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Tsunamis are a rare but devastating form of natural disaster that has been documented since early civilization. Throughout history, many major tsunamis have impacted on the world's coastlines, causing heavy loss of lives and damage to properties. While the Sumatran tsunami in December 2004 demonstrated the sheer scale of destruction, there remains little understanding of the implications such obliteration have for disaster planning and management in the construction industry. The purpose of this paper is to raise the awareness of these implications and address some of the pertinent issues.

The threat from tsunamis for an island state like Singapore cannot be ignored. A general study of tsunami dynamics is carried out and applied to model the worst scenario if tsunamis were to hit Singapore. Unique problems relating to such a scenario are subsequently highlighted to extrapolate an understanding of how the construction industry should now react even before the disaster strikes.

There appear to be some potential danger and immense uncertainties to the immediate coastline of Singapore in the event of a tsunami. Faced with these uncertainties, the local construction industry needs to recognise such challenges and develop appropriate policies and strategies way ahead to account for disaster planning and management.

While tsunami warning systems have been put in place, tsunamis cannot be stopped. The construction industry has a significant role to play in minimising destruction through appropriate building codes, materials, designs, enforcement and preventive maintenance of infrastructure.

The paper raises the issues of disaster planning and management caused by tsunamis and prompts the construction industry into taking appropriate and timely action to ward off what can be an extremely threatening event to both lives and properties.

Two disastrous Tsunamis, one on the west coast of Sumatra Island, Indonesia, in 2004 and another in North East Japan in 2011, had seriously destroyed a large number of bridges. Thus, experimental tests in a wave flume and a fluid structure interaction (FSI) analysis were constructed to gain insight into tsunami bore force on coastal bridges.

Various wave heights and shallow water were used in the experiments and computational process. A 1:40 scaled concrete bridge model was placed in mild beach profile similar to a 24 × 1.5 × 2 m wave flume for the experimental investigation. An Arbitrary Lagrange Euler formulation for the propagation of tsunami solitary and bore waves by an FSI package of LS-DYNA on high-performance computing system was used to evaluate the experimental results.

The excellent agreement between experiments and computational simulation is shown in results. The results showed that the fully coupled FSI models could capture the tsunami wave force accurately for all ranges of wave heights and shallow depths. The effects of the overturning moment, horizontal, uplift and impact forces on a pier and deck of the bridge were evaluated in this research.

Photos and videos captured during the Indian Ocean tsunami in 2004 and the 2011 Japan tsunami showed solitary tsunami waves breaking offshore, along with an extremely turbulent tsunami-induced bore propagating toward shore with significantly higher velocity. Consequently, the outcomes of this current experimental and numerical study are highly relevant to the evaluation of tsunami bore forces on the coastal, over sea or river bridges. These experiments assessed tsunami wave forces on deck pier showing the complete response of the coastal bridge over water.

The main objective of this study is to develop a tsunami emergency response plan for a coastal community by adopting a community‐based disaster preparedness approach.

A multi‐strategy research design utilizing both quantitative and qualitative methods was used. The weaknesses and strengths of the different agencies involved in responding to the 2004 tsunami disaster were identified through a focus group discussion. A survey was used to assess the preparedness of the community. Tsunami awareness and education were imparted through lectures, sermons, radio talk shows, informal briefings, workshops and printed materials. Tsunami evacuation routes, safe zones, warning protocols and evacuation plans were finalized through a consultation process with the community. A tsunami evacuation plan was verified during a table‐top exercise and was tested through a drill.

It is evident from the study that a community‐based approach (where the local community is taken as the primary focus of attention in disaster reduction) to tsunami mitigation and preparedness is viable. This process has provided an opportunity for tapping traditional organizational structures and mechanisms (including formal and informal community leaders) and capability‐building activities with the community disaster committees and volunteers.

Tsunami 2004 is the first ever tsunami disaster experienced in the country and thus the study provides significant lessons learned from the event. The community‐based approach to disaster preparedness is not the current practice in the country. Thus, the study demonstrates that the approach is a viable tool to enhance community preparedness to tsunami and other types of disasters as well.

Near-field tsunamis provide short warning periods of equal to 30 minutes, which can complicate at-risk individuals’ protective action decisions. In the face of a tsunami, people may turn to individuals such as friends, family, neighbors, or organizations such as the media to obtain warning information to help facilitate evacuation and/or to seek protection from the hazard. To characterize norms for protection action behavior during a near-field tsunami, the purpose of this paper is to explore American Samoan residents’ perceptions of four social stakeholder groups on three characteristics – tsunami knowledge, trustworthiness, and protection responsibility – regarding the September 29, 2009, Mw 8.1 earthquake and tsunami in American Samoa.

The social stakeholder groups were the respondents themselves, their peers, officials, and media. Mean ratings revealed that respondents rated themselves highest for tsunami knowledge and protection against the tsunami but rated peers highest for trustworthiness. In addition, officials had the lowest mean rankings for all three stakeholder characteristics. MANOVA analyses found that there was a statistically significant overall effect for occupation status on respondents’ perceptions of the four stakeholder groups and characteristics.

Employed respondents generally reported higher mean ratings for all stakeholder groups across the three characteristics than those that reported not having an occupation. Given the complexity of evacuation behavior, at-risk individuals may seek the assistance of other community members to support their protective action decisions.

The information gathered from this study provides local emergency managers with useful data that could support future disaster resilience efforts for tsunamis.

Following the 26 December 2004 tsunami, Planet Risk NGO took part in the international research program TSUNARISK and ATIP‐CNRS Jeune Chercheur. The aim of this paper is to encourage the development of tsunami‐resilient communities essentially through educative actions.

The tsunami risk in Indonesia was assessed by researchers. Planet Risk then used scientific findings and advice for building adapted prevention actions among Javanese populations.

Many people could have survived if they had received a basic knowledge of tsunamis. The Indonesian public as well as local authorities must be educated to face tsunami risk. To be efficient, this education must be adapted to local cultural and geographical characteristics. Collaboration between researchers and practitioners is a good means of reaching such an objective.

The paper is the result of a two‐year successful collaboration between interdisciplinary scientific teams and an NGO team. It demonstrates that an efficient prevention scheme can be implemented through this kind of collaboration. To the authors' knowledge it is the first time that such tsunami education programmes have been led in Indonesia.

To investigate whether or not people at risk from the 26 December 2004 tsunamis could have had better warning of the event.

This paper examines short‐term actions related to warning following the earthquake and long‐term actions related to setting up an Indian Ocean tsunami warning system prior to the disaster. The evidence is presented in the context of the long‐term processes needed to create and maintain successful warning systems.

The evidence shows that, based on the knowledge and procedures existing at the time, any expectation of effective warning prior to the tsunamis was unreasonable. On 26 December 2004, as much action was taken as feasible. Prior to the catastrophe, the Indian Ocean tsunami risks were acknowledged but no warning systems were implemented because other priorities were deemed to be higher.

This paper presents a snapshot of the complex issue of warning system development and implementation. Each national and regional case study deserves detailed attention. Further work would add to a more complete understanding of conditions before 26 December 2004.

This case study provides a reminder that planning for warnings must be done before extreme events, not following them. Successful warning systems require investment in a long‐term, ongoing process involving pre‐event planning, education, and awareness.

This paper provides an initial attempt at evaluating Indian Ocean tsunami warnings on 26 December 2004.

This paper aims to provide a general overview of the international Tsunami warning system mandated by the United Nations, particularly on cataloging past studies and a strategic focus in the Indian Ocean, particularly on the Bay of Bengal region.

Present research assimilates the secondary non-classified data on the Tsunami warning system installed in the Indian Ocean. Qualitative review and exploratory research methodology have been followed to provide a holistic profile of the Tsunami rarly warning system (TEWS) and its role in coastal resilience.

The study finds the need for strategic focus to expand and interlink regional early warning cooperation mechanisms and partnerships to enhance capacities through cooperation and international assistance and mobilize resources necessary to maintain the TEWS in the Indian Ocean region. The enhanced capacity of the TEWS certainly improves the resilience of Indian Ocean coastal communities and infrastructures.

The study is original research and useful for policy planning and regional cooperation on data interlinkages for effective TEWS in the Indian Ocean region.

The purpose of this paper in respect of tsunami‐affected villages in Tamil Nadu undertaken in a field trip in June 2005, and updated through online research is to first provide an overview of discrete, ongoing initiatives by different stakeholders – NGOs; Government and UNDP; Government's announcement to have a tsunami early warning system for the Indian Ocean in place by mid‐2007, paralleled by a partnership of different stakeholders to launch a pan‐India village‐info‐kiosk movement in July 2005.

The first step was to identify existing reports/programmes on disaster preparedess and mitigation, and then track the progress of the implementation of initiatives by different stakeholders. While highlighting the need for coordinated action, the author also proposed initiating a pilot project in two‐three pre‐selected village‐sites, which in turn could be upgraded to make them “Multi hazard‐ready”.

While the initiatives by different stakeholders were aimed at covering the targeted villages, as per their respective plans – there was as yet little visible attempt to privilege the tsunami‐affected villages, as was being done with their recovery efforts. Significantly, there was no mention of the proposed post tsunami Central Recovery Resource Center (CRRC) at Chennai “to meet the need for a coordinated action by all stakeholders” in the course of the discussions of early June, nor a reference to the potential for such a forum to deliberate on a coordinated Multi hazard, early warning action plan along the lines highlighted through vertical and horizontal linkages.

While the above activities were not part of a grand design – conceptualized, implemented and overseen by an over arching coordinating agency, nevertheless, together they add up to a broad based comprehensive DM resource base/infrastructure upon which hopefully an agency like the INCOIS in coordination with different stakeholders – possibly under the aegis of the Chennai CRRC – could build up its mandated tsunami – multi hazard – early warning system and its dissemination to the village‐level in TN.

The paper serves as a “one window resource guide” to provide at least the contours of a road map pointing to one of the few possible ways on how to go about a risk management plan in a coordinated and focused mode.

This study aims to assess and evaluate the disaster management system in Sri Lanka and the capacity of a local community to respond to natural disasters, and to propose a strategy for the dissemination of tsunami knowledge while raising public awareness of tsunami disasters.

The survey focused on three clusters of respondents and different methodologies were adopted to collect data from each group, as follows: residents: questionnaires followed by a structured interview; school children: questionnaires completed under the guidance of a teacher; government officials: questionnaires completed independently by respondents, and followed up with unstructured interviews with officials in charge of disaster related activities.

The results of the survey of residents indicate that; more than 90 percent of residents lacked tsunami knowledge prior to the 2004 tsunami; the main source of information during the disaster was direct information from family and neighbors; school education is important for raising awareness of disaster reduction; and an early warning system is a key requirement for reducing damage in the future. The school surveys reveal that; about 30 percent of school children do not yet understand what causes a tsunami; 90 percent of school children have a keen interest in studying natural disasters; comprehensive disaster education has not been provided; and audio‐visual means are thought to be the most effective tool for disaster education. The survey of officials shows that; seminars and drills on natural disaster have not thus far been conducted among general officials other than the military and police; measures need to be developed to safeguard the interests of tourists; and sirens, TV, and radio broadcasts are effective tools for disseminating disaster warnings to residents.

Based on the findings of the questionnaire and interview surveys, the following recommendations are proposed for disseminating knowledge and raising public awareness of tsunami disasters: promote disaster education at the school level; implement community‐level public awareness programs; enhance information management systems; and improve coordination mechanisms within the disaster management system.

At present, this is the only study being conducted whose goal is to quantitatively evaluate public awareness of natural disasters and disaster management in Sri Lanka.

This paper aims to describe a multi-scenario assessment of the seismogenic tsunami hazard for Bangladesh from active subduction zones in the Indian Ocean region. Two segments of the Sunda arc, namely, Andaman and Arakan, appear to pose a tsunamigenic seismic threat to Bangladesh.

High-resolution numerical simulations of tsunami propagation toward the coast of Bangladesh have been carried out for eight plausible seismic scenarios in Andaman and Arakan subduction zones. The numerical results have been analyzed to obtain the spatial variation of the maximum tsunami amplitudes as well as tsunami arrival times for the entire coastline of Bangladesh.

The results suggest that the tsunami heights are amplified on either side of the axis of the submarine canyon which approaches the nearshore sea off Barisal in the seaboard off Sundarban–Barisal–Sandwip. Moreover, the computed tsunami amplitudes are comparatively higher north of the latitude 21.5o in the Teknaf–Chittagong coastline. The calculated arrival times indicate that the tsunami waves reach the western half of the Sundarban–Barisal–Sandwip coastline sooner, while shallow water off the eastern half results in a longer arrival time for that part of the coastline, in the event of an earthquake in the Andaman seismic zone. On the other hand, most parts of the Chittagong–Teknaf coastline would receive tsunami waves almost immediately after an earthquake in the northern segment of the Arakan seismic zone.

The present assessment includes probabilistic measures of the tsunami hazard by incorporating several probable seismic scenarios corresponding to recurrence intervals ranging from 25 years to over 1,000 years.