Abstract:

In order to ensure the construction safety of loess tunnel, rapid ring closure of primary support structure and the construction quality of inverted arch and filling, long trestle for inverted arch is used according to nonblasting excavation of loess tunnel. The formwork erection time is reduced and the inverted arch concrete compacting quality is improved by setting inverted arch formwork and concrete vibrator on long trestle. By adopting the abovementioned technologies, the tunnel excavation, primary support, inverted arch excavation and secondary lining have been carried out in order, the construction efficiency and economic and social benefits have been improved.

Key words: loess tunnel, inverted arch, long trestle, primary support, concrete