After the installation @1500W Building of the floor supports and their tensioning (Fig.1), carried out for the future placement of the scientific equipments in the SQZ-R&D Lab, we made a check survey of the reference points located inside the SQZ-R&D Lab, in order to exclude any unwanted displacement.
The check has been carried out measuring, before and after the stiffening of the floor, the same reference points located inside and outside the Lab (Fig.2, 3 and 4) and surveyed by the same single station of AT403 laser tracker.
The first survey considered was that of framing the reference points in the VRS network, reported in eLog58222, while the second survey has been carried out last Wed, Jan 11.
Then, the difference of the Z coordinate between each reference point has been calculated, and the result is shown in Tab.1.
As reported, between the initial survey (Staz07) and after the installation of the structural reinforcements (Staz08), the differences of the deltaZs for each point located inside the Lab (1500W-06, 1500W-07 and 1500W-08) result less than 0.4 mm, thus within the accuracy of this kind of survey. Moreover, the differences are of the same order also for the all other points outside of the intervention area, therefore within the expected accuracy.
As conclusion, it can be stated that no raising of the height of the floor has been measured due to the floor stiffening.