1. Draw the center line of the cross on the steel plate. Tie the steel bar, and then determine the center line position. Then install the anchor bolt on the center line, and at the same time set theodolite in the center line direction, preferably two, so that the height of the bolt can be adjusted by the level meter.
2, in order to correct the steel plate, also need to use theodolite to measure, to ensure the accuracy of the steel beam in place. It is best to connect beams and steel columns with bolts to ensure the rigidity reaches the standard, so as not to affect the verticality.