Experimental Investigation on Element Immersing Process of Immersed Tube Tunnel of Hong Kong-Zhuhai-Macao Bridge

2012 ◽  
Author(s):  
Sheng Peng ◽  
Weiguo Wu ◽  
Keqiang Chen ◽  
Aokui Xiong ◽  
Ziyu Xia
Keyword(s):  
Hong Kong ◽  
High Speed ◽  
Tunnel Construction ◽  
Ministry Of Education ◽  
Scaled Model ◽  
Current Test ◽  
System A ◽  
Sea Bed ◽  
Motion Responses ◽  
Immersed Tunnel

Hong Kong-Zhu hai-Macao Bridge, connecting world famous tri-cities in China, will consists of three different construction elements: a man made peninsula, a world’s longest and widest immersed tunnel and a cross-sea bridge. The key point of this megastructure is the construction of the immersed tube tunnel construction. The accuracy of tunnel element positioning directly determines the quality of tunnel construction. In order to study the behavior of elements during its lowering to the sea bed, the scaled model test has carried out in the Key Laboratory of High-speed Ship Engineering of Ministry of Education, Wuhan, China. Experiment was carried out to investigate the motion responses of the tunnel element in the immersion under wave and current actions and the tensions acting on the controlling cables of its immersing system. A concise description of the model wave-current test is carried out, and the variation of motion responses of the tunnel element and cable tensions against wave, current and immersing depth were obtained, which could be a guidance to the construction of the immersed tunnel of Hong Kong-Zhu hai-Macao Bridge.

Embedded Durability Monitoring System – A Key Part of Ensuring the Service Life of the Hong Kong-Zhuhai-Macao Bridge

2015 ◽  
Vol 738-739 ◽  
pp. 294-298
Author(s):  
Xiang Fang ◽  
Yan Bing Tang ◽  
Long Chen ◽  
Hai Hong Li
Keyword(s):  
Hong Kong ◽  
Service Life ◽  
Real Time ◽  
Monitoring System ◽  
Concrete Durability ◽  
The Real ◽  
System A ◽  
Data Support ◽  
Immersed Tunnel

The Hong Kong-Zhuhai-Macao Bridge (HZMB), is one of the most significant mega projects in China. It is a combination of bridges, artificial islands and an immersed tunnel with a service life of 120 years. Embedded durability monitoring system are used to obtain the real time concrete durability data of the bridge, in order to better understand the durability degradation of the bridge, and to give data support for future durability redesign,. Herein the durability monitoring system used and the selecting of the monitoring points for the HZMB is presented.

scholarly journals Research on predictive sliding mode control strategy for horizontal vibration of ultra-high-speed elevator car system based on adaptive fuzzy

2021 ◽  
Vol 54 (3-4) ◽  
pp. 360-373
Author(s):  
Hong Wang ◽  
Mingqin Zhang ◽  
Ruijun Zhang ◽  
Lixin Liu
Keyword(s):  
Sliding Mode Control ◽  
High Speed ◽  
Sliding Mode ◽  
Mode Switching ◽  
Parameter Uncertainties ◽  
Horizontal Vibration ◽  
Adaptive Fuzzy ◽  
Mode Control ◽  
System A ◽  
Ultra High Speed

In order to effectively suppress horizontal vibration of the ultra-high-speed elevator car system. Firstly, considering the nonlinearity of guide shoe, parameter uncertainties, and uncertain external disturbances of the elevator car system, a more practical active control model for horizontal vibration of the 4-DOF ultra-high-speed elevator car system is constructed and the rationality of the established model is verified by real elevator experiment. Secondly, a predictive sliding mode controller based on adaptive fuzzy (PSMC-AF) is proposed to reduce the horizontal vibration of the car system, the predictive sliding mode control law is achieved by optimizing the predictive sliding mode performance index. Simultaneously, in order to decrease the influence of uncertainty of the car system, a fuzzy logic system (FLS) is designed to approximate the compound uncertain disturbance term (CUDT) on-line. Furthermore, the continuous smooth hyperbolic tangent function (HTF) is introduced into the sliding mode switching term to compensate the fuzzy approximation error. The adaptive laws are designed to estimate the error gain and slope parameter, so as to increase the robustness of the system. Finally, numerical simulations are conducted on some representative guide rail excitations and the results are compared to the existing solution and passive system. The analysis has confirmed the effectiveness and robustness of the proposed control method.

Design of New Dual-Motor Independent Drive System for Electric Vehicle

2012 ◽  
Vol 591-593 ◽  
pp. 251-258
Author(s):  
Wen Wei Wang ◽  
Cheng Lin ◽  
Wan Ke Cao ◽  
Jiao Yang Chen
Keyword(s):  
Electric Vehicle ◽  
Network Architecture ◽  
High Speed ◽  
Simulation Analysis ◽  
Stability Control ◽  
Driving System ◽  
System A ◽  
Important Direction ◽  
Time Predictability ◽  
Information Scheduling

Multi-motor wheel independent driving technology is an important direction of electric vehicle(EV). Based on the analysis of the features of existing independent driving system of electric vehicle, a new dual-motor independent driving system configuration was designed. Complete parameters matching and simulation analysis of the system include motor, reducer, and battery. Distributed control network architecture based on high-speed CAN bus was developed, and information scheduling was optimized and real-time predictability was analyzed based on the rate monotonic (RM) algorithm and jitter margin index. The vehicle lateral stability control was achieved based on coordinated electro-hydraulic active braking. Based on the new dual-motor independent driving system, a new battery electric car was designed and tested. The results show that the vehicle has excellent dynamic and economic performance.

Research on Reconfigurable High-Speed Serial Bus Used in High-Reliability Embedded Computer

2010 ◽  
Vol 20-23 ◽  
pp. 774-778
Author(s):  
Rui Ding ◽  
Yong Qin Hu ◽  
Wei Gong Zhang ◽  
Bo Yang
Keyword(s):  
Computer System ◽  
High Speed ◽  
Communication Protocol ◽  
High Reliability ◽  
Dynamic Reconfiguration ◽  
System A ◽  
Embedded Computer ◽  
Key Points ◽  
Application Scope

The characteristics and limitations of the buses, which are widely used nowadays, are analyzed in this paper. Because these buses don’t adapt to the high-reliability embedded computer system, a novel bus is proposed which is characterized by its high-reliability. And its capacity is reached through its unique datum’s dynamic reconfiguration mechanism. The basic architecture and communication protocol are presented in this paper. And then the key points during realization of this bus are discussed. Finally, the probably application scope and prospects are indicated.

Some Observations of Chaotic Vibration Phenomena in High-Speed Rotordynamics

1991 ◽  
Vol 113 (1) ◽  
pp. 50-57 ◽  
Author(s):  
F. F. Ehrich
Keyword(s):  
Numerical Model ◽  
High Speed ◽  
Chaotic Behavior ◽  
Narrow Region ◽  
System A ◽  
Vibratory Response ◽  
Local Contact ◽  
Jeffcott Rotor ◽  
Subharmonic Response ◽  
Static Part

Subharmonic response in rotordynamics may be encountered when a rotor is operated with its rotational centerline eccentric to that of a close clearance static part, so that local contact can take place during each orbit when the rotor is excited by residual unbalance. The rotor will tend to bounce at or near its fundamental frequency when the rotor is operated at or near a speed which is a whole number [n] times that frequency. Using a simple numerical model of a Jeffcott rotor mounted on a nonlinear spring, it is found that the vibratory response in the transition zone midway between adjacent zones of subharmonic response has all the characteristics of chaotic behavior. The transition from subharmonic to chaotic response has a complex substructure which involves a sequence of bifurcations of the orbit with variations in speed. This class of rotordynamic behavior was confirmed and illustrated by experimental observations of the vibratory response of a high-speed turbomachine, operating at a speed between 8 and 9 times its fundamental rotor frequency when in local contact across a clearance in the support system. A narrow region between zones of 8th order and 9th order subharmonic response was identified where the response had all the characteristics of the chaotic motion identified in the numerical model.

scholarly journals New technologies for high-risk tunnel construction in Guiyang-Guangzhou high-speed railway

2013 ◽  
Vol 21 (4) ◽  
pp. 258-265 ◽  
Author(s):  
Yubao Zhao ◽  
Shougen Chen ◽  
Xinrong Tan ◽  
Ma Hui
Keyword(s):  
High Risk ◽  
High Speed ◽  
New Technologies ◽  
Tunnel Construction ◽  
High Speed Railway
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