PSI - Issue 44

Michele Angiolilli et al. / Procedia Structural Integrity 44 (2023) 870–877 M. Angiolilli et al./ Structural Integrity Procedia 00 (2022) 000 – 000

877

8

only in the joint panel before yielding of both the beam and column reinforcements under the simulated seismic activity (differently from other tests described in the current literature), both the specimen design strategy and test setup were accurately developed. The optimization of steel reinforcement and member geometry, as well as the understanding of certain physical mechanisms, were supported by numerical simulations. In particular, a three-dimensional model using the smeared crack technique was adopted to simulate crack propagation and fracture in concrete. Despite the differentiation of the test procedure between the experiment and simulations, the model well predicted the experimental shear strength. Definitively, the work highlighted that current code or literature formulations can overestimate the shear strength of joints of existing RC buildings characterized by almost null reinforcement. Acknowledgements The authors gratefully acknowledge the support of the “Tonelli Consulting” company ( Avezzano, Italy) and the technicians E. Ciuffetelli and A. Peditto of the LPMS (University of L’Aquila) for the tests. References ACI 374.1, 2005, American Concrete Institute. Acceptance Criteria for Moment Frames Based on Structural Testing and Comm., Farmington Hills. Asgarpoor, M., Gharavi, A., Epackachi, S., 2021. Investigation of various concrete materials to simulate seismic response of RC structures. Structures (Vol. 29, pp. 1322-1351). Bakir, P. G., Boduroğlu, H. M., 2002. A new design equation for predicting the joint shear strength of monotonically loaded exterior beam-column joints. Engineering structures, 24(8), 1105-1117. Beschi, C., Riva, P., Metelli, G., Meda, A., 2015. HPFRC jacketing of non seismically detailed RC corner joints. J. of Earth. Eng., 19(1), 25-47. Calvi, G. M., Magenes, G., Pampanin, S., 2002. Relevance of beam-column joint damage and collapse in RC frame assessment. Journal of Earthquake Engineering, 6(spec01), 75-100. Di Carlo, F., Meda, A., Rinaldi, Z., 2017. Numerical cyclic behaviour of un-corroded and corroded RC columns reinforced with HPFRC jacket. Composite Structures, 163, 432-443. Earij, A., Alfano, G., Cashell, K., Zhou, X., 2017. Nonlinear three – dimensional finite – element modelling of reinforced – concrete beams: Computational challenges and experimental validation. Engineering Failure Analysis, 82, 92-115. Grande, E., Imbimbo, M., Napoli, A., Nitiffi, R., Realfonzo, R., 2021. A macro-modelling approach for RC beam-column exterior joints: first results on monotonic behaviour. Journal of Building Engineering, 39, 102202. Hakuto, S., Park, R., Tanaka, H., 2000. Seismic load tests on interior and exterior beam-column joints with substandard reinforcing details. Structural Journal, 97(1), 11-25. Hassan, W. M., Moehle, J. P., 2012. Experimental assessment of seismic vulnerability of corner beam-column joints in older concrete buildings. In Proceedings, 15th World Conference on Earthquake Engineering, Lisbon, Portugal (pp. 24-28). Hassan, W. M., Elmorsy, M., 2022. Cyclic nonlinear modeling parameters for unconfined beam-column joints. ACI Structural J., 119(1), 89-104. Hu, H. T., and Schnobrich, W. C., 1990. Nonlinear analysis of cracked reinforced concrete. Structural Journal, 87(2), 199-207. Lima, C., Martinelli, E., Faella, C., 2012a. Capacity models for shear strength of exterior joints in RC frames: state-of-the-art and synoptic examination. Bulletin of Earthquake Engineering, 10(3), 967-983. Lima, C., Martinelli, E., Faella, C., 2012b. Capacity models for shear strength of exterior joints in RC frames: experimental assessment and recalibration. Bulletin of Earthquake Engineering, 10(3), 985-1007. Lima, C., Angiolilli, M., Barbagallo, F., Belletti, B., ... Verderame, G., 2018. Nonlinear modeling approaches for existing reinforced concrete buildings: The case study of De Gasperi-Battaglia school building in Norcia. In Conf. on Italian Concrete Days (pp. 82-95). Springer, Cham. Marino, E. M., Barbagallo, F., Angiolilli, M., Belletti, B., Camata, G., Dellapina, C., ... Verderame, G., 2019. Influence of nonlinear modeling on capacity assessment of RC framed structures, COMPDYN 2019 (pp. 2781-2795). National Technical University of Athens. Masi, A., Santarsiero, G., Nigro, D., 2013. Cyclic tests on external RC beam-column joints: role of seismic design level and axial load value on the ultimate capacity. Journal of Earthquake Engineering, 17(1), 110-136. Murad, Y., Abdel-Jabar, H., Diab, A., Hajar, H. A., 2020. Exterior RC joints subjected to monotonic and cyclic loading. Engineering Computations . Nicoletti, V., Carbonari, S., Gara, F., 2022. Nomograms for the pre-dimensioning of RC beam-column joints according to Eurocode 8. Structures (Vol. 39, pp. 958-973). NTC, Norme tecniche per le costruzioni in zone sismiche, in Italian, Ministerial Decree DM; 2018. Pampanin, S., Magenes, G., Carr, A. J., 2003. Modelling of shear hinge mechanism in poorly detailed RC beam-column joints. 4th FIB Sym. Proc. Ricci, P., De Luca, F., Verderame, G., 2011. 6th April 2009 L’Aquila earthquake, Italy: reinforced concrete building performance. Bulletin of earthquake engineering, 9(1), 285-305. Sarsam, K. F., Phipps, M. E., 1985. The shear design of in situ reinforced concrete beam – column joints subjected to monotonic loading. Magazine of Concrete Research, 37(130), 16-28. Sharma, A., Reddy, G., Vaze, K., Eligehausen, R., 2013. Pushover experiment and analysis of a full scale non-seismically detailed RC structure. Engineering Structures, 46, 218-233. Vollum RL, Newman JB, 1999. The design of external, reinforced concrete beam-column joints. Struct Eng. 77(23 – 24):21 – 27