Abstract:

The types, application key points and functions of shapedsteel arch are presented. The key factors, including closely connecting between shapedsteel arch and surrounding rocks, strengthening the support of arch feet, closely connecting between shapedsteel arch and concrete and using highperformance shapedsteel arch, which can improve the supporting effect of shapedsteel arch, are presented. It is emphasized that the wedge should be used at the connection between steel arch and surrounding rocks. The shaped steel can be used under bad surrounding rocks. The author suggests that the Ishaped steel can be replaced by the Hshaped steel under large construction crosssection and bad surrounding rocks without enlarging the construction crosssection and increasing the concreting amount. The retractable steel support used in Gotthard Tunnel in Switzerland can improve the rigidity of the tunnel. The steel arch is installed by labor in China. The steel arch installing machine used in Japan can improve the construction efficiency and guarantee the construction safety. The construction management of steel arch in Japan is presented. The girder is more popular than steel arch in China and abroad. The construction of girder in China is superior to that abroad. The girder used in China has 4 feet and that used in European countries has 3 feet. The reinforcing rib used in Norway is presented in detail. The testing results of highway tunnel in Japan illustrate that the girder with 3 main ribs is superior to the Hshaped steel under the same bearing capacities. The practicability of highperformance concrete in Japan is studied. The author suggests that the application and applicable conditions of girder and shapedsteel arch should be further studied.

Key words: tunnel, mining method, shapedsteel arch, retractable steel support, mechanization, construction management, girder, reinforcing rib, concreting