The invention discloses a construction method of an
air cushion type surge chamber, belongs to the technical field of underground structure construction of
hydropower engineering, and solves the problems of poor high-pressure sealing performance, dynamic response
lag and short structure service life of a traditional surge chamber. Comprising the following steps: releasing guide holes and injecting micro-expansion
slurry to form a pre-supporting arch shell based on
coupling analysis of a three-dimensional geological
radar and a ground
stress field; excavating a cavity by adopting a blasting technology, and spraying a support
coating after blasting; alternately laying a
basalt fiber sealing layer and a
sacrificial metal net
cathode protection layer on the rock wall, and implanting a distributed
optical fiber sensing array; pouring a concrete lining; a
titanium alloy corrugated
air cushion interface film is compounded outside the lining, and
supercritical carbon dioxide is filled;
inert gas is injected stage by stage to establish design air pressure, and
sensing data is linked to regulate and control a cooling
system and
alloy deformation; the dome integrated
scroll compressor unit and the high-pressure gas storage
capsule array achieve 20 ms-level
gas pressure dynamic balance. The
air tightness, the response speed and the long-term operation stability of the surge chamber are improved.