Sun Valley of Expo Axis applies free-form design idea, which is reticulated shell structure with bolt connection joint.The expo axis is the main entrance and main shaft line of Shanghai world expo 2010 in China, with two floors above ground and half open architecture. The expo axis is one of the five permanent buildings of the expo. It is a large commercial and transportation complex integrating business, catering, entertainment and exhibition services.
Characteristics and Difficulties:
● The steel structure is irregular in space and there are no rules to follow, which makes it difficult to assemble, install and measure the field.
● The structural stability control of large suspension structure during installation.
● A large number of high-altitude welding and induced welding deformation control.
● The single-layer reticulated shell structure requires the joint node to be rigid and flexural connection, and the node connection mode is different to many and different angles. It is necessary to choose a simple and reliable connection form.
The external load of the Expo Axis is mainly the acceleration of the ground motion and the wind pressure on the wind environment and the structure surface. The structural reactions are mainly structural stress, displacement, vibration acceleration, surface temperature, and surface crack development. In view of the characteristics of the long-span structure of the Expo Bridge, the wind pressure on the surface and the surface of the structure is the focus of monitoring the external load of large-span structures. The structural stress monitoring includes the steel surface stress, tensile force, and membrane stress. The structure monitoring system includes a sensor system and a data acquisition system. The data acquisition system also includes a data collector, a relay, a communication host, and a PC system and a module.
The data acquisition system includes a signal transmission device, a signal transmission device, and a signal reception device. The purpose of data acquisition and analysis for monitoring is to determine whether there is damage to the structure and determine the degree of damage.
For the important part of the steel structure in the Sunshine Valley of the Shanghai World Expo Axis, the surface stress of the components was monitored. For the important part of the steel structure in the Sunshine Valley of the Shanghai World Expo, the surface stress of the components was monitored. Long-term on-line monitoring of vibration, wind speed, and wind pressure using a data acquisition system ensures the structural safety of the Expo Axis.
Dynatronic Data Aquisition System can measure an electrical or physical phenomenon such as voltage, current, temperature, pressure, or sound with a computer. A DAQ system consists of sensors, DAQ measurement hardware, and a computer with programmable software. Compared to traditional measurement systems, PC-based DAQ systems exploit the processing power, productivity, display, and connectivity capabilities of industry-standard computers providing a more powerful, flexible, and cost-effective measurement solution.
