Vertical accuracy measurement system of reverse hit strut

摘要

PROBLEM TO BE SOLVED: To provide a plumbing error measuring system capable of accurately and easily measuring the perpendicular accuracy of a reversely driven column plumbed in a ground.SOLUTION: This perpendicular accuracy measuring system 1 includes a pipe body 3 attached to the reversely driven column 2, a cover 4, a mark 5, an illumination 6, and a perpendicular collimator 7. The cover 4 is attached to the bottom of the pipe body 3, and the mark 5 is formed on the upper surface of the cover 4. The perpendicular collimator 7 can specify the position of the mark 5.