Structural health monitoring Fugro parking garage

Location: Nootdorp, Netherlands
Start: 01/04/2023
Type: Parking Garage
Companies Involved:

• Fugro

• TotaLite

Project Overview

The parking deck of the parking garage of Fugro Nootdorp shows daily deformation due to the load of the cars of the employees. Fugro wanted to test and prove the accuracy of the TotaLite system in this parking garage. Secondly, Fugro wants to gain insights on the monitoring of parking garages as Fugro foresees parking garages require more monitoring in the near future. 

The challenge

Many parking garages are at the end of their designed lifetime and nowadays need to carry a far higher load than they were ever designed for; due to the growing number of SUV’s and electric cars. These parking garages are often in dense populated areas. Fugro wants to do structural health monitoring to avoid collapsing parking garages.

Our solution

We installed various monitoring prisms on the ceiling measuring deflection of the concrete slab when cars park on the second floor. By having a few targets in a row the deflection shape can be observed. In this setup a single TotaLite monitored 3 cross sections with the furthest on 35 m. For comparison, we installed an automated total station and on 1 cross section 4 tilt meters. The project ran for 6 months.

The results

This project proved that TotaLite can achieve an accuracy of 1,5 mgon which is 1mm accuracy at 40m. It proved that we can monitor the deflection of the cross sections, detect events and the deformation trends like an automated total station. We also concluded that with 1 TotaLite we can monitor the deflection of 3 cross sections which would have required 12 tilt sensors. And we found out at what time the employees of Fugro typically arrive at work and go back home. Both TotaLite and the automated total station show a clear weekly rhythm with a typical displacement of 1 mm during the day. Even public holidays were detected. So it offers an employee monitoring system ;-)