Wuhan Institute of Earthquake Engineering

Wuhan, China

Wuhan Institute of Earthquake Engineering

Wuhan, China
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Li H.,China Earthquake Administration | Li H.,Wuhan Institute of Earthquake Engineering | Chen F.,Tianjin Geological Engineering Prospecting Institute
Geodesy and Geodynamics | Year: 2017

DMF (Damping modification factors) are used to modify elastic response spectral values corresponding to damping ratio 5% to other damping levels. The influence of seismological parameters (magnitude, epicentral distances and site conditions) on DMF for acceleration spectra was analysed. The results show that for a given period as the magnitude or distance increase, the effect of damping on the seismic response will also increase, which indicates the response reduction from the structural damping will become more efficient. In the near-field of small earthquakes, the influence of site conditions on DMF is obvious, but it does not show a consistent rule. Furthermore, the DMF corresponding to different site conditions gradually close to unity with increasing magnitude and distance. The influence of the above mentioned parameters is related to the relative attenuation of the frequency components of the ground motion. The attenuation index alone is sufficient to take into account the influence. Based on these features, this paper proposes a formula of DMF for acceleration response spectra. © 2017 The Authors.


Li H.,China Earthquake Administration | Li H.,Wuhan Institute of Earthquake Engineering | Li L.,China Zhongtie Major Bridge Reconnaissance and Design Institute Co. | Feng Q.,China Earthquake Administration | Feng Q.,Wuhan Institute of Earthquake Engineering
Journal of Earthquake Engineering and Engineering Vibration | Year: 2012

The effect of the long-period filter cut-off, Tc, on spectral displacements is analysed using the NGA database of the Pacific Earthquake Engineering Research Center. Long-period spectral displacements would be suppressed badly, if a short Tc is chosen. Strong ground motion accelerograms with reliable period up to at least 10s are selected to investigate the characteristics of displacement response spectra at long periods. The results indicate that the period, in which the spectral displacement culminates, is a significant parameter to control long-period spectral ordinates. This parameter can't be affected obviously by site condition and magnitude,but greatly depends on epicentral distance with linear relation. The maximum amplification factor of displacement spectrum fluctuates slightly, and can be treated as a constant. A transition region is suggested to insert between velocity-sensitive region and displacement-sensitive region to fit for displacement spectrum, and the values of some parameters are proposed in this paper.


Kong Q.,University of Houston | Feng Q.,China Earthquake Administration | Feng Q.,Wuhan Institute of Earthquake Engineering | Song G.,Dalian University of Technology
International Journal of Smart and Nano Materials | Year: 2015

Liquid migrating into existing concrete cracks is a serious problem for the reliability of concrete structures and can sometimes induce full concrete structural failures. In this paper, the authors present recent research on water presence detection in concrete cracks using piezoceramic-based smart aggregate (SA) transducers. The active sensing approach, in which one piezoceramic transducer is used to generate stress waves and others are used to detect the stress wave responses, is adopted in this research. Cracks formed in concrete structures act as stress reliefs, which attenuate the energy of the signals received by the SAs. In case of a crack being filled with liquid, which changes the wave impedance, the piezoceramic transducers will report higher received energy levels. A wavelet packet-based approach is developed to provide calculated energy values of the received signal. These different values can help detect the liquid presence in a concrete crack. A concrete beam specimen with three embedded SAs was fabricated and tested. Experimental results verified that the SA-based active sensing approach can detect a concrete crack and further detect the liquid presence in the concrete crack. © 2015 The Author(s). Published by Taylor & Francis.


Cheng L.,Wuhan University | Cheng L.,Wuhan Institute of Geology and Mineral Resources | Chen X.,Wuhan Institute of Geology and Mineral Resources | Zeng X.,Wuhan Institute of Geology and Mineral Resources | Cai Y.,Wuhan Institute of Earthquake Engineering
Journal of Earth Science | Year: 2012

A new eosauropterygian, Largocephalosaurus polycarpon gen. et sp. nov., was described based on a skeleton from the Middle Triassic of Luoping (Chinese source), Yunnan (Chinese source) Province, southwestern China. The new taxon is characterized by a big skull, paired frontal, laterally expanded upper temporal fossa, anterior process of squamosal entering orbit, robust teeth with basally expanded crown and blunt tip, short cervical region, distinctly elongated transverse process of the dorsal vertebrae, short and broad dorsal ribs, stout gastralia, scapula with distinctly posterodorsally extending blade, distinctly robust humerus, eleven carpal ossifications, and a manual fomula of 2-3-4-5-5. A phylogenetic analysis suggests that Largocephalosaurus is the basal-most member of a clade including Wumengosaurus, European pachypleurosaurs, and Nothosauroidea. © 2012 China University of Geosciences and Springer-Verlag Berlin Heidelberg.


Feng Q.,China Earthquake Administration | Feng Q.,Wuhan Institute of Earthquake Engineering | Kong Q.,University of Houston | Song G.,University of Houston
Measurement: Journal of the International Measurement Confederation | Year: 2016

Concrete piles are the most common types of foundation structures. Pile damages, such as fractures, cracks, mud intrusion and secondary concrete pouring, are the leading causes of pile structural failure, which may directly result in casualties and economic loss. It is desirable to develop a monitoring system that can detect these pile damages. In this paper, embedded piezoceramic-based smart aggregates transducers along with the active sensing approach are developed to detect common types of pile damages, including crack, partial mud intrusion, secondary pouring, and full mud intrusion, based stress wave measurement. With the active sensing approach, one smart aggregate is used as an actuator to generate a stress wave that will propagate along the pile, and other smart aggregate(s) will measure the propagating wave. All damages, which introduce new interfaces and discontinuities, attenuate the stress wave propagation. The attenuations of the stress waves based on different pile damages were compared by the received sensor signal in time domain. A wavelet packet-based energy analysis was used to develop an energy index to assist the detection of damages. Experimental results demonstrated the feasibility that the proposed approach can detect all four types of common damages associated with concrete piles. © 2016 Elsevier Ltd


Cheng L.,Wuhan University | Cheng L.,Wuhan Institute of Geologyand Mineral Resources | Chen X.,Wuhan Institute of Geologyand Mineral Resources | Zhang B.,Wuhan Institute of Geologyand Mineral Resources | Cai Y.,Wuhan Institute of Earthquake Engineering
Acta Geologica Sinica | Year: 2011

The skul1 of Anshunsaurus huangnihensis Cheng, 2007, especially the skul1 roof, is described in detai1 in this paper. Compared to other genera and species of Askeptosauroidea, Anshunsaurus huangnihensis has some important transitiona1 characters from Askepiosaurus iialicus to Anshunsaurus huangguoshuensis: the rostra1 length related to the skull length between Askepiosaurus iialicus and Anshunsaurus huangguoshuensis; the postfrontal existing but distinctly reduced; the posterolatera1 process relatedly short and overlapping the parietal. The phylogenetic analysis weakly supports the evolutiona1 progress from Anshunsaurus huangnihensis to Anshunsaurus huangguoshuensis. The skeleta1 ratios indicated that the node among the Askeptosauridae ingroup. The evolutional direction of Askeptosauridae should be from Askepiosaurus iialicus to Anshunsaurus huangguoshuensis. The skeleta1 ratios indicated that the evolutiona1 progress is Askepiosaurus italicus -Anshunsaurus huangnihensis -Anshunsaurus huangguoshuensis. In biogeography provinces, the Askeptosauroidea taxa from south China have a close relationship with those from western Tethys; however, Xinpusaurus from the Late Triassic is more related to those from the eastern Pacific.


Zhang X.,Chongqing Jiaotong University | Zhang Y.,Institute of Seismology | Zhang Y.,Wuhan Institute of Earthquake Engineering
Wuhan Ligong Daxue Xuebao (Jiaotong Kexue Yu Gongcheng Ban)/Journal of Wuhan University of Technology (Transportation Science and Engineering) | Year: 2012

Steel truss carriage, which was used as the transfer equipment of heavy cargoes for sloping wharves, had different stress state, because of various handling technology. According to three types of handling technology for Xiangjiaba heavy cargo wharf, three types of working conditions were defined. The third condition was considered the most unfavorable, after the stress and deformation calculation. Through the comparison analysis of setting stiffening plates or not, the conclusion was drawn that the plates were effective on developing the holistic structure rigidity, reducing stress, and controlling deformation. The optimal program was put forward that the stiffening plates should be arranged alternately. The optimal model and computation analysis showed that the alternate arrangement of the plates meet the requirement of the safety and economy. The stress and deformation were under the allowable value of standard code. The optimal program was proved feasible.


Li H.,China Earthquake Administration | Li H.,Wuhan Institute of Earthquake Engineering | Qin X.,China Earthquake Administration
Journal of Earthquake Engineering and Engineering Vibration | Year: 2010

In this paper, 3225 strong ground motion records from 128 earthquakes are used to calculate the ratios of the vertical to horizontal acceleration response spectra ( V/H). The records are divided into groups according to site condition, epicentral distance, magnitude and focal mechanism. This study focuses on the relationship between V/ H and these factors. The results show that : (1) the harder the site is, the larger the V/H in long-period range becomes , and the V/H in short-period range is opposite. (2) The greater the magnitude is, the higher the V/H in long-period range becomes, but the V/H in short period is not impressible. (3) The V/H in short period decreases as epicentral distance increases. (4) For great magnitude (M >7) , the V/H in long-period range reduces as the epicentral distance increases. However, for great-moderate earthquakes (M <7) , the ratio increases with the epicentral distance in near-field, and it reduces as the epicentral distance increases in far-field. (5) The V/H is also related to focal mechanism.


Feng Q.,China Earthquake Administration | Feng Q.,Wuhan Institute of Earthquake Engineering | Feng Q.,University of Houston | Kong Q.,University of Houston | And 3 more authors.
Smart Materials and Structures | Year: 2015

Reinforced concrete underground pipelines are some of the most widely used types of structures in water transportation systems. Cracks and leakage are the leading causes of pipeline structural failures which directly results in economic losses and environmental hazards. In this paper, the authors propose a piezoceramic based active sensing approach to detect the cracks and the further leakage of concrete pipelines. Due to the piezoelectric properties, piezoceramic material can be utilized as both the actuator and the sensor in the active sensing approach. The piezoceramic patch, which is sandwiched between protective materials called 'smart aggregates,' can be safely embedded into concrete structures. Circumferential and axial cracks were investigated. A wavelet packet-based energy analysis was developed to distinguish the type of crack and determine the further leakage based on different stress wave energy attenuation propagated through the cracks. © 2015 IOP Publishing Ltd.


Hu Q.,Institute of Seismology | Hu Q.,Wuhan Institute of Earthquake Engineering | Yang G.,Institute of Seismology | Yang G.,Wuhan Institute of Earthquake Engineering | And 4 more authors.
Electronic Journal of Geotechnical Engineering | Year: 2016

On the basis of the deep borehole profile near Yangtze River in Wuhan City, eight interfaces of soil layers, whose shear wave velocities range from 414 to 912 m·s-1, are selected as the seismic wave input interfaces. Effects of input interface on ground motion parameters are analyzed with one-dimension equivalent linear method by choosing Taft,Lushan and Kobe strong motion records as seismic input. The results of seismic soil-response show that: (1) Peak ground acceleration(PGA) increases with the growth of depth and shear wave velocity of the input layer, but rising rate gradually decreases. (2) Ground motion characteristic period of response spectrum(Tg) changes little as depth or shear wave velocity of the input layer increases. (3) Curves of surface acceleration response spectra gradually rise with the increase of input depth, but rising magnitude slows down. High-frequency components of response spectra weaken while low-frequency ones enrich if the intensities of input seismic motion enhance. (4) For buildings with moderate-long natural vibration periods on deep sites, soil layers with shear wave velocity not less than 600m·s-1can be chosen as input seismic interface. © 2016 ejge.

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