Small-clear-distance up-down crossing tunnel construction method

The invention discloses a small-clear-distance up-down crossing tunnel construction method. The small-clear-distance up-down crossing tunnel construction method comprises the steps of preparing for construction, examining a tunnel structure by using a radar, researching a blasting vibration theory, simulating a numerical value of a blasting vibration effect, designing a blasting technique, performing the blasting construction, performing the circular construction and the like. An SIR-3000 geological radar and a 400MHz high-frequency shielding antenna are used for detecting a condition behind a tunnel lining, data is acquired in a continuous sectional recording way, a measurement mark is made every 5 meters, a recording length is 40ns (nanometer per millimicrosecond), and a sampling rate is 512 sample points at every time of scanning. The small-clear-distance up-down crossing tunnel construction method has the beneficial effects that a small-clear-distance crossing tunnel is built on the basis of the existing