检索结果-南通市图书馆

A discretely damped SDOF model for the rocking response of freestanding blocks

在线全文

学校读者我要写书评

暂无评论

Earthquake Engineering and Engineering Vibration 2022年第3期21卷 729-740页

作者： Liu Hanquan Huang Yuli qu zhe Key Laboratory of Earthquake Engineering and Engineering Vibration Institute of Engineering MechanicsChina Earthquake AdministrationKey Laboratory of Earthquake Disaster MitigationMinistry of Emergency ManagementHarbin 150080China Sanhe 065201China Arup San FranciscoCA 94105USA

This paper presents a single-degree-of-freedom(SDOF)constitutive model for assessing the performance of freestanding block contents of *** model incorporates a bespoke damper to account for energy dissipation associated with *** is advantageous in its direct correlation,via energy conservation,to the restitution coefficient for impact during rocking.A comparative study with the existing SDOF rocking models shows that the proposed model significantly improves the accuracy of free-rocking simulations,in which inherent damping predominantly affects *** provides a promising and efficient tool for computationally intensive performance evaluation of nonstructural components.

关键词： contents rigid block equivalent viscous damping free rocking forced rocking single-degree-of-freedom system

Role of dampers on the seismic performance of pin-supported wall-frame structures

在线全文

学校读者我要写书评

暂无评论

Earthquake Engineering and Engineering Vibration 2023年第2期22卷 453-467页

作者： Wang Xiaoyue qu zhe Gong Ting Key Laboratory of Earthquake Engineering and Engineering Vibration Institute of Engineering MechanicsChina Earthquake AdministrationSanhe 065201China Key Laboratory of Earthquake Disaster Mitigation Ministry of Emergency ManagementHarbin 150080China China Re Catastrophe Risk Management Company Ltd. Beijing 100000China

Pin-supported(PS)walls have been proven effective in avoiding weak story failure of frame structures by increasing the height-wise continuous stiffness and producing uniform distribution of story ***,little attention has been given to the floor velocity or acceleration responses of PS wall-frame structures,which predominate the seismic damage of various nonstructural components that are critical to the immediate occupancy and quick recovery of *** paper presents a numerical evaluation of the floor velocity and acceleration responses of PS wall-frame structures,highlighting the effects of different types of dampers accompanying the PS *** results show that the PS walls alone significantly increase the peak floor velocity(PFV)and peak floor acceleration(PFA)*** wall-frame structures with either steel or viscoelastic(VE)dampers are much less effective in reducing the PFV or PFA responses than they are in reducing the peak inter-story drift ratio(PIDR).The impact of this behavior is demonstrated by a seismic fragility analysis that incorporates demand parameters combining the maximum PIDR,average PFV and *** results show that the use of VE dampers rather than hysteretic dampers results in better protection of nonstructural components in PS wall-frame structures.

关键词： strong spine system energy-dissipating device floor acceleration floor velocity nonstructural damage

Lessons from the seismic behavior of a steel grid roof structure heavily damaged in Lushan earthquake

在线全文

学校读者我要写书评

暂无评论

Earthquake Engineering and Engineering Vibration 2019年第1期18卷 95-111页

作者： Li Jichao qu zhe Wang Tao Key Laboratory of Earthquake Engineering and Engineering Vibration Institute of Engineering MechanicsChina Earthquake Administration

The seismic behavior of a school gymnasium, whose steel grid roof was heavily damaged during the Mw6.6 Lushan earthquake in 2013, is simulated through nonlinear dynamic analysis. The simulated damage is compared with field observations to validate the numerical model, based on which a parametric study was performed to provide insight into the failure process and damage patterns of steel grids. The results suggest that the grid damage is strongly related to roofsubstructure interactions. These include not only the substructure's amplification of the vibration, but the uncoordinated displacement of the substructure's columns which support the grid also play an equally important role. In particular, the latter effect may significantly alter the internal force distribution in the steel grid and lead to unexpected buckling of members that are proportioned as tension-only members. While such interactions are generally not accounted for in the design practice for grid structures in China, similar seismic damage may be expected for other existing grid roofs in future earthquakes. As is also demonstrated in this study, seismic isolation of the roof is a promising solution to protect grid roof structures by mitigating the detrimental effects of roof-substructure interactions.

关键词： Lushan earthquake steel space structure roof-substructure interaction nonlinear dynamic analysis seismic isolation vertical ground motion

Shake table tests of suspended ceilings to simulate the observed damage in the M_s 7.0 Lushan earthquake, China

在线全文

学校读者我要写书评

暂无评论

Earthquake Engineering and Engineering Vibration 2016年第2期15卷 239-249页

作者： Wang Duozhi Dai Junwu qu zhe Ning Xiaoqing Key Laboratory of Earthquake Engineering and Engineering Vibration Institute of Engineering MechanicsChina Earthquake Administration

Severe damage to suspended ceilings of metal grids and lay-in panels was observed in public buildings during the 2013 M7.0 Lushan earthquake in China. Over the past several years, suspended ceilings have been widely used practice in public buildings throughout China, including government offices, schools and hospitals. To investigate the damage mechanism of suspended ceilings, a series of three-dimensional shake table tests was conducted to reproduce the observed damage. A full-scale reinforced concrete frame was constructed as the testing frame for the ceiling, which was single-story and infilled with brick masonry walls to represent the local construction of low-rise buildings. In general, the ceiling in the tests exhibited similar damage phenomena as the field observations, such as higher vulnerability of perimeter elements and extensive damage to the cross runners. However, it exhibited lower fragility in terms of peak ground/roof accelerations at the initiation of damage. Further investigations are needed to clarify the reasons for this behavior.

关键词： suspended ceiling Lushan earthquake Wenchuan earthquake shake table test wall closure acoustic mineral fiber panel

Evaluation of the fishbone model in simulating the seismic response of multistory reinforced concrete moment-resisting frames

在线全文

学校读者我要写书评

暂无评论

Earthquake Engineering and Engineering Vibration 2019年第2期18卷 315-330页

作者： qu zhe Gong Ting Li Qiqi Wang Tao Key Laboratory of Earthquake Engineering and Engineering Vibration Institute of Engineering MechanicsChina Earthquake Administration China Architecture Design & Research Group

The fishbone model is a simplified numerical model for moment-resisting frames that is capable of modelling the effects of column-beam strength and stiffness ratios. The applicability of the fishbone model in simulating the seismic responses of reinforced concrete moment-resisting frames of different sets of column-beam strength and stiffness ratios are evaluated through nonlinear static, dynamic and incremental dynamic analysis on six prototype buildings of 4-, 8-and 12-stories. The results show that the fishbone model is practically accurate enough for reinforced concrete frames, although the assumption of equal joint rotation does not hold in all cases. In addition to the ground motion characteristics and the number of stories in the structures, the accuracy of the model also varies with the column-beam stiffness and strength ratios. The model performs better for strong column-weak beam frames, in which the lateral drift patterns are better controlled by the continuous stiffness provided by the strong columns. When the inelastic deformation is large, the accuracy of the model may be subjected to large record-to-record variability. This is especially the case for frames of weak columns.

关键词： fishbone model reinforced concrete frame strong column-weak beam column-beam stiffness ratio incremental dynamic analysis

A complete introduction to the SCJ proposal and its commentary on the development of seismically resilient cities

在线全文

学校读者我要写书评

暂无评论

Earthquake Engineering and Engineering Vibration 2018年第4期17卷 677-691页

作者： Akira Wada Ikuo Towhata Kazuo Tamura qu zhe Tokyo Institute of Technology Tokyo 152-8550 Japan University of Tokyo Tokyo 153-8914 Japan Faculty of Engineering Chiba Institute of Technology Chiba 275-0016 Japan Institute of Engineering Mechanics China Earthquake Administration Harbin 150080 China

In modern society, the population, wealth and social functions are increasingly concentrated in a few large cities. Such concentration brings about efficiency while at the same time it increases the vulnerability of the society. To address this issue, the Science Council of Japan（SCJ） published a proposal entitled ＂Shape Cities and Societies Safer against Severe Earthquakes＂. It makes a variety of suggestions for enhancing the seismic resilience of large cities, including：（1） comprehensive thinking based on the latest scientific knowledge and rich imagination;（2） selection of sites suitable for residence and social activities;（3） introducing the urban seismic coefficient;（4） promoting the enhancement of the seismic performance of buildings and civil structures;（5） easing the concentration of population and functions;（6） building communities that enable shelter and escape;（7） resilient technology of information and communication system and its effective utilization;（8） preparation and implementation of emergency response after earthquakes;（9） development and application of new structural seismic technology;（10） learning from domestic and foreign earthquake disasters and launching of international cooperation and knowledge sharing and（11） taking actions from a multidisciplinary perspective. The proposal is introduced in this paper.

关键词： large earthquake large city urban disaster resilience society earthquake engineering

Uncertainty in the seismic performance of semi-active base isolation systems

在线全文

学校读者我要写书评

暂无评论

Earthquake Research Advances 2023年第2期3卷 62-70页

作者： Xiaoyue Wang zhe qu Key Laboratory of Earthquake Disaster Mitigation Ministry of Emergency Management.Key Laboratory of Earthquake Engineering and Engineering VibrationInstitute of Engineering MechanicsChina Earthquake AdministrationHebei065201China

In a conventional base isolation system,minimizing the seismic responses of the superstructure is always at the cost of increasing the isolator's *** semi-active control of the isolator has been considered an effective solution to such a *** tunes the real-time properties of the isolator according to preset rules to further reduce the superstructure's seismic responses without increasing that of the isolator or vice ***,the number of ground motion records used to design and validate the controller,i.e.,the preset rules,in existing studies is usually very small and therefore is suspectable if it is adequate to address the significant uncertainty in the shaking of future *** paper critically reviews the performance of the proportional-integralderivative(PID),linear-quadratic regulator(LQR),and fuzzy controllers in semi-active base isolation systems with magnetorheological(MR)dampers subjected to highly uncertain ground motion inputs through numerical *** results show that the control performance of the controllers varies significantly with the increasing number of input records,suggesting the necessity of using at least 50 ground motion records to appropriately assess the performance uncertainty of semi-active base isolation *** importantly,the superior performance of the optimized controllers is not guaranteed if the system is subjected to ground motions that are new to the controller,even if the controller has been optimized for thousands of existing ground *** highlights the need of improving the adaptability of the semi-active systems for uncertain ground motion inputs.

关键词： Seismic isolation Semi-active control MR damper Control performance Uncertainty

Preliminary investigation of seismic damage to two steel space structures during the 2013 Lushan earthquake

在线全文

学校读者我要写书评

暂无评论

Earthquake Engineering and Engineering Vibration 2013年第3期12卷 497-500页

作者： Dai Junwu qu zhe Zhang Chenxiao Weng Xuran Key Laboratory of Earthquake Engineering and Engineering Vibration Institute of Engineering MechanicsCEA

Severe damage to steel space structures is rarely reported when compared to other structural systems damaged during past major earthquakes around the world. Two gymnasiums of steel space structures in downtown Lushan County that were damaged during the 2013 M7.0 Lushan earthquake in China were investigated and the observations are summarized in this paper. Typical damage to these two steel space structures ranges from moderate to severe. Moderate damage includes global buckling and dislocation of bolted connections of truss members, and inelastic elongation of anchor bolts and sliding of pedestal plates of supports. Severe damage includes member fracture caused by local buckling, and fracture failure of anchor bolts and welds. The distribution of structural damage to these two structures is described in detail and future research opportunities are suggested.

关键词： Lushan earthquake steel space structure gymnasitun seismic damage member buckling fracture failure

Asymmetry between the upper and lower visual fields An event-related potential study

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2006年第5期51卷 536-541页

作者： qu zhe SONG Yan DING Yulong Key Laboratory of Cognitive Science Graduate School Institute of Biophysics Chinese Academy of Sciences Beijing 100039 China Department of Psychology Sun Yat-Sen University Guangzhou510275 China State Key Laboratory of Cognitive Neuroscience and Learning Beijing Normal University Beijing 100875 China

Using event-related potentials (ERPs), the present study examined the electrophysiological and attentional asymmetries between the upper vis- ual field (UVF) and the lower visual field (LVF) while subjects were performing a target detecting task. The early ERP components showed a smaller P1 and a larger N1 in LVF than in UVF over the oc- cipito-parietal areas, while the late components (N2 and P3) showed no difference between the two visual fields. In addition, the attention enhancement on the P1 component was greater in UVF than in LVF. These findings suggest that the function of the UVF and LVF differ in terms of both early visual informa- tion processing and attentional modulation.

关键词：事件相关性电位电生理学视觉信息处理不对称性上视野下视野