Recommendations to assess the shear and punching capacity of one-way slabs under concentrated loads according to the ABNT NBR 6118:2014

Author(s)

Alex Micael Dantas de Sousa ^[1] ; Eva Olivia Leontien Lantsoght ; Daniel de Lima Araújo ^[3] ; Lisiane Pereira Prado ^[4] ; Mounir Khalil El Debs ^[5]

Affiliation

^[1] Universidade de São Paulo - Brasil

^[3] Universidade Federal de Goiás - Brasil

^[4] Universidade Estadual Paulista “Júlio de Mesquita Filho” - Brasil

^[5] Universidade de São Paulo - Brasil

• Document type: Journal article
• Source: Rev. IBRACON Estrut. Mater.; v. 16, n. 3 2023-05-22.

Abstract

Abstract This study describes a set of recommendations to improve the precision of shear and punching shear capacity predictions for one-way slabs under concentrated loads, regardless of the governing failure mechanism, using the ABNT NBR 6118:2014 code provisions. For this purpose, a database of 143 test results was developed, including one-way slabs with different support conditions and loading layouts and that failed by different shear failure mechanisms: one-way shear, punching shear or a mixed mode. The key parameters influencing the load capacity and failure mechanism of these slabs were considered for the proposed recommendations: load position and slab width. Adjustments to the effective shear width definition and shear resisting control perimeter were described. Arching action for loads close to the support was also considered in both one-way shear and punching shear predictions. Considering the whole database and without separation by the failure mechanism, the ratio between tested and predicted resistances with the one-way shear expressions shows an average value of 1.22 and a coefficient of variation of 18.3%. The respective ratio between tested and predicted resistances with the punching shear expressions reached an average ratio of 1.23 with a coefficient of variation of 21.3%. Therefore, the proposed recommendations allow for reaching enhanced levels of precision in assessing the shear and punching shear capacity of one-way slabs under concentrated loads, regardless of the governing failure mechanism of the slabs. (AU)

• FAPESP's process: 19/20092-3 - Calibration of shear strength calculation models to bridge slabs with emphasis on the national designs practice
• Grantee: Mounir Khalil El Debs
• Support Opportunities: Regular Research Grants
• FAPESP's process: 18/21573-2 - Calibration of shear strength calculation models to bridge slabs with emphasis on the national designs practice
• Grantee: Alex Micael Dantas de Sousa
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 21/13916-0 - Strategies development for one-way shear and punching shear resistance analyses in bridge slabs
• Grantee: Alex Micael Dantas de Sousa
• Support Opportunities: Scholarships in Brazil - Post-Doctoral