXED WITH SEA WATER, MARINE SAND AND PORTLAND COMPOSITE CEMENT
M.W. Tjaronge, R. Irmawaty, S. A. Adisasmita, A. A. Amiruddin, and Mansyur ... 835
PRELIMINARY FEASIBILTY STUDY OF SPECIAL SEAPORT FOR IRON PLANT IN OBI ISLAND, INDONESIA
R. U. Latief, and M. A. Abdurrahman ... 839
FIRE RESISTANCE PERFORMANCE OF SUBMERGED FLOATING TUNNEL UNDER VARIOUS FIRE CONDITIONS
D.H. Won, T.H. Han, S.H. Han and W.S. Park ... 843
BIOGROUTING STABILIZATION ON MARINE SANDY CLAY SOIL
T. Harianto, S.Hamzah, S.H.Nur, M.A.Abdurrahman, R.U.Latief , I.Fadliah and A.Walenna ... 848
MICROZONATION MODEL FOR LIQUEFACTION POTENTIAL OF MAKASSAR COASTAL AREA
A. B. Muhiddin, T. Harianto, F. Syukur, and Haadymuqtadir ... 853
PART 4
MARINE RENEWABLE ENERGY
NUMERICAL SIMULATION OF PULLOUT BEHAVIOR OF EMBEDDED SUCTION ANCHORS IN CLAY
S. Na, I. Jang, M. Oh and O. Kwon ... 860
INVESTIGATION OF OCEAN WIND ESTIMATING TECHNIQUE USING WAVE DATA AND SMB METHOD
K. Watanabe and K. Nomura ... 866
xvii
DESIGN PROCEDURE AND PERFORMANCE ESTIMATION OF TIDAL CURRENT POWER SYSTEM
C-H. Jo, S-J. Hwang, J-H. Lee and K-H. Lee ... 873
COMPUTATIONAL FLUID DYNAMICS ANALYSIS OF UNDERWATER RUBBLE MOUND LEVELING EQUIPMENT AGAINST TIDAL CURRENT LOADING
I. Jang, J. H. Ko, C. Shin, I. Han and W. Kim ... 877
INVESTIGATION OF JETTING PIPING SYSTEM IN THE SPUDCAN OF WIND TURBINE INSTALLATION JACK-UP VESSEL
C-H. Jo, Y-H. Rho and D-Y. Kim ... 881
LONG-TERM STRAIN MONITORING DATA OF JACKET-TYPE OFFSHORE STRUCTURE FOR TIDAL CURRENT POWER GENERATION UNDER SEVERE TIDAL CURRENT ENVIRONMENTS
J-H. Yi, J-S. Park, J. S. Park and K-S. Lee ... 886
DEVELOPMENT OF WAVE POWER GENERATION DEVICE WITH RESONANCE CHANNELS
B. W. Lee, C. Lee ... 891
FACTORS AFFECTING THE LOW ACHIEVEMENT OF UTILIZATION EFFICIENCY OF WAVE ENERGY FOR ELECTRIC POWER PLANT WITH TAPERED
CHANNEL TECHNOLOGY
M. A. Thaha, Nizam, R. Triatmadja and A. I. Dwipuspita ... 896
NEW CONCEPT OF SOLAR- POWERED CATAMARAN FISHING VESSEL
IKAP Utama, PI Santosa, R-M Chao, A Nasiruddin ... 903
WAVE ENERGY SYSTEM USING PIEZOELECTRIC PANEL
C. Si-bum, K. Kyu-han, H. Sung-jin and H. Seok-inn ... 910
PART 5
CLIMATE CHANGE AND COASTAL ADAPTATION
ENVIRONMENTAL REFUGEE: A STUDY OF INVOLUNTARY MIGRANTS OF SUNDARBAN ISLANDS
M. K. Bera ... 916
GLOBAL WAVE CLIMATE BASED ON THE JMA/MRI-AGCM3.2 CLIMATE CHANGE PROJECTION
M. Zikra, N. Hashimoto, J. Ekstedt and M. Kodama ... 926
IMPACTS OF POTENTIAL FUTURE SEA LEVEL RISE ON THE NORTH BRANCH OF THE CHANGJIANG RIVER ESTUARY: QUANTIFYING THE SALINE /
WATER INTRUSION IN THE DRY SEASON
C. P. Kuang, W. Chen, J. Gu, X. D.Mao and H. C. Huang ... 932
xviii
REQUIREMENT IDENTIFICATION OF MARINE WEATHER SERVICES FOR COASTAL ADAPTATION
S. Mujiasih ... 938
TROPICAL COASTAL ENGINEERING IN INDONESIA ADAPTING TO NEAR-TERM OCEAN-CLIMATE CHANGES
T. Yamashita, H. Bambang, K. Teti and Hendri ... 944
RESEARCH ON SEA LEVEL RISE DUE TO GLOBAL WARMING IN THE
NORTHWESTERN PACIFIC USING A NON-BOUSSINESQ NUMERICAL MODEL
C. Lim, D-H Kim and S-B Woo ... 950MANGROVES AS A SUSTAINABLE COASTAL DEFENCE
A.L. McIvor, I. Möller, T. Spencer and M. Spalding ... 956
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Y. Okimoto, A. Nose , D. Murdiyarso, J. Purbopuspito, and S.D. Sasmito ... 964
WAVE ENERGY EVOLUTION OF YELLOW RIVER DELTA INDUCED BY CLIMATE CHANGES
W. Hongji, L. Bingchen and L. Huajun ... 969
PROBABILISTIC FLOOD MAPPING OF STORM SURGES DUE TO TROPICAL CYCLONES WITH SEA-LEVEL RISE ALONG MEKONG DELTA
H. Nobuoka, V. C. Mai and T. V. P Dang ... 973
SEA LEVEL RISING TRENDS IN THE SOUTH CHINA SEA OVER 1993-2011
C. Haoliang and P. M Rizzoli ... 979
IMPROVING THE COASTAL HAZARD MANAGEMENT IN INDONESIA: LESSON LEARNED FROM OTHER COUNTRIES
A. Y. W. Widayati and K. H. Kim ... 984
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H. Kiri, H. Tanji and T. Nakaya ... 990EXTREME WAVES GENERATED BY TYPHOON BOLAVEN(201215) IN SOUTHERN KOREAN WATERS
J. W. Chae, W. M. Jeong, K. C. Jun, J. Y. Choi, W. S. Park, and W. K. Park ... 996
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K.V. Anand, S.A. Sannasiraj and V. Sundar ... 1002
ASSESSING CLIMATE CHANGE IMPACTS BY DPSIR FRAMEWORK FOR QUANG NAM COASTAL ZONE, CENTRAL VIETNAM
P. H. Nga, K. Takara and P. T. H. Lan ... 1008
xix PART 6
MARINE ECOLOGY AND ENVIRONMENTS
A MODEL TO SIMULATE THE SPREADING OF OIL AND GAS IN UNDERWATER OIL SPILLS
X. Niu, X. Li and X. Yu ... 1014
MANGROVE CONSERVATION IN COASTAL AREAS SAMAS BEACH LAGOON FOR CONTROLLING SEA WATER ABRASION
A. P. Nurhayati, B. R. F. Raka Siwi and C. A. Muzoffar ... 1022
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H. L. Tseung and G. A. Kikkert ... 1025
COASTAL SENSITIVITY MAPPING OF GULF OF KACHCHH AND GULF OF CAMBAY, INDIA
M. Murali.R, P. Boora and Vethamony.P ... 1033
ONE DIMENSIONAL NUMERICAL MODELING OF POINT SOURCE POLLUTANT DISTRIBUTION IN ESTUARINE RIVER BASIN
H. Achiari, D. Friyadi, A.W. Pramono and B. Paramanandana ... 1036
SIMULATION OF FRESHWATER-SEAWATER INTERFACE BY EMPLOYING = CARTESIAN MESH ON THE FEM MODEL
M.Ramli ... 1043
ESTIMATION OF THE PROBABILITY DISTRIBUTION OF THE COASTAL WATER TEMPERATURE
D.H. Ko, H.Y Cho, S.H. Lee and S.T. Jeong ... 1051
PART 7
CORAL REEF PRESERVATION
EXPERIMENT STUDY ON PHYSICAL PROPERTIES AND MOTIONAL CHARACTERISTICS OF CORAL SAND
Z. Chengjie, L.U. Peidong and W. Yanhong ... 1057
GEOLOGY OF SPERMONDE PLATFORM
A. M. Imran, Kaharuddin M. S, D. A. Suriamihardja and H. Sirajuddin ... 1062
Hasanuddin University
Makassar 90245, Indonesia
Organized by :
460
Proceedings of the 7th International Conference on Asian and Pacific Coasts (APAC 2013) Bali, Indonesia, September 24-26, 2013
NONLINEAR EVOLUTION OF WAVE GROUPS IN DIRECTIONAL SEA
N.N. Pujianiki 1 and W. Kioka 2
ABSTRACT: Nonlinear wave-wave interaction behavior in deep and intermediate water depths and also on a sloping beach are investigated using third-order Zakharov equation which is known as a superior model to predict the evolution of wave group without restriction on spectra width. Transfer energy occurs between the waves components when resonant conditions satisfy. It has been found that nonlinear transfer of energy controls the shape of directional spectrum, including development of the peak and wave group evolution for wave steepness akp ≥ 0.2. The comparison of wave group evolutions on directional spectra with unidirectional spectra indicates that evolution of wave groups in deep water and at intermediate water depths are significantly affected by nonlinear interactions between directional components. When directional effect is considered, transformation of wave groups in deep water is much more pronounced at akp = 0.2. The effects of wave interaction are enhanced in relatively shallow water; however, is reduced on a sloping beach, which decreases the maximum wave height.
Keywords: Nonlinear wave, wave-wave interaction, wave groups, directional spectra.
1 Department of Civil Eng., Udayana University, Kampus Bukit, Jimbaran, Bali INDONESIA
2 Department of Civil and Environmental Eng., Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya JAPAN INTRODUCTION
Ocean waves have a complex pattern and are random in amplitude, period and direction. According to Goda (2009) although sea waves may look random, inspection of wave records indicates that high waves fall into groups rather than emerge individually. Wave grouping and associated nonlinear effects play an important role for some coastal issues such as wave overtopping, wave run-up and sedimentation. However, the number of works dealing with nonlinear aspects of directional wave group transformation is still limited.
The nonlinear interaction of gravity waves has been a subject of interest for many years. The interaction produces only a small modification to the motion in the second-order, which remains bounded in time. In the third approximation, it is possible for a transfer of energy to take place from three primary waves to a fourth wave, in such a way that the amplitude of the fourth wave increases linearly with time (Longuet-Higgins 1961).
According to Shemer et al. (2001), the third-order Zakharov equation is generally accepted as a superior model for the description of the evolution of nonlinear water waves. This equation has been examined by some investigators, for instance Kit et al. (2000), Kit and Shemer (2002), Stiassnie and Shemer (1984, 2005), Kioka et al. (2005, 2011), Janssen (2003), Janssen and Onorato (2007), Stiassnie and Gramstad (2009).
Unfortunately, the previous Zakharov models use a very narrow band and do not include the effect of directionality, which is possibly significant for wave- wave interaction. In the present study, nonlinear aspects
of directional spectra are first investigated at constant depths and on a sloping beach and then the transformation of wave groups are analyzed. The initial conditions for the numerical simulations are characterized by a Gaussian spectrum for several values of wave steepness and relative water depths. Wave group evolutions of directional spectra are compared with the results from unidirectional spectra to investigate the directional effect.
According to Shemer et al. (2001), the initial-phase in the complex wave spectra is essential in determining the eventual shape of the surface elevation variation. To eliminate the effects of initial random phases, the comparison of wave group evolutions in the current study is conducted using the same initial random phases.
To demonstrate the transformation of wave groups in nature, field observation data at Akabane beach were used. The characteristic of nonlinear spectral evolution propagating over the continental shelf toward the coastal region are investigated using the directional components from field observations, and are then related to the evolution of the amplitude.
THEORETICAL MODELS
The Third-order Zakharov Equation
The third-order Zakharov integral equation which describes slow temporal evolution of gravity waves in water of infinite depth firstly was derived by Zakharov
Nonlinear Evolution Of Wave Groups In Directional Sea
461 (1968). In order to describe the spatial evolution of gravity waves in water of infinite/finite depth, Shemer et al. (2001) have modified the third-order Zakharov model, into the form
*
1 2 3 1 2 3
1 2 3 1 2 3
1 2 3
( , , , )
( )exp ( )
g h
i B T B B B
i x
d d d
c k k k k
k k k k (1)
where B denotes the complex amplitude, * is the complex conjugate, δ is the Dirac δ-function, cg is the group velocity, ∇h is the horizontal gradient and the kernel T(k,k1,k2,k3) is given in Stiassnie and Shemer (1984) and corrected by Mase and Iwagaki (1986). This spatial Zakharov equation describes evolution of the complex amplitude B of each free wave in the spectrum due to four-wave interaction in mild slope (|∇h |≤ O(ε2)) space domain, which satisfies the near resonant condition:
2
1 2 3 0, 1 2 3 O( )
k k k k (2) where ε is a small parameter representing the magnitude of nonlinearity, and the wave vectors k, k1, k2, k3 and the frequencies ω, ω1, ω2, ω3 each satisfy the following dispersion relation, with h being the water depth:
2 g tanh h
k k (3) The mode-coupled discrete Zakharov equation can be written as
2
2
2
* ,
* , ,
( , , , )
2 ( , , , )
( , , , )
exp (2 )
( , , , )
exp ( )
j p q
j n p q
g h j j j j j j
j n j n n j
n j
j j p q j p q
p q j
j p q
j n p q n p q
n p q j
j n p q
i B T B B
T B B
T B B B
i x
T B B B
i x
k k k
k k k k
c k k k k
k k k k k k k k
k k k k k k k
k k k k
( , ,n p q1, 2,... )N (4) The set of mode-coupled nonlinear complex ordinary differential equations is solved using the fourth-order Runge-Kutta method. When calculating the kernel in Eq.
(1), we have introduced Stokes’ corrections to remove
near-resonance singularities. Nevertheless, Eq. (1) is invalid for water of very shallow depth; the equation requires that the dispersion remain sufficiently strong (see Agnon 1993). The first-order free surface elevation η(x,t) is related to the quantity B and computed through
1/ 2
( ) )
1 ( )
( , ) ( )
2 2
( , ) exp ( t
t g
B t i
x k
x k
k k
(5)
Wave Group Structure
The structure of wave groups can be quantitatively described using a wave envelope. The wave envelopes of various frequency bands can be calculated using a Hilbert transform. If the sea surface elevation η(t) is a stationary random function of time, then the Hilbert transform ξ(t) is given by
t 1 P ( )tt x
(6) where P indicates the Cauchy value. With the Hilbert transform ξ(t) of the function η(t), the analytic function is given as
exp{
}S t t i t A t i t (7) The wave envelope A(t) can then be obtained by
2
( )2 1/2A t t t , (8) The envelope A(t) is always symmetrical with respect to the t-axis, as η(t) is composed of only first-order free waves. Only the fundamental frequency band 0.5fp ~ 1.5fp, which produces free waves only and does not include the bound waves, is considered and calculated.
The amplitude Aave denotes the average value of the envelope amplitude (see Fig.1).
Fig. 1 Definition of wave group structures.
N.N. Pujianiki and W. Kioka
462 The zero-up cross method relative to Aave is used to determine the wave group period Tg. The wave group amplitudes Agmean and Agmax denote the average and maximum of the envelopes, respectively. The wave group period Tgmean is the average value of Tg and Tgmax
corresponds to the period of the wave group containing Agmax.
NUMERICAL SIMULATIONS
The wave conditions for the numerical simulation, characterized by the peak period Tp, relative water depth kph, wave amplitude a(ω,θ) and principal direction θ were defined for input in the nonlinear wave interaction modeling. The principal wave direction θ = 0 was used for all the simulations except the field data. The wave model requires initial condition information, describing the initial state of the sea. In this study, the initial sea state was described as a Gaussian spectrum in the form
0
0
2 22 2
, exp
2 2 2
m i
S
(9)
where m0 is the zero-th moment of the spectrum, ω is the angular frequency, and σω and σθ are standard deviations for frequency and direction, respectively.
By taking a finite range of frequency (ωmin,ωmax) and direction (θmax,θmin), the initial amplitude a(ω,θ) = (2S(ω,θ)dωdθ)1/2 was determined for calculating the complex amplitude B, which is obtained by
1
2 2
, exp B g a i
(10)
where ϕ is the random phase.
The wave steepness akp = 0.07 ~ 0.2 (a and kp being the carrier wave amplitude and number) were used for simulation. The relative water depths, denoted by kph, in deep water and intermediate water depth are equal to 5.0 and 1.0, respectively. Directional spectra for sloping beach cases are studied by simulated numerical calculation from intermediate through shallow water depths. For modeling the field condition, the initial condition is specified at Station A, and further, the waves propagate to Station B with distance 30Lp. The relative water depth on the sloping beach is 1.0 ≥ kph ≥ 0.5, with slope calculation kph(i) = kp (26 – 13(i/z)2), where z is the number of segments and i = 1,2,3,….z.
At intermediate water depth kph = 1.0, we are not considering the adjustment of the spectrum as the effect of water depth, as in the Wallops spectrum. We just
assume that the same shape of the Gaussian spectrum is used in deep water and at intermediate water depth.
Directional spectra were simulated with 1050 components, which consisted of 50 components of frequency and 21 directional components. Additionally, refraction effects on sloping cases were calculated based on linear theory. The directional spectra were normalized by the peak of the initial directional spectrum S0(fp,θp).
Finally, evolution of wave groups as a result of the directional spectrum was compared with unidirectional simulation, which consisted of 100 frequency components. The Runge-Kutta method, which solves a differential equation numerically, gives the integration of the spatial evolution of the nonlinear waves.
RESULTS AND DISCUSSION
Now we present the results of the simulations as well as an analysis of these results. Nonlinear wave interaction effects on the evolutions of directional spectra were analyzed to investigate the transformation of wave group structures. Attention is paid mainly to the transformation of directional spectra; then the evolution of the wave groups due to the nonlinear wave-wave interaction both for directional spectra and unidirectional spectra are compared.
Transformation of Directional Spectra
The transformations of directional spectra as the effects of wave steepness akp and water depths kph are displayed in Figs. 2 and 3. Directional spectra transformation at a constant depth shows that nonlinear wave interaction more significant influence on the relative shallow water depth than in deep water as shown in Figs. 2 and 3 at the second row respectively. For akp = 0.1, directional spectra shows very small evolution, while the evolution of directional spectra for akp = 0.2 shows a significant transformation. By increasing the wave steepness, the directional spectrum in deep water grows near the peak until x = 100Lp, increases the energy which is absorbed more from higher frequencies than lower frequencies. Directional spreading occurs near the spectra peak. However in the relative shallow water depth, evolution of directional spectrum at x = 50Lp
indicates that distribution energy occurs near the spectra peak. This energy is absorbed more from lower frequencies than from higher frequencies. Dispersion spreading reduces as the water depth reduces. On sloping beach, evolution of directional spectra at Station B indicates that the distribution of energy dominant at the middle range of frequency. Transfer energy occurs from peak frequency of the spectrum to the lower frequency and higher frequency. At the lower frequency, the energy
Nonlinear Evolution Of Wave Groups In Directional Sea
463 is received from the peak frequency and absorbed, thus down shifting the peak frequency. Regarding the influence of shoaling, the low frequency part of the spectrum is affected more significantly than the high frequency part. As the waves propagate to the coast, the directional spreading becomes narrow owing to the wave refraction effect. Energy increased at the main direction which is caused by waves that propagate perpendicular to the coast.
Wave Group Evolutions
Wave group transformations of directional spectra at a constant depth and on sloping beach are expressed in Figures 4 and 5. Wave group structures are allocated using a wave envelope. The envelopes are formed only by free waves, not including the bound waves. The initial variation of the free surface elevation at x = 0 can be compared with the surface elevation at x = 50Lp for kph = 1.0 and x = 100Lp for kph = 5.0. For sloping cases, free surface elevation at Station A as the initial condition can be compared with free surface elevation at Station B.
Evolution of wave groups for akp = 0.1 shows that the group envelopes are almost same, which indicate that nonlinear effects are weak, only minor energy transfer occurs. By increasing the wave steepness, the shape of wave groups is significantly transformed. The maximum envelope fluctuates during evolution, reached a maximum and then subsided. The results were found to agree with Yuen and Lake (1982), that the evolution may be recurring or chaotic depending on the choice of modes.
Wave group transformations for the case of unidirectional spectra are presented in Figures 6 and 7.
Wave group envelopes express that the group shape is almost the same for akp = 0.1, Fig.6 illustrates only a slight evolution of wave groups. At high steepness, the nonlinear effects are clearly pronounced and exhibit themselves in the evolution of the shape of wave groups, as shown in Fig.7. The shape of the wave groups is totally different.
0 1 2
-45 0 45
Tp f
D i r e c t i o n
Initial condition or Station A
0 1 2
-45 0 45
Tp f
D i r e c t i o n
0 1 2
-45 0 45
Tp f
D i r e c t i o n
kph = 5.0 at 50Lp kph = 1.0 at 50Lp
0 1 2
-45 0 45
Tp f
D i r e c t i o n
0 1 2
-45 0 45
Tp f
D i r e c t i o n
kph = 5.0 at 100Lp At Station B
Fig. 2 Directional spectra evolution for akp = 0.1
N.N. Pujianiki and W. Kioka
464
0 1 2
-45 0 45
Tp f
D i r e c t i o n
0 1 2
-45 0 45
Tp f
D i r e c t i o n
kph = 5.0 at 50Lp kph = 1.0 at 50Lp
0 1 2
-45 0 45
Tp f
D i r e c t i o n
0 1 2
-45 0 45
Tp f
D i r e c t i o n
kph = 5.0 at 100Lp At Station B
Fig. 3 Directional spectra evolution for akp = 0.2.
0 5 10 15 20 25 30 35 40
-5 0 5
Wave Profile
/ Aave
0 5 10 15 20 25 30 35 40
-5 0 5
Wave Envelope
t / Tp
0 5 10 15 20 25 30 35 40
-5 0 5
Wave Profile
/ Aave
0 5 10 15 20 25 30 35 40
-5 0 5
Wave Envelope
t / Tp
Initial condition or Station A
0 5 10 15 20 25 30 35 40
-5 0 5
Wave Profile
/ Aave
0 5 10 15 20 25 30 35 40
-5 0 5
Wave Envelope
t / Tp
0 5 10 15 20 25 30 35 40
-5 0 5
Wave Profile
/ Aave
0 5 10 15 20 25 30 35 40
-5 0 5
Wave Envelope
t / Tp
0 5 10 15 20 25 30 35 40
-5 0 5
Wave Profile
/ Aave
0 5 10 15 20 25 30 35 40
-5 0 5
Wave Envelope
t / Tp
0 5 10 15 20 25 30 35 40
-5 0 5
Wave Profile
/ Aave
0 5 10 15 20 25 30 35 40
-5 0
5 Wave Envelope
t / Tp
kph = 5.0 at 50Lp kph = 1.0 at 50Lp
0 5 10 15 20 25 30 35 40
-5 0 5
Wave Profile
/ Aave
0 5 10 15 20 25 30 35 40
-5 0 5
Wave Envelope
t / Tp
0 5 10 15 20 25 30 35 40
-5 0 5
Wave Profile
/ Aave
0 5 10 15 20 25 30 35 40
-5 0 5
Wave Envelope
t / Tp
0 5 10 15 20 25 30 35 40
-5 0 5
Wave Profile
/ Aave
0 5 10 15 20 25 30 35 40
-5 0 5
Wave Envelope
t / Tp
0 5 10 15 20 25 30 35 40
-5 0 5
Wave Profile
/ Aave
0 5 10 15 20 25 30 35 40
-5 0 5
Wave Envelope
t / Tp
kph = 5.0 at 100Lp At Station B
Fig. 4 Directional wave groups evolution for akp = 0.1.
Nonlinear Evolution Of Wave Groups In Directional Sea
465
0 5 10 15 20 25 30 35 40
-5 0 5
Wave Profile
/ Aave
0 5 10 15 20 25 30 35 40
-5 0 5
Wave Envelope
t / Tp
0 5 10 15 20 25 30 35 40
-5 0 5
Wave Profile
/ Aave
0 5 10 15 20 25 30 35 40
-5 0 5
Wave Envelope
t / Tp
Initial condition or Station A
0 5 10 15 20 25 30 35 40
-5 0 5
Wave Profile
/ Aave
0 5 10 15 20 25 30 35 40
-5 0 5
Wave Envelope
t / Tp
0 5 10 15 20 25 30 35 40
-5 0 5
Wave Profile
/ Aave
0 5 10 15 20 25 30 35 40
-5 0 5
Wave Envelope
t / Tp
0 5 10 15 20 25 30 35 40-5
0 5
Wave Profile
/ Aave
0 5 10 15 20 25 30 35 40
-5 0 5
Wave Envelope
t / Tp
0 5 10 15 20 25 30 35 40
-5 0 5
Wave Profile
/ Aave
0 5 10 15 20 25<
