Damage of stone walls of Kumamoto castle caused by the 2016 Kumamoto earthquake is investigated and the mechanisms of deformation, failure and collapse of the walls are discussed. 3-dimensional geometry of the walls were measured by 3D laser scanner and the deformation of the walls were analyzed by comparing with the previous measurement results before the earthquake and traditional shape of stone walls described in ancient documents. The profiles of the walls measured by 3D laser scanner clearly showed the unnatural shape of the stone walls. This unnatural shape of the stone walls can be observed even in the stone walls which was saved from the collapse. In the future, the evaluation of the safety/stability of the masonry walls is important for the restoration and 3D digital data obtained by 3D laser scanning technique will be useful.

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To prepare for the future catastrophic disasters in Japan, the reception of the foreign medical teams should be considered. However, in Japan, little study covered the planning method for the reception of the foreign medical teams. Therefore, this study aims to examine the application of the Project Cycle Management methods for planning the reception of the foreign medical teams. The PCM method successfully identified the necessary actions in the reception of the International Red Cross medical teams. In addition, this case study in the Philippines Red Cross presented the application of the PCM method for the planning. Given the PCM method is the standardized planning tool for the International Red Cross and other organization, the PCM method can be a proper tool in the preparation for the reception of the foreign medical teams.

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By the typhoon No.1610 disaster, Iwaizumi town, Iwate Prefecture, had suffered serious damage. In Akka district, although many houses were destroyed, the number of casualties were comparatively small. In order to reveal the cause of it, we conducted a questionnaire survey. As a result, first, IP terminals were effective for getting information related to evacuation in many districts. There was no precedent like this. However, IP terminals were not perfect. Second, call for an immediate evacuation from others and risk perception had strong effect on evacuation behavior. Finally, in Akka district, they evacuated on the basis of the geographic features. Depending on the location of the shelter, it was confirmed that the evacuation behavior was affected.

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In this paper, we have conducted participant observation and, analyzed participant utterances on three planning committees for disaster tradition policy and remains establishment in Ishinomaki City, Miyagi Prefecture. The results are summarized as follows. 1) All of three committees continued main issues during five times meetings. The issues are “basic principle”, “tradition contents” and “intermediary organization” in disaster tradition ground planning committee, “range of preservation” and “use of surrounding facilities” in disaster remain planning committee for Kadonowaki elementary school building, “location of cenotaphs and monuments” and “maintenance and security before inauguration” in disaster remain planning committee for Okawa elementary school building. 2) Almost of Kadonowaki committee participants who requested dismantle the school building have changed their mind to preservation remain after visiting relevant buildings in the city and actual remains in other past affected areas and discussion. 3) Almost of three committee members have given positive evaluation to planning process and plans based committee because of dialogue system which emphasize opinion and idea generation from all participants.

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After cyclone Aila, which caused devastation in Bangladesh in 2009, humanitarian agencies extensively supported the housing recovery with in-situ housing provisions. This research aimed to characterize the housing recovery measures adopted by the NGOs and local people in Koyra Upazila of Bangladesh after cyclone Aila and also assessed the outcome of the housing recovery. The methodology was developed to conduct the research from a perspective of peoples’ perception and expert opinion. It included focus group discussions, an expert opinion survey, and an institutional survey. The result shows that NGOs and local people adopted protective measures only for windstorm and regular tidal floods ignoring measures to ensure safety against storm surges. The result also reveals that the recovery measures for housing were short-term and low to moderately contributing to pre-disaster vulnerability reduction. The housing recovery curve constructed from peoples’ perception indicates a development inheriting pre-existing vulnerabilities. This research is critical of the present approach of in-situ housing recovery and advocates a land-use-based approach.

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Riverbank erosion is a vital issue in the management and restoration of rivers, especially in alluvial meandering channels because of their unique channel morpho-dynamics. Various countermeasures are thus implemented to minimize riverbank erosion and maintain stable channel sections of meandering channels. This study analyzes the performance of modified impermeable groynes with sloped crests as a countermeasure for bank erosion. Experiments were conducted in erodible meandering channels of two different sinuosities to evaluate the performance of the proposed countermeasures under varying sinuosity as well as analyze the overall morphological evolution of the channel. The results show that the low sinuosity (LS) channel was more prone to erosion compared to the higher sinuosity (HS) channel. Channel sinuosity also affected the overall channel morphological evolution with the LS channel showing more distinct characteristics of a meandering channel forming point bar and pool and riffle sequences. The proposed countermeasure showed slightly better performance in the case of the LS channel. Although the presence of the proposed groynes did not significantly deflect the high-velocity core towards the channel center, the velocity near the bank region was significantly reduced.

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There are two types of alluvial fans land-use such as housing and farming in Japan. In recent studies and disaster reports, housing area have been considered and numerical analysis with detail landform describing houses and roads have seemed to explain the realistic debris flow influence area. However, farming area have not been considered. Furthermore, numerical simulation is effective for considering debris flow influence area but suitable resolution landform data for both land-use is not clear. In this study, we conducted debris flow simulation using Hyper KANAKO system in farming area and in housing area with different resolution landform data. The results showed that farming area with different landform data showed less difference for outer edge of influence area. But some field area showed large flow depth and depositions. In both land-use, 1-m mesh high resolution seemed to show realistic influence area and debris flow behavior.

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On March 27, 2017, an avalanche occurred in Nasu Town, Tochigi Prefecture, killing eight people. The runout zone of the avalanche was estimated by the field investigation, but the track and the starting zone are not clear. In this research, we conducted surveys through UAV (Unmanned aerial vehicle) and SfM-MVS (Structure from Motion and Multi-view Stereo) photogrammetry to acquire avalanche data six days after the disaster. Results included an orthomosaic photo and a snow DSM (Digital surface model) (resolution 2.95 cm, root mean squared error 3.08 cm). Snow depth was estimated using the snow DSM and a DTM (Digital terrain model) taken before the disaster. There was a site where the estimated snow depth was small at the most upstream of the gully where the avalanche flowed. The UAV photograph showed crack-like textures as a kind of morphological features called covered snow microform. This may indicate a part of the starting zone. However, there is also the possibility of morphological change due to weather after the disaster.

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