Northwest Center for Disaster Mitigation in Civil Engineering

Lanzhou, China

Northwest Center for Disaster Mitigation in Civil Engineering

Lanzhou, China
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Zhou F.,Northwest Center for Disaster Mitigation in Civil Engineering | Li S.,Yangzhou University
Lixue Xuebao/Chinese Journal of Theoretical and Applied Mechanics | Year: 2010

The state equation of functionally graded rectangular plate were established with the state variables of three displacement components and three stress components, based on the three-dimensional linear elastic theory by using of state space method. Considering simply supported boundary conditions, the static bending and free vibration problems of a three-dimensional functionally graded rectangular plate were numerically solved by shooting method with that the material properties through the thickness coordinate are assumed to obey the exponent law dependence. Effects of the volume fraction distributions of constituent materials, and thickness-to-side ratio of functionally graded rectangular plate on the dynamical and static responses were studied. The present algorithm can be used to research the three-dimensional elastic response of functionally graded materials.


Liu Y.,Guangzhou University | Liu Y.,Beijing University of Technology | Tan P.,Guangzhou University | Zhou F.,Guangzhou University | And 3 more authors.
Advanced Materials Research | Year: 2011

Based on the configuration and mechanical characteristics of piezoelectric actuator, the bidirectional piezoelectric variable friction control device which can produce control force in two orthogonal directions was designed and the relation equation of control force with input voltage for this control device was presented. Finally, one piezoelectric variable friction control device was manufactured and performance test of this control device was processed. The result of numerical analysis and experiment shows the bidirectional piezoelectric variable friction control device can produce semi-active control force fast, and the performance of this control device do not change when the frequency of input excitation varies and the control force of this control device has stable mechanical properties. © (2011) Trans Tech Publications.


Liu Y.-H.,Guangzhou University | Tan P.,Guangzhou University | Zhou F.-L.,Guangzhou University | Du Y.-F.,Northwest Center for Disaster Mitigation in Civil Engineering | Yan W.-M.,Beijing University of Technology
Gongcheng Lixue/Engineering Mechanics | Year: 2015

A dynamic model for isolated high-rise frame-shear wall buildings was presented based on the consideration of interaction of frame and shear wall, in which the shear wall is a system with distributed mass and the frame is a system with lumped mass and spring. According to established dynamic model, the effects of isolated devices and the frame structure on the shear wall structure were introduced into a distributed parameter system using boundary conditions, and frequency equation and mode orthogonal conditions were deduced. Then, according to the Hamilton Principle, the equivalent damping ratio in every mode produced by the damping of laminated rubber bearings was derived, and the seismic response of isolated high-rise frame-shear wall buildings can be obtained by the mode superposition method. Finally, a ten-story isolated frame-shear wall building was chosen to analyze dynamic characteristics and seismic response to validate the correctness of the dynamic model and method of solving for seismic response. Simulation results show that the established dynamic model can reflect the dynamic performance of isolated structure well and seismic response of isolated high-rise frame-shear wall buildings can be solved conveniently by the method in this paper, the results of which are basically consistent with those from finite element methods. At the same time, the method deduced can obtain the interaction process of frame structures and shear-wall structures in isolated high-rise frame-shear wall buildings. ©, 2015, Tsinghua University. All right reserved.


Liu Y.-H.,Guangzhou University | Liu Y.-H.,Beijing University of Technology | Du Y.-F.,Northwest Center for Disaster Mitigation in Civil Engineering | Zhou F.-L.,Guangzhou University | And 3 more authors.
Gongcheng Lixue/Engineering Mechanics | Year: 2011

In base-isolated tall shear wall buildings, the bidirectional anti-pulling sliding device is used to resist tension and bear pressure. In this paper, it was developed and used together with the laminated rubber bearing to form a composite base-isolation system. Based on the established dynamic mechanical model of this base-isolated system, the frequency equation, mode orthogonal conditions, generalized mass and stiffness were deduced. According to the Hamilton principle, the equivalent damping ratio in each mode produced by the damping of laminated rubber bearings was derived. Therefore, the seismic response of base-isolated tall shear wall buildings can be solved by the modal superposition method. The seismic response of a sixteen-story base-isolated shear wall building was obtained by establishing a dynamic model and carrying out analysis against that model, demonstrating that this composite isolated system has an obvious function of shock absorption, thus the bidirectional anti-pulling sliding device can resist tension produced by over-turning moment. In addition, the seismic response obtained through the established dynamic model in this paper was basically consistent with that by numerical integration solution of FEM, showing the correctness of the established dynamic model and the solving method.


Lei Y.-Q.,Northwest Center for Disaster Mitigation in Civil Engineering | Lei Y.-Q.,Lanzhou University of Technology | Du Y.-F.,Northwest Center for Disaster Mitigation in Civil Engineering | Du Y.-F.,Lanzhou University of Technology
Zhendong yu Chongji/Journal of Vibration and Shock | Year: 2014

In allusion to the sensors failure in vibration control system in huge engineering structures, the methods of dynamic characteristic identification and sensor failure detection of control system were proposed based on multi-channel RBF neural network, and a smart active fault tolerant control algorithm was presented for huge engineering structures. The mutual interference between normal sensor and failure sensor in the process of sensor failure detection was solved by decomposing the sensor feedback signals into multi-channel signals in dynamic characteristic identification. When sensors work normally, the controller calculates the control force according to the preset control algorithm. When any sensor fails, the control system will get rid of the failure sensor signal automatically and the controller will switch to the control algorithm which considers this sensor's failure. The effectiveness and superiority of the sensor failure detection strategy and the presented smart active fault control algorithm based on multi-channel RBF neural network were proved by the simulation of Benchmark model controlled by AMD under earthquake.


Xiang C.-S.,Lanzhou University of Technology | Xiang C.-S.,Northwest Center for Disaster Mitigation in Civil Engineering | Jiang L.,China Railway 21st Bureau Group Co. | Li Q.-F.,Lanzhou University of Technology
Applied Mechanics and Materials | Year: 2012

The welding quality of the steel structure is one of the most important segments in the whole construction project, especially in the condition of special geographical environment and wicked climate. In this article, by means of the mechanical test and finite element simulation analysis, a welding treating technology has been summarized in the subzero surrounding, which is based on the fundamental of component size selecting, preheat, heat preservation, and change of the ambient temperature including the rising material temperature before welding. Therefore the thermal crack and cold crack can been effectively eliminated. Rigorous controlling the temperature of the welding procedure and scientific construction play an important role to ensure the welding quality of the big span truss beam and column. © (2012) Trans Tech Publications, Switzerland.


Zhu Y.-P.,Lanzhou University of Technology | Zhu Y.-P.,Northwest Center for Disaster Mitigation in Civil Engineering | Li J.-B.,Lanzhou University of Technology | Li J.-B.,Northwest Center for Disaster Mitigation in Civil Engineering | And 4 more authors.
Gongcheng Lixue/Engineering Mechanics | Year: 2015

In the area of Longnan, Gansu province, slope engineering safety issues have become increasingly prominent, and it is necessary to monitor and warn the slope works. A comprehensive three-dimensional automatic slope monitoring system was established, based on a high slope reinforcement works instance of Zhouqu reconstruction project after a disaster. Through monitoring and analyzing on the slope of stress and displacement, we found the slope's changes in the characteristics and laws during the construction and operational phases. During the initial phrase, the slope support, stress, and displacement amplitude are greater. With the mutual adjustment of internal support structure and rock slope, both changes were stabilized. Since the end of the slope support, maximum displacement speed is 0.24 mm/d,<0.5 mm/d, and maximum displacement accumulated variation is less than 10mm. Maximum acceleration is 0.31 mm/d2; the force and deformation of lattice beams are in the elastic range; the slope changes of internal horizontal displacement are small. Integrated the monitoring results, it can be drawn that an anchor lattice beam can play an effective reinforcement role, and that during the operational phase, this slope is in a stable state. The test has certain reference value for the reinforcement design and monitoring analysis of similar slopes in the future. ©, 2015, Tsinghua University. All right reserved.


Duan W.-Z.,Construction Supervision Company of Gansu province | Li L.,Lanzhou University of Technology | Li L.,Northwest Center for Disaster Mitigation in Civil Engineering | Han J.-P.,Lanzhou University of Technology | And 4 more authors.
Advanced Materials Research | Year: 2013

The temperature control including environmental temperature, preheating temperature, post-heating temperature is the main factors to reduce the welding residual stresses and lower heat influence zone at welding line. Their three relationship are discussed in this article, and optimized by the means of the field test and practical operation, a series of construction points and supporting measures has be summarized at the 'Dun-huang station project' and 'Yu-zhu project', which is proved very effective and can be applied at the similar environmental district. © (2013) Trans Tech Publications, Switzerland.


Zhu Y.-P.,Lanzhou University of Technology | Zhu Y.-P.,Northwest Center for Disaster Mitigation in Civil Engineering | Yang X.-H.,Lanzhou University of Technology | Yang X.-H.,Northwest Center for Disaster Mitigation in Civil Engineering | And 3 more authors.
Gongcheng Lixue/Engineering Mechanics | Year: 2015

After earthquakes, most of gravity retaining walls in the earthquake zone emerge an instability phenomenon, and due to the change of the retaining wall working conditions, instable accidents might be produced. Thusly, the framework anchor with flexible prestress was used to reinforce gravity retaining walls. On the basis of limit equilibrium theory, the overall static stability of gravity retaining wall after flexible reinforcement was analyzed, and the solution formula for the safe stability coefficient of anti-slip and anti-overturning was derived. The dynamic formula of stability was also derived by energy analysis and limit equilibrium theory. Based on the comparative analysis of numerical examples, the result showed that: the safe stability coefficient of reinforced gravity retaining walls was significantly improved, and the aseismic capacity of space synergy among soil, framework, anchor, and retaining walls was also improved respectively. © 2015, Engineering Mechanics Press. All right reserved.


Ye S.-H.,Northwest Center for Disaster Mitigation in Civil Engineering | Ye S.-H.,Lanzhou University of Technology | Zhu Y.-P.,Northwest Center for Disaster Mitigation in Civil Engineering | Zhu Y.-P.,Lanzhou University of Technology | And 2 more authors.
Yantu Gongcheng Xuebao/Chinese Journal of Geotechnical Engineering | Year: 2011

Taking a complicated foundation pit in Lanzhou as the background, the application of soil nailing walls, composite soil nailing walls and pile-prestressed anchors are respectively introduced, and the key construction technology is discussed. The monitoring results show that, the design scheme for the supporting is reasonable, the effectiveness is good, and the requirements of design and environment are satisfied. The experience of this project is significant to similar projects in Lanzhou.

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