资源类型

期刊论文 220

会议视频 9

年份

2023 13

2022 18

2021 12

2020 10

2019 10

2018 20

2017 11

2016 7

2015 8

2014 7

2013 5

2012 7

2011 10

2010 11

2009 28

2008 2

2007 14

2006 7

2005 7

2004 2

展开 ︾

关键词

地震 9

汶川地震 8

地震预测 6

故障诊断 6

临震信号 3

卫星 3

三峡工程 2

台湾海峡 2

地球物理 2

地质灾害 2

地震危险性 2

地震灾害 2

地震预报 2

大坝 2

强震发生断层 2

故障 2

深部裂缝带 2

能源 2

诊断 2

展开 ︾

检索范围:

排序: 展示方式:

Probabilistic seismic response and uncertainty analysis of continuous bridges under near-fault ground

Hai-Bin MA, Wei-Dong ZHUO, Davide LAVORATO, Camillo NUTI, Gabriele FIORENTINO, Giuseppe Carlo MARANO, Rita GRECO, Bruno BRISEGHELLA

《结构与土木工程前沿(英文)》 2019年 第13卷 第6期   页码 1510-1519 doi: 10.1007/s11709-019-0577-8

摘要: Performance-based seismic design can generate predictable structure damage result with given seismic hazard. However, there are multiple sources of uncertainties in the seismic design process that can affect desired performance predictability. This paper mainly focuses on the effects of near-fault pulse-like ground motions and the uncertainties in bridge modeling on the seismic demands of regular continuous highway bridges. By modeling a regular continuous bridge with OpenSees software, a series of nonlinear dynamic time-history analysis of the bridge at three different site conditions under near-fault pulse-like ground motions are carried out. The relationships between different Intensity Measure (IM) parameters and the Engineering Demand Parameter (EDP) are discussed. After selecting the peak ground acceleration as the most correlated IM parameter and the drift ratio of the bridge column as the EDP parameter, a probabilistic seismic demand model is developed for near-fault earthquake ground motions for 3 different site conditions. On this basis, the uncertainty analysis is conducted with the key sources of uncertainty during the finite element modeling. All the results are quantified by the “swing” base on the specific distribution range of each uncertainty parameter both in near-fault and far-fault cases. All the ground motions are selected from PEER database, while the bridge case study is a typical regular highway bridge designed in accordance with the Chinese Guidelines for Seismic Design of Highway Bridges. The results show that PGA is a proper IM parameter for setting up a linear probabilistic seismic demand model; damping ratio, pier diameter and concrete strength are the main uncertainty parameters during bridge modeling, which should be considered both in near-fault and far-fault ground motion cases.

关键词: continuous bridge     probabilistic seismic demand model     Intensity Measure     near-fault     uncertainty    

Seismic responses and resilience of novel SMA-based self-centring eccentrically braced frames under near-fault

Zhi-Peng CHEN; Songye ZHU

《结构与土木工程前沿(英文)》 2022年 第16卷 第8期   页码 962-975 doi: 10.1007/s11709-022-0873-6

摘要: In this paper, the seismic responses and resilience of a novel K-type superelastic shape memory alloy (SMA) self-centring (SC) eccentrically braced frame (EBF) are investigated. The simulation models of the SMA-based SC-EBF and a corresponding equal-stiffness traditional EBF counterpart are first established based on some existing tests. Then twenty-four near-fault ground motions are used to examine the seismic responses of both EBFs under design basis earthquake (DBE) and maximum considered earthquake (MCE) levels. Structural fragility and loss analyses are subsequently conducted through incremental dynamic analyses (IDA), and the resilience of the two EBFs are eventually estimated. The resilience assessment basically follows the framework proposed by Federal Emergency and Management Agency (FEMA) with the additional consideration of the maximum residual inter-storey drift ratio (MRIDR). The novel SMA-based SC-EBF shows a much better resilience in the study and represents a promising attractive alternative for future applications.

关键词: shape memory alloy     eccentrically braced frame     self-centring     fragility     loss function     resilience    

Parametric study on the Multangular-Pyramid Concave Friction System (MPCFS) for seismic isolation

Wei XIONG, Shan-Jun ZHANG, Li-Zhong JIANG, Yao-Zhuang LI

《结构与土木工程前沿(英文)》 2020年 第14卷 第5期   页码 1152-1165 doi: 10.1007/s11709-020-0659-7

摘要: A series of comprehensive parametric studies are conducted on a steel-frame structure Finite-Element (FE) model with the Multangular-Pyramid Concave Friction System (MPCFS) installed as isolators. This new introduced MPCFS system has some distinctive features when compared with conventional isolation techniques, such as increased uplift stability, improved self-centering capacity, non-resonance when subjected to near-fault earthquakes, and so on. The FE model of the MPCFS is first established and evaluated by comparison between numerical and theoretical results. The MPCFS FE model is then incorporated in a steel-frame structural model, which is subjected to three chosen earthquakes, to verify its seismic isolation. Further, parametric study with varying controlling parameters, such as isolation foundation, inclination angle, friction coefficient, and earthquake input, is carried out to extract more detailed dynamic response of the MPCFS structure. Finally, limitations of this study are discussed, and conclusions are made. The simulations testify the significant seismic isolation of the MPCFS. This indicates the MPCFS, viewed as the beneficial complementary of the existing well-established and matured isolation techniques, may be a promising tool for seismic isolation of near-fault earthquake prone zones. This verified MPCFS FE model can be incorporated in future FE analysis. The results in this research can also guide future optimal parameter design of the MPCFS.

关键词: seismic isolation     variable frequency     near-fault earthquake     numerical study     Multangular-Pyramid Concave Friction System    

Computational studies on the seismic response of the State Route 99 bridge in Seattle with SMA/ECC plastic hinges

Jiping GE, M. Saiid SAIIDI, Sebastian VARELA

《结构与土木工程前沿(英文)》 2019年 第13卷 第1期   页码 149-164 doi: 10.1007/s11709-018-0482-6

摘要: This paper reports a computational study on the seismic response of a three-span highway bridge system incorporating conventional and novel substructure details for improved seismic performance. The bridge has three continuous spans supported by two single-column piers and integral abutments founded on drilled shafts. It will be the first full-scale highway bridge to use superelastic shape memory alloy bars (SMA) and engineered cementitious composite (ECC) to mitigate column plastic hinge damage and minimize residual displacements after a strong earthquake. A three-dimensional computational model capturing the nonlinear constitutive response of the novel materials and the effects of dynamic soil-structure interaction was developed to assess the seismic response of the bridge in finite-element software OpenSees. Two versions of the same bridge were analyzed and compared, one with conventional cast-in-place reinforced concrete columns, and the other with top plastic hinges incorporating Nickel-Titanium (NiTi) SMA reinforcing bars and ECC. The novel SMA/ECC plastic hinges were found to substantially reduce damage and post-earthquake residual displacements in the bridge substructure, but led to larger maximum drifts relative to the bridge with conventional reinforced concrete plastic hinges. The analysis results suggested that the novel plastic hinges could lead to improved post-earthquake serviceability of bridges after intense earthquakes.

关键词: seismic design     analytical simulation     near-fault earthquakes     shape memory alloy     engineered cementitious composite     self-centering    

强震成功预报的曙光

李玶,杨美娥

《中国工程科学》 2009年 第11卷 第6期   页码 19-27

摘要: 20世纪50年代以来,我国30多次成功预报了中、强地震的发生;近20年来国外有些地震学家对几次强震预测失败感到失望,逐渐将地震研究的主攻方向转变为对建筑物抗震能力的鉴定、加强建筑物抗震措施和建立现代数字台网,以便迅速准确确定强震的发生地点,可以即刻到现场救援;国内地震界部分地震学家受他们的悲观情绪的影响,也放弃了对强震预报的努力。所幸的是部分专业和业余地震学家仍在强震预报领域做出了不懈的努力,取得了可喜的成绩。

关键词: 汶川地震     强震预报     强震发生断层    

国际对比研究计划——面向地震预测的跨断层测量

何满潮, 隋麒儒, 陶志刚​​​​​​​

《工程(英文)》 2023年 第31卷 第12期   页码 15-18 doi: 10.1016/j.eng.2023.03.016

Study on the Path of “Near-zero Emission” Coal-based Clean Energy Ecosystem Development

Zhang Yu-zhuo

《工程管理前沿(英文)》 2014年 第1卷 第1期   页码 37-41 doi: 10.15302/J-FEM-2014007

摘要: Developing a "near-zero emission" coal-based clean energy ecosystem bears great significance for the sustainable development of clean energy in China and the world at large. This article delves into the development strategy, implementation pathways and key priorities of China's "near-zero emission" coal-based clean energy ecosystem, and in turn proposes specific measures to underpin the development and implementation of such system.

关键词: near-zero emission     clean energy ecosystem     study on the path    

Research and industrialization of near-net rolling technology used in shaft parts

Zhenghuan HU, Baoyu WANG, Zhenhua ZHENG

《机械工程前沿(英文)》 2018年 第13卷 第1期   页码 17-24 doi: 10.1007/s11465-018-0480-3

摘要:

Shaft part rolling is an efficient and green near-net shaping technology offering many advantages, including high production efficiency, high material utilization rate, high product quality, and excellent production environment. In this paper, the features of shaft part rolling are introduced along with the working principles of two main shaft part rolling technologies, namely, cross wedge rolling (CWR) and skew rolling (SR). In relation to this technology, some R&D achievements gained by the University of Science and Technology Beijing are summarized. Finally, the latest developments in shaft part rolling are presented, including SR steel balls, precise forming of camshaft blank by CWR, SR phosphorous copper balls at room temperature, and CWR hollow axle sleeve. Although the shaft part rolling technology has been widely used in China, it only accounts for about 15% of applicable parts at present. Nevertheless, this technology has broad application prospects.

关键词: cross wedge rolling     skew rolling     near-net rolling     shaft part    

Special issue: Near-net shaping technology

Dequn LI, Dongming GUO, Qingxue HUANG, Yanchun LOU

《机械工程前沿(英文)》 2018年 第13卷 第1期   页码 1-2 doi: 10.1007/s11465-018-0497-7

汶川大地震周年与地质灾害防治再思考

卢耀如

《中国工程科学》 2009年 第11卷 第6期   页码 36-43

摘要:

汶川大地震已过去一年时间,地震造成巨大灾害至今不能忘记,应当更好地贯彻科学发展观,深入地去思考分析地震灾害的机理,以期能为今后防灾减灾提供有效的科学依据。

关键词: 汶川地震     川滇地震历史     地质灾害     地震机理    

汶川巨震的预测和思考

耿庆国

《中国工程科学》 2009年 第11卷 第6期   页码 123-128

摘要:

根据多年来对旱震关系、强震活动有序性及强磁暴组合法的地震预测探索,就川、甘、青、陕,特别是四川阿坝州地区的地震活动连续3年的研究做了简要的回顾,披露了在汶川地震前的2005 年12 月8 日向中国地震局提交的“关于加强川甘青交界地区强震短临监测和分析预报应急工作的紧急建议”要点。

关键词: 汶川巨震预测     旱震关系     强震活动有序性     强磁暴组合法    

Determining casting defects in near-net shape casting aluminum parts by computed tomography

Jiehua LI, Bernd OBERDORFER, Daniel HABE, Peter SCHUMACHER

《机械工程前沿(英文)》 2018年 第13卷 第1期   页码 48-52 doi: 10.1007/s11465-018-0493-y

摘要:

Three types of near-net shape casting aluminum parts were investigated by computed tomography to determine casting defects and evaluate quality. The first, second, and third parts were produced by low-pressure die casting (Al-12Si-0.8Cu-0.5Fe-0.9Mg-0.7Ni-0.2Zn alloy), die casting (A356, Al-7Si-0.3Mg), and semi-solid casting (A356, Al-7Si-0.3Mg), respectively. Unlike die casting (second part), low-pressure die casting (first part) significantly reduced the formation of casting defects (i.e., porosity) due to its smooth filling and solidification under pressure. No significant casting defect was observed in the third part, and this absence of defects indicates that semi-solid casting could produce high-quality near-net shape casting aluminum parts. Moreover, casting defects were mostly distributed along the eutectic grain boundaries. This finding reveals that refinement of eutectic grains is necessary to optimize the distribution of casting defects and reduce their size. This investigation demonstrated that computed tomography is an efficient method to determine casting defects in near-net shape casting aluminum parts.

关键词: near-net shape casting     aluminum parts     casting defects     low pressure die casting     die casting     semi-solid casting     computed tomography    

从汶川地震震前现象认识其发震动力应具有的大尺度与深层次性

许绍燮

《中国工程科学》 2009年 第11卷 第6期   页码 16-18

摘要:

认为汶川地震发震动力具有大尺度与深层次性,并就汶川地震的震前地震活动性进行了分析研究;大小环圆的交切,全球尺度条带的交会,深部地震活动的加强这几项地震活动性图像是汶川地震震前现象的重要特征,这些特征图像在1976年的唐山地震前也有所显示;条带交会,环圆交会,带圆交会处质点运动各异,相互闭锁,质点运动不易解耦,形成应力集中,常常可成为强震发生的场所;深部闭锁活动的特色,在地表观测中易于失察,成为巨大地震更不易预察的一种原因。鉴于巨大地震灾害的严重性,今后在地震预测监测中应加强对大尺度与深层次信息的监测、收集与分析研究。

关键词: 汶川地震     发震动力的大尺度与深层次性     地震预测    

Chemisorption solid materials for hydrogen storage near ambient temperature: a review

Yiheng ZHANG, Shaofei WU, Liwei WANG, Xuefeng ZHANG

《能源前沿(英文)》 2023年 第17卷 第1期   页码 72-101 doi: 10.1007/s11708-022-0835-7

摘要: Solid chemisorption technologies for hydrogen storage, especially high-efficiency hydrogen storage of fuel cells in near ambient temperature zone defined from −20 to 100°C, have a great application potential for realizing the global goal of carbon dioxide emission reduction and vision of carbon neutrality. However, there are several challenges to be solved at near ambient temperature, i.e., unclear hydrogen storage mechanism, low sorption capacity, poor sorption kinetics, and complicated synthetic procedures. In this review, the characteristics and modification methods of chemisorption hydrogen storage materials at near ambient temperature are discussed. The interaction between hydrogen and materials is analyzed, including the microscopic, thermodynamic, and mechanical properties. Based on the classification of hydrogen storage metals, the operation temperature zone and temperature shifting methods are discussed. A series of modification and reprocessing methods are summarized, including preparation, synthesis, simulation, and experimental analysis. Finally, perspectives on advanced solid chemisorption materials promising for efficient and scalable hydrogen storage systems are provided.

关键词: hydrogen storage capacity     chemisorption     near-ambient-temperature     modification methods     alloy hydrides    

Factors influencing near infrared spectroscopy analysis of agro-products: a review

Xiao XU, Lijuan XIE, Yibin YING

《农业科学与工程前沿(英文)》 2019年 第6卷 第2期   页码 105-115 doi: 10.15302/J-FASE-2019255

摘要:

The near infrared (NIR) spectroscopy technique has wide applications in agriculture with the advantages of being nondestructive, sensitive, safe and rapid. However, there are still more than 40 error sources influencing the robustness and accuracy of its calibration and operation. Environmental, sample and instrument factors that influence the analysis are discussed in this review, including temperature, humidity and other factors that introduce uncertainty. Error sources from livestock products, fruit and vegetables, which are the most common objects in the field of NIR analysis, are also emphasized in the second part. In addition, studies utilizing different instruments, spectral pretreatments, variable selection methods, wavelength ranges, detection modes and calibration methods are tabulated to illustrate the complications they introduce and how they influence NIR analysis. It is suggested that large scale of data with abundant varieties can be used to build a more robust calibration model, in order to improve the robustness and accuracy of the NIR analytical model, and overcome problems caused by confining analysis to too many uniform samples.

关键词: agro-product     error source     influence factor     near infrared spectroscopy    

标题 作者 时间 类型 操作

Probabilistic seismic response and uncertainty analysis of continuous bridges under near-fault ground

Hai-Bin MA, Wei-Dong ZHUO, Davide LAVORATO, Camillo NUTI, Gabriele FIORENTINO, Giuseppe Carlo MARANO, Rita GRECO, Bruno BRISEGHELLA

期刊论文

Seismic responses and resilience of novel SMA-based self-centring eccentrically braced frames under near-fault

Zhi-Peng CHEN; Songye ZHU

期刊论文

Parametric study on the Multangular-Pyramid Concave Friction System (MPCFS) for seismic isolation

Wei XIONG, Shan-Jun ZHANG, Li-Zhong JIANG, Yao-Zhuang LI

期刊论文

Computational studies on the seismic response of the State Route 99 bridge in Seattle with SMA/ECC plastic hinges

Jiping GE, M. Saiid SAIIDI, Sebastian VARELA

期刊论文

强震成功预报的曙光

李玶,杨美娥

期刊论文

国际对比研究计划——面向地震预测的跨断层测量

何满潮, 隋麒儒, 陶志刚​​​​​​​

期刊论文

Study on the Path of “Near-zero Emission” Coal-based Clean Energy Ecosystem Development

Zhang Yu-zhuo

期刊论文

Research and industrialization of near-net rolling technology used in shaft parts

Zhenghuan HU, Baoyu WANG, Zhenhua ZHENG

期刊论文

Special issue: Near-net shaping technology

Dequn LI, Dongming GUO, Qingxue HUANG, Yanchun LOU

期刊论文

汶川大地震周年与地质灾害防治再思考

卢耀如

期刊论文

汶川巨震的预测和思考

耿庆国

期刊论文

Determining casting defects in near-net shape casting aluminum parts by computed tomography

Jiehua LI, Bernd OBERDORFER, Daniel HABE, Peter SCHUMACHER

期刊论文

从汶川地震震前现象认识其发震动力应具有的大尺度与深层次性

许绍燮

期刊论文

Chemisorption solid materials for hydrogen storage near ambient temperature: a review

Yiheng ZHANG, Shaofei WU, Liwei WANG, Xuefeng ZHANG

期刊论文

Factors influencing near infrared spectroscopy analysis of agro-products: a review

Xiao XU, Lijuan XIE, Yibin YING

期刊论文