On June 8, Chongqing University (CQU) announced that it had completed hundreds of seismic tests on a six-story cold-formed steel-framed building. The building that experienced horizontal-vertical earthquakes of magnitude 8 still did not collapse. This marked that CQU has built the world's first full-scale cold-formed thin-walled steel-framed building with the largest model size and the highest seismic resistance.

This experimental project comes from the national key research and development program–Research and Demonstration Application of High-performance Steel Structure System, and the major project of National Natural Science Foundation of China–Research on High-Efficient Seismic System of Steel Structure, which is led by Prof. Zhou Xuhong and Prof. Shi Yu, academicians of the Chinese Academy of Engineering from CQU. The success of the testing will promote the development and application of cold-formed thin-walled steel structures in multi-story buildings in China.

"In 2006, we had built a three-story cold-formed, thin-walled steel-framed building," Prof. Zhou said, adding that such buildings, however, are not enough for the general public, as China's large population and small per capita floor space require higher buildings with prefabricated steel structures, thus demanding higher seismic and fireproof performance.

How can the building withstand a magnitude-8 earthquake? The secret lies in the black and silver shear walls.

"Shear wall, also known as the windproof wall, aseismic wall or structural wall, is the main wall in a building to resist wind forces or seismic actions, so as to prevent the structure from shear damage," said Prof. Shi. Shear walls in traditional buildings are usually made of reinforced concrete.

It is the lateral load resistance system with dual protective effects, guaranteed by the system of two new types of horizontal-vertical shear walls, that enables the building to withstand a horizontal-vertical earthquake of magnitude 8.

"Seismic tests have been carried out on steel structures both at home and abroad, but previously the experimental full-scale model in China only had three floors," said Prof. Zhou. He introduced that although American scientists have also conducted vibration tests on six-story steel-framed buildings,.333333333 it was under one-way earthquake condition. Therefore, what CQU completed was the world's first six-story full-scale and horizontal-vertical seismic wave shaking table test, and the structure can respond to more complex real earthquake conditions.

Next, Prof. Zhou's team plans to increase the floor of the model to 15-18 floors, and will also challenge the higher earthquake scale. In addition, Prof. Zhou also envisaged adding intelligence to the building. The heavy work of bolting, for example, can be done by robots. At the same time, solar and wind energy will be integrated as part of the building in the future, which can be stored during the day and used for illumination at night.