The invention provides a
pipe gallery subarea excavation method capable of guaranteeing half-width passing of an existing road, belongs to the technical field of
geotechnical engineering design and construction, is applied to underneath passing of existing road nodes of a comprehensive
pipe gallery, and can guarantee the half-width road passing requirement during construction of a foundation pit of the
pipe gallery. The method comprises the steps of firstly, dividing a construction area into a first excavated area and a later excavated area by a middle partition wall; then excavating the firstexcavated area and constructing a support, and allowing vehicles to pass through the later excavated area at the moment; excavating the first excavated area to the bottom of the pit, constructing a pipe gallery structure, and constructing a plain concrete force
transmission belt; then constructing a pipe gallery top plate in the first excavated area, arranging a
retaining wall, covering soil behind the wall body, compacting, and carrying out pavement construction; then turning over to the first excavated area for vehicle passing, excavating the later excavated area, and constructing a support; then excavating the later excavated area to the bottom of the pit, constructing a pipe gallery structure, chiseling off a plain concrete force
transmission belt and butting with a constructed structure; finally, after the integral strength of the pipe gallery structure is formed, constructing
road surface soil covering and being open to traffic for completing construction.