PSI - Issue 29

Gian Paolo Cimellaro et al. / Procedia Structural Integrity 29 (2020) 142–148 Domaneschi et al. / Structural Integrity Procedia 00 (2019) 000 – 000

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In this work, for sake of simplicity, a ll the dynamic tests will be made by assuming the “polished” side only as contact surface. The previous investiga tion, indeed, showed that the polished surface provides results of the friction coefficient very close to the mean found from the six sides (see Figure 8). Furthermore, such finishing is the most likely to occur in the contact surface of standing sculptures.

0,00 0,10 0,20 0,30 0,40 0,50 0,60 0,70 0,80 0,90 CEMENT MORTAR HYBRID MORTAR LIME MORTAR PLEXIGLASS

mean value of FC

GLASS

TIMBER

STEEL

mean value

diamond sawcut

polished

fine chiselled

rough chiselled

gradined

bush hammered

Figure 8 . Mean values of the friction coefficient found through the static test.

4. Conclusive remarks This paper shows the facility properly set to perform an experimenta l program for the contact behavior of stony materia ls under dynamic excitation. The facility has been developed with reference to the shacking table at the Disaster Resilience Simulation Laboratory at the Politecnico di Torino. Ameasurement procedure has been planned, able to catch the effective acceleration provided at the shaking table and the one at the specimen, and the equipment needed for the facility has been set. A first test has been made on a cylindric concrete sample, and the obta ined results have been showed and rela ted to the adopted dynamic input. This work is a preparatory step of a more genera l research program, a imed at describing the contact behavior of stony materia ls under static and dynamic loading. Acknowledgements The authors acknowledge the generous support of Polithecnic University of Turin and University of Florence, Ita ly. References Aydan O (2020). Dynamic shear tests on rock discontinuities and some considerations. Rock Mechanics for Natural Resources and Infrastructures Development – Fontoura, Rocca & Pavòn Mendoza (Eds) Cimellaro GP, Domaneschi M (2018): Development of Dynamic Laboratory Platform for Earthquake Engineering Courses. Journal of Professional Issues in Engineering Education and Practice, 144(4), 05018015 Garini E, Loli M, Georgiou I. Gazetas G (2018). 3D rocking response of rigid blocks under strong near-fault seismic shaking. XVI European Conference on Earthquake Engineering, Thessaloniki, Greece. Monaco M, Guadagnuolo M, Gesualdo A (2014). The role of friction in the seismic risk mitigation of freestanding art objects. Natural Hazards (2014) 73: 389 – 402. DOI: org/10.1007/s11069-014-1076-9. NTC (2018). Aggiornamento delle «Norme tecniche per le cost ruzioni». G.U. No. 42 del 20 Febbraio D.M. Ministero Infrastrutture e Trasporti 17 gennaio 2018, Roma (in Italian). Pintucchi B, Rotunno T, Tanganelli M, Viti S (2019). Bartolomeo Ammannati’s Fountain: comparisons between different numerical models. RILEM Bookseries – Structural Analysis of Historical Constructions. Aguilar, R., Torrealva, D., Moreira, S., Pando, M., Ramos, L.F. (Eds.) Springer International Publishing, p. 1201-1209. Schmitz TL, Action JE, Ziegert a, John C, Sawyer WG (2005): The difficulty of measuring low friction: uncertainty analysis for frictio n coefficient measurements. J. Trib., 127(3), 673-678 Shih M-H, Sung W-P (2019): Developing Smart Measurement Device to Measure Kinetic Friction Coefficients of Bi-Tilt Isolator. Advances in Civil Engineering, 2019