Rotary hinges are temporary joints connecting arch ribs with the abutments of rigid frame arch bridges during the vertically downward rotating construction process.

According to the construction experiences of Eastern part skip Shaft construction technique of dahongshan copper mine,introduced the quickly construction technique of thousand meters shaft,analyzed and valued the construction methods,machines collocation,personal organization and construction organization.

This article introduced that our company put up project optimization of construction silo of Guangzhou third underground railway according to request of inviting public bidding document, and combining characteristic and advantage of construction in coal industry, accumulated experience for our company underground railway bidding.

Through the discussion about the method of two-time construction for the retained vertical construction joint of independent column base of cast-in-site reinforced concrete under the specified conditions,this article analyzes the retaining principle,the construction method and the load transfer mechanism of the embedded section steel,and summarizes the experiences of practical projects.