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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第3期7卷 430-435页

作者：车爱兰 iwatate takahiro 葛修润 School of Naval Architecture Ocean and Civil Engineering Shanghai Jiao Tong University Shanghai 200030 China Civil and Environmental Engineering Tokyo Metropolitan University Tokyo 192-0397 Japan

A series of scaled-model shaking table tests and its simulation analyses using dynamic finite element method were performed to clarify the dynamic behaviors and the seismic stability of embedded corrugated steel culverts due to strong earth-quakes like the 1995 Hyogoken-nanbu earthquake. The dynamic strains of the embedded culvert models and the seismic soil pressure acting on the models due to sinusoidal and random strong motions were investigated. This study verified that the cor-rugated culvert model was subjected to dynamic horizontal forces (lateral seismic soil pressure) from the surrounding ground, which caused the large bending strains on the structure; and that the structures do not exceed the allowable plastic deformation and do not collapse completely during strong earthquake like Hyogoken-nanbu earthquake. The results obtained are useful for design and construction of embedded long span corrugated steel culverts in seismic regions.

关键词： Embedded corrugated steel culverts Shaking table tests Hyogoken-nanbu earthquake Dynamic analyses

Evaluation of Dynamic Soil-Structure Interaction and Dynamic Seismic Soil Pressures Acting on It Subjected to Strong Earthquake Motions

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Journal of Shanghai Jiaotong university(Science) 2006年第4期11卷 530-536页

作者：车爱兰 iwatate takahiro 葛修润 School of Naval Architecture Ocean and Civil Eng. Shanghai Jiaotong Univ. Civil and Environmental Eng. Tokyo Metropolitan Univ.

In order to clarify the damage mechanism of the subway structure, the dynamic soil-structure interaction and the dynamic forces acting on the structure, a series of shaking table tests and simulation analyses were performed. The seismic response of the structure and the dynamic forces acting on the structure due to sinusoidal and random waves were investigated with special attention to the dynamic soil-structure interaction. The result shows that the compression seismic soil pressures and extension seismic soil pressures simultaneously act on the sidewalls, and big shear stress also acts on the ceiling slab due to horizontal excitation. The seismic soil pressure could be approximated to hyperbola curve, and reached a peak value with increase of the shear strain of the model ground. In addition, a slide and exfoliation phenomenon between the structure and the surrounding ground was simulated, using the nonlinear analyses. The foundation is provided for amending the calculation method of seismic soil pressure and improving the anti-earthquake designing level of underground structure.

关键词： subway structure dynamic seismic soil pressure dynamic soil-structure interaction shaking table tests dynamic analyses nonlinear characteristics

Study on the applicability of frequency spectrum of micro-tremor and dynamic characteristics of surface ground in Asia area

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第11期7卷 1856-1863页

作者： CHE Ai-lan iwatate takahiro ODA Yoshiya GE Xiu-run School of Naval Architecture Ocean and Civil Engineering Shanghai Jiao Tong University Shanghai 200030 China Department of Civil and Environmental Engineering To~o Metropolitan University Tokyo 192-0397 Japan Department of Civil Engineering Xi ＇an Jiaotong Universitv Xi ＇an 710049. China

The dynamic characteristics of ground soil using micro-tremor observation in Asia (Zushi and Ogasawara (Japan), Xi’an (China), Manila (Philippines), and Gujarat (India)) are studied. Ground micro-tremor signals were observed and analyzed by fast Fourier transform method (FFT). The response of ground soil to frequency of ground micro-tremor is revealed, and func- tions with frequency-dependence and frequency-selection of micro-tremor for different foundation soil strata are also researched. The horizontal to vertical spectral ratio (H/V, Nakamura technique) of micro-tremor observed at the surface ground was used to evaluate the site’s predominant period. This paper also discusses the application of micro-tremor on site safety evaluation, and gives the observed calculation results obtained at multiple points. The experimental foundation and the deduction process of the method are described in detail. Some problems of the method are pointed out. Potential use of the technique’s good expandable nature makes it a useable means for preventing and reducing disaster’s harmful effects.

关键词： Micro-tremor observation Nakamura method Predominant period Earthquake observation Spectral analysis

The Seismic Characteristics of Surface Ground of Zushi-Site during the 2011 off the Pacific Coast of Tohoku Earthquake

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Journal of Geological Resource and Engineering 2014年第4期2卷 208-216页

作者： takahiro iwatate Nobuyuki Naito Koji Ando Yoshiya Oda Professor Emeritus Department of Civil Engineering Graduate School of Engineering Tokyo Metropolitan University ~ SeniorResearch Adviser Chishitsu Keisoku Co. Ltd 1-1Minamiosawa Hachioji Tokyo 192-0397 Japan ARK Information Systems Inc. 3-22-17 Shinyokohama Kohoku-ku Yokohama 222-0033 Japan Vibrant System Development Co. Ltd. 5-39-16 Nangai Higashiyamato-shi Tokyo 207-0014 Japan Department of Civil and Environmental Engineering Tokyo Metropolitan University 1-1Minamiosawa Hachioji Tokyo192-0397Japan

In Tokyo Metropolitan University, the horizontal and vertical array earthquake observations has begun in June 1994 at the five stations （kl-k5） on the ground surface and bedrock （k6：-30 m depth） at Zushi-site. More than 200 medium and small earthquakes with the magnitude 5.0-7.3 were recorded between 1994 and 2012. At the 2011 off the Pacific coast of Tohoku Earthquake （EQ.3.11 M = 9.0）, the largest surface ground acceleration （kl = 124.5 gal, k6 = 45.5 gal） of the horizontal component was recorded. Main results were obtained as follows：（1） the surface ground motion characteristics of Zushi-site were examined using the observed data （kl ＆ k6） of EQ.3.11, the past-observed smaller earthquakes （EQ.1 ＆ EQ.10.08） and aftershock （EQ.12.3）, respectively. The non-liner seismic response characteristics of the surface ground at Zushi-site were verified during EQ.3.11. （2） The ground structure models were examined and identified by the modal analyses and the FEM （finite element method） identification analyses using the observed acceleration data of EQ.3.11 and the past observed smaller earthquakes. （3） Moreover, the three dimensional seismic response analyses were performed by TDAPUl （time domain 3-dimensional dynamic analysis program）, using k6 for input motions and identified ground structure model, and evaluated the dynamic behaviours of the surface ground. The calculated results agreed well with the observed ones.

关键词： The 2011 offthe Pacific coast of Tohoku earthquake Zushi-site earthquake observation identification analysis seismic response analysis.

地下大断面薄钢结构地震响应的试验研究及数值分析

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岩石力学与工程学报 2006年第z2期25卷 4052-4058页

作者：车爱兰岩楯敞广葛修润上海交通大学船舶海洋与建筑工程学院上海200030 首都大学东京都市环境学部

为明确地下大断面薄钢结构的安全实用性,进行1/16大断面薄钢结构的系列模型振动试验、实际规模结构的现场试验和有限元分析。在把握作用于模型的地震动土压力及结构的应变状况的基础上,对施工过程中结构的响应特性及土压力的变化等进行... 详细信息

为明确地下大断面薄钢结构的安全实用性,进行1/16大断面薄钢结构的系列模型振动试验、实际规模结构的现场试验和有限元分析。在把握作用于模型的地震动土压力及结构的应变状况的基础上,对施工过程中结构的响应特性及土压力的变化等进行研究。明确地下大断面薄钢结构的地震及施工时的安全性,为今后大断面薄钢结构的设计、施工提供依据。

关键词：结构力学地下大断面薄钢结构模型振动试验现场试验阪神?淡路大地震有限元分析

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关于地铁地震响应的模型振动试验及数值分析

岩土力学 2006年第8期27卷 1293-1298页

作者：车爱兰岩楯敞广葛修润上海交通大学船舶海洋与建筑工程学院上海200030 首都大学东京都市环境学部

为明确大地震时地铁的破坏过程及原因,以1995年日本阪神-淡路大地震中遭受严重破坏的神户大开地铁车站为对象,进行了一系列的模型振动试验和动力有限元分析。对于作用于地下结构的地震动土压的发生原理、地震波输入方向、结构的埋设深... 详细信息

为明确大地震时地铁的破坏过程及原因,以1995年日本阪神-淡路大地震中遭受严重破坏的神户大开地铁车站为对象,进行了一系列的模型振动试验和动力有限元分析。对于作用于地下结构的地震动土压的发生原理、地震波输入方向、结构的埋设深度、地基与结构间的刚性比对地震动土压的影响及在地基-结构系统的非线性响应下结构周围地基终局状态时的地震动土压进行了研究。明确了地震动土压的极限值及在大地震时周围地基的残余应变引起的静止土圧力的存在。为今后改进地震土压力计算方法、提高地下结构抗震设计水平提供了依据。

关键词：阪神-淡路大地震模型振动试验动力有限元分析:地震动土压地震响应

Prospective real-time evaluation of diagnostic performance using endocytoscopy in differentiating neoplasia from nonneoplasia for colorectal diminutive polyps(≤ 5 mm)

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World Journal of Gastrointestinal Oncology 2018年第4期10卷 96-102页

作者： takahiro Utsumi Yasushi Sano Mineo iwatate Hironori Sunakawa Akira Teramoto Daizen Hirata Santa Hattori Wataru Sano Noriaki Hasuike Kazuhito Ichikawa takahiro Fujimori Gastrointestinal Center and Institute of Minimally Invasive Endoscopic Care (iMEC) Sano Hospital Department of Pathology Shinko Hospital

AIM To clarify the diagnostic performance of endocytoscopy for differentiation between neoplastic and nonneoplastic colorectal diminutive *** Patients who underwent endocytoscopy between October and December 2016 at Sano Hospital were prospectively recruited. When diminutive polyps(≤5 mm) were detected, the lesions were evaluated by endocytoscopy after being stained with 0.05% crystal violet and 1% methylene blue. The diminutivepolyps were classified into five categories(EC 1 a, 1 b, 2, 3 a, and 3 b). Endoscopists were asked to take a biopsy from any lesion diagnosed as EC1 b(indicator of hyperplastic polyp) or EC2(indicator of adenoma). We have assessed the diagnostic performance of endocytoscopy for EC2 and EC1 b lesions by comparison with the histopathology of the biopsy specimen. RESULTS A total of 39 patients with 63 diminutive polyps were analyzed. All polyps were evaluated by endocytoscopy. The mean polyp size was 3.3 ± 0.9 mm. Among the 63 diminutive polyps, 60 were flat and 3 were pedunculated. The mean time required for EC observation, including the time for staining with crystal violet and methylene blue, was 3.0 ± 1.9 min. Histopathologic evaluation showed that 13 polyps were hyperplastic and 50 were adenomas. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of EC2 for adenoma compared with EC1 b for hyperplastic polyp were 98.0%, 92.3%, 96.8%, 98.0% and 92.3%, respectively. There were only two cases of disagreement between the endoscopic diagnosis made by endocytoscopy and the corresponding histopathological *** Endocytoscopy showed a high diagnostic performance for differentiating between neoplastic and non-neoplastic colorectal diminutive polyps, and therefore has the potential to be used for "real-time histopathology".

关键词： Endocytoscopy Diagnostic performance Diminutive polyp Endocytoscopic classification Realtime histopathology

Narrow-band imaging observation of colorectal lesions using NICE classification to avoid discarding significant lesions

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World Journal of Gastrointestinal Endoscopy 2014年第12期6卷 600-605页

作者： Santa Hattori Mineo iwatate Wataru Sano Noriaki Hasuike Hidekazu Kosaka Taro Ikumoto Masahito Kotaka Akihiro Ichiyanagi Chikara Ebisutani Yasuko Hisano takahiro Fujimori Yasushi Sano Gastrointestinal Center and Institute of Minimally Invasive Endoscopic Care Sano Hospital Department of Gastroenterology Kobe Minimally Invasive Treatment Center of Cancer Medical Oncology/Hematology Kobe University Graduate School of Medicine Department of Pathology Shinko Hospital

AIM: To assess the risk of failing to detect diminutive and small colorectal cancers with the "resect and discard" ***: Patients who received colonoscopy and polypectomy were recruited in the retrospective study. Probable histology of the polyps was predicted by six colonoscopists by the use of NICE classification. The incidence of diminutive and small colorectal cancersand their endoscopic features were assessed. RESULTS: In total, we found 681 cases of diminutive(1-5 mm) lesions in 402 patients and 197 cases of small(6-9 mm) lesions in 151 patients. Based on pathology of the diminutive and small polyps, 105 and 18 were non-neoplastic polyps, 557 and 154 were low-grade adenomas, 18 and 24 were high-grade adenomas or intramucosal/submucosal(SM) scanty invasive carcinomas, 1 and 1 were SM deeply invasive carcinoma, respectively. The endoscopic features of invasive cancer were classified as NICE type 3 ***: The risk of failing to detect diminutive and small colorectal invasive cancer with the "resect and discard" strategy might be avoided through the use of narrow-band imaging observation with the NICE classification scheme and magnifying endoscopy.

关键词： Image-enhanced endoscopy Narrow-band imaging Resect and discard NICE classification Magnifying endoscope Colonoscopy SM-d