記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.renene.2023.119563

researchmap

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.2208/jscejj.23-18118

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.nbsj.2023.100082

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.59490/jcrfr.2023.0002

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1080/21664250.2023.2178122

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1080/21664250.2023.2165430

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1080/21664250.2022.2161124

researchmap

記述言語：英語   出版者・発行元：IN:Coastal Disaster Surveys and Assessment for Risk Mitigation  

researchmap

記述言語：日本語  

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1007/s10346-022-01959-8

researchmap

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.2208/jscejoe.78.2_I_343

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1080/21664250.2022.2100179

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Springer Science and Business Media {LLC}  

DOI： 10.1007/s11707-021-0872-2

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Meteorological Society of Japan  

DOI： 10.2151/jmsj.2022-024

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Springer Science and Business Media {LLC}  

<jats:title>Abstract</jats:title><jats:p>This study presents a new storm surge hazard potential index (SSHPI) for estimating tropical cyclone (TC) induced peak surge levels at a coast. The SSHPI incorporates parameters that are often readily available at real-time: intensity in 10-min maximum wind speed, radius of 50-kt wind, translation speed, coastal geometry, and bathymetry information. The inclusion of translation speed and coastal geometry information lead to improvements of the SSHPI to other existing surge indices. A retrospective analysis of SSHPI using data from 1978–2019 in Japan suggests that this index captures historical events reasonably well. In particular, it explains ~ 66% of the observed variance and ~ 74% for those induced by TCs whose landfall intensity was larger than 79-kt. The performance of SSHPI is not sensitive to the type of coastal geometry (open coasts or semi-enclosed bays). Such a prediction methodology can decrease numerical computation requirements, improve public awareness of surge hazards, and may also be useful for communicating surge risk.</jats:p>

DOI： 10.1038/s41598-021-95825-7

researchmap

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Japan Society of Civil Engineers  

DOI： 10.2208/jscejoe.77.2_i_61

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Elsevier {BV}  

DOI： 10.1016/j.scitotenv.2021.148157

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Elsevier BV  

DOI： 10.1016/j.ocecoaman.2021.105753

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Elsevier {BV}  

DOI： 10.1016/j.cosust.2021.02.010

researchmap

記述言語：日本語   出版者・発行元：森北出版  

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：{MDPI} {AG}  

<jats:p>Despite all efforts and massive investments, the restoration of mangroves has not always been successful. One critical reason for this failure is the vulnerability of young mangroves, which cannot grow because of hydrodynamic disturbances in the shallow coastal water. For a comprehensive study bridging ecological and engineering principles, a portable community-based reef is proposed to shield mangroves from waves during the early stages of their growth. A series of field observations were conducted on Amami Oshima Island (Japan), to observe the growth of young mangroves and their survival rate under moderate wave conditions. The evolution of young mangroves was also observed in the laboratory under a controlled indoor environment. At the research site, it was confirmed that, after six months of germination, young mangroves could withstand normal high waves. Laboratory-grown plants were lower in height and had fewer leaves compared with the native mangroves on Amami. Based on these results, an economical reef system was designed. For this purpose, the Ahrens formula for the design of a low-crested reef breakwater was revisited. The results showed that a 50-cm-high reef constructed with 15-kg stones can protect mangroves that are a few months old and effectively promote early mangrove growth.</jats:p>

DOI： 10.3390/ijerph18020590

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.3390/jmse9010067

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.2208/jscejoe.77.2_i_925

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.2208/jscejoe.77.1_1

researchmap

記述言語：英語   出版者・発行元：CWR  

researchmap

記述言語：英語   出版者・発行元：CWR  

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Informa UK Limited  

DOI： 10.1080/03088839.2019.1634845

Scopus

researchmap

掲載種別：研究論文（学術雑誌）   出版者・発行元：Springer Science and Business Media LLC  

Abstract

Typhoon Lionrock, also known as the national number 1610 in Japan, caused severe flooding in east Japan in August 28–31, 2016, leaving a death toll of 22. With a maximum sustained wind speed of ~ 220 km/h from the Joint Typhoon Warning Center’s best track, Lionrock was classified as a category 4 hurricane in Saffir–Simpson Hurricane Wind Scale and as a typhoon in Japan Meteorological Agency’s scale. Lionrock was among unique typhoons as it started its landfall from north of Japan. Here, we studied the characteristics of this typhoon through tide gauge data analysis, field surveys and numerical modeling. Tide gauge analysis showed that the surges generated by Lionrock were in the ranges of 15–55 cm with surge duration of 0.8–3.1 days. Our field surveys revealed that the damage to coastal communities/structures was moderate although it caused severe flooding inland. We measured a maximum coastal wave runup of 4.3 m in Iwaisaki. Such a runup was smaller than that generated by other category 4 typhoons hitting Japan in the past. Our numerical model was able to reproduce the storm surge generated by the 2016 Typhoon Lionrock. This validated numerical model can be used in the future for typhoon-hazard studies along the coast of northeastern Japan. Despite relatively small surge/wave runups in coastal areas, Lionrock’s death toll was more than that of some other category 4 typhoons. We attribute this to various primary (e.g., flooding, surges, waves, strong winds) and secondary (e.g., landslides, coastal erosions, debris flows, wind-blown debris) mechanisms and their combinations and interactions that contribute to damage/death during a typhoon event.

DOI： 10.1007/s11069-020-04112-7

J-GLOBAL

researchmap

その他リンク： https://link.springer.com/article/10.1007/s11069-020-04112-7/fulltext.html

掲載種別：研究論文（学術雑誌）   出版者・発行元：Informa UK Limited  

DOI： 10.1080/21664250.2020.1780719

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1007/s11707-020-0817-1

researchmap

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.ijdrr.2020.101508

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Springer Science and Business Media LLC  

DOI： 10.1007/s11069-020-04071-z

researchmap

その他リンク： http://link.springer.com/article/10.1007/s11069-020-04071-z/fulltext.html

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1007/s11852-020-00749-5

researchmap

掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.ocecoaman.2019.104852

Scopus

researchmap

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1080/17499518.2020.1756345

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1080/21664250.2020.1738620

Web of Science

researchmap

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.2208/jscejoe.76.1_12

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.oceaneng.2020.107028

researchmap

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.uclim.2019.100506

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.rineng.2019.100067

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1080/17499518.2019.1676453

researchmap

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.2208/jscejoe.75.I_7

researchmap

記述言語：日本語   出版者・発行元：コロナ社  

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.2208/jscejoe.75.I_73

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1007/s10346-019-01166-y

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.ocecoaman.2018.10.031

Web of Science

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1080/15715124.2019.1576697

researchmap

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.2208/jscejoe.75.1

researchmap

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.2208/jscejoe.74.I_551

researchmap

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.2208/jscejoe.74.I_779

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Springer Netherlands  

DOI： 10.1007/s11069-018-3365-1

Scopus

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.apenergy.2018.04.067

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

A mangrove ecosystem is an important option in Ecosystem based Disaster Risk Reduction (Eco-DRR). The effectiveness of an artificial mangrove landfill in reducing tidal amplitudes was studied by performing a coupled numerical model that simulated wave propagation and soil consolidation. The constructed model simulated the propagation of tide over an artificial landfill that was subjected to land subsidence, sea-level rise, vegetation growth, and sediment deposition. A case study analysis confirmed that the tidal amplitudes are reduced if the initial elevation of the landfill is appropriately considered to achieve an equilibrium state of the landfill over its lifetime. Sediment deposition may be the only dependable source to sustain the surface elevation of a mangrove with relative sea-level rise. Sediment deposition is important to promote vegetation growth, which in turn contributes to sedimentation by enhancing a tranquil hydrodynamic environment. An insufficient initial elevation of the landfill will result in less effective protection against tidal propagation after it substantially subsides.

DOI： 10.3390/su10041045

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1080/17499518.2018.1465573

researchmap

記述言語：日本語   出版者・発行元：文部科学省科学技術・学術政策研究所 (NISTEP)  

DOI： 10.15108/stih.00117

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.24910/jsustain/5.2/8691

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.24910/jsustain/5.2/7785

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.3390/geosciences7040121

Web of Science

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.5194/nhess-2017-365

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1038/nclimate3344

researchmap

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.2208/jscejoe.73.35

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.ijdrr.2017.04.007

Web of Science

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Jakarta has been experiencing severe land subsidence over the last few decades. A questionnaire survey of local inhabitants revealed that seawater is already overtopping coastal dykes and flooding a vulnerable community along Jakarta’s waterfront. The present study projects coastal floods around Jakarta until the year 2050 to understand the long term effectiveness of proposed dykes under continuing rapid land subsidence scenarios. This is done through a hydrodynamic model that considers land subsidence, sea-level rise, and tides. The analysis confirms that, if high enough, coastal dykes will help to prevent flooding, though their effectiveness will eventually disappear as land subsidence continues. For example, a 3-m dyke, which is expected to be sufficiently high to cope with present-day conditions, could completely lose its ability to stop floods by the year 2040. Moreover, higher dykes can also bring about other problems, because if they are overtopped, they actually prolong flooding, essentially trapping a higher volume of water inland. On the other hand, a small 1-m dyke can be expected to stop coastal floods if land subsidence can be stopped. This study demonstrates that actions to stop land subsidence would be the most effective countermeasure to mitigate coastal floods from the middle of the 21st century onwards, emphasizing the need to prioritize such actions among the range of countermeasures being proposed for Jakarta.

DOI： 10.3390/su9040619

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.5194/nhess-2017-61

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

The authors have examined the characteristics of Typhoon Haiyan (Yolanda), which made landfall on the coast of the Philippines on November 2013, generating a substantial storm surge. In order to better understand the storm surge phenomenon, its nature and severity were analysed by means of a numerical simulation and a field survey. Unlike most other tropical cyclones that weaken before they hit land, Haiyan struck Leyte Island at near peak strength, with maximum sustained wind speeds of 160 knots, the strongest in the recorded history of the Western North Pacific. Haiyan approached very quickly with a forward speed of 41 km/h towards Leyte, which was also the fastest among typhoons with similar intensities. As a result of these extreme gusts and the exceptionally low central pressure of the typhoon (895 hPa), Haiyan caused the largest storm surge in the recorded history of the Philippines. Numerical simulations show that the maximum storm surges occurred in Leyte Island and Samar Island. A storm surge field survey conducted by the authors corroborated this, with maximum inundation height of 7 m recorded in Tacloban, located at the northern end of Leyte Gulf. The simulation results also corroborate the fact that water levels at some locations first lowered and then rapidly began to increase after an hour.

DOI： 10.1111/jfr3.12136

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.2208/jscejoe.73.I_168

researchmap

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.2208/jscejoe.73.I_48

researchmap

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

DOI： 10.1063/1.5005734

Web of Science

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.3390/su8090959

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.2495/SAFE-V6-N3-697-703

researchmap

記述言語：英語   出版者・発行元：Beacon Reports  

researchmap

記述言語：日本語  

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.uclim.2016.05.003

Web of Science

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Since the Fukushima nuclear disaster of 2011, Japan has relied on imported fossil fuels for electricity generation, but is quickly increasing its share of renewable energy sources. Recent development has been in biomass, geothermal, wind, and solar PV, though little attention has been given to the potential of marine energy resources. The present paper carries out an analysis of the economic viability of this resource using real wave and tidal current data. The results show that marine energy technologies could be cost-effective at several locations in Japan, and can pragmatically add reliable and predictable power to the energy generation mix. Deployed in straits with strong tidal flows near large population centers in western Japan, SeaGen and Verdant-type tidal turbines are shown to operate at costs far below the current price of electricity in the country. In northern Japan, the Aquabuoy, Pelamis, WaveDragon, and Guarda-type Oscillating Water Column Wave Energy Converters show costs near the current price of electricity. Even though Aquabuoy and Pelamis are now defunct, it is likely that in the future new generation wave energy converters would be able to produce electricity at even lower costs and further enhance the practicality of developing wave power in northern Japan.

Keywords
Japan; Tidal current; Wave; Cost; Electricity price; Capacity factor

Highlights
•Tidal current data and wave buoy measurements throughout Japan are utilized.
•Energy generated by tidal stream turbines and wave energy converters is calculated.
•In heavily populated western Japan, tidal stream turbines are very economical.
•In northern Japan, wave energy farms can break even without subsidies.
•Developing ocean energy resources reduces emissions and promotes energy independence.

DOI： 10.1016/j.renene.2016.06.049

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.5194/nhess-2016-128

Web of Science

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Even though the maximum wind radius (Rmax) is an important parameter in determining the intensity and size of tropical cyclones, it has been overlooked in previous storm surge studies. This study reviews the existing estimation methods for Rmax based on central pressure or maximum wind speed. These over- or underestimate Rmax because of substantial variations in the data, although an average radius can be estimated with moderate accuracy. As an alternative, we propose an Rmax estimation method based on the radius of the 50 kt wind (R50). Data obtained by a meteorological station network in the Japanese archipelago during the passage of strong typhoons, together with the JMA typhoon best track data for 1990–2013, enabled us to derive the following simple equation, Rmax  =  0.23 R50. Application to a recent strong typhoon, the 2015 Typhoon Goni, confirms that the equation provides a good estimation of Rmax, particularly when the central pressure became considerably low. Although this new method substantially improves the estimation of Rmax compared to the existing models, estimation errors are unavoidable because of fundamental uncertainties regarding the typhoon's structure or insufficient number of available typhoon data. In fact, a numerical simulation for the 2013 Typhoon Haiyan as well as 2015 Typhoon Goni demonstrates a substantial difference in the storm surge height for different Rmax. Therefore, the variability of Rmax should be taken into account in storm surge simulations (e.g., Rmax  =  0.15 R50–0.35 R50), independently of the model used, to minimize the risk of over- or underestimating storm surges. The proposed method is expected to increase the predictability of major storm surges and to contribute to disaster risk management, particularly in the western North Pacific, including countries such as Japan, China, Taiwan, the Philippines, and Vietnam.

DOI： 10.5194/nhess-16-705-2016

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.3178/hrl.10.21

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.coastaleng.2015.11.002

Web of Science

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1142/S057856341640009X

Web of Science

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1142/S0578563416400052

Web of Science

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.5194/nhessd-3-6431-2015

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1007/s11069-015-1983-4

Web of Science

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

The unusual statistical characteristics of Typhoon Haiyan were investigated using the JTWC best track data from 1945 to 2013, particularly focusing on tropical cyclones making landfall in the Philippines. Haiyan generated the strongest winds among a collection of over 400 past storms, which was 16 % greater than the second strongest typhoon on record (Typhoon Zeb in 1998). The forward speed of Haiyan was nearly twice as fast as the average speed of these weather systems and could be the fastest typhoon on record. Thus, Haiyan can be characterized as both the fastest moving and strongest typhoon measured in the area. The return period for a Haiyan-class typhoon to make landfall was estimated to be 200 years. A statistical analysis also indicated that the number of tropical cyclone making landfall around Leyte Island in the Philippines—the area most severely damaged by Haiyan—has been steadily increasing over the past 7 decades. Analysis of sea surface temperature (SST) indicates that both Haiyan and Zeb occurred during seasons that were characterized by remarkably warm SSTs over the seas surrounding the Philippines.


Keywords
Typhoon Haiyan (Yolanda) – Tropical cyclone landfalls – Philippines – Return period – Forward speed – Storm surge

DOI： 10.1007/s11069-015-1965-6

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Given the importance of ports to immediate disaster relief operations after a major tsunami, breakwaters are necessary to sustain a minimum level of functionality required to carry out port operations. However, most breakwaters that protect fishery or industrial ports are not designed to withstand a tsunami. For this reason, many of these breakwaters were destroyed by the 2011 Great East Japan Earthquake and Tsunami. However, some breakwaters withstood the tsunami, which facilitated the rapid resumption of port operations. In this study, 67 ports were investigated by using satellite images to identify the percentage of breakwaters that suffered damage due to the 2011 tsunami and how the tsunami height and breakwater width influenced the degree of breakwater damage. Because tsunami heights were not measured at the breakwaters, they were estimated by interpolating the data observed at nearby locations with a Gaussian weighting function at a reasonable accuracy. Possible drawbacks of this simplified method are also discussed because a certain degree of estimation error is inevitable. Breakwaters less than 8 m wide were quantitatively demonstrated to inevitably experience extensive damage when the tsunami height exceeded 14 m. In contrast, breakwaters that were more than 14 m wide, exposed to tsunami heights of less than 6 m, or both were not greatly damaged. An examination of the effectiveness of armor blocks also revealed that their placement could substantially reduce breakwater damage due to a tsunami. The results suggest a simplified method, particularly for assisting local fishery administrators or other authorities concerned, to practically estimate the risk of a port suffering damage because of future tsunamis. The proposed method should contribute to prioritizing the protection of ports in order of their likelihood of failure.


Keywords: Tsunami; 2011 Great East Japan Earthquake and Tsunami; caisson breakwater; breakwater damage ratio; tsunami height; breakwater width; armor blocks



Read More: http://www.worldscientific.com/doi/abs/10.1142/S0578563415500126?src=recsys

DOI： 10.1142/S0578563415500126

researchmap

記述言語：英語   出版者・発行元：Handbook of Coastal Disaster Mitigation for Engineers and Planners  

DOI： 10.1016/B978-0-12-801060-0.00019-8

researchmap

記述言語：英語   掲載種別：論文集(書籍)内論文   出版者・発行元：Elsevier Inc.  

DOI： 10.1016/B978-0-12-801060-0.00012-5

Scopus

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Handbook of Coastal Disaster Mitigation for Engineers and Planners  

Scopus

researchmap

掲載種別：研究論文（学術雑誌）   出版者・発行元：Handbook of Coastal Disaster Mitigation for Engineers and Planners  

DOI： 10.1016/B978-0-12-801060-0.00033-2

Scopus

researchmap

掲載種別：研究論文（学術雑誌）   出版者・発行元：Handbook of Coastal Disaster Mitigation for Engineers and Planners  

DOI： 10.1016/B978-0-12-801060-0.00015-0

Scopus

researchmap

掲載種別：研究論文（学術雑誌）   出版者・発行元：Handbook of Coastal Disaster Mitigation for Engineers and Planners  

Scopus

researchmap

掲載種別：研究論文（学術雑誌）   出版者・発行元：Handbook of Coastal Disaster Mitigation for Engineers and Planners  

DOI： 10.1016/B978-0-12-801060-0.00004-6

Scopus

researchmap

掲載種別：研究論文（学術雑誌）   出版者・発行元：Handbook of Coastal Disaster Mitigation for Engineers and Planners  

DOI： 10.1016/B978-0-12-801060-0.00030-7

Scopus

researchmap

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.2208/jscejoe.71.1

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Manning's n values for open channel (river) flow have been studied by hydraulic engineers since the late 19th century, and a rich literature exists on the topic including large-scale laboratory experiments and actual field measurements. Both river flood models and shallow water equation tsunami inundation models incorporate the importance of varying equivalent roughness values with the large-scale roughness elements present for different land use types. However, many tsunami models (especially in Japan) use n values based on a very limited set of small-scale model laboratory experiments with inappropriate Reynolds and Weber numbers, instead of using Manning's n values from the open channel flow literature. Due to this, equivalent Manning's n values for vegetated and urban areas in these tsunami inundation models are too small, causing the mitigating effect of forests and urban regions to be underestimated. This paper presents a review of Manning's n research applied to both river flood and tsunami inundation models, and suggests values to improve the reliability of the latter.

DOI： 10.1142/S0578563415500059

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.24910/jsustain/3.1/3745

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1007/s11069-014-1387-x

Web of Science

researchmap

掲載種別：研究論文（学術雑誌）   出版者・発行元：Handbook of Coastal Disaster Mitigation for Engineers and Planners  

DOI： 10.1016/B978-0-12-801060-0.00031-9

Scopus

researchmap

掲載種別：研究論文（学術雑誌）   出版者・発行元：Handbook of Coastal Disaster Mitigation for Engineers and Planners  

DOI： 10.1016/B978-0-12-801060-0.00018-6

Scopus

researchmap

掲載種別：研究論文（学術雑誌）   出版者・発行元：Handbook of Coastal Disaster Mitigation for Engineers and Planners  

DOI： 10.1016/B978-0-12-801060-0.00011-3

Scopus

researchmap

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：Elsevier Ltd  

DOI： 10.1016/j.proeng.2015.08.306

Scopus

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

The 2011 Great East Japan Earthquake and Tsunami caused devastation all along the coast of eastern Japan. Ishinomaki City was one of the most severely damaged municipalities, though the height of the tsunami in this city was smaller than that in Iwate and northern Miyagi. A large difference in the extent of building damage was found comparing two areas of Ishinomaki: one not protected by breakwaters, and the other behind the breakwaters of a large Fishery port. In this paper, the authors perform numerical simulations to determine whether these general breakwaters, which were designed not to block tsunamis but wind waves, reduced the tsunami's energy and contributed to a reduction in inundation of the areas behind the port. Before assessing the effectiveness of breakwaters against tsunamis, simulated inundation heights in each of these two areas were compared with heights measured by The 2011 Tohoku Earthquake Tsunami Joint Survey Group. It was found that a simulation with larger Manning's n value (n = 0.30) can evaluate inundation more precisely than when this value is small (n = 0.06), as often used by Japanese coastal engineers. Comparing the region protected by breakwaters with the unsheltered area, the results of a 2D shallow water equation model do not show a significant difference in inundation mainly because the tsunami intrudes through the openings in the breakwater and fills up the port basin with seawater in a very short time. Therefore, the effectiveness of general breakwaters in reducing tsunami impact should not be overestimated. However, a hypothetical study shows that water levels could be greatly reduced if the port were fully enclosed by breakwaters. This implies that a port could substantially reduce tsunami inundation if the breakwater openings were equipped to be closed before tsunami arrival. The authors also demonstrate that the difference in the extent of building damage in the two areas of Ishinomaki considered can be explained by the difference in drag forces due to the topography as well as the difference in land use, rather than by the presence of breakwaters.

DOI： 10.1142/S0578563414500181

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Thao N.D., Takagi H., Esteban M. (eds.) Coastal Disasters and Climate Change in Vietnam: Engineering and Planning Perspectives 1st ed.  

DOI： 10.1016/B978-0-12-800007-6.00016-2

Scopus

researchmap

記述言語：英語   出版者・発行元：Elsevier  

Coastal Disasters and Climate Change in Vietnam is the first book to focus specifically on natural hazards and climate change in Vietnam. The book examines threats such as tropical cyclones, sea-level rise, flooding, erosion, and salinity intrusion, and their respective effects on coastal structures and environments. It also looks at crucial management and mitigation efforts, including breakwater design, irrigation systems, coastal dunes and dikes, and more.

The challenges faced by this country in the future will have important regional and global repercussions; areas such as the Mekong Delta produce a significant proportion of the world's rice, and coastal impacts on this region will have far-reaching economic and public health effects. This book is an important source of information for government and local policy makers, environmental and climate scientists, and engineers.

researchmap

記述言語：日本語   出版者・発行元：土木学会  

researchmap

掲載種別：研究論文（学術雑誌）   出版者・発行元：Coastal Disasters and Climate Change in Vietnam: Engineering and Planning Perspectives  

DOI： 10.1016/B978-0-12-800007-6.00023-X

Scopus

researchmap

掲載種別：研究論文（学術雑誌）   出版者・発行元：Coastal Disasters and Climate Change in Vietnam: Engineering and Planning Perspectives  

DOI： 10.1016/B978-0-12-800007-6.00001-0

Scopus

researchmap

掲載種別：研究論文（学術雑誌）   出版者・発行元：Coastal Disasters and Climate Change in Vietnam: Engineering and Planning Perspectives  

DOI： 10.1016/B978-0-12-800007-6.00011-3

Scopus

researchmap

掲載種別：研究論文（学術雑誌）   出版者・発行元：Coastal Disasters and Climate Change in Vietnam: Engineering and Planning Perspectives  

DOI： 10.1016/B978-0-12-800007-6.00015-0

Scopus

researchmap

掲載種別：研究論文（学術雑誌）   出版者・発行元：Coastal Disasters and Climate Change in Vietnam: Engineering and Planning Perspectives  

DOI： 10.1016/B978-0-12-800007-6.00012-5

Scopus

researchmap

掲載種別：研究論文（学術雑誌）   出版者・発行元：Coastal Disasters and Climate Change in Vietnam: Engineering and Planning Perspectives  

DOI： 10.1016/B978-0-12-800007-6.00007-1

Scopus

researchmap

掲載種別：研究論文（学術雑誌）   出版者・発行元：Coastal Disasters and Climate Change in Vietnam: Engineering and Planning Perspectives  

Scopus

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

The authors propose a new method to estimate the tilting failure of caisson breakwaters, using a Monte-Carlo simulation that can quantitatively and stochastically estimate failure probability. An index, referred to as "Expected Frequency Exceeding of a Critical Load (EFEC)" that expresses the potential tilting failure probability of caisson breakwaters is proposed and adopted in this model. Application of the model to 40 breakwaters in Japan reveals that the threshold value of EFEC that specifies whether a caisson breakwater is safe or unsafe could lie in the range from 0.02 to 0.04. The authors also found that unstable caisson geometry, showing a large value in the aspect ratio of the caisson, can provide additional indication of when tilting failure is likely to occur. It is expected that the present method can provide a practical way for engineers to judge the possibility of tilting failure in caisson breakwaters.

DOI： 10.1142/S0578563413500113

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

researchmap

記述言語：日本語   出版者・発行元：朝倉書店  

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1007/s11069-013-0567-4

Web of Science

researchmap

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

Web of Science

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1142/S0578563412500222

Web of Science

Scopus

researchmap

記述言語：英語  

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1142/S057856341250012X

researchmap

記述言語：日本語  

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1142/S0578563409001941

Web of Science

researchmap

記述言語：英語   出版者・発行元：公益社団法人 土木学会  

Field surveys were performed in the Yangon River Basin to learn lessons out of severe disasters due to Cyclone Nargis. It was found that the tide due to the storm surge was up to 3-4m around 50 kilometers upstream of the river mouth of Yangon River. According to interviews with the local residents, it also appears that significant flooding took place at inland areas as a result of the upsurge through the tributaries or channels from the main river. Apart from the nvestigation, the tracks for the present and past cyclones (1945-2007) have been analyzed based on a string of best track data. The results reveal that quite a small number of cyclone (roughly 2 times on average every 10years) have hit the southern coast of Myanmar compared to the number of cyclones that hit the coast of Bangladesh, and that the route that Nargis traced is rather unique.

DOI： 10.2208/kaigan.65.1376

researchmap

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

Web of Science

researchmap

記述言語：日本語   掲載種別：学位論文（博士）  

researchmap

記述言語：日本語  

researchmap

記述言語：英語   出版者・発行元：Proceedings of Tsunami & Storm Surge Seminar in Tanzania  

researchmap

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

Web of Science

researchmap

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

Web of Science

researchmap

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

Web of Science

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/S0578-5634(00)00018-3

Scopus

researchmap

記述言語：日本語   出版者・発行元：公益社団法人 土木学会  

2013年11月にフィリピン中部を襲った台風Yolanda (Haiyan)は高潮と強風により沿岸域に甚大な被害をもたらした．本稿では，被害の大きかったレイテ島とサマル島を中心に，災害発生から約1か月後に実施した現地調査の結果を示し，今回の災害の規模と被災状況を明らかにするとともに，近年生じた他の地域における高潮災害と比較することで，今回の災害の特徴を分析した．高潮高さはレイテ湾の最奥部沿岸の広範な地域で5mを超えており，高潮高さが概ね3mを超えている地点で家屋の流失等の大きな被害が生じていた．今回の災害は，強風による被害と強風に伴う急速な変動をもつ高潮が海岸線から数百mの局所的な範囲に被害をもたらした点が特徴であった．

DOI： 10.2208/jscejoe.70.I_1212

J-GLOBAL

researchmap

記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

The catastrophic typhoon "Yolanda" on Nov. 2013 invoked storm surge in the coastal area of the Philippines. The storm surge made the coastal regions to the devastation and maximum water height reached 5m in the Tacloban area. This paper presents the comparison between storm surge simulated results from atmospheric - storm surge- wave- tide coupled model and the observation measured by The 2013 Philippines Storm Surge Joint Survey Group headed up by Prof T. Shibayama. In this study, the TC-Bogus scheme is used in order to simulate accurate typhoon. The simulated storm surge results reached almost 5m in the Tacloban area. The coupled model including TC-Bogus scheme gives accurate simulations for estimating storm surge.

DOI： 10.2208/kaigan.70.I_236

CiNii Books

J-GLOBAL

researchmap

記述言語：日本語  

J-GLOBAL

researchmap

記述言語：日本語   出版者・発行元：土木技術社  

CiNii Books

researchmap

記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

メコンデルタの洪水リスクを評価するためには，今まで十分に考慮されてこなかった潮汐の影響の理解が不可欠である．加えて，将来的な洪水リスクの議論では，海面上昇の検証が必要となる．本研究では，潮汐と海面上昇がメコンデルタ都市の洪水頻度や浸水深に及ぼす影響を検証した．メコンデルタ最大の都市Can Thoは，河口より80km内陸に位置するが，河川水位は年間を通じて潮汐の影響が支配的であり，半日周潮，日周潮および年周潮の影響が顕著である．Can Thoの川岸では，現在年間2.5%程度の時間帯で浸水が発生しており，市内の主要道路では膝上程度の浸水が発生している．海面上昇により，将来洪水頻度が増加し，現在は雨季に集中している浸水が将来的には年間を通じて発生することが定量的に示された．

DOI： 10.2208/jscejoe.69.I_988

J-GLOBAL

researchmap

記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

気候変動が現在のペースで100年にわたり継続したと仮定して，将来の気象条件下で強大化した台風が日本に来襲した場合に発生する高潮の危険性を予測し，沿岸域防護手法を提案した．東京湾を例として検討し，算出した高潮より標高の低い地域について，失われる資産額の算出を行った．また，算定した最高高潮水位を水準とした防潮堤の嵩上や新設，堤外地の地盤高の嵩上にかかる費用の算出を行った．約100年後の気象条件下で，190cmの海面上昇を考慮した場合，東京港・川崎港・横浜港には標高にしてそれぞれ4.5m・4.0m・3.9mの高潮高を推算した．これらの標高以下の地域が全て浸水したと想定すると，東京では75兆円，神奈川では4兆円を越える被害が出る．強大化した台風が防潮堤や水門の機能を停止する場合を想定して，将来的に荒川流域の高潮防護計画を確立する必要がある．算出した高潮高への対策として胸壁防潮堤の新設・堤外地の嵩上を行うと，直接的費用は東京港において約2,600億円，川崎港・横浜港において約1,200億円となる．

DOI： 10.2208/jscejoe.69.I_994

J-GLOBAL

researchmap

記述言語：日本語   出版者・発行元：土木学会  

Characteristics of the 2011 Tohoku Earthquake tsunami and resultant damage on the coast of Tokyo Bay were studied using a field survey, an analysis of observed tsunami wave profiles and numerical hindcasting using FVCOM. The tsunami was found to overflow in several fishery ports, leading to unexpectedly high inundation and runup heights of 2.84 m and 2.91 m in Funabashi Fishery Port and Shin-Futtsu Fishery Port, respectively. The observed tsunami wave profiles indicated that the tsunami wave entered the bay with a period and a maximum height of approximately 60 min and 0.9 m, respectively, and propagated along the major axis with nearly uniform height, while the wave was amplified in ports, which characteristics were successfully reproduced by numerical hindcasting.

DOI： 10.2208/kaigan.68.I_261

researchmap

記述言語：日本語  

J-GLOBAL

researchmap

記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

ベトナムは南北に長い海岸線を有し，沿岸域災害の危険性が高い国と考えられる．しかし，北部や中部と比較して，一般的に南部地域は台風や高潮災害の危険性が小さいと考えられてきた．本稿は，ベトナム南部沿岸域の災害，特に高潮脆弱性の検証を試みるものである．急成長を遂げる海岸都市において現地調査を行い，著しい海岸侵食により危険に瀕している集落や河川中洲の極めて低平な地帯に広がる集落を確認した．住民インタビューでは台風を危惧する声は皆無に近かった．一方で，過去60年間の台風経路分析より，北部や中部と比べて，台風の発生がおよそ1/2から1/3と無視できない頻度であることを示し，また50年前には1m程度の高潮が発生したことを数値解析に基づき明らかにした．これらの結果より，近年における最大クラスの台風が当該都市を襲った場合の危険性について指摘した．

DOI： 10.2208/jscejoe.68.I_888

J-GLOBAL

researchmap

記述言語：日本語   出版者・発行元：土木学会  

On March 11, 2011, a large earthquake of magnitude 9.0 took place, generating a tsunami that caused a severe damage to the east coast of Japan. To comprehensively record tsunami trace heights along the coastal region, the 2011 Tohoku Earthquake Tsunami Joint Survey Group was organized. The authors conducted field surveys as a part of this group in Miyagi, Fukushima, Ibaraki and Chiba prefectures. In this paper, the results of these surveys are reported. Inundation heights were more than 10 m in the north part of Miyagi, 5 to 10 m along the coast of Sendai Bay and around 5 m in Ibaraki and Chiba. Buildings, including reinforced concrete structures, were washed away and ships were stranded in land. Coastal structures such as dikes and coastal forests also suffered extensive damage.

DOI： 10.2208/kaigan.67.I_1301

researchmap

記述言語：日本語  

DOI： 10.2208/kaigan.67.I_1301

J-GLOBAL

researchmap

記述言語：英語   出版者・発行元：Climate Change and the Sustainable Use of Water Resources, Leal Filho, Walter (Ed.)  

DOI： 10.1007/978-3-642-22266-5_7

Scopus

researchmap

記述言語：日本語   出版者・発行元：土木学会  

CiNii Books

researchmap

記述言語：日本語   出版者・発行元：土木学会  

CiNii Books

J-GLOBAL

researchmap

記述言語：英語  

CiNii Books

researchmap

Scopus

researchmap

Scopus

researchmap

記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

This paper aims to understand the characteristics of the tsunami disaster in the Samoan Islands by analyzing the field survey data as well as numerical simulation results. The field survey was performed about one month after the disaster to clarify the tsunami wave height and to understand the reality of the disaster according to the residents. As a result, the followings are concluded. 1) Tsunami height exceeded 5m in a wide area of Upole and Tutuila Islands. 2) In areas that have a wide coral reef, people saw the wave breaking on top of it and quickly became aware of the approaching tsunami. 3) Tsunami education contributed the residents' reaction on the evacuation. 4) Social characteristics especially existence of Matai (the chief of the village) influenced the residents' decision making after the tsunami disaster.

DOI： 10.2208/kaigan.66.1376

CiNii Books

J-GLOBAL

researchmap

記述言語：日本語  

CiNii Books

researchmap

記述言語：日本語  

J-GLOBAL

researchmap

記述言語：英語  

Web of Science

Scopus

researchmap

Scopus

researchmap

記述言語：日本語   出版者・発行元：土木学会  

DOI： 10.2208/kaigan.65.1376

CiNii Books

J-GLOBAL

researchmap

記述言語：日本語   出版者・発行元：土木学会  

DOI： 10.2208/kaigan.65.891

CiNii Books

J-GLOBAL

researchmap

記述言語：日本語   出版者・発行元：土木学会  

Climate change is expected to lead to increases in both sea level and typhoon intensity. Such changes may threaten the stability of breakwaters. In this study, calculations using the SWAN model showed that a 10% increase in wind speed can lead to a 20% increase in wave height. The expected sliding distances for the breakwaters at Shibushi Ports were estimated using a probabilistic method proposed by Takagi et al. (2008). It is noteworthy that in the future sliding distances may become three times greater than current ones due to a combination of increases in sea level and wave height.

DOI： 10.2208/kaigan.65.891

researchmap

記述言語：日本語  

J-GLOBAL

researchmap

記述言語：日本語   出版者・発行元：日本沿岸域学会  

CiNii Books

J-GLOBAL

researchmap

記述言語：日本語  

J-GLOBAL

researchmap

記述言語：英語  

Web of Science

Scopus

researchmap

記述言語：英語  

Web of Science

Scopus

researchmap

記述言語：日本語   出版者・発行元：日本自然災害学会  

The cyclone &#039;Nargis&#039; hit the southern part of Myanmar on May 2^&lt;nd&gt; and 3^&lt;rd&gt; 2008. This devastating cyclone caused enormous number of casualties as well as fatal damages to houses and paddy fields, particularly both the downstream areas of the Irrawaddy and Yangon Rivers. In the present field survey, thought the activities were limited to the area near Yangon city due to certain government restrictions, it was found that the tide due to the storm surge was probably up to 3-4m around 50 kilometers upstream of the river mouth of Yangon River. According to interviews with the local residents, it also appears that significant flooding took place at inland areas as a result of the upsurge through the tributaries or channels from the main river. Even though the situation was catastrophic, it seems that most residents had not evacuated. One of the reasons for this could be related to the fact that the cyclone passed through the area investigated in the late night to the early morning of May 3^&lt;rd&gt;. Another reason might be because of an underestimation or the lack of perception of the threat of storm surge. Apart from the investigation, the tracks for the present and past cyclones (1945-

CiNii Books

researchmap

記述言語：日本語   出版者・発行元：自然災害科学会  

The cyclone 'Nargis' hit the southern part of Myanmar on May 2^<nd> and 3^<rd> 2008. This devastating cyclone caused enormous number of casualties as well as fatal damages to houses and paddy fields, particularly both the downstream areas of the Irrawaddy and Yangon Rivers. In the present field survey, thought the activities were limited to the area near Yangon city due to certain government restrictions, it was found that the tide due to the storm surge was probably up to 3-4m around 50 kilometers upstream of the river mouth of Yangon River. According to interviews with the local residents, it also appears that significant flooding took place at inland areas as a result of the upsurge through the tributaries or channels from the main river. Even though the situation was catastrophic, it seems that most residents had not evacuated. One of the reasons for this could be related to the fact that the cyclone passed through the area investigated in the late night to the early morning of May 3^<rd>. Another reason might be because of an underestimation or the lack of perception of the threat of storm surge. Apart from the investigation, the tracks for the present and past cyclones (1945-2007) have been analyzed based on a string of best track data. The results reveal that quite a small number of cyclone (roughly 2 times on average every 10 years) have hit the southern coast of Myanmar compared to the number of cyclones that hit the coast of Bangladesh, and that the route that Nargis traced is rather unique.

CiNii Books

J-GLOBAL

researchmap

記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

Abnormal tides wherein the water level remains high for a few days despite the absence of remarkable meteorological disturbances may occur due to incoming continental-shelf waves. In this study, it is assumed that the continental-shelf wave can be initiated off the Choshi coast; this wave will subsequently reach Tokyo Bay. First, the characteristics of tide anomalies are discussed on the basis of tide, wind, atmospheric pressure, and wave data obtained near Choshi. Second, several obvious cases of water-level propagation from Choshi to Tokyo Bay are collected by scrutinizing the tidal data at both stations. Finally, it is discussed how the adverse effects of abnormal tides induced by the continental-shelf waves may appear to be more serious if the sea level rise is dramatic.

DOI： 10.2208/proce1989.55.1306

CiNii Books

J-GLOBAL

researchmap

記述言語：日本語  

DOI： 10.2208/jscejb.65.246

researchmap

記述言語：日本語   出版者・発行元：土木学会  

CiNii Books

researchmap

記述言語：日本語   出版者・発行元：土木学会  

CiNii Books

J-GLOBAL

researchmap

記述言語：日本語   出版者・発行元：地盤工学会  

Japan is one often regions which are most prone to earthquakes. When we use a conventional straight bowling for a liquefaction-resistant ground injection, it is difficult to improve a ground immediately below the structure. We developed "Curve・Inducement・Drilling・method" that is a new method to improve the ground under existing structures. This report introduces a summary of the development technology and a example application of this new method.

CiNii Books

J-GLOBAL

researchmap

記述言語：日本語   出版者・発行元：社団法人地盤工学会  

Japan is one often regions which are most prone to earthquakes. When we use a conventional straight bowling for a liquefaction-resistant ground injection, it is difficult to improve a ground immediately below the structure. We developed &quot;Curve・Inducement・Drilling・method&quot; that is a new method to improve the ground under existing structures. This report introduces a summary of the development technology and a example application of this new method.

CiNii Books

researchmap

記述言語：英語  

Web of Science

Scopus

researchmap

記述言語：英語  

Web of Science

Scopus

researchmap

記述言語：英語  

CiNii Books

researchmap

記述言語：日本語  

DOI： 10.2208/proce1989.54.911

J-GLOBAL

researchmap

記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

Breaking waves on coastal structures produce impulse pressures that are high in magnitude and short in duration, compared with pressures exerted by non-breaking waves. The present study is concerned with a theoretical approach, which is based on the momentum impulse, to simulate the impact pressures on a vertical wall. The theoretical impact pressures are determined using varied velocity before impact process. The velocity field in the vicinity of structure is calculated by LES model including turbulence. The necessary coefficient λ* to evaluate impulse pressures is tentatively obtained through a comparison between the laboratory tests and the numerical results. The computational results using the coefficient obtained show time-histories of pressure with nonlinearity rather than linearity considered ever.

DOI： 10.2208/proce1989.54.811

J-GLOBAL

researchmap

記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

A study was made in order to ascertain the accuracy of the estimation of the failure probabilities by using a level III reliability based design for breakwaters. The computational model proposed here is a revised version of the model by Takagi and Shibayama (2006), adding the bearing capacity and the circular slip failure modes. To verify the accuracy of the model, a comparison is made between computational results and an actual example of breakwater failure. The massive failure of breakwaters that occurred at Hakodate-Ports in 2004 was selected as the actual case. Also, a new index "Expected Occurrence in Frequency (EOF) "in a given storm event for each failure mode is proposed in order to consider the accumulation of the failure and the overall failure of the breakwater quantitatively. As a consequence, it is shown how the accuracy of the computational results with the reliability based design is fairly good in comparison with the detailed report of the Hakodate's case. Besides, the advantage of the level III reliability based design over the allowable stress method is discussed.

DOI： 10.2208/prooe.23.835

researchmap

記述言語：日本語  

J-GLOBAL

researchmap

記述言語：日本語  

J-GLOBAL

researchmap

出版者・発行元：公益社団法人 土木学会  

The main purpose of the present study is to introduce an optimal procedure to consider the economical as well as stability aspects into the current model of the Level III reliability based design. To achieve this purpose, first the entire breakwater system composed of the upright section and the rubble mound is considered as the target domain, whereas the past studies have mainly focused on the upright section only. Secondly, two new failure modes, bearing capacity and circular slip failure, are incorporated into the previous model to evaluate the failure probabilities within the service lifetime for the entire section of a breakwater. The validity of the procedure proposed was confirmed through trial calculations. It is expected the newly proposed procedure can prevail over current design methods for breakwaters.

DOI： 10.2208/proce1989.54.911

researchmap

出版者・発行元：公益社団法人 土木学会  

Breaking waves on coastal structures produce impulse pressures that are high in magnitude and short in duration, compared with pressures exerted by non-breaking waves. The present study is concerned with a theoretical approach, which is based on the momentum impulse, to simulate the impact pressures on a vertical wall. The theoretical impact pressures are determined using varied velocity before impact process. The velocity field in the vicinity of structure is calculated by LES model including turbulence. The necessary coefficient λ* to evaluate impulse pressures is tentatively obtained through a comparison between the laboratory tests and the numerical results. The computational results using the coefficient obtained show time-histories of pressure with nonlinearity rather than linearity considered ever.

DOI： 10.2208/proce1989.54.811

researchmap

記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

海岸や海洋構造物を合理的に設計するためには，信頼性の高い推定手法を用いて波圧を推定することが重要であることは言うまでもないが，荷重と抵抗力の各変動特性を考慮した設計法である信頼性設計法が今後この分野において普及していくことを考えると，事前に適用可能な波圧推定手法の精度を定量的に評価しておく必要がある．本研究では，大水深に設置される防波堤において支配的な外力となる重複波圧に着目して，その有力な推定手法と期待される有限振幅重複波理論に基づく第4次近似解の推定精度の定量的な評価を水理模型実験の結果との比較に基づいて試みた．その結果，実験値と計算値の比は平均0.91，標準偏差0.10という変動特性値が得られ，また両者の関係性は正規分布で近似可能であることがわかった．

DOI： 10.2208/jscejb.63.291

researchmap

記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

防波堤や護岸, 海岸堤防などの波浪制御構造物が長期に渡って安定的に機能するためには, 堤体本体に加えて捨石マウンドや被覆ブロック, 根固ブロック等が長期的に安定なことが必要である. 防波堤・護岸の基部および法尻部では, 砕波に伴って顕著な乱流場が形成されるため, ブロックの飛散や洗掘, 裏埋土の吸出しといった被害がしばしば発生している. 本研究では, 3次元LESモデルを用いた数値計算を利用して, これら設置物の最適な設計を行うために必要な基礎的研究を行った. この結果, 3次元LESは防波堤や護岸の法尻部や端部において発生する有意な渦流れを再現できることがわかった.

DOI： 10.2208/proce1989.53.751

J-GLOBAL

researchmap

記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

今後の大水深地点における海域利用の促進や既設防波堤の維持補修の観点からは, 既往の性能評価手法の高度化が重要となってくる. 特に防波堤の設計において主たる外力となる波力を精度良く推定して設計に反映することは, 設計の合理化に大きく寄与するものと考えられる. 本研究では, 砕波時と非砕波時において波力とその時間変化が大きく異なることに着目して, レベル3信頼性設計法の更なる高度化を試みた. その結果, 大水深地点において波浪の砕波と非砕波を区別して設計することの重要性が明らかになった. 本提案の方法を用いることにより, 設置水深を問わずケーソン式防波堤の更なる設計合理化を図ることができる.

DOI： 10.2208/proce1989.53.901

J-GLOBAL

researchmap

記述言語：日本語  

J-GLOBAL

researchmap

記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

近年, 研究が進められている港湾構造物の信頼性設計法では, 波浪の設定精度が結果に大きな影響を与えると指摘されている. そこで, 信頼性設計への来襲波評価法として確率的台風モデルに波浪推算モデルを組み合わせた手法を構築するとともに, ケーソン防波堤の期待滑動量の評価を行った. 極値分布から年最大波を推定する従来の手法と比較した本手法の特長として, 年最大波だけでなく極大波を考慮できること, 波浪を経時的に取り扱えること, 来襲波の周期および波向の評価が可能であることが挙げられる. したがって, 本手法を用いることにより, 波高・周期・波向およびそれらの経時変化を考慮した, より合理的な港湾構造物の設計が可能となる.

DOI： 10.2208/proce1989.49.926

J-GLOBAL

researchmap

記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

DOI： 10.2208/proce1989.46.921

J-GLOBAL

researchmap

出版者・発行元：公益社団法人 土木学会  

A lateral artificial reef systems is a group of submerged, broad-crested detached breakwaters, which dissipate the incident wave energy by depth-controled breaking over the crests. A longitudinal artificial reef systems is a grope of wave heights and wave braking process through the refraction effect. Numerical of wave heights and wave-induced currents around these reef systems has been proved in good agreement with laboratory data. Performance of two systems in wave and current attenuation is compared using both laboratory data and numerical predictions.

DOI： 10.2208/prooe.13.31

researchmap

記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

A lateral artificial reef systems is a group of submerged, broad-crested detached breakwaters, which dissipate the incident wave energy by depth-controled breaking over the crests. A longitudinal artificial reef systems is a grope of wave heights and wave braking process through the refraction effect. Numerical of wave heights and wave-induced currents around these reef systems has been proved in good agreement with laboratory data. Performance of two systems in wave and current attenuation is compared using both laboratory data and numerical predictions.

DOI： 10.2208/prooe.13.31

J-GLOBAL

researchmap