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In order to verify the seismic reinforcement e_ect to the RC building quantitatively, Microtremor measurement was carried out for the main building before and after the reinforcement and compared the dynamic characteristics derived from microtremors. As a result, natural frequencies estimated by the microtremor records before the seismic reinforcement are approximately 25~30% bigger than those estimated by these records after the seismic reinforcement. The results show that the reinforcement method signi_cantly increases the sti_ness of a RC building. Furthermore, this paper presents the Structural Health Monitoring （SHM） system using Internet of Things （IoT） to improve for the earthquake disaster reduction and maintainability of buildings.

In order to verify the seismic reinforcement e_ect to the RC building quantitatively, Microtremor measurement was carried out for the main building before and after the reinforcement and compared the dynamic characteristics derived from microtremors. As a result, natural frequencies estimated by the microtremor records before the seismic reinforcement are approximately 25~30% bigger than those estimated by these records after the seismic reinforcement. The results show that the reinforcement method signi_cantly increases the sti_ness of a RC building. Furthermore, this paper presents the Structural Health Monitoring （SHM） system using Internet of Things （IoT） to improve for the earthquake disaster reduction and maintainability of buildings.

In general, lap splice of the shear reinforcement of footing beams in RC structure and SRC structures makes the edge with the hook. However, the method has the problem that is to interfere in beam main reinforcements and steel flanges when constructing it. Then, the industrial method of making to the prefab which makes welded wire fabric (welded wire fabric with welded cross bar) is used. The method which uses welded wire fabric with welded cross bar is mesh reinforcement with welded cross bars (two line) on the side in the footing beam, and makes to shear reinforcement of close type as a whole. The experiment data is old and there are a lot of parts of the uncertainty now though this method is used for footing beams. In this paper, it is experimentally based of difference of the shear reinforcement shape of footing beams. The difference of the shear reinforcement shape was hardly seen at the ultimate strength.

木造住宅で一般に用いられる竹小舞下地土塗り壁のせん断繰返し載荷実験を行い, 耐力と変形性能および壁倍率などの耐震性能評価を行った。最大耐力時の変形は, 1/60-1/10radと大きい。壁倍率は, 壁土の付いた試験体では全て1.0以上であり, 現行の規定である0.5を上回っている。ホールダウン金物などにより, 接合部の破壊を防げば, 耐力壁としての機能を十分果たすと言える。壁土による耐力増加は, 筋かいの有無によらずほぼ一定であり, 筋かいによる耐力増加も, 壁土の有無に関わらずほぼ等しい。, Mud-plastered walls usually used in wood houses made by carpenters and plasterers in Kyoto were tested by repeated shear force loading in order to evaluate their seismic resistance capacities such as the relation between bearing capacity and deformability and the coefficient of effective wall length. The deformation angles at maximum load are greater than 1/60rad. The average coefficients of effective wall-length are greater than 0.5 which is the standard value determined in the Enforcement Ordinance of The Building Standard Law in Japan. It seems that if the joints of the framework are fixed by some metals such as holddown metals to avoid the separation of the framework, mud-plastered walls can function as the bearing wall. The average increases in bearing force by wall-mud are nearly same in both cases of with and without a brace, and so those by the brace are in both cases of with and without wall-mud.

制度:新 ; 報告番号:乙2175号 ; 学位の種類:博士(工学) ; 授与年月日:2008/7/31 ; 早大学位記番号:新4865

地方自治体の防災担当者が地震被害を予測するための技術力を向上させることは地震防災促進に直接の効果がある。技術力向上の方策として本研究は種々の耐震設計の共通化と構造物地震応答の可視化を検討した。情報科学の手法を使ってフローチャートを再構成し、共通の枠組みの中で土木・建築構造物の代表的な耐震設計を理解できるようにした。応答の可視化を行うため、さまざまな解析手法を統合して実行するコンピュータシステムを検討した。解析手法とシステムの通訳プログラムを作成することで統合を実現し、さらに、通訳プログラムを自動作成する人工知能の検討も行った。, It will be an important task for local government officers to improve their engineering ability of foreseeing possible earthquake damages. To this end, this paper studies the standardization of seismic resistance design and the unified visualization of structure responses in whole city. Taking advantage of informatics, we reconstruct flowchart of various design codes such that the seismic resistance design can be presented in a common framework. The usage of integrated simulation system is studied for the visualization. The integration is achieved by an artificial intelligence that automatically makes an interpreter program which links the system to various simulation programs of structures.

In order to develope cost-effective practical methods that can protect and mitigate hazards caused by overflow-induced and earthquake-induced slope failures of soil irrigation structures, a new type of reinforcement technology combined with geosynthetic reinforced soil and a soil bag system was proposed. A new type of reinforcement technology combined with geosynthetic reinforced soil and a soil bag system was proposed to develop cost-effective practical methods that can protect and mitigate hazards caused by overflow-induced and earthquake-induced slope failures of soil irrigation structures. First, a series of laboratory tests with a pile of soil bags and tensile-reinforced soil and simulations were conducted to understand the stress-strain characteristics of geosynthetic-reinforced soil. As a result, it was found that the tensile-reinforcement mechanism in developing strength was associated with deformation of backfill materials, and strongly influenced by the deformation modes and particle sizes of backfill materials. Moreover, the sliding resistance of a pile of soil bags against lateral loading can be significantly improved by stacking soil bags inclined with the inner end placed lower than the front end, similar to a masonry wall. Second, shaking table tests and hydraulic overflow-induced collapse tests were conducted in a full-scale model to validate the effectiveness of the newly designed reinforcement technology. Shaking table test results showed that slippage among bag-to-bag interfaces easily occurred in a horizontal stacked soil bag slope. On the other hand, the soil bag slope stacked inclined were stable against lateral seismic loads. Furthermore, slope facing with soil bags that have a geosynthetic reinforcement tail significantly increased substantial seismic stability. As far as erosion resistance against overflow, a slope face reinforced by soil bags with a geosynthetic sheet embedded as a tail in the embankment was very stable against temporary flooding at high overflow levels required in the field. Finally, in the field tests, it was confirmed that the construction procedures were not only simple, but also didn't need heavy machineries and costly materials (i.e., concrete and steel). This rehabilitation technology also could be successfully applied to the small earth dam damaged by the 2008 Noto Peninsula earthquake. In the pratical design, the Multiwedge method was applied for stability design of reinforced slopes. Simulation results showed that this method could be expressed the effect of the stack inclined method, and connections between soil bags and tails. It's concluded that, the reinforcement technology proposed in this study is a simple and cost-effective technology to prevent the collapse of the downstream slope by natural disasters. This method can be applied to small earth dams as well as canals, road embankments, railways, river dikes, etc.

In the 2016 Kumamoto earthquake, 10％ of Kumamoto Castle collapsed and 30％ was uplifted by the M6.5 foreshock and the Mj7.3 mainshock. However, the seismic resistance performance of the stone walls has not been confirmed with regard to the effects of seismic motion on the entire ground of the castle stone walls. Therefore, in this paper, we estimated the three-dimensional space of the ground at 35 locations surveyed before the earthquake throughout Kumamoto Castle. Therefore, we obtained the response acceleration and response speed of the stone wall by dynamic FEM analysis for 35 points throughout Kumamoto Castle, and used the results to analyze the damage factors and damage history of the stone wall due to the Kumamoto earthquake. As a result, it was clarified that the main causes of damage to stone wall structures were the collapse of stone foundations, the protruding type of semi-stone foundations, and the embankment type of non-stone foundations.

Saikai Bridge is a deck-type fixed arch bridge that was constructed in 1955. At the time it was one of a few long-span bridges in Japan, but as this was shortly after the war, the only tests carried out were operating tests during construction. Therefore in this study, ambient vibrations were measured，and the measured values of natural vibrations and the analysis values of natural vibrations obtained from natural frequency analysis were compared to validate the model and estimate the damping constant. Also, non-linear seismic response analysis was carried out to evaluate the seismic resistance, and the seismic resistance results were compared with those of the newly-constructed New Saikai Bridge(Shin Saikai-bashi).

燃料製造機器試験室(モックアップ室)は、核燃料製造設備の開発のためのウラン取扱い施設として昭和47年(1972年)に建設されたが、耐震性に脆弱であり、経年劣化が進んでいた。また、本施設では当初の目的を達成し、新規の開発計画が無い。これより、内装設備の解体撤去を平成31年(2019年)3月より開始し、汚染検査を行い、令和4年(2022年)3月29日に管理区域の解除をした。本作業における人工数は、総6,549人工(保安立会者を含まない)であり、解体撤去作業により発生した一般廃棄物量は31,300kg、放射性廃棄物量は可燃性廃棄物3,734kg(ドラム缶103本)、難燃性廃棄物4,393kg(ドラム缶61本)、不燃性廃棄物37,790kg(ドラム缶124本、コンテナ19基)であった。本報告書では、燃料製造機器試験室の内装設備の解体撤去、発生した廃棄物及び管理区域解除の手順について報告する。, Uranium handling facility for development of nuclear fuel manufacturing equipment (Mockup room) was constructed in 1972. The Mockup room has a weak seismic resistance and is deteriorating with age. Also, the original purpose with this facility have been achieved and there are no new development plans using this facility. Therefore, interior equipment installed in this facility had been dismantled and removed since March 2019. After that, the Mockup room was inspected for contamination, and then controlled area in the Mockup room was cancelled on March 29th 2022. A total of 6,549 workers (not including security witnesses) were required for this work. The amount of non-radioactive waste generated by this work was 31,300 kg. The amount of radioactive waste generated by this work was 3,734 kg of combustible waste (103 drums), 4,393 kg of flame resistance waste (61 drums), 37,790 kg of non-combustible waste (124 drums, 19 containers). This report describes about the dismantling and removing the interior equipment in the Mockup room, the amount of waste generated by this work, and procedure for cancellation the controlled area in the facility.

日本全国に広がる道路盛土の多くは，抜本的に，維持管理を要することはよく知られている．日本国内には耐震性の低い道路盛土が多数存在し，盛土材料の質が低く，不十分な締固めにより施工されていることが大きな理由の1つとなっている．これらの問題を解決するため，道路管理者にとっての緊急課題として，効率的かつ経済的な耐震補強工法の開発が必要であると考えた．そこで，本研究において，現地の盛土材を再利用することを目的に，大型土のうを用いた道路盛土の耐震補強方法を提案した．本研究資料では，既設盛土の法先部に複数設置された土のう構造体の補強効果を検証するため，Ｅ－ディフェンスにおいて実大道路盛土の震動台実験を実施し，その結果を中心に報告している．一連の実験結果から，定性的ではあるが，土のう構造体の補強効果による盛土の耐震性向上の可能性が確認された．It is well known that many of the existing road embankments spreading across Japan require drastic maintenance, because their earthquake resistance is considerably questionable due to the poor quality of the embankment materials used and insufficient compaction. In order to solve these problems, it is important to develop efficient and high cost-performance methods as an urgent task for engineers in charge of road management. Therefore, the authors proposed a seismic reinforcement method for road embankments by using flexible container bag that can reuse local embankment materials. In this study, a series of shake table tests on a full-scale road embankment was conducted at E-Defense in order to verify the reinforcement effects of the flexible container bag structures installed at the toe of the embankment. Based on the results obtained from the shake table tests, it was qualitatively confirmed that the flexible container bag structures can improve seismic resistance of the whole embankment.

震災BCPの策定支援などを目的に，建物基本情報から構造耐力を推定し，1自由度系にモデル化した建物の限界耐力計算によって建築構造・非構造部材・建築設備の被害予測を行う簡易動的耐震評価方法を提案して，その被害予測精度を検証した．近年，2011年の東日本大震災に関する各種報告書の発刊や建物の地震観測記録の公開によって，施設情報，地震観測記録，被害情報などを複合して利用できる環境が整ってきたことから，28棟の建物を対象として簡易動的耐震評価方法による被害予測精度の検証を行った．この結果，提案した簡易動的耐震評価方法は応答をやや大きめに評価する場合があるものの，被害判定ではほぼ妥当な結果が得られており，複数の既往建物の耐震性調査や地震対策の計画段階などにおけるスクリーニング評価としては有効な方法となることが確認できた., In order to support earthquake disaster BCP, the authors proposed a simple dynamic earthquake resistance evaluation method using basic information of the building, which consists of a method of estimating the load capacity coefficient and a method of predicting the damage to the building structure from the capacity spectrum method for the one-degree-of-freedom building model. However, problems such as verification of the damage prediction accuracy of a simple dynamic seismic evaluation method remained unsolved. In recent years, environments for verification analysis that include, for example, facility information, earthquake observation records, and damage information have been prepared by publishing various building damage reports and earthquake observation records for buildings affected by the 2011 Great East Japan Earthquake. For this reason, the accuracy of damage prediction by a simple dynamic earthquake resistance evaluation method was verified using public information on 28 buildings. Although the simple dynamic earthquake resistance evaluation method sometimes gives a slightly higher response value, the resultant damage assessment was for the most part reasonable. It was therefore confirmed that this method is effective as a screening evaluation method in seismic resistance surveys of multiple existing buildings and at the planning stage for earthquake countermeasures.

The Great East Japan Earthquake occurred on March 11, 2011, it has been reported that many dropped out damage for nonstructural components (ceiling) in a buildings. The fall of ceiling materials is high risk for human damage especially. Large space structures or public gymnasium, etc. must be a safe place, because of it will be used a shelter in a disaster. Therefore, it is important to grasp the seismic performance for nonstructural components such as ceiling. In this study, the basic characteristics of seismic performance for suspended ceiling structure are investigated. In this study, the suspended ceiling structure with improved seismic resistance (earthquake-resistant ceiling structures) using a lightweight steel pipe with caulking is proposed. In this paper, the results of vertical and horizontal loading test are shown, and the mechanical properties of suspended ceiling structure are verified

[synopsis] The Great East Japan Earthquake occurred on March 11, 2011, it has been reported that many dropped out damage for nonstructural components (ceiling) in a buildings. The fall of ceiling materials is high risk for human damage especially. Large space structures or public gymnasium, etc. must be a safe place, because of it will be used a shelter in a disaster. Therefore, it is important to grasp the seismic performance for nonstructural components such as ceiling. In this study, the basic characteristics of seismic performance for suspended ceiling structure are investigated. In this study, the suspended ceiling structure with improved seismic resistance (earthquake-resistant ceiling structures) using a lightweight steel pipe with caulking is proposed. In this paper, the results of vertical and horizontal loading test are shown, and the mechanical properties of suspended ceiling structure are verified.

The bridge bearing is the most important element to support the several loads and ensure the seismic resistance. Recently the deteriorated bearings have been observed remarkably and many of them need to replace. Whereas in the field of seismic design of highway bridge the advanced seismic design code was provided and several seismic reinforcing works were developed for existing bridges, the bridge reinforcements for earthquakes have not been made a progress in the local governments for the reason of poor maintenance budget. The repair work by replacing the deteriorated bearing with seismic-isolation bearing is developed to satisfy the seismic requirement. In this study, optimum design method is developed for seismic-isolation bearing in time of replacing deteriorated bearing in existing bridge. The optimum design problem is formulated to find the size of seismic-isolation bearing considering the constraints related to the fabrication of bearing and performance at ultimate state due to the level 2 earthquakes. The effectiveness and applicability of the method is investigated by applying it to the assumed realistic problem in which the original metal bearing is replaced with the seismic-isolation bearing.

Rainfall reduces the seismic resistance of an embankment if the drainage system of the embankment is inadequate; however, it is not considered in practical seismic design. In this study, a method to consider the effect of rain-fall on the seismic performance of embankments was introduced with the shaking table test results and a case history. A FEM code 'FLIP' with a model of ground strength reduction due to rainfall is described.

The uplift of the flat-bottom cylindrical shell tank has been considered to contribute to the various damage of the tanks. The motion of the free surface and the fluid pressure characterize dynamical effects of the fluid on the tank induced by the uplift motion. Therefore, to properly evaluate the seismic-resistance performance of the tank, account must be made of these behaviors mathematically and numerically. The present paper examines the applicability of the explicit FE-Analysis to numerically compute these behaviors. As we shortly see, the explicit FE-Analysis accurately predicts the motion of the free surface observed during the free rocking test of the tank and the fluid pressure on the tank mathematically derived based on Laplace equation and associate boundary conditions.

The uplift of the flat-bottom cylindrical shell tank has been considered to contribute to the various damage of the tanks. The motion of the free surface and the fluid pressure characterize dynamical effects of the fluid on the tank induced by the uplift motion. Therefore, to properly evaluate the seismic-resistance performance of the tank, account must be made of these behaviors mathematically and numerically. The present paper examines the applicability of the explicit FE-Analysis to numerically compute these behaviors. As we shortly see, the explicit FE-Analysis accurately predicts the motion of the free surface observed during the free rocking test of the tank and the fluid pressure on the tank mathematically derived based on Laplace equation and associate boundary conditions.

From the aesthetic point of view, the construction of a steel bridge pier of a box section with rounded corners was planned. Since its seismic resistance was not thoroughly understood, an experiment of the pier under cyclic horizontal loading was conducted. In the present study, we first confirm a finite element procedure to simulate the experiment with good accuracy. By using this finite element procedure, we conduct the numerical analyses of this type of steel bridge pier to investigate the effects of the slenderness ratio, the axial compressive load and the stiffener rigidity. Based on the numerical results thus obtained, formulas for evaluating the load-carrying capacity and ducitility of this type of steel bridge pier are proposed. The effect of the magnitude of the curvature at the corners is also studied at the end.

This paper summarizes test results and discusses the earthquake-resisting performance, such as lateral strength, ductility and energy absorption capacity, of R/C columns laterally confined by carbon fiber reinforcing plastic tube, namely CFRP tube. The CFRP tubes have the dual function of stay-in-place formwork and transverse reinforcement. In addition to above dual function, CFRP tube is light and is hardly likely to corrode, namely its durability is superior. As the transverse bending stiffness of the wall of CFRP square tube is likely to be lack, it must be examine that transverse expansion or deflection happen or do not due to lateral pressure by fresh concrete under construction of test specimens. However, circular CFRP tubes are not concerned with its problem. Although CFRP tubes are not structural members by themselves, they will turn into important seismic resistance member by the combination of CFRP tubes and conventional R/C columns.\nTotal four column specimens are provided and their column sections are square type only. The specimens whose sizes are 250 mm square and 1000 mm height are about one-third or half scale model. Therefore, shear span to depth ratio is 2.0. Concrete cylinder strength is about 32 MPa and longitudinal reinforcement ratio, namely, ratio of total area of longitudinal reinforcement to gross area of section in columns is 2.44% which is close to the upper limit. These R/C column specimens were tested under the combination of cyclic lateral forces and constant axial load in order to investigate their seismic behavior.\nAs a result of this study, the advantages of the CFRP tubes were recognized. Therefore, if the cost of the CFRP tube will be degraded in the near future, this proposed method will be widely accepted in the field of hybrid concrete structures., 紀要論文

Slope failures on a lifeline such as expressway were observed in Japan Mid Niigata earthquake 2004 and Noto Hanto earthquake 2007. However, it is not realistic to check the seismic performance of component of a lifeline. It is important how to pick up relatively weak section in terms of seismic resistance. In this study, a practical seismic evaluation method of slopes was proposed by reviewing previous studies by the authors. The proposed method enables a rational slope stability assessment of a lifeline.

Slope failures on a lifeline such as expressway were observed in Japan Mid Niigata earthquake 2004 and Noto Hanto earthquake 2007. However, it is not realistic to check the seismic performance of component of a lifeline. It is important how to pick up relatively weak section in terms of seismic resistance. In this study, a practical seismic evaluation method of slopes was proposed by reviewing previous studies by the authors. The proposed method enables a rational slope stability assessment of a lifeline.

A stone construction like a lantern and a gravestone is a simple unstable structure which stacked stones. So the damage of a stone lantern caused by the earthquake has occurred mostly. It is necessary to take the prevention from a fall of a lantern into consideration because the fall of a lantern is very dangerous. In this study, we estimate the seismic performance of a stone lantern using 3-D DEM analysis and real scale shaking table test, and evaluate the seismic resistance of the reinforced lantern. As the result, the seismic performance of the stone lantern was able to be evaluated by the shaking table test and 3-D DEM analysis. It was able to evaluate that the reinforced lantern was effective against the earthquake motion by experiment. The proposal of the suitable reinforcement against the earthquake was estimated. 日本は大規模災害となるような地震が多く発生する地域であり，近年も東北地方太平洋沖地震をはじめ大規模な地震災害が頻発している．それに伴う石造構造物の被害も多く発生しており，特に灯篭や墓石は石材を積み重ねた単純な不安定構造物であることから，多くの被害を受けている．墓石に関しては，兵庫県南部地震を契機に様々な補強方法の考案や検証が行われてきたが，灯篭に関しての耐震対策の検証は現状ほとんど行われていない．そこで，今回は石灯篭に着目し，無補強と有補強の石灯篭に対して地震時応答特性と耐震補強方法について実験的研究と解析的研究を行った．石灯篭に心棒を通す補強法をとったが，振動台実験や解析結果から，本方法は灯篭の倒壊防止に有効な対策となることがわかった．, 出版者照会後に全文を公開

This experimental study is made to investigate the effect of diagonal reinforcement arrangementon the seismic resistance of reinforced concrete columns having conventional parallel reinforcementand diagonal reinforcement. Variables chosen for experiments are diagonal reinforcement ratioβ, which is the ratio of the amount of diagonal tension reinforcement to that of total tension rein-forcement.It is noted that the load carrying capacity and energy dissipation capacity of columns increaseswith the increase of the diagonal reinforcement ratio without adding extra amount of shear rein-forcement, and that the columns with the diagonal reinforcement ratio β being 0.6 have the satisfac-tory seismic performance. It is additionally shown that the analysis for ultimate strength of columnswith mixed use of conventional parallel and diagonal reinforcement make use of the so-calledextended additive strength theory based upon the beam, arch and truss mechanism concept. It isrecognized that the ultimate strength of columns can be estimated with a sufficient accuracy by theanalysis.