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An alternative construction of normalized seismic design spectra for near-fault regions

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Earthquake Engineering and Engineering Vibration 2013年第3期12卷 351-362页

作者： Ni Shunhao Li Shuang Chang Zhiwang xie lili School of Civil Engineering Harbin Institute of Technology Department of Civil and Environmental Engineering University of Waterloo Institute of Engineering Mechanics China Earthquake Administration

This paper presents a methodology for constructing seismic design spectra in near-fault regions. By analyzing the characteristics of near-fault pulse-type ground motions, an equivalent pulse model is proposed, which can well represent the characteristics of the near-fault forward-directivity and fling-step pulse-type ground motions. The normalized horizontal seismic design spectra for near-fault regions are presented using recorded near-fault pulse-type ground motions and equivalent pulse-type ground motions, which are derived based on the equivalent pulse model coupled with ground motion parameter attenuation relations. The normalized vertical seismic design spectra for near-fault regions are obtained by scaling the corresponding horizontal spectra with the vertical-to-horizontal acceleration spectral ratios of near-fault pulse-type ground motions. The proposed seismic design spectra appear to have relatively small dispersion in a statistical sense. The seismic design spectra for both horizontal and vertical directions can provide alternative spectral shapes for seismic design codes.

关键词： near-fault pulse-type ground motion equivalent pulse model attenuation relation seismic design spectra

Green's function of multi-layered poroelastic half-space for models of ground vibration due to railway traffic

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Earthquake Engineering and Engineering Vibration 2017年第2期16卷 311-328页

作者： Wang Futong Tao Xiaxin xie lili Siddharthan Raj Institute of Engineering Mechanics China Earthquake Administration Key Laboratory of Earthquake Engineeringand Engineering Vibration of China Earthquake Administration Harbin 150080 China School of Civil Engineering and Architecture Heilongiiang University Harbin 150080 China School of Civil Engineering Harbin Institute of Technology Harbin 150090 China Department of Civil and Environmental Engineering University of Nevada Reno NV89557 USA

This study proposes a Green＇s function, an essential representation of water-saturated ground under moving excitation, to simulate ground borne vibration from trains. First, general solutions to the governing equations of poroelastic medium are derived by means of integral transform. Secondly, the transmission and reflection matrix approach is used to formulate the relationship between displacement and stress of the stratified ground, which results in the matrix of the Green＇s function. Then the Green＇s function is combined into a train-track-ground model, and is verified by typical examples and a field test. Additional simulations show that the computed ground vibration attenuates faster in the immediate vicinity of the track than in the surrounding area. The wavelength of wheel-rail unevenness has a notable effect on computed displacement and pore pressure. The variation of vibration intensity with the depth of ground is significantly influenced by the layering of the strata soil. When the train speed is equal to the velocity of the Rayleigh wave, the Mach cone appears in the simulated wave field. The proposed Green＇s function is an appropriate representation for a layered ground with shallow ground water table, and will be helpful to understand the dynamic responses of the ground to complicated moving excitation.

关键词： wave propagation poroelastic medium layered half-space train Green's function

Photocatalytic degradation of fipronil in water by silver-modified lithium vanadium phosphate spheres under visible light irradiation

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Science China Chemistry 2015年第12期58卷 1912-1917页

作者： Lifeng Yin lili xie Yueping Bao Junfeng Niu State Key Laboratory of Water Environment Simulation

A novel visible light-driven photocatalyst, lithium vanadium phosphate sphere(LVPS), was prepared by a ball-milling method. For enhancing the photocatalytic performance, LVPS was further modified with silver(ALVPS) by a UV-light photo- reduction method. After modification, the crystalline phase of LVPS did not change, however, the UV-Vis diffuse reflectance spectrum of ALVPS was extended to 656 nm, which greatly improved its photoabsorptivity for visible light and enhanced its electron donating capacity. Under the irradiation of sunlight or visible light(>400 nm), ALVPS can rapidly remove fipronil(a persistent organic pollutant, 5 mg L?1) from aqueous solution. More than 99.7% of fipronil was removed by ALVPS after 0.5 h of irradiation, yielding a much higher removal rate than those achieved by nano-Ti O2 and Bi2O3. Photo-generated carrier trapping experiments were conducted to elucidate the photocatalytic degradation mechanism further. Hydrogen peroxide and potassium bromate suppressed the photocatalytic activity of ALVPS, while superoxide dismutase and sodium azide reinforced it, verifying that photo-generated electrons played a key role in the photochemical reaction.

关键词： lithium vanadium phosphate sphere visible light irradiation photocatalysis degradation

Effects of hanging wall and footwall on demand of structural input energy during the 2008 Wenchuan earthquake

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Earthquake Engineering and Engineering Vibration 2013年第1期12卷 1-12页

作者： Lu Shunan Li Shuang Zhai Changhai xie lili School of Civil Engineering Harbin Institute of Technology College of Civil Engineering and Architecture Harbin University of Science and Technology Institute of Engineering Mechanics China Earthquake Administration

Systematic differences in the duration and frequency content of ground motions from the hanging wall and footwall during the 2008 Wenchuan earthquake are investigated,focusing on the influence of these differences on structural input energy based on the elastic and inelastic energy responses of structures.A comparison of the input energy spectra between the hanging wall and the footwall reveal that the structural input energy on the hanging wall is not amplified due to the short duration and low peak ground velocity to acceleration ratio（V/A）.However,the larger demand of structural input energy on the footwall in the range of medium and long periods is observed and the demand increases up to 50% relative to the average level of structural input energy for rupture distances larger than 30 *** importance of considering the footwall effect on structural input energy when comparing ground motions in the range of medium and long periods is recognized.

关键词： Wenchuan earthquake duration frequency content hanging wall effect footwall effect input energy

A new attenuation model of near-fault ground motions with consideration of the hanging wall effect in the Wenchuan earthquake

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Earthquake Engineering and Engineering Vibration 2011年第3期10卷 313-323页

作者： Peng Lei xie lili Hu Jinjun Wang Dong Institute of Engineering Mechanics China Earthquake Administration Harbin 150080 China School of Civil Engineering and Architecture Harbin Institute of Technology Harbin 150090 China

The hanging wall effect is an important factor that impacts the characteristics of strong ground motions in near-fault areas. Based on a residual analysis of ground motion parameters characterizing the hanging wall effect and in recognition of the nature of the effect, many models have been developed. In this study, after a comprehensive analysis of two existing models, a new model is proposed and used to model the hanging wall effect in horizontal peak ground acceleration （PGAH） and spectral acceleration （SAH） at a period of 0.1s in the Wenchuan earthquake. Finally, comparisons between the modeling results of the hanging wall effect in the Wenchuan earthquake and the results predicted by using Abrahamson and Silva＇s NGA model （AS NGA） indicate that the AS NGA model predicts a much higher hanging wall effect than the model developed in this paper. Furthermore, the AS NGA model predicts a large hanging wall effect even at great distances, while the proposed model more accurately captures the trend of the effect.

关键词： hanging wall effect Wenchuan earthquake attenuation relationship NGA model

Dimensional analysis of earthquake-induced pounding between adjacent inelastic MDOF buildings

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Earthquake Engineering and Engineering Vibration 2015年第2期14卷 295-313页

作者： Zhai Changhai Jiang Shan Li Shuang xie lili School of Civil Engineering Harbin Institute of Technology Key Laboratory of Earthquake Engineering and Engineering Vibration Institute of Engineering Mechanics China Earthquake Administration

In this study the seismic pounding response of adjacent multi-degree-of-freedom(MDOF) buildings with bilinear inter-story resistance characteristics is investigated through dimensional analysis. The application of dimensional analysis leads to a condensed presentation of the response, and the remarkable self-similarity property for bilinear MDOF buildings with inelastic collision is uncovered. It is shown that when the response is expressed in the appropriate dimensionless form, response spectra for any intensity of the excitation collapse to a single master curve. The reduced Π set explicitly describes the interaction between the colliding structures. The effect of pounding on the MDOF building’s response is illustrated using three well-divided spectral regions(amplifi ed, de-amplifi ed and unaffected regions). Parametric studies are conducted to investigate the effects of the story stiffness of structures, the story stiffness ratio and mass ratio of adjacent buildings, the structural inelastic characteristics and the gap size values. Results show that(i) the infl uence of system stiffness ratio to the lighter and more fl exible building is more signifi cant in the fi rst spectral region, where the maximum response of the building is amplifi ed because of pounding; and(ii) the velocity and pounding force of the heavier and stiffer building is unexpectedly sensitive to the mass ratio of adjacent buildings.

关键词： pounding dimensional analysis earthquake engineeri

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基于弹性网络回归的地震动参数排序与比选

哈尔滨工业大学学报 2024年第1期56卷 54-62页

作者：刘巴黎胡进军谢礼立中国地震局工程力学研究所哈尔滨150080 中国地震局地震工程与工程振动重点实验室(中国地震局工程力学研究所) 哈尔滨150080

为合理选取地震动参数以有效减小结构损伤预测的不确定性,基于弹性网络回归技术对多个地震动参数进行了比选。基于多种地震动参数以及大量单自由度(SDOF)模型的增量动力分析结果建立弹性网络回归模型,定义回归模型中回归系数值以及回归... 详细信息

为合理选取地震动参数以有效减小结构损伤预测的不确定性,基于弹性网络回归技术对多个地震动参数进行了比选。基于多种地震动参数以及大量单自由度(SDOF)模型的增量动力分析结果建立弹性网络回归模型,定义回归模型中回归系数值以及回归系数值为非零值的个数分别为地震动参数的敏感性系数和频数。基于地震动参数敏感性和频数分析结果对多种地震动参数进行排序,研究结构恢复力模型、地震动集和结构极限状态对地震动参数排序结果的影响。基于一座8层钢框架结构分析结果验证了基于弹性网络回归的地震动参数比选方法的有效性。结果表明:选取代表性的地震动参数加入最小二乘回归模型时,不同结构极限状态下回归分析中残差标准差显著减小。基于大量SDOF体系的地震动参数排序结果比选出了受地震动集、结构恢复力模型和结构极限状态影响较小的地震动参数。结果可为结构抗震能力预测用地震动参数的比选提供理论基础。

关键词：地震动参数弹性网络回归抗震能力增量动力分析单自由度体系

Site response in the Qionghai Basin in the Wenchuan earthquake

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Earthquake Engineering and Engineering Vibration 2013年第2期12卷 195-199页

作者： Wang Haiyun xie lili Wang Suyang Ye Peng Key Laboratory of Earthquake Engineering and Engineering Vibration Institute of Engineering MechanicsChina Earthquake Administration

Amplification effects of soil site response can significantly impact ground motions, and must be considered in the seismic fortification of buildings/structures to prevent or mitigate this potential seismic hazard. Utilizing acceleration time histories from the main shock of the Wenchuan earthquake recorded at four stations （i.e., one on bedrock and three on soil） in the Qionghai Basin, the site responses from three soil sites are studied by using the traditional spectral ratio method. The bedrock site is selected as a reference site. This study found that peak ground accelerations （PGAs） on the soil sites are much larger than on bedrock, with EW, NS and UD components of 3.96-6.58, 6.27-10.98, and 3.17-6.66 times those of the bedrock site, respectively. The amplification effects of the soil sites on ground motions in the frequency range of 0.1 Hz to 10 Hz are significant, depending on the thickness of the soil layer and the frequency content of the site. A significant amplification occurs with high frequency components of ground motion at shallow soil sites, and low and high frequency components of ground motion at intermediate soil sites.

关键词： site response traditional spectral ratio method acceleration time history Qionghai Basin Wenchuan earthquake

习近平文化思想融入“概论”课教学的价值意蕴与实践进路

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高教论坛 2024年第5期 10-14页

作者：谢丽丽王小娜南宁师范大学广西南宁530001 南宁市第三十七中学广西南宁530001

探寻习近平文化思想融入“概论”课教育教学,既是完善“概论”课课程体系的内在要求,也是坚定中国特色社会主义文化自信的必然要求,更是落实立德树人根本任务的本质要求。推进习近平文化思想融入“概论”课教学,要在把握融入契合点的同... 详细信息

探寻习近平文化思想融入“概论”课教育教学,既是完善“概论”课课程体系的内在要求,也是坚定中国特色社会主义文化自信的必然要求,更是落实立德树人根本任务的本质要求。推进习近平文化思想融入“概论”课教学,要在把握融入契合点的同时,从知识、能力、价值三个维度厘定融什么的边界。在此基础上,坚持系统贯通,发挥融入主导性;坚持问题疏通,增强融入实效性;坚持方法融通,增进融入针对性;坚持课堂联通,激活融入创造性,从而在教学设计、实施过程中形成怎么融的实践进路。

关键词：习近平文化思想融入思政课教学价值实践