The invention belongs to the technical field of
engineering measurement, and relates to an
immersed tube joint floating state calibration method. The floating state calibration method comprises the steps that a
pipe joint coordinate system is established in a
dry dock area, at least three non-collinear
pipe top middle section feature points are arranged on the middle section of the top face of a
pipe joint, and three-dimensional coordinates of the non-collinear pipe top middle section feature points in the pipe
joint coordinate system are calibrated; the pipe joint is moved to an outfitting area, the head end and the
tail end of the top face of the pipe joint are each provided with a measuring
tower,
tower top feature points are arranged, the spatial distances between the three pipe top middle section feature points and the two
tower top feature points are measured, the three-dimensional coordinates of the three pipe top middle section feature points in a pipe
joint coordinate system are combined, calculation is carried out through a spatial distance intersection method, and the three-dimensional coordinates of the three pipe top middle section feature points in the pipe joint coordinate
system are calculated. And three-dimensional coordinates of the two tower top feature points in the pipe joint coordinate
system are obtained. The method is easy to operate, calibration of the tower top feature points of the measuring tower can be completed only through
distance measurement, the problem that the floating state calibration precision is poor due to the fact that an existing pipe joint calibration method is affected by posture changes when the pipe joint floats is solved, and the measurement calibration cost and difficulty are reduced.