# Onsite Testing for Nonlinear Analysis of an Earthquake Damaged Historical Church in Italy
## 3 Onsite Testing and Dynamic Monitoring  
The laboratory of Testing and Research on Structures and Materials (PRiSMa) of the Architecture Department of Roma Tre University received from the Diocesi of Macerata the request to carry out an extensive onsite testing campaign on the church of San Filippo Neri to investigate the structural elements, characterize the mechanical properties of masonry and identify the dynamic behavior of the construction. A total of four double flat jack tests were performed to evaluate the Young's modulus and estimate the compressive strength of masonry. Two tests (M1 and M2) were located at the street level on the exterior walls of the north and south side, one at the ground floor level on the interior masonry in proximity of the southeast pillar (M3) and one at the  
Figure 3: Details of the 2016 earthquake damage: on the right crack above the apse arch, on the left the crack in proximity of the drum. Figure 2: Recurrent longitudinal crack on the dome: on the left the conditions in 1950s, on the right the condition in 2018.  
basement (M4) on one of the main transversal walls of the adjacent Palazzo della Provincia as shown in Figure 4.  
The locations were selected to characterize the structural elements (the pillars) and reduce the invasiveness of the tests (only M3 was performed in the interior but in a concealed area while M4 was performed in the basement, in an area inaccessible to the visitors). The material under testing consists of a masonry prism with an approximated semicircular section, the prism has a height of 500 mm and width of 350 mm as shown in Figure 5. The instrumentation includes two semicircular metal flat jacks and four Penny+Giles SLS130 linear displacement transducers positioned in the points A, B, C and D as illustrated in Figure 6. The transducers and the pressure sensor were connected to a NI SCXI 1313/1520 module and then digitally converted with a NI SCXI-1600 module, parts of NI SCXI 1001 acquisition system. The recording and visualization of the data is realized with a laptop with dedicated LabView software application. The tests followed several loading cycles to optimally evaluate the bearing capacity of masonry. The stress state with the modulus of elasticity was evaluated according to ASTM 1197 standard [12] and the compressive strength according to UNI 1052-1 [13], the results of the tests are reported in Table 1. The [PERSON]'s ratio of test M4 was not evaluated due to a malfunctioning of the horizontal displacement transducers. The flat jack tests reported a significant difference in the modulus of elasticity of the masonry: southern masonry was identified as the stiffer material followed by the northern masonry and eastern masonry; the result was confirmed by unreported consolidation intervention of the exteriors orally communicated by the locals. Figure 4: Double flat jack test locations. Several sonic tests were performed on the southeast pillar of the main hall with the acquisition system Boviar CMS HLF-P series SG02_0128 equipped with piezoelectric hammer. The propagation period of the sonic impulse through the masonry was measured on a mesh of 35 points (12 receivers and 23 transmitters) distance by 25-30 cm along the two opposite sides of the pillar at a height of 158 cm from the floor level; 258 pressure wave trajectories were processed with the dedicated algorithm of the software aTom [14], which returned the sonic tomography shown in Figure 7. \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Test** & **Young Modulus [MPa]** & **Poisson’s Ratio [-]** & **Compressive Strength [MPa]** \\ \hline M1 & 2800 & 0.21 & 3.30 \\ \hline M2 & 4600 & 0.30 & 3.00 \\ \hline M3 & 1800 & 0.26 & 2.80 \\ \hline M4 & 1600 & - & 2.80 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Double flat jack test results. Figure 5: Double flat jack test geometry [mm]. Figure 6: Set-up of the double flat jack test. The video borescope was carried out on of the same portion of masonry encompassing the sonic tomography with the RITEC RII320 LSC video endoscopy.