Institute of Earthquake Engineering

Bureau of, China

Institute of Earthquake Engineering

Bureau of, China
SEARCH FILTERS
Time filter
Source Type

Chi S.-C.,Dalian University of Technology | Chi S.-C.,Institute of Earthquake Engineering | Zhou X.-X.,Dalian University of Technology | Zhou X.-X.,Institute of Earthquake Engineering
Yantu Gongcheng Xuebao/Chinese Journal of Geotechnical Engineering | Year: 2017

The safety of core wall type rockfill dams during reservoir impounding is greatly affected by the slaking deformation of upstream shell materials. The slaking deformation of the rockfill materials is analyzed using the triaxial slaking tests, in which the specimens with natural water content are compressed to various deviatoric stress levels, and then saturated by water flow from the bottom while the stress condition remains unchanged. The results show that there is a hyperbolic relationship between the slaking axial strain and the stress level before slaking for rockfill materials. Compared with the exponential function expression for the relationship between the slaking axial strain and the stress level, the hyperbolic expression is more suitable. Plenty of test data show that the ratio between the volumetric strain increment and the axial strain increment remains constant during sample saturating. Based on the above experimental findings, a simple model is proposed for predicting the deformation of rockfill materials induced by slaking, in which, the slaking secant modulus and the slaking Poisson's ratio are expressed. Comparied with the modified Shen Zhu-jiang's slaking deformation model, the curves calculated by the proposed model are more in good agreement with the experimental data. And the research shows that the slaking deformation calculated by traditional Prandtl-Reuss flow rule is smaller than the model numerical value under the high slaking stress level. © 2017, Editorial Office of Chinese Journal of Geotechnical Engineering. All right reserved.


Zhang D.,Kunming University of Science and Technology | Zhang D.,Institute of Earthquake Engineering | Tao Z.,Kunming University of Science and Technology | Tao Z.,Institute of Earthquake Engineering | And 2 more authors.
Engineering Review | Year: 2017

In order to determine the deformation capacity of reinforced concrete composite shear wall with concealed bracings at different performance levels, some previous research of domestic scholars are reviewed by analyzing 89 shear wall specimens using a performance-based seismic design method. The performance levels of the structural element are divided into three stages to comply with the code for seismic design of buildings in China. Meanwhile, sectional plastic displacement angle under each performance level is derived and fitted within the shear span ratio ranging from 1-3. The analysis results show that average values of plastic displacement angle are about 2-3 times the corresponding ordinary shear wall, so we propose security reserve value K, as well as performance indexes of shear wall with concealed bracings according to the test data. Finally, indexes are compared with the relevant norms to provide references for China seismic design.


Yong L.I.,Chengdu University of Technology | Yan L.,Chengdu University of Technology | Shao C.,Chengdu University of Technology | Wang Z.,Chengdu Center | And 4 more authors.
Acta Geologica Sinica | Year: 2017

Depending on the analysis of the coeval sedimentary geometry and subsidence mechanism in the Longmen Shan foreland basin, three models about the coupling relationship between Longmen Shan uplift and foreland basin subsidence since the Indosinian have been proposed: (1) crustal shortening and its related wide wedge-shaped foreland basin, (2) crustal isostatic rebound and its related tabular foreland basin, and (3) lower crustal flow and its related narrow wedge-shaped foreland basin. Based on the narrow wedge-shaped foreland basin developed since 4 Ma, it is believed that the narrow crustal shortening and tectonic load driven by lower crustal flow is a primary driver for the present Longmen Shan uplift and the Wenchuan (Ms 8.0) earthquake. © 2017 Geological Society of China


Li Y.,Chengdu University of Technology | Zhou R.,Institute of Earthquake Engineering | Densmore A.L.,Durham University | Cao S.,University of Sichuan | Liu Y.,Chengdu Institute of Geology and Mineral Resources
Journal of Earthquake and Tsunami | Year: 2011

During the Ms 8.0 Wenchuan Earthquake of May 12, 2008, three distinct faults in the Longmen Shan along the eastern margin of the Tibetan Plateau ruptured. We have carried out detailed field geological mapping on these faults (the Yingxiu-Beichuan, the Pengxian-Guanxian, and the Xiaoyudong Faults), as well as the minor Leigu Fault, using GPS and total station surveys. The surface rupture of the Wenchuan Earthquake consists of two margin-parallel thrust faults linked by the Xiaoyudong tear fault. By comparing the features of the surface rupture of the faults, the spatial relationships between the different surface ruptures can be determined. It is clear that the margin-parallel thrust faults are linked at depth, forming an imbricated thrust linked by a tear fault. © 2011 World Scientific Publishing Company. © World Scientific Publishing Company.


Yu R.-F.,China Earthquake Administration | Zhou X.-Y.,Beijing University of Technology | Yuan M.-Q.,Institute of Earthquake Engineering
Jisuan Lixue Xuebao/Chinese Journal of Computational Mechanics | Year: 2013

For the generally damped linear systems with repeated eigenvalues, a hybrid approach based on the complex modal superposition method and residue matrix decomposition method is presented. The hybrid approach incorporates the merits of the modal superposition method and residue matrix decomposition method, and has clear physical concept and is easily to be understood and mastered by engineering designers to analyze the large structures. Besides, the conditions producing repeated eigenvalues for the double degrees of freedom system are deduced, and the implementation procedure of the proposed hybrid approach in the paper is illustrated by analyzing simple numerical examples. Finally, correctness and effectiveness of the formula are judged by comparing the results obtained from Newmark-β methods. It pointed out that the method derived in this paper is also suitable for linear system, electro-mechanical and control system.


Li Y.,Chengdu University of Technology | Li H.,Chinese Academy of Geological Sciences | Zhou R.,Institute of Earthquake Engineering | Su D.,Chinese Academy of Geological Sciences | And 2 more authors.
Tectonophysics | Year: 2014

Longmen Shan is located at the boundary between the Sichuan Basin and Tibetan Plateau, representing the steepest gradient of any edges of the plateau. Three endmember models of uplift process and mechanism have been proposed, including crustal thickening, crustal flow, and crustal isostatic rebound. Here, we use tectonostratigraphic units in the Late Triassic foreland basin to restraint uplift process and mechanism in the Longmen Shan during Indosinian orogeny. The Late Triassic foreland basin developed as a flexural foredeep on the Yangtze passive continental margin during the Indosinian orogeny. The basin fill includes the Maantang Formation, the Xiaotangzi Formation and the Xujiahe Formation, and it is divided into four tectonostratigraphic units with wedge-shaped or tabular cross-sectional geometry by unconformities and flooding surfaces in this paper. The first and third ones are wedge-shaped tectonostratigraphic units and correspond to underfilled condition with basal unconformities or major flooding surfaces, the high rate of subsidence and sediment accumulation, coarsening-upward succession and a dual sediment supply, and them may link to strong active thrust loading events or the rapidly advance rate of the orogenic wedge; the second and fourth ones are tabular tectonostratigraphic units and correspond to overfilled condition with the unconformity, the low rate of subsidence and sediment accumulation, fining-upward succession, a single sediment supply, the mass emergence of conglomerate layers, and they may be related to isostatic rebound and erosion unloading. Two endmember models of uplift process and mechanism in the Longmen Shan during Indosinian cycle have been proposed by coeval Late Triassic sedimentary sequences in the foreland basin here: (1) crustal thickening during the wedge-shaped tectonostratigraphic units, (2) crustal isostatic rebound during the tabular tectonostratigraphic units. This two endmember models proposed in this paper may be helpful to understand the mechanism of the Wenchuan Earthquake. © 2013 Elsevier B.V.


Yu R.-F.,China Earthquake Administration | Zhou X.-Y.,Beijing University of Technology | Yuan M.-Q.,Institute of Earthquake Engineering
Structural Engineering and Mechanics | Year: 2012

For generally damped linear systems with repeated eigenvalues and defective eigenvectors, this study provides a decomposition method based on residue matrix, which is suitable for engineering applications. Based on this method, a hybrid approach is presented, incorporating the merits of the modal superposition method and the residue matrix decomposition method, which does not need to consider the defective characteristics of the eigenvectors corresponding to repeated eigenvalues. The method derived in this study has clear physical concepts and is easily to be understood and mastered by engineering designers. Furthermore, this study analyzes the applicability of step-by-step methods, including the Newmark beta and Runge-Kutta methods for dynamic response calculation of defective systems. Finally, the implementation procedure of the proposed hybrid approach is illustrated by analyzing numerical examples, and the correctness and the effectiveness of the formula are judged by comparing the results obtained from the different methods.


Yu R.,China Earthquake Administration | Yuan M.,China Earthquake Administration | Yuan M.,Institute of Earthquake Engineering | Yu Y.,China Earthquake Administration
Applied Mechanics and Materials | Year: 2011

The U.S. Geological Survey Parkfield Dense Seismograph Array (UPSAR) successfully recorded strong motions during 2003 San Simeon earthquake (M 6.5) and 2004 Parkfield earthquake (M 6.0). Because the array covers a very small area (0.45km 2), these data offer some interesting insights into spatial variations of seismic ground motions that suits for engineering scale. in this research, we study the spatial coherency function of seismic ground motion in the horizontal and vertical directions by digital signal processing. The results show that when the circular frequency is smaller than π, the degressive trend of the coherency function becomes significant with the separation distance elongation, while the data deviation of the coherency function becomes larger with the frequency rise, which shows no obvious rules. in addition, based on the strong-motion data, a suitable spatial coherency model of ground motion is selected through comparing existing model functions, and the appropriate recommendations for improvement is put forward. Finally, according to different frequency range, the fitting parameters of the spatial coherency function of ground motion are obtained through numerical simulation. The spatial coherency function proposed in this paper is practical in simulation of ground motion field. © (2011) Trans Tech Publications.


Yu R.,China Earthquake Administration | Zhou X.,Beijing University of Technology | Yuan M.,Institute of Earthquake Engineering
Advanced Materials Research | Year: 2012

For general damped linear systems with multiple eigenvalues, this study provides a practical step-by-step procedure of the high-order dynamic response analysis. The method derived in this study has clear physical concepts and is easily to be understood and mastered by engineering designers. Moreover, a numerical example is used to analyze the correctness and the effectiveness of the new method by comparing the calculation results with the theory solution.


Yu R.F.,China Earthquake Administration | Abduwaris A.,China Earthquake Administration | Yuan M.Q.,Institute of Earthquake Engineering | Yu Y.X.,China Earthquake Administration
International Efforts in Lifeline Earthquake Engineering - Proceedings of the 6th China-Japan-US Trilateral Symposium on Lifeline Earthquake Engineering | Year: 2014

Zigong Seismograph Array (ZGSA) locates in Sichuan province of China, which was installed in 2007 and included 8 irregularly spaced seismograph stations. The array successfully recorded strong motions during 2008 Wenchuan earthquake (Ms 8.0). Because the separation distances between every two stations are less than 400 meters, these data offer some interesting insights into spatial variations of seismic ground motions that suits for engineering scale. In this study, authors firstly calculated the coherency functions of accelerations at different directions recorded by ZGSA through application of digital signal processing technology. Then, the variation mechanisms of the coherency functions at various directions along with the separation distance and frequency changes were analyzed. The results showed that when the circular frequency was less than 3, the coherency function was more than 0.8. However the degressive trend of the coherency function became significant with the separation distance elongation when frequency gradually increased. Consequently, based on the recordings, a piecewise fitting model was put forward to simulate the spatial variation of seismic ground motion under the conditions of large-earthquake and far-field. The spatial coherency model proposed in this paper has applicable value in simulation study of ground motion field.

Loading Institute of Earthquake Engineering collaborators
Loading Institute of Earthquake Engineering collaborators