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On time-step in structural seismic response analysis under ground displacement/acceleration

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Earthquake Engineering and Engineering Vibration 2009年第3期8卷 341-347页

作者： TianYuji~+ and Yang Qingshan~(++) School of Civil Engineering,Beijing Jiaotong University,Beijing 100044,China +associate professor ++professor School of Civil Engineering Beijing Jiaotong University Beijing 100044 China

There are two models in use today to analyze structural responses when subjected to earthquake ground motions, the Displacement Input Model （DIM） and the Acceleration Input Model （AIM）. The time steps used in direct integration methods for these models are analyzed to examine the suitability of DIM. Numerical results are presented and show that the time-step for DIM is about the same as for AIM, and achieves the same accuracy. This is contrary to previous research that reported that there are several sources of numerical errors associated with the direct application of earthquake displacement loading, and a very small time step is required to define the displacement record and to integrate the dynamic equilibrium equation. It is shown in this paper that DIM is as accurate and suitable as, if not more than, AIM for analyzing the response of a structure to uniformly distributed and spatially varying ground motions.

关键词： integration time step multi-supported structure displacement input model acceleration input model spatially varying ground motions

Preliminary analysis of the hanging wall effect and velocity pulse of the 5.12 Wenchuan earthquake

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Earthquake Engineering and Engineering Vibration 2009年第2期8卷 165-177页

作者： Liu Qifang and Li Xiaojun Institute of Engineering Mechanics, China Earthquake Administration, Harbin 150080, China associate professor professor Institute of Engineering Mechanics China Earthquake Administration Harbin 150080 China Institute of Engineering Mechanics China Earthquake Administration 9 Xuefu Road Harbin 150080 China

A preliminary study of the PGA attenuation, hanging wall effect and velocity pulse characteristics from the 2008 Wenchuan earthquake ofMS -8.0 is described in this paper. The study was carried out through analyses in the time and frequency domains of main earthquake records. In the PGA attenuation study, records from 316 stations less than 1000 km from the surface rupture of the fault were used as a database and attenuation relationships were developed and compared with some existing relationships that are widely used in China's Mainland, Chinese Taiwan and the US. At the same time, records from 28 stations less than 100 km from the fault were used to study the hanging wall effect and velocity pulse characteristics of this earthquake based on the distribution of PGA, PGV, spectral acceleration, and the velocity pulse peak, and the results are compared with the 1999 Chi-Chi earthquake. In addition, the large PGAs of the UD components observed in this event are also discussed in this paper. From the results of the preliminary study, some conclusions are developed and suggestions for further research are proposed.

关键词： Wenchuan earthquake hanging wall effect velocity pulse attenuation

COMPARISON BETWEEN RESULTS OF MODEL TESTS AND OBSERVED DATA FOR THE FLUCTUATING BACKWATER REGION OF THE GEZHOUBA RESERVOIR

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International Journal of Sediment Research 1991年第1期6卷 73-81页

作者： WANG Guixian,CHEN Zhicongand ZHANG Ren associate professor, Tsinghua University. associate professor, Tsinghua University professor, Tsinghua University.

The fluctuationg backwater region of a reservoir has a twofold property of a river as well as a reservoir and undergoes scouring and deposition alternately. Phys- ical model simulating the fluvial processes in a fluctuating backwater region has to ensure the similarities of both scouring and deposition. This causes some difficulties in model design and the selection of model sediment. This paper describes the model study of the fluctuating backwater region of the Gezhouba Project on the Yangtze River. Plastic particles with specific gravity of 1 .056 are used. The physical. model covers a reach of mountainous river 130 km in length. The experimental results show that the total amount of deposit, its distribution along the reach, the size distribution of the deposit, and lengths of the backwater region for various discharges all agree very well with the measured data in reservoir after 5 years of operation. This fact indicates that the model design, including the selection of model sediment, is quite acceptable.

关键词： Fluctuating backwater region Model test. Size distribution Verification test Bed material load Wash load. Incipient velocity Settling velocity

Emergency assessment of seismic landslide susceptibility: a case study of the 2008 Wenchuan earthquake affected area

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Earthquake Engineering and Engineering Vibration 2009年第2期8卷 207-217页

作者： Tang Chuan,Zhu Jing and Liang Jingtao State Key Laboratory of Geo-Hazard Prevention,Chengdu University of Technology,Chengdu 610059,China professor associate professor Graduate Student State Key Laboratory of Geo-Hazard Prevention Chengdu University of Technology Chengdu 610059 China

The 8.0 Mw Wenchuan earthquake triggered widespread and large scale landslides in mountainous regions. An approach was used to map and assess landslide susceptibility in a given area. A numerical rating system was applied to five factors that contribute to slope instability. Factors such as lithology, topography, streams and faults have an important influence as event-controlling factors for landslide susceptibility assessment. A final map is provided to show areas of low, medium, and high landslide susceptibility. Areas identified as having high landslide susceptibility were located in the central, northeastern, and far south regions of the study area. The assessment results will help decision makers to select safe sites for emergency placement of refuges and plan for future reconstruction. The maps may also be used as a basis for landslide risk management in the study area.

关键词： landslide susceptibility GIS Wenchuan earthquake Qingchuan area

Improoing Finges' Functiong of Mental Students by Combining Medicine with Education and Physical Education

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北京体育大学学报 1995年第S2期18卷 67-73页

作者： LIU Shaozeng (54 years old, associate professor)

The improvement of fingers’functions is important for mentalretarded students to enhance their living,learning and working abilities. The study showed through experiments that adopting a method combining medicine with physical education and education can lead to a better improvement of fingers’ functions of the mental retarded students.

关键词： finger function moving range of finger joint means combining medicine with physical education and education

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China Ocean Engineering 1988年第3期2卷 91-100页

作者： Tao Mingde associate professor, Fudan University, Shanghai. China

It is assumed that the angle included between the crest line and the shoreline is variable in the problem of the littoral transport. A nonlinear partial differential equation is derived and the equation is reduced to a nonlinear ordinary differential equation using the method of one-parameter groups of tram-formations. The asymptotic solutions to the problem of a spur dike are obtained. From the results it can be seen that the growth of the shoreline appears fast, which could be explained logically.

关键词： SIMILAR SOLUTIONS TO SHORELINE EVOLUTION DUE TO SPUR DIKES

Neigong Science:A Gem in the East Physical Culture

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北京体育大学学报 1995年第S2期18卷 9-13页

作者： LIN Boyuan (43 years old, associate professor)

Neigong (internal execist) in a kind of exercise for health promotion through adjusting body, breath,mind and raising the extent of being in order of the body. The theory of neigong was developed on the basis of Chinese philosophic thought of maintaining softness, calmness and desireless, Chinese medical theory of internal organ channels, and various schools of daoyin breathing. Its research scope includes both fit-keeping exercises and wushu internal exercises. The practice of neigong emphasizes self-consciousness of the main body, an organic conception of the heaven and the man, calmness, and a return to the original essenee. Combining still with motion and making conces sion for advantages, the exercise is charecterizes by an inward inclined detachment. Neigong in China and similar exercises appeared in other Asian countries and areas represents a major school of the Oriental physical

关键词： internal exercise adjusting berath wushu daoyin inward inclined detachment an organic conception of the heaven and the man

Long-Term Joint Distribution of One-Tenth Large (or Significant) Wave Height with Average Period

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China Ocean Engineering 1992年第4期7卷 383-394页

作者： Pan Jinchang associate professor, Dalian University of Technology, 116024 Dalian

In this paper, by using the wave data from a few oceanographic observation stations in the coastal zone of the Yellow Sea, the East China Sea and the South China Sea, the long-term joint distribution of the one-tenth large (or significant) wave height with average period is studied. The statistical data demonstrate that the long- term distribution of the one- tenth wave height or average period fits the log-normal distribution, thus the joint distribution also fits the two-dimensional log-normal distribution. Then the conditional probability distribution of the average period is derived, and the range as well as the mode of the average wave period corresponding to a certain return period of wave height can be calculated easily.

关键词： joint distribution wave height average period probability

Experimental investigation of damage behavior of RC frame members including non-seismically designed columns

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Earthquake Engineering and Engineering Vibration 2009年第2期8卷 301-311页

作者： Chen Linzhi,Lu Xilin,Jiang Huanjun and Zheng Jianbo State Key Laboratory of Disaster Reduction in Civil Engineering,Tongji University,Shanghai 200092,China PhD Candidate professor associate professor Master of Engineering State Key Laboratory of Disaster Reduction in Civil Engineering Tongji University Shanghai 200092 China State Key Laboratory of Disaster Reduction in Civil Engineering Tongji University 1239 Siping Road Shanghai 200092 China

Reinforced concrete （RC） frame structures are one of the mostly common used structural systems, and their seismic performance is largely determined by the performance of columns and beams. This paper describes horizontal cyclic loading tests often column and three beam specimens, some of which were designed according to the current seismic design code and others were designed according to the early non-seismic Chinese design code, aiming at reporting the behavior of the damaged or collapsed RC frame strctures observed during the Wenchuan earthquake. The effects of axial load ratio, shear span ratio, and transverse and longitudinal reinforcement ratio on hysteresis behavior, ductility and damage progress were incorporated in the experimental study. Test results indicate that the non-seismically designed columns show premature shear failure, and yield larger maximum residual crack widths and more concrete spalling than the seismically designed columns. In addition, longitudinal steel reinforcement rebars were severely buckled. The axial load ratio and shear span ratio proved to be the most important factors affecting the ductility, crack opening width and closing ability, while the longitudinal reinforcement ratio had only a minor effect on column ductility, but exhibited more influence on beam ductility. Finally, the transverse reinforcement ratio did not influence the maximum residual crack width and closing ability of the seismically designed columns.

关键词： reinforced concrete frame member cyclic test hysteresis behavior damage behavior seismic performance