METHOD FOR MEASURING NOXIOUS GAS IN SOIL CLEANING METHOD

摘要

PROBLEM TO BE SOLVED: To continuously advance excavation work to enhance safety by automatically detecting the concentration of combustible gas or oxygen in a real time and to effectively lower the concentration of the combustible gas or oxygen by sending inert gas into a restricted area while reducing the concentration of gas to suppress the diffusion of an offensive smell. SOLUTION: A casing 3 is vertically inserted into the ground by a full revolving jacking excavator 2 equipped with a rotary drive mechanism for chucking the outer periphery of the casing 3 and a drilling bucket 4 or the like is allowed to fall into the casing 3 from the upper end thereof in a suspended state as an excavation means to excavate the ground while discharging soil. In this case, the sensor part 22a of a gas detector 22 is provided to the drilling bucket 4 and the inert gas is drawn into the casing 3 while monitoring the concentration of combustible gas or oxygen by the gas detector 22.