Abstract：
Sequence method foundation pit excavation construction technology was adopted in the tunnel engineering construction under the future road which was above the Zhengzhou city metro line1. The technique applies to the construction of tunnels that above the existing operate metro area, The metro tunnel vertical displacement cumulative values caused by excavating and unloading were reduced by the implementation of sequence method construction technology, and the safety of the underground tunnel structure was ensured. Foundation pit excavation unloading activities were successfully completed above the metro tunnel.
