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Frontiers of Structural and civil eng.neering 2017年第3期11卷 322-328页

作者： Wenjuan SUN Linbing WANG Yaqiong WANG USTB-Virginia Tech Joint Lab on Multifunctional Materials National Center for Materials Service Safety University of Science and Technology Beijing Beijing China Virginia Tech Blacksburg VA 24061 United States Shaanxi Provincial key laboratory for Highway Bridge & Tunnel Chang'an University Xi'an 710064 China

Mechanical properties of rock materials are related to textural characteristics. The relationships between mechanical properties and textural characteristics have been extensively investigated for differently types of rocks through experimental tests. Based on the experimental test data, single- and multiple- variant regression analyses are conducted among mechanical properties and textural characteristics. Textural characteristics of rock materials are influenced by the following factors： mineral composition, size, shape, and spatial distribution of mineral grains, porosity, and inherent microcracks. This study focuses on the first two： mineral composition and grain size. This study comprehensively summarizes the regression equations between mechanical properties and mineral content and the regression equations between mechanical properties and grain size. Further research directions are suggested at the end of this study.

关键词： Mechanical properties rock material texture mineral characteristics

Seismic behavior of concrete filled steel tubular arch structures

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Earthquake eng.neering and eng.neering Vibration 2005年第1期4卷 107-115页

作者：熊峰 Sashi K Kunnath 刘浩吾 Dept. of civil eng.neering Sichuan University Chengdu 610065 ChinaProfessor Dept. of civil and Environmental eng.neering California University at Davis CA95616 USAProfessor Dept. of hydraulic eng.neering Sichuan University Chengdu 610065 ChinaProfessor

Shaking table tests of a 1:10 scale arch model performed to investigate the seismic behavior and resistance of concrete filled steel tubular (CFT) arch structures are described in this paper. The El-Centro record and Shanghai artificial wave were adopted as the input excitation. The entire test process can be divided into three stages depending on the lateral brace configurations, i.e., fully (five) braced, two braces removed, and all braces removed. A total of 46 tests, starting from the elastic state to failure condition, have been conducted. The natural vibration frequencies, responses of acceleration, displacement and strain were measured. From the test results, it is demonstrated that the CFT arch structures are capable of resisting severe ground motions and that CFT arches offer a credible alternative to reinforced concrete arches, especially in regions of high seismic intensity.

关键词： concrete filled steel tube arch structures shaking table test seismic behavior lateral braces

Visual fatigue relief zone in an extra-long tunnel using virtual reality with wearable EEG-based devices

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Journal of Central South University 2021年第12期28卷 3871-3881页

作者： LI Xiao-jun LING Jia-xin SHEN Yi Department of Geotechnical eng.neering Tongji UniversityShanghai 200092China key laboratory of Geotechnical and Underground eng.neering of the Ministry of Education Tongji UniversityShanghai 200092China

Long-time driving and monotonous visual environment increase the safety risk of driving in an extra-long tunnel. Driving fatigue can be effectively relieved by setting the visual fatigue relief zone in the tunnel. However, the setting form of visual fatigue relief zone, such as its leng.h and location, is difficult to be designed and quantified. By integrating virtual reality(VR) apparatus with wearable electroencephalogram(EEG)-based devices, a hybrid method was proposed in this study to assist analyzers to formulate the layout of visual fatigue relief zone in the extra-long *** virtual environment of this study was based on an 11.5 km extra-long tunnel located in Yunnan Province in *** results indicated that the use of natural landscape decoration inside the tunnel could improve driving fatigue with the growth rate of attention of the driver increased by more than 20%. The accumulation of driving fatigue had a negative effect on the fatigue relief. The results demonstrated that the optimal location of the fatigue relief zone was at the place where driving fatigue had just occurred rather than at the place where a certain amount of driving fatigue had accumulated.

关键词： virtual reality visual environment driving fatigue extra-long tunnel EEG-based device

Shear-critical reinforced concrete columns under various loading rates

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Frontiers of Structural and civil eng.neering 2014年第4期8卷 362-372页

作者： Witarto WITARTO Liang LU Rachel Howser ROBERTS Y. L. MO Xilin LU Department of civil and Environmental eng.neering University of Houston Houston TX 77004 USA College of civil eng.neering Tongji University Shanghai 200092 China Energo eng.neering A KBR Company Houston TX 77002 USA

This paper presents an experimental study of shear-governed reinforced concrete columns subjected to different loading rates. Four typical short columns were tested cyclically with loading rate of 0.05, 1, 3, and 5 Hz, simulating seismic load. Test result indicated that the loading rate does not affect the column behavior when the rate is up to 5 Hz. Furthermore, Carbon Nano-Fiber Aggregates （CNFAs） were utilized as internal sensors to detect the damage in the column. The test result shows that the CNFAs work well sensing the structural behavior. The CNFA output was further quantitatively correlated to the structural damage level. Finally, a finite element analytical model was constructed to describe the behavior of short columns with shear failure. The analytical model successfully modeled the cyclic loading test results.

关键词： reinforced concrete columns shear failure loading rate Carbon Nano-Fiber Aggregates (CNFAs) finite element analysis OpenSees

用于火电厂减震的变质量MTMD基于可靠度的优化（英文）

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工程科学与技术 2018年第3期50卷 82-90页

作者：戴靠山李伯维李卉颖王健泽李昂刘恺 TESFAMARIAM Solomon 四川大学土木工程系四川成都610065 同济大学土木工程防灾国家重点实验室上海200092 School of eng. Univ. of British Columbia British Columbia

提出了一种针对变质量的非传统多调谐阻尼器(MTMD)基于可靠度的优化设计方法。其中主结构部分考虑多阶模态,MTMD则考虑为集中质量。地震动激励采用金井清模型,利用状态空间法提高计算效率。地震危险性则依据地震动衰减关系和Gutenberg-R... 详细信息

提出了一种针对变质量的非传统多调谐阻尼器(MTMD)基于可靠度的优化设计方法。其中主结构部分考虑多阶模态,MTMD则考虑为集中质量。地震动激励采用金井清模型,利用状态空间法提高计算效率。地震危险性则依据地震动衰减关系和Gutenberg-Richter模型模拟。定义危险性、主结构与多调谐阻尼器相关参数均为随机变量,通过考虑结构多维输出及对应限值,并结合激励与结构随机性得到结构绝对失效概率,并进一步以绝对失效概率为目标函数形成优化问题,通过求解变质量MTMD最优解进行设计。本文将该方法应用于带多煤斗的火电厂房煤斗隔震设计。其中,煤斗隔震形成MTMD,而煤斗内部储煤量变化则形成变质量MTMD。采用拉丁超立方抽样法生成样本,研究确定了合适样本数。通过选取结构角柱位移角作为结构响应,采用规范限值计算失效概率。利用基因算法求解了该优化问题并得到了最优设计与对应的失效概率。本文进一步对比了平动隔震体系和摆隔震体系。研究表明,尽管摆体系的频率与质量不相关,其失效概率并未优于平动隔震体系;且摆体系摆动圆弧曲率的变异系数对结构失效概率影响不大,规律不明显。最后,将煤斗与主结构碰撞亦考虑为失效事件,考虑了煤斗碰撞问题。本文所提出的设计方法基于可靠度,直接以降低结构失效概率为目标,可同时考虑结构多维输出以及煤斗与主结构相对位移,并对应地考虑多个响应限值,将多个响应综合为一个失效概率,避免了计算量巨大的多目标优化。

关键词：非传统调谐阻尼器质量不确定火电厂减震可靠度优化设计

Mapping Network-Coordinated Stacked Gated Recurrent Units for Turbulence Prediction

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IEEE/CAA Journal of Automatica Sinica 2024年第6期11卷 1331-1341页

作者： Zhiming Zhang Shangce Gao Meng.hu Zhou Meng.ao Yan Shuyang Cao Faculty of eng.neering University of ToyamaToyama 930-8555Japan Helen and John C.Hartmann Department of Electrical and Computer eng.neering New Jersey Institute of TechnologyNewark NJ 07102 USA Gaoling School of Artificial Intelligence Renmin University of ChinaBeijing 100872China College of civil eng.neering Tongji UniversityShanghai 200092China IEEE

Accurately predicting fluid forces acting on the sur-face of a structure is crucial in eng.neering ***,this task becomes particularly challeng.ng in turbulent flow,due to the complex and irregular changes in the flow *** this study,we propose a novel deep learning method,named mapping net-work-coordinated stacked gated recurrent units(MSU),for pre-dicting pressure on a circular cylinder from velocity ***-cally,our coordinated learning strategy is designed to extract the most critical velocity point for prediction,a process that has not been explored *** our experiments,MSU extracts one point from a velocity field containing 121 points and utilizes this point to accurately predict 100 pressure points on the *** method significantly reduces the workload of data measure-ment in practical eng.neering *** experimental results demonstrate that MSU predictions are highly similar to the real turbulent data in both spatio-temporal and individual ***,the comparison results show that MSU predicts more precise results,even outperforming models that use all velocity field *** with state-of-the-art methods,MSU has an average improvement of more than 45%in various indicators such as root mean square error(RMSE).Through comprehensive and authoritative physical verification,we estab-lished that MSU’s prediction results closely align with pressure field data obtained in real turbulence *** confirmation underscores the considerable potential of MSU for practical applications in real eng.neering *** code is available at https://***/zhangzm0128/MSU.

关键词： Convolutional neural network deep learning recurrent neural network turbulence prediction wind load predic-tion.

Simulation of thermal expansion mismatch at high temperature

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Underground Space 2023年第1期8卷 210-228页

作者： Zhifei Gao Linbing Wang Hongtao Zhang National Center for Materials Service Safety University of Science and Technology BeijingBeijing 100083China Joint USTB-Virginia Tech Lab on Multifunctional Materials University of Science and Technology BeijingBeijing 100083China Joint USTB-Virginia Tech Lab on Multifunctional Materials Virginia TechBlacksburgVA 24061USA Department of civil eng.neering North China University of TechnologyBeijing 100144China

The thermal expansion mismatch between cement mortar and aggregate at high temperature is one of the main reasons causing the deterioration of concrete at high *** this study,the thermal damage of concrete caused by the thermal expansion mismatch between aggregate and cement mortar was investigated using a meso-scale concrete *** meso-scale concrete model is composed of mortar,aggregate and the interfacial transition zone(ITZ).laboratory tests on the mechanical properties of cement mortar at high temperature were conducted to provide the necessary mechanical parameter for the meso-scale concrete *** simulation results show that the particle size,content,distribution and mechanical properties of the aggregate have an effect on the thermal damage of concrete at high *** smaller the particle size of concrete aggregate and the higher the elastic modulus of aggregate,the greater the damage of concrete under high *** to the increasing thermal expansion difference between aggregate and cement mortar,and the deterioration of the cement mortar with the increasing temperature,the damage of concrete increased sharply after 500℃.

关键词： Cement mortar Concrete High temperature Thermal expansion mismatch Meso-scale model

基于路网连通可靠度的边坡韧性提升决策优化方法

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中国科学：技术科学 2024年第12期54卷 2392-2404页

作者：何正迎黄雨 AKIYAMA Mitsuyoshi 李垠柯郭桢 FRANGOPOL Dan M. 同济大学土木工程学院地下建筑与工程系上海200092 同济大学土木工程防灾减灾全国重点实验室上海200092 Department of civil and Environmental eng.neering School of Creative Science and EngineeringWaseda UniversityTokyo 1698555Japan Department of civil and Environmental eng.neering Engineering Research Center for Advanced Technology for Large Structural Systems(ATLSS Center)Lehigh UniversityBethlehem 18015USA

降雨诱发的群发性滑坡,往往导致多处路段交通中断和路网连通性受损,降低城市道路基础设施网络韧性.鉴于现阶段针对单体边坡的优化设计方法难以最大程度减轻其对路网的广泛影响并提升区域韧性,本文提出了一种基于路网连通可靠度的边坡韧... 详细信息

降雨诱发的群发性滑坡,往往导致多处路段交通中断和路网连通性受损,降低城市道路基础设施网络韧性.鉴于现阶段针对单体边坡的优化设计方法难以最大程度减轻其对路网的广泛影响并提升区域韧性,本文提出了一种基于路网连通可靠度的边坡韧性提升优化决策分析方法.首先,采用广义帕累托分布(generalized Pareto distribution,GPD)评估降雨灾害强度.接着,通过地质调查确定路网中脆弱边坡群位置,并基于边坡渗流-稳定性力学模型进行易损性评估.然后,考虑强降雨下边坡状态的空间相关性,并结合图论,通过蒙特卡罗方法计算路网连通可靠度.最后,基于边坡韧性提升后的路网连通可靠度对道路边坡进行重要度排序,在资源有限条件下,优先加固对路网连通可靠性影响大的脆弱边坡,以最大化区域路网连通性.将所提方法应用于浙江省丽水市易受降雨滑坡群影响的路网,验证了其有效性.结果表明:所提方法得到的最优边坡韧性提升策略显著提升了路网连通可靠度,为将基于可靠度的单体边坡设计转向关注区域功能性的边坡群韧性提升策略的研究范式奠定了基础.

关键词：降雨滑坡群边坡加固路网连通性蒙特卡罗模拟抗灾韧性

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