Development of a Pre-Evaluation and Health Monitoring System for FAST Cable-Net Structure

The Five-hundred-meter Aperture Spherical radio Telescope (FAST) is one of China’s major pieces of national infrastructure. A variable cable-net structure is used as the main supporting structure of the active reflector. The displacement of the cable net works through actuators. The realization of linkage control is a multi-degree-of-freedom and complex coupling control system. Due to factors such as the temperature difference between day and night, as well as actuator failure, the reflector control accuracy and even structural safety are affected during the position-control process of the cable net, so realizing evaluation of control accuracy and fault warning of the reflector is a significant problem. This paper proposes a pre-evaluation and health monitoring system based on advanced mechanical simulation technology. Through this system, on-site staff can expeditiously analyze the model to determine whether the cable net is currently in a safe state, predict the fatigue degree of the components, and maintain the structure when appropriate. The pre-evaluation and health monitoring system adequately ensure the stable functioning of the FAST cable net, improve the efficiency of on-site maintenance work, and markedly reduce the safety risk of the structure.

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Intelligent Health Monitoring System for a Railway Cable-Stayed Bridge

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.148-149.1390 ◽

2010 ◽

Vol 148-149 ◽

pp. 1390-1393

Author(s):

De Shan Shan ◽

Peng Yan ◽

Zhen Hua Wang

Keyword(s):

Information Processing ◽

Monitoring System ◽

Health Monitoring ◽

Signal Transmission ◽

Structural Safety ◽

Signal Acquisition ◽

Processing Technologies ◽

Health Monitoring System ◽

Cable Stayed Bridge ◽

Long Span

Intelligent health monitoring system of the long-span railway cable-stayed bridge requires the comprehensive knowledge of instrumentation, analytical and information processing technologies with the knowledge and experiences in design, construction, operation and maintenance of railway cable-stayed bridge for long-term monitoring the performance throughout its lifecycle. It is necessary to perform sensor-based structural monitoring for identifying the bridge conditions in order to assure the structural safety and to evaluate the operational performance. The considerations for deploying a proper monitoring system are appropriate sensor instrumentation, robust signal acquisition, reliable signal processing, and intelligent signal and information processing. The experience on developing an autonomous monitoring system in the one certain railway cable-stayed bridge newly constructed is introduced in this paper. Sensor and hardware instrumentation, signal transmission, signal acquisition and analysis are schematically described mainly. Experience through this work will be worthwhile lessons for other similar efforts.

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Structural Health Monitoring System for “Uldolmok” Tidal Current Power Pilot Plant and Its Applications

Volume 4: Ocean Engineering; Ocean Renewable Energy; Ocean Space Utilization, Parts A and B ◽

10.1115/omae2009-80101 ◽

2009 ◽

Cited By ~ 1

Author(s):

Jin-Hak Yi ◽

Kwang-Soo Lee ◽

Jin-Soon Park ◽

Woo-Sun Park

Keyword(s):

Structural Health Monitoring ◽

Sea Level ◽

Monitoring System ◽

Health Monitoring ◽

Pilot Plant ◽

Tidal Current ◽

Structural Safety ◽

Structural Members ◽

Health Monitoring System ◽

Structural Health Monitoring System

In this paper, the structural health monitoring system for “Uldolmok Tidal Current Power Pilot Plant (TCPP)” is briefly introduced and the measured data obtained up to now are analyzed. TCPP is basically constructed in the ocean area with high current speed, and therefore the current loading is governing the structural safety than the wave or wind loadings. Usually the soft soils are eroded due to the current and the soft and hard rocks are composing the seabed in strait which tidal current of high speed. Therefore the coring is not so easy due to rock seabed condition and also the operational time is very limited. And also the structural members should not be over designed with large size of steel pipe not to obstruct the tidal current. Due to the difficulties in coastal construction, relatively severe current loadings, and optimized slender structural members, it is very important to monitor the structural safety of the tidal current power plant in normal operation condition and also in severe storm condition. However, the sensor installation is much more difficult for TCPP structure than conventional in-land structures such as bridges and buildings since the sensors should be fully waterproof and the cables should be able to endure the corrosive condition. In this study, we installed the sensors under the sea level and are going to install the sensors above the sea level in this year after the construction is completed. Now the structure is under construction. The conventional type strain sensors and smart FBG optical sensors were installed in the lower part of the jacket legs to measure the dynamic and static strains and the MFC (Macro Fiber Composite) sensors were also installed at the same location to measure the impedance change due to loading and corrosion conditions.

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