*2.3. The Software Implemented*

For the processing of data obtained from TLS in line scan mode, a code has been developed in Matlab ®. Starting from the point cloud, the best fitting cubic spline is obtained in the case of unloaded structure. This spline represents the reference line for obtaining the displacement curves.

In the case of static load, the same calculation is performed using the point cloud acquired by TLS during the permanence of the load on the structure. The spline extracted is corrected by imposing compliance with structural constraints. The di fference between the obtained spline and the reference line gives the displacements due to the load.

As for mobile loads, the following operations are performed: (1) the single line scans are obtained by detecting the negative increase of the TLS zenith angle; (2) for each line scan, the average of the first and the last point's timestamps is assumed as line time; (3) the best fitting cubic spline is calculated and corrected by imposing compliance with structural constraints; (4) the position of the mobile load is obtained using the previous and following GPS times with respect to the timestamp. The di fference between the spline obtained for each line and the reference line gives the displacements due to the mobile load in the position obtained by GNSS receiver.

If a FEM analysis is available, a comparison between the displacements obtained by TLS measurements and those expected in the design phase can be performed.

The flowchart of the implemented software is shown in Figure 2.

**Figure 2.** The Flowchart of the implemented software for structural analysis.
