Yasushi Takeuchi

Presenting a Model for the Revival of Rural Communities in Japan’s Disaster Zones

During our research for the Great East Japan Earthquake Recovery Assistance Project, we focused on the city of Iwanuma in Miyagi Prefecture, where we held workshops with farmers to discuss how the revival of agriculture in the area should proceed. The feedback from these workshops was subsequently reflected in our revival plan. However, scientific data on how the ground had been altered by the earthquake and tsunami was also required to hasten the area’s reconstruction and revival. To this end, we used a three-dimensional (3-D) laser measurement system with MMS (Mobile Mapping System) to reveal the changes in the topography of the survey district. Our results suggest that the MMS system can be applied across a diverse range of fields related to community development, such as improving emergency evacuation routes and road infrastructure, devising town planning models, or for agricultural production forecasting. In future, we plan to survey a wider area, and to use our findings as a baseline ground map for actual restoration work as we conduct further research into how these baseline data can be applied to community development.

TWO LAYERD BASE COURSE THICKNESS DESIGN METHOD OF CONCRETE PAVEMENT USING RELIABILITY BASED DESIGN CURVES

In the past study that a research group of Tokyo University of Agriculture, Ishikawa National College of Technology, Public Works Research Institute and Japan Cement Association carried out, design curves of the crusher-run base, the mechanical stabilized base and the cement treated base considering reliability were proposed based on bearing capacity research results of an actual size concrete pavement / base course yard constructed in the Public Works Research Institute and the past researches. However the two layered base course design method was not examined. Consequently in this study, change of bearing capacity of the two layered base course surface was examined using the Monte-Carlo simulation when the reliability level of design curves were changed, and as a result a simple reliability calculation method was proposed. 東京農業大学，石川工業高等専門学校，(独)土木研究所および(社)セメント協会の研究グループでは，土木研究所内に施工した実大コンクリート舗装および実大路盤試験区での路盤支持力測定試験結果および既往の支持力測定結果を統計分析し，信頼性分析結果に基づいて信頼度に応じたクラッシャラン，粒度調整砕石，セメント安定処理路盤の路盤厚設計曲線を提案した．しかい，2層系路盤を構築する場合についての検討は行っていない．そこで本研究では，モンテカルロシミュレーションによって信頼度が異なる路盤厚設計曲線を用いた場合の2層系路盤上での支持力がどの程度になるかを検討し，簡易な信頼度算出方法を提案した．

A STUDY ON REPAIR TARGET OF EVENESS AND BUMP HEIGHTS FOR SIDEWALK PAVEMENT

In Japan, the peoples concerns to comfortable sidewalk are becoming higher year by year. Therefore the sidewalk pavement that is considered of comfortable and scenery are developed a lot. The objectives of this study are to identify the required function of sidewalk pavement and to propose its repair target of the evenness and the bump heights. Therefore, the questionnaire was done by the road administrators about functions and management factors these are considered as important. And also the questionnaire that was answered by ordinary person (younger and elder) and wheel chair users, baby carriage users by walking on some kind of sidewalk pavement were done. As the results, the road administrator considered the bump and evenness as important factor to manage the sidewalk pavement. And the drafts of repair target for elderly person, wheel-chair user and baby carriage user and for ordinary person were proposed. 近年，歩きやすい歩道に対する意識が高くなってきており，歩行者系舗装においても歩きやすさや景観性等を重視した舗装が多種開発されている．本研究は，歩行者系舗装の利用主体別の路面要求性状を明らかにすること，路面の平たん性・段差の補修目標に関する提案等を行うことを目的とした．そこで，道路管理者に歩行者系舗装に求める性能および管理項目についてアンケート調査を行うとともに，健常者（60歳未満および60歳以上），車椅子，ベビーカーを被験者として，多様な路面を歩行することによる体感評価等を行った．その結果，歩行者系舗装の性能評価項目として，段差および平たん性が重要であることが分かった．また，健常者（60歳以上），車椅子，ベビーカーと健常者（60歳未満）を含めた路面補修の目標値を提案することができた．

RELIABILITY OF BASE-COURSE THICKNESS DESIGN CURVES FOR CONCRETE PAVEMENTS IN JAPAN

本研究では，（独）土木研究所の舗装走行実験場に施工した実大コンクリート舗装試験区，実大路盤試験区での路床，路盤の支持力調査結果および既往の研究事例に基づき，路盤厚設計曲線の信頼性に関する検討を行った．その結果，クラッシャラン，粒度調整砕石の設計曲線の信頼度はそれぞれ80％，70％であること，セメント安定処理路盤の設計曲線は路盤厚によって信頼度が異なっていることがわかった．また，これらの結果に基づき，本研究では信頼度に応じた各路盤材料の設計曲線を提案した．