PSI - Issue 11

Mario Fagone et al. / Procedia Structural Integrity 11 (2018) 250–257 Author name / Structural Integrity Procedia 00 (2018) 000–000

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Table 5. Maximum load(*) and failure modes of specimens subjected to cyclic tests.

(*) The maximum load Fmax is 90% of the average value referring to monotonic tests, according to the defined load cycles. Specimen Failure mode F max [N] 1T.0.C0.1 Mas-F 2841 1T.0.C0.2 Mas-F 2835 1T.0.C0.3 Mas-F 2858 5. Conclusions An experimental program aimed to the analysis of the mechanical behavior of masonry specimens reinforced with CFRP sheets, subjected to both monotonic and cyclic out of plane actions has been described in this paper. In particular, specimens (masonry beams) representative of the effective part of masonry panels strengthened by CFRP sheets bonded parallel to the bed joints have been considered. The experimental results obtained from monotonic tests showed that the load-deflection diagrams have almost a trilinear shape. First cracks in the specimens occurred at the end of the first linear branch, at a load level of about 33% of the maximum load. At this point, two “bending-type” fractures, involving both bricks and perpend joints, occurred close to the end of the constant bending moment region of the specimens. After P1, the stiffness of the specimens considerably decreased: the ratio between the average slope of the second and of the first branches is about 38%. After P2, a third more scattered branch follows up to the specimen failure; within the third branch of the diagram the load level does not considerably vary. Failure of specimens always occurred because of masonry failure. Cyclic tests showed that the slope of the loading and unloading branches almost coincide with that of monotonic tests for load cycles ranging from 0 to 85% of the first peak load. Within this load level, not significant residual deflections have been recorded and no significant cracks occurred in the specimens. Limited damage occurred for load cycles ranging from 0 to 70% of the maximum monotonic load whilst significant stiffness decrease and residual deflection increase were recorded for load cycles ranging from 0 to 90% of the monotonic maximum load: this indicates a considerably damaging of the specimens within this stage. Similarly to monotonic tests, all the specimens failed because of compressive failure in the masonry substrate. 6. Acknowledgement The Authors gratefully acknowledge the financial support provided by the Italian Department of Civil Protection and ReLUIS (Rete dei Laboratori Universitari di Ingegneria Sismica), 2014– 2016 Grant - Innovative Materials. Moreover, BASF and TERREAL-SANMARCO are gratefully acknowledged for providing material. References Anania, L. et al., 2014. Out of Plane Behavior of Calcareous Masonry Panels Strengthened by CFRP. APCBEE Procedia , 9, pp.401–406. Basilio, I. et al., 2014. Assessment of curved FRP-reinforced masonry prisms: Experiments and modeling. Construction and Building Materials , 51(0), pp.492–505. Borri, A., Castori, G., Corradi, M., 2011. Intrados strengthening of brick masonry arches with composite materials. Composites Part B Engineering , 42(5), pp.1164–1172. Briccoli Bati, S., Fagone, M., 2008. Analisi e caratterizzazione meccanica della modalità di rottura di rinforzi in CFRP su elementi in laterizio. In XVII Convegno Italiano di Meccanica Computazionale . Alghero, pp. 1–4. Briccoli Bati, S., Fagone, M., Ranocchiai, G., 2015. The effects of mortar joints on the efficiency of anchored CFRP sheets reinforcements of brick-masonry. Key Engineering Materials , 624, pp.575–583. Briccoli Bati, S., Fagone, M., Rotunno, T., 2013. Lower Bound Limit Analysis of Masonry Arches with CFRP Reinforcements: A Numerical Method. Journal of Composites for Construction , 17(4), p.366. Briccoli Bati, S., Ranocchiai, G., 1994. A critical review of experimental techniques for brick materials. In Proceedings of the 10th International Brick and Block Masonry Conference, Vols 1-3 . Calgary, pp. 1247–1255.