|
|---|
Associate Professor Rick Henry from the University of Auckland visited the Department of Civil Engineering, Tsinghua University on January 05, 2024. He shared the development and research of low-damage structural systems and introduced a 2-storey precast concrete building shaking table test. The test building used a combination of post-tensioned walls and a fame that utilized slotted beam connections and was subjected to both unidirectional and bi-directional ground motions. Key outcomes related to the system response of the test building and subsequent analysis are discussed including deformation compatibility and damage when subjected to both unidirectional and bi-directional ground motions, the performance of different wall-to-floor and non-linear structural models used to further understand the system-level response and overstrength of the test building. Additional related research projects will also be discussed including: Residual capacity and repair of RC walls, retrofitting precast concrete floors, steel beam to concrete wall connections, and system response of coupled walls. Furthermore, the students of Prof. Ji's group presented their recent research work in turn and engaged in discussions, Associate Professor Rick Henry also provided many valuable suggestions regarding the research work of Prof. Ji's group.
|  |
|
|---|
During 21-26 August 2023, a large-scale experimental test on seismic behavior of RC core wall substructure was carried out by Professor Ji’s group using the 10,000 tonf-capacity multi-functional testing facility (the world’s largest spatial loading equipment) in the lab of China Construction Industrial Engineering and Technology Research Academy Co. Ltd. (CCIETRA). The prototype structure is the bottom core wall of a high-rise building designed per Chinese code (PGA = 0.2g for design basis earthquake). The geometric size of the test specimen is 4 m × 3 m × 8.6 m, and the thickness of the wall piers is 150 mm and 180 mm in X and Y directions, respectively. During the test, 3-D and 6-DOF controlled loading is applied on the test specimen. The following issues are focused on: (1) the spatial resisting mechanism and seismic design of the core wall under high axial compression force and bidirectional loading; (2) Coupled tension-flexure-shear behavior of wall piers in tension with an average nominal tensile stress larger than ftk, and shear redistribution among wall piers caused by the degradation of shear stiffness of wall piers in tension.
|  |
|
|---|
On August 23, 2023, the Symposium of Advance in Experiments and Modelling of Seismic Performance of Building Structures has been held in New Civil Engineering Building 200B, Department of Civil Engineering, Tsinghua University. The meeting was co-chaired by Associate Professor Xiaodong Ji of Tsinghua University and Associate Professor Asai of the University of Tokyo. The members of Prof. Xiaodong Ji group from Tsinghua University, Dr. Fujiwara, Dr. Nishi from NIED, and the member of Prof. Nagae group from Nagoya University have attended the symposium. A total of eight presentations were arranged in this symposium. During the meeting, professors and students have conducted in-depth exchanges and extensive discussions on the latest research progress of their groups. The symposium was held successfully in achieving its objective.
|  |
|
|---|
On September 9 to 10, 2021, a TVMD coupled wall substructure test was carried out in IEM Huixian laboratory of earthquake engineering. The test model was a 1:3 scaled 3-story substructure taken from a TVMD coupled wall system in a high-rise building. The width of the model is about 4.0 m and the height is about 5.6 m. The two wall piers in the model were connected by three brace-type TVMDs in a zig-zag configuration. The test was conducted by applying dynamic loadings to the model by a high-performance actuator. In this test, the performance of TVMD coupled wall substructure was obtained based on the structural response measurement under dynamic loadings. This test is an general experimental validation of the newly proposed brace-type TVMD, TVMD coupled wall system as well as the design theory and has been successfully accomplished.
|  |
|
|---|
On March 14, 2021, a three-story RC shear wall frame structure shake-table test was carried out in the shake-table laboratory of the China Academy of Building Research. The purpose of the test was to verify the computer vision-based RC structure seismic damage identification technology and residual seismic capacity evaluation method. The scale of the model was 1:2, with a length of 4.7 m, a width of 3 m, and a story height of 2.3 m. In the longitudinal direction, shear walls coupled to corner columns by slab beams were used, whereas in the transverse direction, a one-bay moment frame system was used.
In the test, high-quality photos of the damaged components were obtained, and they can be used to evaluate the degradation of the mechanical properties of the damaged components and the residual seismic capacity of the structure. After that, we can compare the evaluation results with the dynamic response and the system identification results. The test recorded the whole process of the structure from intact status to severely damaged status, and provided valuable test data.
|  |
|
|---|
From May 23 to 24, 2019, the International Symposium of Advancement in Earthquake Engineering and Seismic Design was held in Department of Civil Engineering, Tsinghua University. Assoc. Prof. Xiaodong Ji from Tsinghua University and Prof. Taichiro Okazaki from Hokkaido University chaired the seminar. The meeting was partially supported by NSFC-JSPS collaborative research project.
Prof. Taichiro Okazaki from Hokkaido University, Prof. Ippei Maruyama and Assoc. Prof. Takuya Nagae from Nagoya University, Assoc. Prof. Noriyuki Takahashi from Tohoku University, Prof. Peng Pan, Assoc. Prof. Zuozhou Zhao and Assoc. Prof. Xiaodong Ji from Tsinghua University, Prof. Tao Wang and Prof. Xuchuan Lin from the Institute of Engineering Mechanics of China Earthquake Administration (IEM), as collaborative project members, and Assoc. Prof. Ryota Matsui from Hokkaido University, Assoc. Prof. Yao Cui from Dalian University of Technology and Assist. Prof. Shelly Zhang from UIUC attended the symposium and gave presentations. Graduate students from Tohoku University, Tsinghua University, IEM, Dalian University of Technology and Tianjin University participated in the seminar. During the meeting, professors and students from China, Japan, and the United States discussed in depth. The conference promoted exchanges and cooperations among young scholars in the field of international earthquake engineering and achieved great success.
On the morning of May 24th, the symposium specially set up an engineer section. The meeting invited Engineering Director of Nikken Sekkei (Osaka) Dr. Kato, Associate Manager of Structural Engineering Section of Nikken Sekkei (Osaka) Mr. Yamada, senior engineer Lijun Wang and Weibiao Yang, gave reports. President of the International Association of Earthquake Engineering, Prof. Masayoshi Nakashima, attended the symposium through remote video. In the symposium, scholars from China and Japan exchanged opinions on the integration of architectural and structural design in Japan, and the design and construction of super high-rise buildings in China.
On May 25, the symposium organized a construction site tour. Nearly 20 scholars and students from China and Japan participated in the technical tour. In the morning, the group visited three high-rise buildings of about 200m in Beijing Lize Business District. Among them, two buildings are core wall-frame system with CFTs and outrigger truss, and the other is core wall-frame system with SRCs. In the afternoon, the group visited the construction site of the Chinese National Speed Skating Oval, “the Ice Ribbon”. The National Speed Skating Oval is the only new-constructed competition venue for the Beijing Winter Olympics in 2022. The main structure in the bottom is RC structure, and the roof system is a cable net tension structure. During the project tour, scholars from China and Japan exchanged views on the structural systems and design methods of high-rise buildings in China and Japan. China's innovative practices in the design and construction of high-rise buildings and large-span structures left a deep impression on Japanese scholars.
|  |
|
|---|
On the morning of May 23, 2019, the Japanese team members of the NSFC-JSPS collaborative research project visited Tsinghua University. The project members of both Chinese and Japanese sides launched a particular discussion on the topic of “Assessment of seismic damage and performance of building structures using artificial intelligence and computer vision techniques.” In the beginning, PI of Chinese-side, Assoc. Prof. Xiaodong Ji from Tsinghua University and PI of Japanese-side, Prof. Taichiro Okazaki from Hokkaido University introduced the overall progress of the project in each side. Subsequently, Assoc. Prof. Noriyuki Takahashi, graduate student Hiroyuki Chida and Yuki Mimizuka from Tohoku University, graduate student Zenghui Miao and undergraduate student Yucheng Zhuang from Tsinghua University reported recent works in the research of damage identification and crack quantification. The representatives exchanged opinions on relevant technical details and discussed future research topics and cooperation options.
|  |
|
|---|
On October 12, 2018, the Symposium of Recent Advancement in Earthquake Engineering has been held in He Shanheng Building, Department of Civil Engineering, Tsinghua University. The meeting was co-chaired by Professor Peng Pan and Associate Professor Xiaodong Ji of Tsinghua University. Professor Emeritus of Kyoto University, Honorary Professor of Tsinghua University, Masayoshi Nakashima, Prof. Peng Pan, Prof. Xiaodong Ji and Prof. Gang Shi from Tsinghua University, Prof. Tao Wang, Prof. Xuchuan Lin from IEM, Prof. Zhenyun Tang from Beijing University of Technology, Prof. Qiang Xie, Prof Liusheng He from Tongji University, Prof. Yundong Shi, Prof Yunbiao Luo from Tianjin University, Prof. Xiaohua Li from Chongqing University, Prof. Yao Cui from Dalian University of Technology have attended the meeting. More than 40 teachers and students have participated the seminar. During the meeting, professors has conducted in-depth exchanges and heated discussions on the latest research progress of their groups. The meeting has promoted the exchanges and cooperation between young scholars in the field of earthquake engineering in China and has achieved great success.
|  |
|
|---|
On October 8, 2018, Professor Emeritus of Kyoto University, Japan, Masayoshi Nakashima visited the Department of Civil Engineering. A seminar was held to introduce the ongoing research of Prof. Ji's Group, Prof. Nakashima presented valuable opinions and long-term suggestions on the research work. Professor Masayoshi Nakashima is a member of the Engineering Academy of Japan, a foreign member of the National Academy of Engineering of the U.S., and a corresponding member of the Mexican Academy of Engineering. He visited Tsinghua University and was appointed as an honorary professor at Tsinghua University. Professor Masayoshi Nakashima is a well-known scholar in the field of international earthquake engineering. He has made important contributions to promoting the exchanges and cooperation between the Department of Civil Engineering of Tsinghua University and the academia, industry of Japan and the U.S. in the field of earthquake engineering.
|  |
|
|---|
On September 20, 2018, Prof. Ikago of Tohoku University visited the Department of Civil Engineering in Tsinghua University, and gave a presentation about tuned viscous mass damper .Prof. Ikago and Prof. Ji introduced their latest research about TVMD. In the end, Prof. Ji discussed his research plan about TVMD with Prof. Ikago and other audience.
|  |
|
|---|
On September 3, 2018, Dr. Rolands of Nottingham Trent University visited the Department of Civil Engineering of Tsinghua University, and gave a presentation titled "Characterizing and interpreting thermal response of bridges and Measuring structural deformations using smartphones". Professors Xiaodong Ji, Zhang chonghou, Zhao zuozhou and postgraduates of the Department of Civil Engineering of Tsinghua University participated in this presentation and discussed the related contents with Dr. Rolands. The lecture is comprised of two parts, and Dr. Rolands introduced us to some of his achievements in the field of structural health monitoring. In the first part, based on the nonlinear regression model, Dr. Rolands proposed the regression-based thermal response prediction methodology of bridge structure. The effectiveness of the method is verified by experiments. The application is demonstrated in multi-span continuous beam bridge for damage detection. The second part of the lecture focused on the displacement measurement method based on smartphone images and videos. Examples of the method on static, quasi-static and dynamic tests are presented, and application of real-world bridges for displacement monitoring is illustrated. In addition, a study of multi-epoch imaging approach to collect accurately structural displacements when capturing images of a structure from different positions is introduced.
|  |
|
|---|
Prof. Carlos Molina Hutt from the University of British Columbia visited Prof, Ji's research group on July 11th 2018. Prof. Carlos Molina Hutt gave a presentation based on his research about the evaluation of post-earthquake recovery ability for structures. The contents about how to quantify expected seismic performance, evaluate strategies for enhanced seismic performance and benchmark performance against modern designs were introduced. And a possible extend framework beyond individual building evaluations was discussed. Prof. Ji's group members introduced their latest research, discussed with Prof. Carlos Molina Hutt and got many valuable suggestions.
|  |
|
|---|
An international symposium was held to introduce the recent advancement and new technologies in earthquake engineering developed by each individual presenter. The main objective of this symposium is to enable the project members to be familiar with each other, to understand the ongoing research for each other, and to expand future broad collaboration. Approximately 40 researchers and students from Tsinghua University and IEM participated in this symposium. Adequate discussions were observed among the presenters and audiences. The workshop was held successfully in achieving its objective.
|  |
|
|---|
A seminar was held to introduce the ongoing research of Prof. Ji's group. Three research topics were presented. 1) Mr. Xiaowei Cheng (Ph.D. student) and Mr. Mengchao Xu (master student) presented the complicated behavior of RC shear walls subjected to combined tension, bending and shear loads. 2) Mr. Junshan Zhang (master student) and Mr. Yuhao Cheng (Ph.D. student) presented the development of an innovative shear wall system for enhanced seismic resiliency of high-rise buildings. The new system is named tuned viscous mass damper (TVMD) coupled wall system. 3) Dr. Sanjukta Chakraborty (postdoctoral researcher) shared her latest work on development of control algorithms for substructure shaking table tests. During the seminar, Prof. Okazaki, Prof. Takahashi and Prof. Marino kindly delivered their comments and suggestions to the presenters for these ongoing studies.
|  |
|
|---|
The team members from both China and Japan sides held a technical discussion with the theme of "Rapid Post-Quake Estimation of Structural Damage and Performance Based on Modern Image Processing Technology". The key words of the meeting were image processing and performance evaluation. Mr. Zenghui Miao (a Ph.D. student of Prof. Ji) presented his work on “Damage evaluation of RC structural components based on modern image processing and deep learning”. Dr. Xiaoting Wang (a postdoctoral researcher in Prof. Pan's group) presented the latest work on new Chinese code drafting on resilience assessment of buildings, including assessment procedure and the software for calculation of repair cost and time. Prof. Takahashi gave a brief introduction on the researches of his group. Afterwards, the participants discussed research ideas and technical difficulties of the imaging processing, crack quantification, damage identification and performance evaluation. The PEER-Hub competition of imaging-based damage identification was discussed as well.
|  |
|
|---|
Doc. Rick Henry from the University of Auckland visited the Department of Civil Engineering, Tsinghua University on April 18, 2018. He gave a comprehensive and wonderful presentation titled “Design of Seismic Resilient Concrete Buildings in New Zealand”. The presentation provided an overview of recent earthquakes in New Zealand and key lessons from these earthquakes. This talk also presented test research and design practice to achieve low-damage concrete buildings (e.g. Post-tensioned rocking wall). At last, Prof. Rick Henry shared the design details of Post-tensioned rocking wall (e.g. wall-to-floor connection, wall-to-column connection). Doc. Rick Henry will take part in Prof. Ji's reasearch on the axial tesion-shear coupled behavior of RC shear walls in the future.
|  |
|
|---|
2017年11月4日，大连理工大学结构工程专业崔瑶副教授课题组与清华大学纪晓东副教授课题组
在清华大学共同开展了一场联合组会，参与此次活动的还有清华大学部分本科生。
此次活动旨在通过双方学生的课题展示与交流讨论，进一步促进两校之间形成良好的学术交流与科研合作氛围，
有助于双方研究生取长补短、开拓思维、争相创新，有效提高研究生的科研水平。
|  |
|
|---|
2017年6月28日，日本东京工业大学（Tokyo Institute of Technology）Shoichi Kishiki教授、罗马尼亚土木工程技术大学（Technical
University of Civil Engineering Bucharest (UTCB)）Andreea
Dutu讲师、大连理工大学崔瑶副教授以及中国地震局工程力学研究所曲哲研究员到访课题组，开展学术交流活动。Andreea Dutu讲师做了题为“Traditional Romanian Timer
Frames with Infills”的学术报告，崔瑶副教授做了题为“Experimental Study on Seismic Behavior of Roof
Joint”的学术报告。课题组成员也汇报了近期科研工作，并得到了四位来访学者的评价和建议。
|  |
|
|---|
2017年6月1日，加拿大麦克马斯特大学（McMaster University）的Dimitrios Konstantinidis副教授和Tracy
Becker副教授到访课题组，课题组师生依次介绍了近期科研工作，并与两位副教授进行了讨论，Dimitrios Konstantinidis副教授和Tracy
Becker副教授就课题组的研究工作提出了许多宝贵的意见和建议。
|  |
|
|---|
2017年5月4日，清华大学土木工程系举办了结构抗震和功能可恢复研讨会。与会人员有日本京都大学Masayoshi Nakashima教授，美国密歇根大学Jason P.
McCormick教授，清华大学钱稼茹教授、潘鹏课题组、施刚课题组及纪晓东课题组，中国地震局工程力学研究所王涛课题组、林旭川课题组，北京工业大学唐贞云课题组。会上，Nakashima教授分享了自己早年求学的经历，并做了题为“How
to Make A Presentation”的报告，指导现场的后辈学子如何更好的进行学术汇报。纪晓东课题组的刘丹、梁东星和程小卫先后上台做学术报告。
|  |
|
|---|
美国密歇根大学（University of Michigan）副教授Jason P.
McCormick到访课题组，开展了学术交流活动。课题组师生依次汇报了近期科研工作，McCormick副教授对课题组成员们的成果做出了评价，并提出了自己的看法和建议。
|  |
|
|---|
英国布拉德福德大学（University of Bradford）教授Dennis
Lam到访课题组。课题组师生汇报了近期科研工作，并与Lam教授展开了热烈的讨论，Lam教授就课题组汇报内容提出了很多宝贵的意见和建议。
|  |
|
|---|
日本东北大学（Tohoku University）教授Kohju Ikago来访。上午，Ikago教授和纪晓东副教授交流分享了各自课题组的研究内容和成果；下午，两方就合作项目做了进一步交流。 |  |
|
|---|
昆士兰大学（The University of Queensland）教授、澳大利亚工程院院士Sritawat
Kitipornchai来访，课题组同学汇报了近期科研工作，Kitipornchai教授对同学们的研究工作提出了相关建议和指导。
|  |
|
|---|
英国帝国理工大学（Imperial College）教授、英国皇家工程院院士David Nethercot来访，课题组同学汇报了近期科研工作，Nethercot教授对同学们提供了学术指导和建议。
|  |
|
|---|
2016年6月28日，震后功能可恢复结构研讨会在清华大学土木工程系召开。会上，纪晓东课题组与日本东京工业大学（Tokyo Institute of Technology）吉敷祥一(Shoichi
Kishiki)教授、中国地震局工程力学研究所曲哲课题组和北京工业大学乔琦云课题组进行了学术交流和汇报，总结功能可恢复结构的最新进展，讨论开展学术合作。
|  |
|
|---|
日本科学院院士Akira
Wada教授来访，并在清华大学进行了为期5天的“塑性分析与基于损伤控制的结构抗震设计”短期课程，重点介绍了塑性分析理论和损伤控制设计理论，讲授如何将设计理论应用于抗震结构、隔震结构和消能减震结构。课程结束后课题组同学汇报了近期科研工作，Wada教授对同学们提供了学术指导和建议。
|  |
|
|---|
以色列理工学院（Technion – Israel Institute of Technology）副教授Oren Lavan来访，带来了题为“Optimal Seismic Retrofitting
and Design of Buildings Using Energy Dissipation
Devices”的学术讲座，重点介绍了运用各种阻尼器进行结构加固的优化设计方法。课题组学生汇报了近期科研工作，并与Oren Lavan探讨了课题组未来的研究方向。
|  |
|
|---|
上海力岱结构工程技术有限公司(Lead Dynamic Engineering Co., Ltd.)的副董事长白井贵志先生及董事会成员贺明玄先生来访，介绍了该公司的产品，包括防屈曲支撑Unbonded
Brace(UBB)、U型隔震阻尼器U-Damper和粘弹性阻尼器VE-Damper，并与师生进行了交流。
|  |
|
|---|
Akira Wada教授来访，课题组同学汇报了近期科研工作，Wada教授对科研工作的创新和存在的问题提供了指导建议。 |  |
|
|---|
日本京都大学和东京工业大学研究生来访，与课题组同学展开学术交流，相互汇报了近期科研成果，并就科研工作中存在的问题相互交换了看法。 |  |
|
|---|
日本东京工业大学Toru Takeuchi教授来访并展开学术活动，Takeuchi教授作了题为“Seismic Design with Energy-control
Concepts”的学术讲座，介绍了基于能量控制的抗震设计概念及其在新建建筑及已有建筑加固改造中的应用。
|  |
