Wei Ming Yan

Aseismic Constitution Problems and Strengthening Methods of Chinese Ancient Wooden Buildings

Chinese ancient wooden buildings have good aseismic constitutions to survive sorts of natural disasters. However, under earthquakes damages still occur on some of them. To protect Chinese ancient wooden buildings, typical aseismic constitution problems as well as strengthening methods of their members were studied by classification and statistical methods. Based on survey results on large number of Chinese ancient wooden buildings, typical aseismic constitution problems were summed up, causes for the problems were analyzed and the corresponding strengthening methods were proposed. By 2 compared examples, typical strengthening methods were further demonstrated. Results show that typical aseismic constitution problems of Chinese ancient wooden buildings include decay of column root, slack of Tou-Kung, tenon pulled out of mortise, cracks of beam and column and so on; to solve these problems, methods such as replacement, wrap, connection, ensemble and so on are feasible.

Construction of Zhoutouzui Immersed Tunnel in China

Immersed tunnel was constructed in the year 1910 at the first time. The next few decades, there were more than one hundred immersed tunnels constructed in the world. Zhoutouzui Immersed Tunnel of Guangzhou City is the seventh underwater tunnel in Chinese Mainland. It is one concrete tunnel with rectangular cross-section which is variable because of the constraint conditions at overpass. It has distinct feature in Chinas tunnel design. The overall design and technical characteristics of Zhoutouzui Immersed Tunnel are described in detail.

Effect of Laminar Flow to Velocity Exponent of Viscous Damper

The relationship between the energy dissipation and the damping force is studied through experimental and analytical research of the effect of laminar flow of viscous damper, and a linear viscous damper model and the calculation formulas are obtained.The results show that the linear flow model is the key factor to get a linear relationship between speeds and damping force.

Seismic Analysis of a Low Tower Cable-Stayed Bridge and Application of Lead Shear Damper

A low tower cable-stayed bridge with a span of 30m+60m+120m+60m+30m had been built before Guidelines for Seismic Design of Highway Bridge was promulgated. Because of its impor¬tance and specificity, it is necessary to do research on seismic performance of this bridge. According to the numerical analysis, it is found that the structural response exceeds the allowance and the bridge might be destroyed if earthquake happened. Here, energy dissipated technology is chosen to cope with this problem. But traditional lead shear damper hasn’t the capabilities of large deformation for some reason and can not be applied to bridge engineering in general case. In this article, a new type of lead shear damper with capabilities of large deformation is used to achieve energy dissipation. Through comparing, it is found that the damping effect of this new damper is as good as that of viscous damper. And the damper has no problem with leakage and metamorphism. What’s more, it is much cheaper than vis¬cous damper. So, lead shear damper has a good prospect in bridge damping.

Temperature Analysis in Durability Test of the Viscous Damper

The cylinder is prone to be damaged due to temperature increasing in vibration control and durability testing process of viscous damper. In order to avoid the overheating generated by long working hours, which resulting in a viscous liquid water evaporation and leading to a abrupt increase in internal pressure inside the cylinder, the CFD software Fluent was used to simulate the durability test process of the oil film, where the heat was easy to generate and suggestion for improving the viscous damper was proposed.

Integration, Application and Analysis of the SHM System for Continuous Rigid Frame Bridge

This paper is aiming to present the whole situation of a three spans prestressed continuous concrete rigid frame bridge’s SHM (structural health monitoring) system. Hardware structure and software exploitation of the system were respectively elaborated combining with the practical application situation, including details of sensors layout, data acquisition, storage and transform, the developing of monitoring and management system, etc. Emphasis is placed on data processing and analyzing which is collected from the bridge in the online continuously, such as modal identification of the measured acceleration responses, calculation of deflection curves in real time, observation of changing strains and stresses on the measuring points.

Friction Pendulum TMD and its Control Effectiveness for Wind-Induced Vibration

A new type of frictional pendulum TMD is designed. The wind-induced vibration of Henan Art Center Symbolic Tower with and without TMD is analyzed. The structural design of frictional pendulum TMD is presented in detail. The equivalent analysis model is established. The 3D analysis of the symbolic tower is established using SAP2000. The non-linear LINK unit in SAP2000 is used to simulate frictional pendulum TMD. Then, the non-linear analysis of wind control effectiveness of frictional pendulum TMD is carried out. The analysis results demonstrate that optimal frictional force can be chosen according to design wind loads and the control effectiveness can be over 30% with the chosen frictional force under 0.3 to 2 times of the designed wind loads.

Experimental Research of Uniaxial Compression Bearing Capacity on Large Diameter CFST Columns

This paper focused on the uniaxial ultimate-bearing-capacity of large size concrete filled steel tubular (CFST) columns. Two aspects were investigated experimentally. To verify the feasibility of similarity principles for large size components, a series of uniaxial compressive experiments were conducted using different scaled specimens, the prototype of which is a CFST arch rib in an authentic arch bridge. Meanwhile, two specimens with same scale were tested axially and eccentrically to investigate the difference of bearing capacity resulted from the pierced-column. The experimental results show that the size effect on the bearing capacity of the rib is so insignificant that the scaled specimen can be used to obtain the maximum capacity of the full-scale component. The inserted steel tubes in the middle of the column cause the reduction of its capacity and the reduction factor from axial loading is bigger than that from bias load. Moreover, the eccentricity reduces the effect of piercing on the capacity of CFST column.

A Method for Damage Detection Based on Correlation Characteristic of Acceleration Response

A damage detection method using BP neural network based on a novel damage index, the correlation characteristic of the acceleration response, is proposed, and is evaluated through the FEM simulation and experiment verification. On the basis of achievements in existence, the feasibility of using the correlation characteristic as damage index is validated theoretically. The damage detection for a simple-supported beam using the proposed method was FEM simulated. The results showed that the trained BP neural network can correctly detect the location and extent of damages in both single damage case and multi-damage case. A model test of a reinforced concrete simple-supported beam was performed to verify the validity and efficiency of the damage detection method. From the results of the model test, it is shown that the trained BP neural network can correctly locate the damage mostly detect the extent of damage. A conclusion is given that the novel damage detection method using the correlation characteristic of the acceleration response as damage index is feasible and efficient.

Seismic Damage Causes and Strengthening Methods of Museum Free-Standing Cultural Relics

To protect museum cultural relics, seismic damage causes as well as aseismic strengthening methods of free-standing museum cultural relics were studied in this paper. Museums, cultural relics and their bases were all considered to study causes of damage of free-standing relics. Shortages of typical domestic aseismic methods were discussed, overseas isolation techniques were introduced. Based on 2 typical examples, reasonable strengthening methods for museum cultural relics were further demonstrated. Results show that main damage causes of museum cultural relics under earthquakes relate closely to over strong earthquake intensity, shortage of strengthening measures of relic, destruction of showcase or museum building and so on; museum, showcase and relic are all important factors for aseismic strengthening of the relics. Besides, to effectively protect the relics, traditional strengthening methods have to be improved; development as well as application of new isolation devices is encouraged.