When there is only one measurable surface at the crack location of the structure and the estimated crack depth is not greater than 500mm, the single-sided flat measurement method can be used.
When conducting horizontal testing, different distance measurements should be taken at the tested location of the crack, and measuring points should be arranged according to whether they span or not (avoiding the influence of steel bars when arranging measuring points).
Calculate the actual propagation distance of ultrasonic waves and the sound velocity of concrete without crossing the joint, read the sound time value of the cross joint flat measurement, and then obtain the crack depth value of each measuring point.
According to the relevant determination method, the depth value of the crack to be measured is finally obtained.
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