Last digging Shank time of shielded tunnelling machine position measuring method

摘要

PURPOSE:To easily detect a position in the event of matching underground by transmitting a sound wave from one of two excavators excavating in opposite directions, receiving the sound wave at a plurality of circumferential points of the other excavator, and obtaining opposite positions of two excavators from the difference in the arriving time. CONSTITUTION:A sound wave is transmitted in the ground from a transmitting point (a) of the center of the front of a preceding shield excavator A. After that, the sound wave is received by total three points of wave receiving points bc, b1, b2 of the center of the front of a following shield excavator B and symmetrical positions separated by a radius (d). Then, a relative position of both excavators A and B is obtained based on the speed of sound in the ground, distance L between both excavators A and B, the center line of both excavators A and B, distances lc, l1, l2 between each of the wave receiving points bc, b1, b2 and transmitting point (a) and the arriving time of the sound wave at each of the wave receiving points bc-b2.