＜抄録＞　自動運転の早期実用化には、インフラの支援が必要である。国総研では、自動車と道路が連携してよりよい道路交通の実現するため、協調ITS官民共同研究を行っており、その中で作成したインフラの支援（合流支援サービスと先読み情報提供）の仕様等の概要、同サービスの公道実証実験及びシステムのプロトタイプの概要と今後の検証内容について報告する。
To accelerate the deployment of automated driving, infrastructure to support automated driving is essential. The National Institute for Land and Infrastructure Management of Japan has been conducting joint research on C-ITS with the private sector to improve road traffic by developing a system to facilitate information exchange between vehicles and roads. In the research, we created the specifications of infrastructural support (delivery of merging assistance and look-ahead information) and conducted field operation tests for the merging assistance on public roads. This report outlines the specifications, experiments and the prototype of the C-ITS system, as well as plans of study.

＜抄録＞　前回1964年の東京オリンピックの時代、都市は著しい水質汚濁に喘いでいた。その後、下水道整備の進捗とともに都市の水環境は劇的に改善し、今では環境面のみならず街の賑わいや都市の活力をも生み出す基盤にもなっている。本稿では、東京2020大会に向けて更なる対策を加速させる東京都下水道局の取り組み等を通じて、こうした都市の活動・活力を支えている下水道の役割を紹介する。
Around 1964, when the last Tokyo Olympics was held, cities in Japan were suffering from severe water pollution. Since then, the urban water environment has improved dramatically as sewers have been installed in more urban areas. Today, they are essential infrastructure not only to protect the environment but also to generate liveliness in cities. This report describes the roles of sewers underlying urban activity and vitality while explaining related efforts by the Bureau of Sewerage of the Tokyo Metropolitan Government towards the 2020 Olympic Games.

＜抄録＞　大都市のヒートアイランド現象への対策として、路面温度の上昇を抑制する遮熱性舗装の整備が進められている一方、太陽光の反射による人体への影響を指摘する声もある。本報文では、遮熱性舗装の反射特性や気温等の周辺環境、人体への影響に関する検討結果について、最新の測定データ等を交えてとりまとめ紹介する。
To manage the heat island phenomenon in urban areas, heat-shield pavement has been introduced to prevent the temperature increase of road surfaces. However, some experts have pointed out the adverse effect of reflected sunlight on the human body. In this report, we summarize and introduce studies of the reflection characteristics of heat shield pavement, the surrounding environment on the pavement, and the effect of reflected sunlight on the human body, with the latest measurement data.

＜抄録＞　河川の水辺利用を促進するために取り組んでいる国土交通省の施策、東京における水辺を活かした都市再生の事例を紹介する。また、これまでの研究成果から、まちづくりに水辺を組み込むためのポイントを提示する。さらに、関東地整が取り組んでいるミズベリング勉強会を紹介する。
In this report, we outline projects led by the Ministry of Land, Infrastructure, Transport and Tourism of Japan to promote the use of riverfront spaces, as well as existing cases of urban regeneration in Tokyo utilizing riverfront. We also present key considerations to take into account when urban development projects are planned to incorporate riverfront spaces. The report also includes a unique effort, named the “Mizubering ”meeting(considering the possibility of utilizing riverfront), by the Kanto Regional Development Bureau.

＜抄録＞　多摩川河口域は、羽田空港跡地まちづくり整備に併せて、治水上安全な高潮堤防の整備と利用者にとって親しみのある環境を配慮した河川整備が必要である。新たなまちづくり整備と河川整備によって、より一層の水辺のにぎわいを創出し、多摩川と河口域の魅力を向上させる。
Urban redevelopment projects are planned for the Tama River estuary, where Haneda Airport was located before. The implementation of the plans requires building seawalls to protect the area from storm surges and conducting river maintenance to make the river friendlier to both visitors and the environment. Through these projects, the Tama River and its estuary will attract more people and become a lively waterfront.

＜抄録＞　横浜北西線は東名高速道路と第三京浜道路を結ぶ延長約7.1kmの自動車専用道路である。そのうち約4.1kmがトンネル構造となっている。本稿は「東京2020オリンピック・パラリンピック」開催を控える2020年3月に開通する予定の横浜北西線の概要及びその大部分を占める地下構造部の紹介である。
The Yokohama Northwest Route is under construction to be a 7.1-km highway with a 4.1-km tunnel, connecting Tomei Expressway and Daisan-Keihin Road. The route is scheduled to be put in service in March 2020 before the Tokyo Olympics in July 2020. In this report, we provide an overview of the Yokohama Northwest Route and a detailed description of the tunnel, which will be a large section of the route.

＜抄録＞　歩車が混在する狭幅員道路での歩行者の安心感・安全性を確保するための手法として路面構造に着目し、VRによる通行体験を行い、安心感・安全性に寄与する路面構造を調査した。その結果、安心感は路面を工夫することで向上し、特に色分けした路面にすることでより向上した。また、安全性については明確な変化は見られなかった。
In this study, focusing on road surface patterns as a means to ensure the physical and psychological safety of pedestrians on narrow residential roads, we investigated what types of road surface pattern serve such purposes by having pedestrians walk virtually on a narrow road using VR technology. The study found that they were able to feel safer when some modifications were made to the road surface pattern for pedestrians, and particularly so when the surface was color-coded. However, the study could not confirm whether road-surface pattern improvements may increase the physical safety of pedestrians.

＜抄録＞　浸透性コンクリート保護材の劣化因子の浸入抑制効果の確認を目的に、保護材を塗布したコンクリート試験体を用い2014年の開始から現在に至るまで暴露試験を実施している。本報告は5ヶ年目までに得られた塩化物イオン浸透深さ・濃度および中性化深さの値を元に、保護材の効果についてまとめたものである。
To study permeable material for concrete for its surface protection effect, which is considered as closely related to concrete deterioration, an exposure test has been underway since 2014, using concrete specimens to whose surfaces a silane-type surface penetrant is applied. This report summarizes the protective effect of the penetrant based on the analyses of the test results collected by the fifth year, such as the permeation depth and concentration of chloride ion and the depth of carbonation.

＜抄録＞　人工衛星からの降雨観測、降雨流出氾濫モデリング、アンサンブル降雨予測、等の最新技術を統合し、データの乏しい発展途上国を含めて適用可能な洪水予警報システムのためのプロトタイプを開発した。スリランカ国・カルー川での初期検証事例を通して紹介する。
We have developed a prototype of a flood forecasting and warning system applicable to various areas, including those in data-deficient developing countries, by integrating the latest technologies such as satellite-based rainfall observation, rainfall-runoff-inundation modeling, and ensemble rainfall forecasting. In this report, we present the results of the verification tests in which the developed system was experimentally applied to the Kalu River in Sri Lanka.

＜抄録＞　気候変動により洪水外力が増大した場合、河川流域での洪水・氾濫リスクが高まる。それにより当該流域の内外における産業経済活動にも被害が及ぶリスクが高まる。土木研究所ICHARMでは、気候変動下における降雨量変化予測と降雨流出氾濫モデルの技術開発成果に、被害特性曲線を組み合わせることでまずは農業リスクの変化予測を行う研究を行っている。フィリピンの米作地帯での研究事例を紹介する。
If flood hazards become more intense due to climate change, flood and inundation risks in river basins are likely to increase. Consequently, anticipated is a higher risk that industrial and economic activities may be affected both inside and outside the basin. ICHARM has been studying how to predict changes in industrial and economic risks, first focusing on agricultural risk, using a rice damage curve with technologies ICHARM developed to predict rainfall changes due to climate change and model rainfall, runoff and inundation processes. This article presents a case of agricultural risk assessment performed for a rice-producing area in the Philippines.

＜抄録＞　円滑な災害対応を行うには、過去の災害の教訓から学び、起こり得る困難をあらかじめ予測して必要な事前対策を講ずる必要がある。本研究では、災害対応担当者が「困る・焦る・戸惑う・迷う・悩む」などの状況に陥って、円滑な災害対応に支障をきたした状況を「災害対応ヒヤリ・ハット事例」として新たに定義し、過去の災害対応検証報告書から事例を抽出して、「水害対応ヒヤリ・ハット事例集（地方自治体編）」を作成した。
To achieve timely disaster response, it is critically important to learn lessons from past disasters, predict possible problems we may face in future disasters, and take necessary measures to prevent them. In this study, we collected cases from past disaster response reports in which disaster management personnel experienced difficulties, troubles, confusions, frustrations, etc. that interfered with timely disaster response. Defining such cases as “tense moments,” we developed a “Collection of Tense Moments during Flood Disaster Response” experienced by those in charge of disaster management in local governments.

＜抄録＞　複数の関係機関が協働する国際洪水イニシアティブが各国において推進している「水のレジリエンスと災害に関するプラットフォーム」について、活動の目的と概要を報告するとともに、水災害リスク軽減のための具体的な取り組みについてフィリピンの事例をもとに報告する。
This report describes the purposes and outline of the Platform on Water Resilience and Disasters, a project promoted in countries around the world by the International Flood Initiative, which is a global effort jointly operated by multiple international organizations. The report also explains specific plans for flood risk reduction by taking the case of the Philippines as an example.

＜抄録＞　水災害リスク低減のためには技術、それを担う人材、関係者の連携が必要でありICHARMでは、政策研究大学院大学(GRIPS)と連携し修士・博士課程のコースを設け運営してきた。送り出した修了生は帰国後各国で活躍し、研究成果が現地プロジェクトに直接貢献する事例も出てきている。その概要と成果を報告する。
Effective reduction of water-related disaster risks requires technology, experts, and cooperation among those involved. In this recognition, ICHARM has established and managed a master’s and a doctoral program in disaster management in collaboration with the National Graduate Institute for Policy Studies (GRIPS). Graduates have actively engaged in various projects back home, and there are even some cases where local projects have been developed primarily based on their graduation research. In this report, we outline the programs and achievements made so far.

＜抄録＞　大和川流域では、国土交通省近畿地方整備局、奈良県、流域市町村が連携して総合治水対策に取り組んでいる。本稿では、「大和川流域における総合治水の推進に関する条例」を制定し、ながす対策、ためる対策、ひかえる対策の3つの対策を柱とした奈良県の取り組みについて報告する。
In the Yamato River basin of western Japan, the Kinki Regional Development Bureau of the Ministry of Land, Infrastructure, Transport and Tourism, Nara Prefecture, and municipalities in the basin have been cooperative in strengthening comprehensive flood control. Nara Prefecture has recently adopted an ordinance concerning the further promotion of comprehensive flood control in the Yamato River basin, under which the prefecture plans to enhance flood control through three principal approaches: improving rivers for safely discharging floodwaters, building reservoirs for temporarily storing rainwater, and controlling unplanned urbanization for not creating flood-prone areas. This report presents the prefecture’s efforts to implement such measures.

＜抄録＞　ミャンマーの主要河川の一つであるシッタン川河口域のエスチュアリーでは激しい河岸侵食が生じ、河岸線の後退による集落や農地の消滅が深刻な問題となっている。本稿では、河岸侵食現象の実態解明を目的に、土木研究所ICHARMが現地政府と連携しながら実施してきた現地調査、及び研究活動について報告する。
Dynamic bank erosion has been observed in the estuary of the Sittaung River, one of the major rivers in Myanmar, causing very serious problems of settlements and farmland disappearing as the river line retreats inland. A team of ICHARM researchers has conducted field investigations and research in collaboration with the local government to understand the mechanism of the bank erosion in the area. We present our efforts in this report.

＜抄録＞　近年の新技術を用いた観測手法の発達は目覚ましく、河川水流量ばかりではなく流砂の水理の理解に関しても貢献している。本稿ではこれまで著者らが執筆してきた複数の論文をレビューする形式で、最新技術を用いた流砂の水理学に関する検討の一例を紹介する。またこのような技術は河床変動計算の検証や河道内の土砂通過量を検討するための技術となることが期待される。
Thanks to newly emerging technologies, river observation methods have progressed remarkably in recent years, contributing to a better understanding of the hydraulics of both water flow and sediment transport rate. In this report, we provide an overview of research on the hydraulics of sediment transport rate using the latest technologies by reviewing several papers we have so far published. The technologies introduced in this report are expected to verify the results of a numerical simulation, or to measure the sediment transport rate in an actual river.

＜抄録＞　冬期道路の立ち往生車の発生に関し、現場ヒアリング等をもとに特徴を把握して原因や課題等を整理している。これらの整理結果や現場との対話を通して、道路構造上の工夫により課題解決する方向性をまとめることを目指している。本稿では、2018年度に実施した立ち往生の発生傾向と予防的対策の内容についてまとめた結果を報告する。
We have been sorting out causes and issues regarding vehicles stuck on winter roads by analyzing the characteristics of stuck-vehicle cases based on field interviews in the hope of finding ways to prevent such accidents by improving road structures. In this report, we summarize our 2018 study on the trend of stuck-vehicle cases and preventive measures.

＜抄録＞　国土技術政策総合研究所で開発中の、ETC2.0プローブ情報を活用したボトルネック指数による渋滞発生箇所の把握手法について概要を紹介するとともに、一般道路や高速道路を対象にケーススタディを行い、手法の有効性検証を行った結果を報告する。
The National Institute for Land and Infrastructure Management of Japan is developing a new approach to locate traffic jams in real time using bottleneck points calculated based on ETC 2.0 probe data. This report outlines the new approach and presents the results of verification tests conducted for its validity when it was applied to regular roads and expressways.

＜抄録＞　国土交通省では、ICT活用のため、河川浚渫工事の出来形管理へ新たに音響測深機器及び施工履歴データを利用した「面管理」を導入の上、各種基準類を整備したが、実際にICTを活用した工事現場において基準類の適用性検証を行うとともに、検証結果を踏まえた課題を整理した。
The Ministry of Land, Infrastructure, Transport and Tourism of Japan has introduced the new concept of “area as-built management” to promote as-built management in ICT-based river dredging work using acoustic sounding equipment and construction history data and prepared criteria necessary for carrying out projects based on the new approach. In this study, we tested the criteria at ICT-driven construction sites to assess their applicability and sorted out issues from the test results.

＜抄録＞　近年頻発する大規模出水により堤防が破堤することによる氾濫流が発生している。このような流れの量を把握するための最大の課題は破堤幅・水深が時々刻々と変化することである。そのためにUAVの適切なオペレーションによる計測断面の設定、時々刻々と変化する水深の推定を考慮する計測手法を提案した。また、それら推定値に対する精度検証を行った。
In recent years, floods of large scale have occurred frequently, breaching levees and sending floodwaters inland. The biggest challenge in estimating the flood flow discharge in such a case is that the breach width and the water depth change every moment. To address this issue, we have proposed a method to determine the measurement section through the proper operation of a UAV and a method to measure the flood flow discharge by estimating the fast-changing water depth. The measurement results have been tested for accuracy.

＜抄録＞　本論文では、河川堤防の浸透の安全性評価に適用することを念頭に、現在、安全性評価で一般的に用いられている浸透流解析を用いたパイピング進行性評価手法を提案した。提案した手法を用いて、パイピングが停止した堤防模型実験の再現解析を行うことで、パイピング進行性評価手法の適用性について検討を行った。
In this study, we proposed a piping progress evaluation method using seepage analysis widely employed in safety evaluation today, hoping that the method will also be applicable to seepage safety evaluation for river levees. We examined the applicability of the proposed method for that purpose by reproducing the levee model experiment assuming that piping in the levee had stopped.

＜抄録＞　本研究では、軟弱粘性土地盤上に設置された既設道路橋の耐震性を合理的に評価するため、橋台を対象とした動的遠心模型実験を実施した。本報では、実施した一連の動的遠心模型実験のうち、粘性土層の材料と層厚を変化させた3ケースの実験結果を用いて既設橋台の地震時挙動を報告する。
In this study, we conducted a series of dynamic centrifuge model tests for bridge abutments to numerically evaluate the seismic performance of existing road bridges built on soft clay ground. In this report, we explain the behavior of the bridge abutment during an earthquake, based on the results of three tests in which different materials and layer thicknesses were applied to the clay layer.

＜抄録＞　松本砂防事務所管内は荒廃渓流を多数抱えており、豪雨時には土砂・洪水氾濫による被害が懸念されている。そこで姫川流域ならびに信濃川上流域で過去に発生した主な土砂・洪水氾濫による被害とその要因を紹介するとともに、当事務所が進めている土砂・洪水氾濫対策について紹介する。
There are many torrential streams in the area managed by the Matsumoto Erosion Control Office, and they pose a serious threat to the area as potential causes of sediment and flood disasters with substantial damage in case of a heavy rain event. In this report, we describe cases of past sediment and flood disasters in the Hime and upper Shinano river basins along with resulting damage and contributing factors. We also explain sediment and flood control measures currently being implemented by the Matsumoto Erosion Control Office.

＜抄録＞　魚野川流域は2,000m級の山々に囲まれ、急峻な河床勾配を有する支川と脆弱な地質により構成される。過去幾度となく、水害・土砂災害に悩まされてきたが、砂防堰堤や床固工の整備等砂防事業の進捗とも相まって、地域の発展を遂げてきた。現在も引き続き、土砂・洪水氾濫対策も主眼に入れて事業を実施している。
The Uono River basin is surrounded by over 2,000-meter-high mountains and characterized by very steep tributaries and weak geology. Despite severe damage from flood and sediment disasters that repeatedly occurred in the past, the basin has continued being urbanized thanks to steady progress in erosion control projects such as building erosion control dams and applying groundsill work. In recent years, too, various projects have been carried out in the basin, including the implementation of sediment and flood disaster control measures as one of the primary focuses of the basin’s disaster management.

＜抄録＞　発災から約9年が経過した東日本大震災の被災地では、震災の実情や教訓を次世代に語り継ぐ「震災伝承」の取り組みが各地で進められている。国と4県1市（青森県、岩手県、宮城県、福島県、仙台市）では、震災伝承ネットワーク協議会を立ち上げ、この取り組みをネットワーク化し目的に応じて教訓を巡り学べる仕組みをつくり始めている。災害への備えを実体験として学べる機会を提供することで、各地の防災力向上につながることが期待される。近年、自然災害が頻発化、激甚化する中、国民一人一人が災害リスクと対処について理解する「防災意識社会」への転換へ向けた先駆的な取り組みについて紹介する。
In the areas affected by the Great East Japan Earthquake about nine years ago, efforts have been made to pass on disaster experiences and lessons learned to the next generation. Aomori, Iwate, Miyagi, and Fukushima prefectures and Sendai City have jointly established the Disaster Memorial Network Concil and started building an information network of their efforts for people to have easy access to and learn lessons according to their needs and purposes. They are hoping that people will be able to contribute to improving disaster preparedness in their communities by learning how to prepare for disasters through the collected experiences and lessons. This report explains a pioneering initiative to transform the society into a one prepared for disasters, in which each person knows how to manage disaster risks, in order to address natural disasters that have been increasingly frequent and intense in recent years.

＜抄録＞　UAV等の点検ロボットを活用した橋梁点検の「現地点検作業」と「点検記録作成作業」の効率化を目的として、その際の課題となる"膨大な画像の管理"、"画像判読による損傷識別"、"損傷位置の正確な記録"に対応するべく、Structure from motion（SfM）より生成する橋梁の3次元データ精度の基礎検証と3次元データを活用した画像管理方法について報告する。
To further promote bridge inspection using robots such as UAV, we have been improving efficiency in on-site inspection and the documentation of inspection results. The current challenges in this effort are the management of a vast number of images, image analysis and damage detection, and the accurate recording of damage locations. In this report, we present the results of the accuracy test of 3D bridge data generated by Structure from Motion (SfM) and explain the management of images using 3D data.

＜抄録＞　RC床版では、車両走行時の輪荷重による疲労等の複合作用によって、床版上面の土砂化が発生し、最終的には抜け落ちに至る場合がある。RC床版の劣化を著しく進行させる滞水を検出することが有効になると考えられ、非破壊技術の一つである電磁波レーダにより床版上面の滞水について検知する手法の検討を実施している。
Cases have been reported in which RC slabs deteriorate in their surface under the combined impact caused by various factors such as fatigue attributed to the wheel load from traveling vehicles and eventually fall off. Since stagnant water on RC slabs can accelerate slab deterioration, we have been studying a new approach to detecting it using electromagnetic wave radars, one of the non-destructive testing technologies.

＜抄録＞　UAVを用いた人工リーフの簡易な点検方法として、撮影した画像の補正、三次元形状復元計算、異常値の除去、真の水深の推定という手順で水面での屈折の影響を補正する方法を提案し、人工リーフの三次元形状を推定できることを示した。
In this research, we proposed a simple method using UAVs to accurately capture the three-dimensional shape of artificial reefs by minimizing the effect of refraction in the water surface through the correction of photographed images, three-dimensional shape restoration calculation, the removal of abnormal values, and the estimation of true water depth. We tested the method and verified its capability for the purpose.

＜抄録＞　次世代シーケンサーを用いたDNA塩基配列に基づく動植物プランクトンモニタリング解析手法の確立に取り組み、ダム貯水池水質の維持管理に有効な手法の開発を目指す。今回は、ダム貯水池に含まれる細菌および動植物プランクトンについて、次世代シーケンサーおよび光学顕微鏡による同定結果の比較について報告する。
We have been working on the development of DNA-based monitoring and analysis methods for microbial and planktonic communities using new-generation sequencers in order to eventually establish a practical approach to managing the quality of water in dam reservoirs. In this report, we present the results from the comparison between the microbial and planktonic communities identified using new-generation sequencers and those identified using optical microscopes.

＜抄録＞　近年注目を集めているマイクロプラスチックのうち、特に繊維状マイクロプラスチックについて、下水処理場での調査に適した簡易な検出手法の確立が求められている。本稿では、従来法による測定結果と課題点を示した後、構築したナイルレッド試薬を用いた蛍光染色観察法を紹介し、下水処理場調査への適用結果について報告する。。
Microplastics have been drawing public attention in recent years. In wastewater management, there is an urgent need to establish a simple method for detecting fibrous microplastics in wastewater samples. In this report, we first present the analytical results obtained by a conventional method while addressing the issues of detecting fibrous microplastics, and then outline the fluorescent stainingobservation method using Nile Red. We also report the application results of this new method to a survey conducted at a sewage treatment plant.

＜抄録＞　老朽化が進む河川ポンプ設備は、維持管理コストの縮減が求められており、状態監視保全の導入を進めている。本報は状態監視保全の課題である、技術者不足および「非」常用設備ゆえの課題に対応するため取組んでいるAI異常検知について報告する。
As river pumping systems around Japan are increasingly aging, condition-based maintenance has been introduced for the reduction of their maintenance and management costs. However, experts for this maintenance are in short supply while also arising are issues inherent in systems used only on an emergency basis. This report explains AI abnormality detection, which we have been developing to address such challenges.

＜抄録＞　インフラの老朽化が課題となり、全国各地で定期的な点検がはじまった。定期点検に割く労力が増大し、十分に老朽化対策に予算が割けない、新しい投資、事業に予算を回せないといった事が起こっているのではないか。インフラ調査のロボットとして有力なドローン、その開発、活用事例を紹介し、人海戦で難しかった部分にデジタル技術の活用を目指している先進事例を紹介する。
In response to increasingly aging infrastructure, responsible offices around Japan have started inspections on a regular basis and are commonly having difficulty in earmarking enough budget for aging control and new investment and projects, because regular inspection costs grow rapidly. There are, however, some pioneering cases in which digital technology is being tested for practical use in areas of infrastructure inspection that is requiring a large workforce but not producing desired results. We report such cases, focusing on drones, a powerful robotic tool for this type of inspection, including their development process.

＜抄録＞　糠田排水機場におけるポンプ運転時は設備状況の確認のため、監視員は1台につき24箇所の計器等の監視・計測を行うが、ポンプの運転台数の増加に伴って、計測作業が困難となり、注視すべきポンプ設備からの音、振動等の監視に支障をきたしていた。本稿では、このような状況を解決するために2018年度に導入した運転監視システムについて、導入に至った経緯、効果及び今後の取り組みを報告するものである。
When the pumps are in operation in the NUKATA discharge pump station, operators monitor and take readings of 24 gauges per pump. As the number of pumps increases, the task has become so demanding that it has prevented operators from monitoring the sound and vibration from the pumps that they are supposed to pay close attention to. To address this problem, we introduced a pump operation monitoring system in 2018. This report details our decision on the introduction of the monitoring system, the effect of the system, and plans for more effective pump operation.

＜抄録＞　コンクリート舗装を補修した箇所について、耐久性向上に必要な補修材の性質などを検討するため、種々の補修材を用いて、荷重車を用いた実物大試験を行った。セメント系や樹脂系補修材はアスファルト系補修材と比べ変形しにくく、半数は概ね健全な状態を維持した。一部は浮きが生じ、その後ひび割れに至った。浮の要因の1つに、コンクリートと補修材の温度変化に伴う寸法変化の差が考えられた。
To study pavement repair materials regarding properties essential to improve the durability of concrete pavement after a repair, fullscale tests were conducted using different types of repair materials and heavily loaded vehicles. Cement-based and resin-based materials were less likely to deform than asphalt-based materials. A half of those types remained in virtually good condition though some lost adhesion, which later developed into cracks. One of the potential factors that may have caused loss of adhesion was the difference between concrete and repair materials in size change rate under different temperatures.

＜抄録＞　水門の端堰柱は、地震時に自由振動する構造体と、地盤との相互作用の影響を受ける抗土圧構造物から構成される構造であるため、複雑な地震時挙動を示すものと考えられる。そこで、本報では、動的遠心力模型実験と動的FEM解析により、水門端堰柱の地震時挙動に関する分析を行った結果を報告する。
Comprised of a structure that vibrates freely and a retaining structure that interacts with ground movement in time of an earthquake, the edge walls of water gates behave in a very complicated way. To understand such complex behavior, we analyzed the behavior of water-gate edge walls during an earthquake by conducting dynamic centrifuge tests and dynamic FEM analysis. The results are presented in this report.

＜抄録＞　河川堤防の長期安全性に関する調査・研究は少ない。そこで、安全性の低下が懸念されるドレーン工等の周辺に高い動水勾配が作用した場合に着目し、土粒子の移動や目詰まり等に関する要素実験及び実際の堤防における開削調査を実施した。その結果、要素実験からは土粒子が移動したことによる局所的な目詰まりは見られたものの全体的な透水性の低下は生じなかった。また、開削調査でも、明確な目詰まりは確認されなかった。
Little research has been done on the long-term safety of river embankments. Focusing on cases where a high hydraulic gradient acts on the region around drain work, whose safety is assumed to decrease over time, we conducted element tests to investigate the movement of soil particles and the process of clogging and carried out open-cut surveys of river embankments. The results confirmed that the overall permeability of the drain-work region did not decrease, although the element tests found clogging locally due to the movement of soil particles. The open-cut surveys also confirmed no distinct clogging.

＜抄録＞　砂浜が有する利用上の価値の評価手法を開発するうえで必要な砂浜訪問者の出発地と到着地、旅行手段を把握するための全国WEBアンケート調査し、あわせて砂浜の通年での利用実態を把握するための携帯電話の発信位置情報を九十九里海岸、新潟海岸で実施した。得られた結果を踏まえて、砂浜の利用上の価値を評価するうえでの留意点を述べた。
We conducted a nationwide web questionnaire survey to collect travelers’ information needed to develop a method to evaluate the value of a beach. The information collected was each traveler’s starting point, destination, and transportation they used. We also collected mobile-phone calling location information in the Kujukuri and Niigata beaches of Japan to analyze the use of beaches throughout the year. Based on the results, we discuss some considerations to keep in mind in evaluating the value of a beach for public use in this report.

＜抄録＞　本報では、アスファルト舗装の再生利用を持続的に維持する目的で、繰り返し再生に適した再生用添加剤の成分組成を室内実験により確認した。また、ホイールトラッキング疲労試験を実施し、再生アスファルト混合物のひび割れ抵抗性を検証した。その結果、芳香族分の多い再生用添加剤の有効性を確認したので報告する。
We have been studying sustainable recycling of asphalt pavement. To this end, we conducted indoor experiments to analyze the component compositions of rejuvenators known as suitable for asphalt recycling. We also conducted wheel tracking fatigue tests to examine the crack resistance of recycled asphalt mixture. The results confirmed that rejuvenators containing more aromatic components were more effective for repeated asphalt recycling.

＜抄録＞　近年、岩盤を支持層とする杭の設計・施工事例が増加してきているが、沈下等の不具合を起こす事例が散見されている。また、支持層全体が大きな傾斜や不陸を有することが少なくないため、適切な調査方法を示していく必要がある。岩盤を支持層とする杭基礎の地盤調査法に関する共同研究で得られた知見の一部を紹介する。
In recent years, more piles are designed and constructed to be embedded in the bearing layer of rocks. However, flaws, such as sinkage, have been reported in some cases. Since quite a few bearing layers have a large slope or unevenness, an appropriate method to investigate such characteristics of bearing layers should be developed and disseminated. This report provides some of the findings from joint research on ground survey methods to be employed for embedding piles in the bearing layer of rocks.

＜抄録＞　本研究では、従来の2次元図面から3次元モデルを契約図書とすることを目的に、3次元モデルに寸法や注記を付与する試行を実施した。2次元図面と3次元モデルの両方を作成する従来方法の作業時間と比較した結果、作業時間が同等程度であることを確認した。
In this study, we experimentally added dimensions and annotations to a 3 dimension model (3D model) in order to convert a conventional 2 dimension contract drawing (2D drawing) to a 3D model. We compared the work time between the new method of directly adding dimensions and annotations to a 3D model and the conventional method of making a 2D drawing and then a 3D model. The comparison confirmed that the new method has the same work time.

＜抄録＞　近年、増加が著しい老朽化したインフラへの対策を推進するために、平成31年4月1日に関東地方整備局と中部地方整備局へ設置された道路メンテナンスセンターの令和元年度における直轄国道上の道路構造物保全への係わりと地方公共団体への技術支援等の実績を交えながら、その役割と取り組みを紹介するものである。
An increasing number of aged structures have been reported throughout Japan in recent years. To accelerate the maintenance of such infrastructure, the Road Maintenance Management Office was established on April 1, 2019, in the Kanto Regional Development Bureau and the Chubu Regional Development Bureau of Japan. This report describes the role and activities of the newly established office with examples in 2019 of how the office maintained road structures that are under the management of the national government and provided technical assistance to local governments.

＜抄録＞　地方の道路橋RC床版劣化の顕在化と管理する橋梁特徴的構造（斜角・曲線･隅切りを有した構造）及び地方のインフラ維持管理を支える技術者不足に着目し、産学連携の中で地域の身の丈にあったプレキャストRC床版を提案し、地方の建設会社が設計施工とその実証実験を行ったものである。
Local municipalities have common issues regarding RC slab replacement. RC slabs used for road bridges are evidently deteriorating; each bridge under their management has its own structural characteristics such as oblique angles, curves, and corner cuttings; and skilled engineers needed for infrastructure maintenance are increasingly in short supply. This report presents an empirical case study, in which the academic and industrial sectors collaborated and proposed low-cost precast RC slabs and a local construction firm designed and carried out a replacement project.

＜抄録＞　気候変動に適応した河川整備の計画的かつ速やかな実施に資するため、河川整備の目標とする降雨外力に気候変動による将来変化を定量的に反映することを目指し、アンサンブル気候予測データを使用して、河川整備の計画規模に概ね相当する1/100確率降雨量の将来変化率を試算した。
To design and implement river improvement for climate change adaptation systematically and promptly, it is necessary to quantitatively reflect climate change-induced changes in precipitation in the design precipitation conventionally set for river improvement. To this end, we estimated the change rate of 1/100 precipitation, which is roughly equivalent to the design scale for river improvement, using ensemble climate prediction data.

＜抄録＞　洪水対策施設設計規模を上回る豪雨・洪水が頻発する中で、着実な施設整備に加え地域の浸水特性等に応じて様々な主体が参画する水害対策の推進が重要である。本稿は同対策の推進に必要な浸水想定図等の浸水ハザード情報について、利用者の観点から必要と考えられる内外水氾濫を統合した作成手法の開発について紹介する。
Heavy rains and floods that exceed the design scales of flood control structures have been increasingly frequent. To prepare for such events, it is important to take non-structural flood risk reduction measures by involving various actors, depending on area-specific flood characteristics, in addition to the constant implementation of structural measures. One example is flood hazard information, such as flood risk maps. This report explains the development of a hazard assessment method capable of estimating integrated flood risk by taking both riverine and urban floods into account, which is a type of flood hazard information essential for the public to protect themselves.

＜抄録＞　国総研気候変動適応研究本部が実施した「気候変動化の都市における戦略的災害リスク低減手法の開発」において、都市における多様な建物の水害リスクと建築・敷地レベルのリスク低減策の評価手法及び、まちづくりと連携した水害リスク低減策の取り組みに関して調査・研究を行った内容を紹介する。
The Climate Change Adaptation Research Group of the National Institute of Land and Infrastructure Management of Japan conducted research on the development of a strategic disaster risk reduction approach for climate change-affected urban areas. In this report, we present a method to assess the flood risk of various buildings in urban areas and describe risk reduction measures for individual buildings and premises. We also explain the investigations and research that we conducted in an effort for flood risk reduction coupled with urban planning.

＜抄録＞　近年、土地利用の高度化や降雨状況の変化の影響を受けて、都市の浸水被害リスクが高まっている。一方下水道事業では、従来からのハード整備に加えて、既に整備された様々な施設をストックとして活用した浸水対策を推進している。本稿では、ストックを活用した都市浸水対策として、「下水道革新的技術実証事業」で実施した浸水対策に関する2つの技術について紹介する。
In recent years, urban inundation risk has been steadily increasing due to more efficient land use and more intense rainfall. To address this issue in sewage management, inundation control measures have been in place using different types of existing sewage facilities and structures, in addition to conventional measures relying on structural development. In this report, we present two types of technology that were designed to control inundation using existing infrastructure and implemented in the demonstration projects for innovative sewage technology.

＜抄録＞　九州では、災害報道の充実を目的とする「九州災害情報（報道）研究会」において報道機関や学識者、行政機関が参画し議論・検討を行っている。令和元年度はアナウンサーなど直接の伝え手を交えた勉強会や、洪水時に気象台と整備局が合同で危機感を呼びかける記者会見を行うなどの取組を展開しており、その活動を紹介する。
In the Kyushu region of Japan, a study meeting has been organized to improve disaster coverage, and the members consisting of news media, academics, and government agencies have been discussing various issues regarding the subject. In 2019, for example, the meeting invited news broadcasters and studied effective ways to communicate disaster information to the public and supported a local meteorological station and the Kyusyu Regional Development Bureau in holding a joint press conference to appeal to the public to have a sense of crisis during a flood. This report presents such activities in detail.

＜抄録＞　平成28年8月北海道大雨激甚災害に対するハード・ソフト一体となった緊急的な治水対策の実施状況に加え、令和元年度には、「北海道地方における気候変動を踏まえた治水対策技術検討会」を開催し、十勝川流域等をモデルとして、大量の気候予測アンサンブルデータを活用して進めている詳細な水害リスク評価や適応策等の検討内容を紹介する。
In response to the devastating heavy rain disaster in August 2016 in the Hokkaido region of Japan, emergency flood control measures, consisting of structural and non-structural measures, have been implemented in the disaster-stricken region. To strengthen the region’s preparedness, a study group was also launched in 2019 to discuss additional flood control measures as part of the region’s climate change adaptation effort. For example, the study group has conducted extensive flood risk assessments for the Tokachi and other river basins using a large ensemble of climate simulations. This report presents a detailed explanation of this assessment and plans for other adaptation measures.

＜抄録＞　床版上面のコンクリートの土砂化など、劣化形態が多様化している道路橋コンクリート床版の耐久性を確保するため、防水層を含めた橋面アスファルト舗装の防水性能の確保が重要な課題である。本文では、これまでの課題を示すとともに、現時点での知見を踏まえて、床版防水に配慮した橋面舗装の打換え技術の骨子を提示した。
Asphalt surfacing with certain waterproof performance on concrete decks for road bridges is indispensable to the durability of the bridge decks suffering from the disintegration of concrete on the decks and various kinds of deterioration. This report outlines the major issues to improve the waterproof performance on the decks, and proposes the concepts of repair and renewal for effective waterproofing when replacing the asphalt layers on the decks.

＜抄録＞　海岸侵食対策の検討において、その海岸が如何なる材料を基盤として如何に形成されたかを把握することは不可欠である。そこで、海浜表面からは知り得ない、海浜内部の構成や堆積・侵食の過程を把握できる多面的解析を用いたトレンチ調査手法を開発した。本報では、静岡県の浜松篠原海岸での事例でその有効性を示す。
In planning coastal erosion control measures, it is essential to understand how the coast was formed out of what material. For this purpose, we have developed a new survey technique named the trench survey technique, which is capable of multifaceted analyses that allow the user to understand the inner composition of the coast, which is impossible to know from the outside, and the processes of deposition and erosion. In this report, we explain the usefulness of this technique, presenting the case of the Hamamatsu-Shinohara beach in Shizuoka Prefecture, Japan.

＜抄録＞　土木研究所iMaRRCでは、塩害抵抗性を高めたコンクリートの迅速評価手法として、急速塩分浸透試験と電気抵抗率試験を提案してきた。本稿では、産地等の異なる混和材や品質の異なる細骨材を用いたコンクリートを対象にこれらの試験を行い、その結果を一般的な試験方法である塩水浸せき試験の結果と比較して適用性を検証した。
The iMaRRC in the Public Works Research Institute of Japan has been proposing the rapid chloride permeability test and the electrical resistivity test as time-efficient methods to evaluate concrete with high chloride resistance. We conducted these tests for concrete samples containing supplementary cementitious materials derived from different localities or different types of fine aggregate. This report discusses the applicability of the proposed tests by comparing the results of the two tests with those of the chloride ponding test, which is a conventional test method.

＜抄録＞　本報告では、トンネルの補助工法として近年適用事例が多く報告されている長尺鋼管先受工に着目し、モデル化手法および打設範囲を変えた3次元数値解析を行い、モデル化手法や打設範囲の違いが支保構造の変形挙動および応力状態に与える影響についての把握を試みた結果について報告する。
This report focuses on forepiling method, which has recently been applied to many mountain tunnel constructions as an auxiliary method. Based on the results of 3D numerical simulations of this method with different modeling approaches and installation ranges, we discuss how the difference in modeling type and installation range can affect the deformation behavior and stress resistance of the tunnel supporting structure.

＜抄録＞　コンクリート舗装は設計期間を20年とされているなかで、平泉バイパスは供用20年になり設計期間を迎え、疲労などによる損傷が発生することも予想される。そこで、本報では、コンクリート舗装の各性能の経年変化を把握することを目的に追跡調査を実施した結果を報告する。
In Japan, the design service period is set to be 20 years for concrete pavement. As it has been two decades since it was put in service, Hiraizumi By-pass Road is assumed to have some damage due to fatigue and other aging-related conditions. In this report, we present the results of a follow-up investigation conducted to analyze long-term changes in the different properties of concrete pavement.

＜抄録＞　平成30年7月豪雨における直轄管理国道の土工区間104箇所の被災事例について被災状況を整理し、道路機能に着目した被災状況の分析結果と、抽出区間における地形・地質状況との関連性を含めた被災状況の分析結果について報告する。
The extreme rainfall in July 2018 caused significant damage to many places across Japan. Among them, we selected 104 earthwork sections of national roads under the direct management of the central government and analyzed the damage in those sections. This report presents analysis results, particularly focuses on damage categorized by road function and damage in relation to topographical and geological features.

＜抄録＞　排砂バイパストンネル等の摩耗損傷対策として施工されたライニング材が剥離する要因として、不陸による負圧の可能性が考えられる。そこで、不陸を模擬した実験水路において、最大18.8m/s程度の流速下において負圧の計測を連続的に行った。不陸の高さと流速を変化させ、負圧の値およびその発生範囲を明らかにした。
Lining material, applied to the inner walls of sediment bypass tunnels for abrasive wear control, peels off in some cases. One possible cause for this phenomenon is assumed to be negative pressure due to unevenness in the wall surface. To prove this hypothesis, we conducted experiments using a testing flume with an uneven wall surface and continuously measured negative pressure generated by high-speed flows as fast as 18.8 m/s. We repeated experiments with different heights of unevenness and flow speeds and confirmed the corresponding values of negative pressure and its occurrence range.

＜抄録＞　トンネルと排水機場の点検データの高精度化のために無線モニタリング機器が有効だが、トンネルと排水機場における無線通信の信頼性はほとんど検討されていない。本研究では、無線モニタリング機器の通信周波数とネットワークトポロジーをどのように組み合わせればトンネルと排水機場で無線通信の信頼性を確保できるか、実験により明らかにした。
Wireless monitoring devices have been acknowledged to be an efficient tool to collect accurate data from inspections of tunnels and drainage pump stations. However, little research has been done regarding the reliability of wireless communication for such cases. In this study, we found out how reliable wireless communication can be achieved by testing combinations of different frequencies of wireless monitoring devices and the network topology.

＜抄録＞　国総研では、当所の研究や活動の内容とその意義を周知するため、積極的な広報活動をしてきている。その一環として、国総研が約四半世紀にわたり実施している「ボール紙で作る橋コンテスト」について報告する。本研究の分析などより、当コンテスト参加者の意識には、社会基盤整備の世界がつながっている様子をうかがうことができた。
The National Institute for Land and Infrastructure Management has been actively promoting itself for better public relations by providing information about its goals, research, and other activities. As a part of such efforts, the institute has hosted the "Bridge Papercraft Contest" annually for about 25 years. After reviewing the past contests, we found that the event has been an excellent opportunity for participants to get well-acquainted with the world of social infrastructure through constructing paper bridges.

＜抄録＞　東京外環自動車道と京葉道路との接続部である京葉ＪＣＴは各ランプ部が全てトンネル構造であり、かつそのトンネル内でそれぞれの方向に分岐または合流する地下ＪＣＴとなっている。この地下ＪＣＴという特殊な空間での非常時における確実な避難誘導の為に設置した足元誘導灯設備他について紹介する。
The KEIYO Junction, which is the connection between the GAIKAN Expressway and the Keiyo Expressway, has tunnel structures for all ramps, and has structures that branches or merges in each direction within the tunnels. We report the implementation of the foot guidance lights and other equipment installed for reliable evacuation guidance in an emergency in these underground space.

＜抄録＞　静岡市の舗装維持管理に関し、維持管理計画策定から10年が経過し、蓄積された点検結果や国が策定した舗装点検要領の内容、舗装に関する新たな技術を踏まえ、維持管理計画を改定し効率的な維持管理を実施する。
It has been ten years since Shizuoka City formulated and executed a maintenance and management plan. The plan has been revised for the implementation of more efficient maintenance and management, based on the results from data collected over this period, the contents of the pavement inspection guidelines formulated by the national government, and new pavement construction techniques.

＜抄録＞　河川域における渉禽類の出現傾向を精査した結果、内陸淡水域を主に利用する種の減少傾向が示された。また，堤内外地を含めた環境と渉禽類の出現との関係性を解析し、種によって、堤内の水田などの存在が重要となることが示唆された。これらの結果を踏まえ、河川における鳥類の保全優先地区の考え方を示した。
We studied the occurrence tendency and habitat types for wading birds in both river and landside environments in Japan. The study revealed that the number of wader species which inhabit inland freshwater bodies has recently decreased in Japanese rivers. The study also found that wide paddy fields contributed significantly to the appearance of these waders. Based on these results, we discussed the concept of priority areas for bird conservation in river environments.

＜抄録＞　掘削後の川幅が維持できる掘削幅を設定し、再樹林化の抑制やサケの産卵環境の維持が図れるように掘削敷高を設定した。掘削した場合の河道変化、流況変化について予測計算を実施し、掘削なしの場合と比較して、サケ産卵可能面積の改善につながり、その効果は少なくとも3年後までは維持されることが確認された。
In an excavation project, we set the excavation width in the way that the river width after the excavation would be maintained and the excavation bed height in the way that it would help prevent the re-vegetation of the area and conserve the spawning environment of salmon. We simulated changes in the river channel and regime after the excavation and compared them with those without the excavation. The results found that the excavation would increase the area of the spawning space for salmon and that the effect would continue at least for three years.

＜抄録＞　昨今の降雨の激甚化を鑑みると、治水メニューの一つである河道掘削の重要性は高まっている。本報文では、掘削地盤高と土砂堆積および植物繁茂との関係に焦点をあて、掘削後の維持管理に資する河道掘削断面を計画、設計するための考え方を示す。さらに、河道内樹林化の一因であるヤナギ類を対象にその繁茂抑制技術を紹介する。
Considering increases in rainfall intensity in recent years, channel excavation as one of flood control measures has become even more important. In this report, focusing on the relationships of the excavated ground surface with sediment deposition and vegetation growth, we present a concept for planning and designing cross-sections in channel excavation contributing to river management. The report also includes a method for preventing the overgrowth of willow trees, which is one of the causes of forestation in river channels.

＜抄録＞　自然共生研究センターでは、iRICソフトウェアを活用した「河川CIM支援ツール」の開発を通じて、今まで2次元だった河川空間の設計などを3次元で取り扱う新しい川づくりを推進している。本報では、河川CIMの推進に重要な3つの機能を支えるツール群の技術開発に関する紹介を行う。
The Aqua Restoration Research Center has developed the River BIM Support Tool using iRIC software. With the tool, which allows users to create 3-dimensional river space designs instead of conventional 2-dimensional ones, the center has been promoting a new type of river design. In this report, we explain the technological development of a group of tools that support three critical functions needed to promote river BIM.

＜抄録＞　梯川で今後事業を実施する8.0～9.0kは、梯川における唯一の蛇行区間で、自然裸地、ツルヨシやススキ群落、崖地、早瀬、淵などの多様な環境が存在している。このため、工事後も自然環境が回復することを目的に、将来河道における河道特性（無次元掃流力等）が現河道と大きく変わらないよう護岸設計を行った。
A river improvement project is planned for the 8.0-9.0 k section of the Kakehashi River in Ishikawa Prefecture of Japan. This section is the only meandering section of the river with various riparian environments such as natural bare land, communities of crested reed and Japanese pampas grass, cliffs, ripples, and pools. For the natural environment to return to the area after the project, river revetment was designed to ensure that the channel characteristics such as dimensionless tractive power would remain roughly at the same level in the improved channel as in the current channel.

＜抄録＞　岩手県岩泉町を流下する安家川は、平成28年8月の台風第10号により甚大な被災を受けたことにより、およそ2.7㎞の区間において改良復旧事業を行っている。本事業では、再度災害の防止に加えて、地域の景観、自然環境を守る様々な取り組みを行っていることから、その概要を報告し、これからの災害復旧事業に資する。
The Akka River, running downstream in Iwaizumi Town of Iwate Prefecture, suffered significant damage when Typhoon No.10 hit the area in August 2016. Because of that, a river improvement and restoration project has been underway in its 2.7-km-long section. This project is designed not only to protect the area from hazards in the future but also to conserve the area’s scenery and nature. This report outlines the project to contribute to future post-disaster restoration projects.

＜抄録＞　下水道から排出される温室効果ガスについて20％削減が目標とされており、排出抑制技術が必要である。本稿では、温室効果が二酸化炭素の約298倍と言われている一酸化二窒素の排出量を調査した。その結果、標準法及び疑似AO法を採用する処理場において季節ごとのN2O排出量が大きく変動することが確認された。
A 20% reduction target has been set for greenhouse gas emissions from sewers. To achieve the goal, effective emission control technology is critical. In this research, we investigated the emissions of nitrous oxide, whose greenhouse effect is said to be about 298 times that of carbon dioxide. The results found that the N2O emissions show large seasonal fluctuations particularly at sewage treatment plants using the standard treatment method or the pseudo Anoxic Oxic method.

＜抄録＞　平成28年熊本地震で被災した鋼5径間連続非合成曲線鈑桁橋である大切畑大橋の復旧においては、断面改造によって上部構造としての耐荷性能を挽回する補修方法を選定した。本稿では、その設計の考え方や配慮事項を紹介する。また、復旧の施工プロセスで生じる力を活用して行った補修設計の妥当性の検証について報告する。
Ookirihata Ohashi Bridge, a 5-span continuous curved steel plate girder bridge, suffered significant damage during the 2016 Kumamoto Earthquake. In the restoration project, we selected a repair method to recover the load-bearing capacity of the superstructure through cross-sectional remodeling. This report presents the concept of the restoration design and key considerations taken into account. We also report a method to investigate the validity of the restoration design using the force arising in the process of the restoration project.

＜抄録＞　本報文は、フィルダム内部のひび割れ調査に有効な、電気探査を用いたひび割れ深度調査に適した注入材料について検討し、屋外地盤での電気探査試験により、適用に向けた基礎的な検討を実施したことを報告するものである。
Electric resistivity survey is expected to be an useful method to investigate cracks which could be formed in embankment dams due to large earthquakes. In this study, several filler materials for the survey to estimate crack depth were examined in laboratory experiments and outside ground survey tests were conducted for a selected material to evaluate its practical applicability.

＜抄録＞　UAVを使用した中小河川での地形測量手法を検討するため、植物の繁茂状況や河道特性の異なる5つの河川で撮影方法を変えた検証を行った。検証の結果、垂直写真に垂直から20°程度傾けて撮影した斜め写真を組み合わせることで、冬季に植生が倒伏する河川では、一定の精度で堤防、桁下高、河道地形が計測できた。
To develop an efficient method to capture the topographic and other features of small and medium rivers using UAV photogrammetry, we tested different photographing approaches for five rivers, which varied in levels of vegetation and characteristics of river channels. The results revealed that, when photos were taken of rivers with little vegetation in winter, levees, bridge clearances, and river shapes can be captured with reasonable accuracy by combining vertical photographs with ones taken at some 20° angle from the vertical.

＜抄録＞　表層の地盤条件をパラメータとした動的遠心模型実験により、レベル2地震動に対する橋台と地盤の地震時挙動及び橋台に作用する力の計測と分析を行った。その結果、地盤条件の違いで異なる傾向となることを示し、現行の道示による設計は安全側となっているものの、地盤条件の違いを考慮することで合理的な設計となる可能性を確認した。
In this study, we investigated and analyzed the seismic behavior of ground and abutments and the force that acts on abutments. Dynamic centrifuge model tests were conducted by varying the surface-layer ground condition and simulating a level-2 earthquake vibration. The results showed that their behavior and the force vary in ground condition, we confirmed that the bridge design can be improved by considering the ground condition, although the current design, practiced in Japan according to the Specifications for Highway Bridges, is on the safe side.

＜抄録＞　硬質瀝青管は、破損、木根侵入、閉塞といった問題が発生しており、地方公共団体は維持管理に苦慮している。本稿では、長期間の洗剤浸漬によるコールタール含有率の変化、高圧洗浄による管への影響、水ぶくれの程度の観点から評価した強度試験結果を踏まえ、硬質瀝青管の維持管理における留意点を報告する。
Local governments are having difficulty maintaining pitch fiber pipes because they are severely damaged from fracture, root penetration, clogging and other problems. To address these problems, we evaluated the strength of pitch fiber pipes by examining changes in coal tar content due to long-term soaking in detergent, the impact of high-pressure cleaning on pipes, and blister. Based on the results, we present key points for the maintenance of pitch fiber pipes.

＜抄録＞　本報文では、MMSで取得した画像及び点群データから道路案内標識の位置及び板面に記載された案内地名のテキストデータを抽出するプログラムの試作及び評価結果を報告する。標識の位置を約9割の精度で抽出できるが、案内地名のテキストデータ抽出については、精度向上のための改善余地が大きいという知見を得た。
In this study, we developed and evaluated a prototype program to locate road guide signs and extract destination names as text data from images and point cloud data captured using the Mobile Mapping System (MMS). The results showed that the program can locate road guide signs with approximately 90% accuracy. However, they also showed that more improvement is needed to extract destination names from the signs with reasonable accuracy.

＜抄録＞　本稿では、鋼繊維補強コンクリートを用いたトンネル覆工のひび割れ抑制効果を確認することを目的とした実トンネルの試験施工の結果を報告する。10年以上にわたる長期計測の結果、覆工に鋼繊維を混入することにより、ひび割れ発生後の進行を抑制する傾向が確認できた一方で、ひび割れの発生自体を防止する効果は確認されなかった。
In this study, we investigated the crack control effect of tunnel lining using steel fiber reinforced concrete by applying it to an actual tunnel experimentally. The over-a-decade-long experiment confirmed that steel fiber reinforced concrete can prevent the progress of cracks. However, it did not confirm that the concrete can prevent the onset of cracks.

＜抄録＞　国土交通省近畿地方整備局琵琶湖河川事務所では、天ヶ瀬ダム再開発事業を行っている。淀川水系にある天ヶ瀬ダムの左岸側にトンネル式放流設備を整備する事業である。事業工期が、残すところ1年半となり、大詰めを迎えた天ヶ瀬ダム再開発事業について、設計と施工の両面から紹介する。
The Lake Biwa River Office of the Kinki Regional Development Bureau of the Ministry of Land, Infrastructure, Transport and Tourism, Japan, is operating the redevelopment project of the Amagase Dam, which is located in the Yodo River system. The project, aiming to construct a tunnel-type discharge facility on the left side of the dam, has entered its final stage with one and a half years left to complete. This report provides an overview of the project in terms of design and construction.

＜抄録＞　那賀川流域は国内有数の多雨地帯であることから数年に1回、甚大な洪水が発生する。このため洪水調節機能の増強を主体として長安口ダム改造事業に平成19年から着手した。当事業では国内でも前例のない規模のダム堤体切削やゲート2門の増設などを実施した。本稿では長安口ダム改造事業について報告するものである。
The Nakagawa River basin is located in one of the rainiest areas in Japan, and thus large-scale flooding occurs once in several years. To reduce flood damage in the basin, the Nagayasuguchi Dam Reform Project started in 2007 primarily to strengthen its flood control capacity. In this project, two additional gates were built, and dam-body cutting, whose scale was unprecedented in the country, was executed. This report presents the details of the reform project.

＜抄録＞　新設橋に関する技術基準である道路橋示方書では平成14年以降、信頼性設計に基づく性能規定化が進められてきた。道路橋の効率的な維持管理のためには既設橋梁の補修補強設計に関する基準類の整備も必要である。このことから、本稿では昨今の国総研にて実施している研究概要を紹介する。
In the Specifications for Highway Bridges, which provides technical guidelines for the construction of new bridges in Japan, the standardization of specifications has been promoted based on the concept of reliability-based design since 2002. For the efficient management of road bridges, however, it is also indispensable to develop guidelines for designing the repair and reinforcement of existing bridges. This report provides an outline of research on this effort made by the National Institute for Land and Infrastructure Management.

＜抄録＞　災害に強い信頼性の高い道路網構築のため、大規模地震等による道路機能への影響を最小限に留められるような設計、施工等を行っていくことが求められる。本検討では地震による液状化の影響を受けるカルバートの挙動について、再現解析及び模型実験等により発生要因等を明確にすることを試みたので、その検討概要について紹介する。
In order to build road networks that are reliable and resilient to disasters, it is essential to design and construct roads and related structures in the way the impact of a large-scale earthquake on them can be minimized. To this end, we conducted reproduction analyses and model experiments to study the behavior of culverts that will be subject to liquefaction in the event of an earthquake to identify possible causes. In this report, we present an outline of our research and findings.

＜抄録＞　道路土工構造物の点検に際しての留意事項や点検結果の分析により得られた道路土工構造物の変状の傾向を紹介するとともに、近年の災害からの知見も含め被災を軽減させるための技術基準の今後の方向性について提案する。
In this report, we introduce a tendency of changes in road earthwork structures, which was revealed by analyzing key inspection points and inspection results. We also provide of the direction of technical standards and the efforts for disaster damage reduction by the National Institute for Land and Infrastructure Management of Japan, including lessons and knowledge from recent disasters. We conducted an analysis of damage situations by examining 104 earthwork sections of national roads under the central government’s management for damage caused by the July 2018 heavy rain from different viewpoints, including road functions and the relationship between the topographical and geological conditions. We report the analysis results of the disaster damage analysis as well.

＜抄録＞　本稿では、道路被災状況調査に利用可能なリモートセンシング技術の適用条件を整理するととともに、それらの技術を用いた被災情報の取得方法に関するケーススタディを行ったので報告する。
The conditions for applying remote sensing technologies for road damage surveys are summarized. In addition, we report the results of a case study conducted on how to obtain disaster information using such technologies.

＜抄録＞　道路橋の維持管理は暗黙知に支えられている部分も大きく、技術者の育成において目標とする技術力の全体像や構成要素が整理されているケースは稀である。本稿は、戦略的な人材育成の実現に向け、道路橋を維持管理するための判断行為や検討内容の1つ1つを「ブルーム・タキソノミー」の枠組で分類し、技術力の解明を試みる。
In the maintenance of road bridges, there are areas where tacit knowledge plays a vital role. Because of that, objectives of human resource development such as perspective and components of technological capabilities are rarely provided in human resource development of each organizations. This paper attempts to elucidate technological capabilities by classifying technical decision making, surveys and so on one by one conduced in some case of problem handling processes of road bridges based on Bloom’s taxonomy.

＜抄録＞　櫃石島高架橋(トラス部)の耐震補強は、道路鉄道併用橋を含む鉄道橋で、国内で初めて全体系の免震化を実現した。本稿は、トラス桁の既設鋼製支承を免震ゴム支承へ取替えて全体系免震化工法を採用した経緯、ノックオフ機構を有する支承構造への変更、道路及び鉄道の供用を確保しながら行ったトラス桁支承取替について報告する。
In the seismic retrofit project of the truss portion of the Hitsuishijima viaduct, existing steel bearings of the truss girder were replaced with the isolation rubber bearings. This paper reports the details of the adoption of the seismic isolation method for the total system of the bridge, which is unprecedented method for railway bridges including highway-railway combined bridges in Japan, and the introduction of the isolation bearings with a knock-off mechanism, and replacement of the bearings of the truss girder while keeping both the expressway and the railway open for traffic.

＜抄録＞　平成29年に改正された道路橋示方書では部材の塑性域まで考慮した限界状態設計法が取り入れられているものの、鋼桁においては非弾性挙動の開始点が用いられたままとなっている。このため、様々な組み合わせ断面力に対する鋼桁の限界状態の設定や設計式を提案するための基礎データとして、コンクリート床板を有する鋼桁の曲げ耐荷力実験を行った。
The Specifications for Highway Bridges, revised in 2017 to include the limit state design method with plastic ranges of members, still applies the starting point of inelastic behavior to steel girders. We conducted bending experiments on steel girders with concrete slabs to propose limit state settings and design equations for steel girders to cope with various combinations of sectional forces.

＜抄録＞　平成28年8月に発生した北海道豪雨災害を踏まえ、十勝川流域等をモデルとして進めている、気候予測アンサンブルデータを活用した水害リスク評価、それをもとにしたハード・ソフト等による具体的な適応策等の検討内容を紹介する。
In this research, we are conducting flood risk assessment using climate forecasting ensemble data for the Tokachi River basin in northern Japan as a model basin, which is the area hit by the Hokkaido heavy rain disaster in August 2016. In this report, we present the assessment results with possible adaptation measures, both structural and non-structural, proposed based on the assessment results.

＜抄録＞　国総研では、自治体における下水道施設の耐震対策計画の策定等の補完データとしての活用を目的に下水道管路地震被害データベースの運用及び公開を行っている。ここでは、平成30年に発生した北海道胆振東部地震等における下水道管路施設の被害情報整理とデータベースへの追加を行い、その結果を踏まえて被害傾向分析を行ったものである。
The National Institute of Land and Infrastructure Management of Japan operates and offers a database of seismic sewerage damage as additional data for local governments to use in developing earthquake-resistant measures for sewer pipes and facilities. Sewerage damage caused by the 2018 Hokkaido Eastern Iburi Earthquake has also been analyzed and added to the database. This report presents the results of the damage trend analysis conducted regarding this earthquake using the database.

＜抄録＞　想定最大規模洪水時の想定浸水範囲・浸水深等を表示した洪水浸水想定区域図の作成対象外である、全国の膨大な延長の小規模河川のハザード情報空白域を早急に解消することを目的とした、航空レーザ測量（LP）データを活用した氾濫推定図作成手法の研究開発経緯と同手法が反映された手引きの概要を紹介する。
Areas surrounding small rivers are often without flood hazard information since small rivers are out of the scope of mandatory flood hazard mapping, which illustrates the possible flooded areas and depths. This issue should be addressed as soon as possible, considering that small rivers account for an enormous part of Japan's total river length. In this report, we explain the development process of a flood hazard mapping method using data collected by airborne laser survey (LP) and outline the manual that we have also devised for LP-based flood hazard mapping.

＜抄録＞　うちあげ高の現地観測手法が確立していないという背景を踏まえ、本検討では、危機管理型水位計の一つである超音波式水位計に着目し、水位計の設定を変更した上で、うちあげ高の観測可否について検証を行った。その結果、観測ノイズを除去する必要性が明らかになったが、ノイズ除去を行うことで一定の精度での観測が可能であることが示唆された。
Few observation methods have been established for the measurement of wave runup height. To address this issue, we selected ultrasonic-type water-level gages, a type classified as crisis-management water-level gages in Japan, and investigated their applicability to wave runup height observation, after changing their settings. The results confirmed that observation noise needs removing but that, with the noise removed, ultrasonic gages can be applied to wave runup height observation with reasonable accuracy.

＜抄録＞　調査・設計段階から施工者が参画する技術提案・交渉方式を活用し、発注者、設計者、施工者それぞれが持つ情報、知識、経験の融合による、国土交通省直轄工事における建設生産システム改善への取組について紹介する。
In this report, we explain our effort to improve the construction production system used for construction projects under the direct control of the Ministry of Land, Infrastructure, Transport and Tourism of Japan. In this effort, we have introduced the early contractor involvement method to integrate information, knowledge and experience of contractees, designers and contractors.

＜抄録＞　本研究は、既成市街地で多様な利用の創出と良好な景観形成が両立した道路空間再構築の国内事例を調査し、事業実現に至るまでの過程で生じた課題とその解決策を分析した。その結果は、一連の「事業段階」と、事業の目的や課題の類似性で3つに分類した「検討項目」の2軸を用いて事業実施のフロー図として整理した。
Road reconstruction projects have been conducted for many existing streets in Japan to ensure the coexistence of various activities and good landscapes. Among them, this project selected successful cases and analyzed issues that emerged in the construction process and their solutions applied to them. In this result, those were sorted out by the project phase and also by discussion point consisting of three criteria set based on the purposes of projects and similarity of issues. This paper concluded creating a project flow chart reflecting the results of the analysis

＜抄録＞　本稿では、維持管理にて活用する既存構造物の3次元モデルを省力化・低コストにて作成するため、工事完成時に納品される2次元CADデータを用いた3次元モデル自動構築の基礎技術を開発し、実際の橋梁下部構造において外形形状を正確に3次元モデル化できることを確認した。なお、本研究は、委託研究「2次元CADデータを用いたAIによる3次元モデル構築技術に関する研究」の一環として実施されたものである。
In this report, the basic technologies of the automated transformation from 2D CAD drawings, delivered at the completion of construction work, to a 3D structure model has been developed to realize a 3D representation of an existing structure for use in the maintenance and management phases. A case study of a typical bridge has been adopted and the result performed in a labor-saving and low-cost manner, and it has been confirmed that it is possible to accurately create a 3D model of the external shape of the actual bridge substructure. This study was conducted as a part of the commissioned research "Research on construction technologies of a 3D model from 2D CAD drawings by artificial intelligence technologies".

＜抄録＞　地すべり調査における孔内傾斜計観測では、地すべりの変位速度が大きい場合や維持管理を目的とした長期に渡る観測の場合など、観測用のガイド管が計器の挿入限界を超えて変形し、その後の計測ができなくなる。そこで、大きく変形したガイド管でも観測できる孔内傾斜計を開発した。
Inclinometers are commonly used for landslide investigation. However, when the velocity of landslide is large or when we observe landslide constructed countermeasure works for long-term, guide pipes sometimes become too deformed to insert an inclinometer, and we discontinue the observation. To solve this problem, we have developed inclinometers that can be used even for largely deformed guide pipes.

＜抄録＞　信濃川河川事務所はi-Constructionモデル事務所として、BIM/CIMの全面活用を前提とした事業プロセスの改善に取り組み、建設生産・管理システムの効率化をはじめとする更なる普及・拡大に取り組んでいる。本稿では、大河津分水路改修事業におけるBIM/CIMの取り組み事例を紹介する。
The Shinanogawa River Office, a model office designated to promote i-Construction, has been making efforts to improve the project implementation process for the full-scale introduction of BIM/CIM, aiming to facilitate the wider use and application of the practice in many more areas, such as the establishment of a more efficient system in construction production and management. This report presents a BIM/CIM-based restoration project conducted for the Ohkouzu Diversion Channel.

＜抄録＞　平成28年熊本地震により熊本県南阿蘇村立野において大規模な斜面崩壊が発生。この被災に対し、国土交通省は無人化施工等を駆使しながら安定化対策に取り組み、令和2年8月の「復旧技術検討会」において、対策工の妥当性及び効果を確認いただき全ての対策が完了した。本稿では、斜面の恒久的な安定化対策の完成にいたるまでの計画及び施工について報告する。
During the Kumamoto Earthquake in 2016, a large-scale slope failure occurred in Tateno of Aso Village, Kumamoto Prefecture, Japan. To stabilize the failed slope, the Ministry of Land, Infrastructure, Transport and Tourism of Japan introduced unmanned construction and other approaches. In August 2020, the Recovery Technology Conference was held and verified that the applied approaches were valid and effective, which completed the project. In this report, we explain the plan and construction carried out for the permanent stabilization of the failed slope.

＜抄録＞　本研究では、既設道路橋におけるフーチング部材の耐震性能を精度よく評価できるように、杭列配置の影響を考慮したフーチングの耐震性能の評価手法を開発している。本報では、異なる杭列配置を有するフーチングモデルの数値解析に基づき、杭列配置がフーチングの地震時損傷形態に与える影響を中心とした検討結果を報告する。
In this research project, we have been developing a method to evaluate the seismic resistance of bridge hooting while considering bridge pile arrangements in order to achieve a more accurate evaluation of the seismic resistance of the hooting members of existing road bridges. We have conducted numerical analyses using hooting models with different pile arrangements. In this report, we present the analysis results, primarily focusing on the effect of pile arrangements on the seismic damage patterns of bridge hooting.

＜抄録＞　近年の大地震において、沢部を横断する道路盛土が大規模崩壊し、震後の道路交通機能の確保に支障となる事例が報告されており、このような現象に対する簡便な解析手法の提案が求められている。本稿では、自重解析による二次元変形解析により谷埋め高盛土の遠心力載荷実験を模擬した解析を行い、解析手法の適用性等について報告する。
In recent years, there have been reports of large-scale collapses of road embankments across valleys in major earthquakes, which resulted in hindrance to ensuring road traffic functions after earthquakes. To address this issue, we have proposed a simple analysis method to analyze such phenomena. In this paper, we report the applicability of the analysis method to the centrifugal loading test of a valley-filled embankment using 2D deformation analysis coupled with dead weight analysis.

＜抄録＞　谷埋め盛土の耐震性維持のために、地下水分布の把握が必要である。電気探査と観測井を組合わせて、集水地形の分布を特定する調査方法を提示する。また、数本の1次元測線記録から解析可能な、省力型の3次元探査の現場適用を行い、谷筋や宙水を特定可能な有効な手法であることを示す。
Detecting groundwater distribution is required to keep the seismic resistance of embankments across valleys. To this end, we propose a survey method for detecting the distribution of ground forms along groundwater flows. In this report, we also show the results of applying a labor-saving 3D survey method to an actual field, which confirm that the method is useful for analyzing a 3D resistivity distribution from records measured along several 1D survey lines and capable of detecting the lines of buried valleys and the locations of perched water.

＜抄録＞　河川堤防の耐震対策では地震後の堤防天端高による評価がなされているが、亀裂やゆるみ等の変状が地震後の堤防の浸透安全性に及ぼす影響については未解明な点が多い。そこで、本稿では、地震による亀裂及びゆるみの発生状況と、それらによる堤防の浸透特性の変化を調べるために行った遠心力載荷模型実験の結果について報告する。
The levee crown height after an earthquake has been used to evaluate the levee's seismic resistance. However, little research has been done to understand the effect of deformations such as cracks and loosening on the post-earthquake levee safety against seepage. We conducted centrifugal loading model tests to find out how earthquake-induced cracks and loosening may affect the levee's seepage behavior. This report presents the test results.

＜抄録＞　物流や観光など交通ネットワークの重要な役割を担っている国道325号阿蘇大橋が、平成28年4月に発生した熊本地震により落橋。本報では、阿蘇大橋の架け替えについて、将来の大規模地震に対し影響をできる限り少なくなるための橋梁計画と、道路機能の早期復旧の観点から採用した施工技術を報告する。
The Aso Ohashi bridge in Kumamoto, Japan, collapsed during the Kumamoto Earthquake in April 2016, though having been an essential part of National Route 325 and playing a vital role in the area’s transportation network for distribution, tourism, and other purposes. In rebuilding the bridge, the design was thought out to minimize seismic damage to the bridge as much as possible in future events, and construction technologies were selected to restore road traffic functions as soon as possible. This report explains the details of the design and technologies employed in the rebuilding project.

＜抄録＞　平成30年北海道胆振東部地震により、札幌市清田区里塚地区では、谷埋め盛土の造成宅地において2.5mを超える地盤沈下や大量の土砂流出など、甚大且つ珍しい様相の被害が発生した。発災から2年余りを経過した現在、対策工事は概ね完了し、住宅再建が最盛期を迎えている。本稿は対策の概要ともに復旧に向けた取組みについて紹介する。
In the 2018 Eastern Hokkaido Iburi Earthquake, Satozuka of the Kiyota ward in Sapporo, Hokkaido, the northern island of Japan, was one of the hard-hit areas. Satozuka, a large-scale embankment site that used to be a valley, experienced massive damage of rare types; part of the area sank over 2.5m deep, and sediment ran off in a large amount. Two years after the devastation, constructions to prevent disaster damage are mostly completed, and many houses are being built at present. This report outlines the constructions that have been implemented, as well as other recovery efforts.

＜抄録＞　ETC2.0 特定プローブデータの配信に用いる簡易型路側機は、無線部と制御部間の情報のやりとりに無線通信を用いるため、設置場所の条件に、通信回線の性能や周辺の電波環境が影響する。本稿では、複数の通信回線を用いた試行や疑似的に再現した電波環境を用いたシミュレーションにより、簡易型路側機の設置場所の条件を調査した結果を報告する。
Simple roadside units have been used to deliver ETC 2.0-based vehicle probe data. Since the units use radio communication to send information between the roadside units and the control units, communication lines and the radio environment are important factors in deciding the locations to install the roadside units. To find out the conditions for appropriate locations for installing roadside units, we tested several different communication lines and conducted simulations using a radio environment reproduced similarly to a real environment. The results are presented in this report.

＜抄録＞　国総研において、車両が収集した路上障害等の情報を道路管理者が収集し、後続車に情報提供するシステムの開発に取り組んでいる。本稿では、緊急通報サービスを活用した事故車等の位置特定手法について、実道での実証実験を通して、道路利用者からの電話による通報やCCTVカメラ等の従来の手法との比較により時間短縮効果を分析した結果を報告する。
The National Institute for Land and Infrastructure Management of Japan has been working on an information delivery system. This system is designed to enable road managers to garner road hazard information collected by the preceding vehicles and deliver them to the following vehicles. As part of the research, we conducted on-road tests of an approach developed to locate road hazards such as accident vehicles based on emergency call information. This report analyzes the test results in terms of time reduction effect by comparing the new approach with conventional approaches that use reports from road users through phone calls and information from CCTV camera monitoring.

＜抄録＞　本研究は、地震時挙動が複雑な土木構造物の挙動を解明することを目的とし、無線通信を用いて観測記録を回収することができる強震モニタリングシステムを構築したものである。無線通信で回収された観測記録は、解析にも十分使用できることが確認され、構造物の地震応答観測に適用できる精度であった。
The purpose of this study is to elucidate the behavior of civil engineering structures whose behavior during earthquakes is complicated. The study also aims to construct an earthquake response monitoring system that can collect observation records using wireless communication. It has confirmed that the observation records collected by wireless communication can be sufficiently used for analysis, and that the system is capable of observing the seismic response of structures with reasonable accuracy.