Abstract
Abstract Concentrated loads in slabs without transverse reinforcement, usual in highway bridges, result in the horizontal spreading of the shear force towards the supports, situation in which not all the slab width contributes in the shear strength. Based on this, the analytical models of shear strength and punching capacity in slabs may not be suitable to deal with this loading. Since this topic is not widely discussed in the national technical literature, the paper aims to present contributions to these analyses with a focus on the accuracy level of the shear strength analytical models recommended by ABNT NBR 6118:2014. Therefore, the models available in the Brazilian code were applied to an experimental database with 118 test results and the results obtained by the Brazilian and European codes were compared. The results demonstrated that, as presented in the Brazilian code, shear strength model in one-way slabs can lead to unsafe resistance predictions while the punching capacity model can lead to very conservative predictions. From the analysis, it is concluded that considering the reduction of the shear force, in the case of loads distributed in small areas close to the support in slabs, and the use of more suitable procedures to define the effective width, it is possible to improve the level of accuracy of relations between experimental and theoretical values, but this still leads to high percentages of unsafe predictions of resistance (> 40%).
Highlights
The shear strength in reinforced concrete elements without transverse reinforcement is usually analyzed under two approaches: (i) one-way shear and (ii) two-way shear (Figure 1a)
The results demonstrated that, as presented in the Brazilian code, shear strength model in one-way slabs can lead to unsafe resistance predictions while the punching capacity model can lead to very conservative predictions
It is concluded that considering the reduction of the shear force, in the case of loads distributed in small areas close to the support in slabs, and the use of more suitable procedures to define the effective width, it is possible to improve the level of accuracy of relations between experimental and theoretical values, but this still leads to high percentages of unsafe predictions of resistance (> 40%)
Summary
The shear strength in reinforced concrete elements without transverse reinforcement is usually analyzed under two approaches: (i) one-way shear (beam shear) and (ii) two-way shear (punching capacity) (Figure 1a). The development of analytical models that attempt to provide more accurate predictions of shear strength, by means of a consistent theoretical background and accessible application in the design practice, still stand out In this way, the paper aims to present an evaluation of the Brazilian standard with regard to possible approaches for this type of request, in reinforced concrete slabs without transversal reinforcement, and to discuss aspects related to other codes that can be implemented in the Brazilian code in order to make it more consistent for this type of problem. The calculation models provided for the ABNT NBR 6118:2014 [11] were assessed on two approaches: (i) one-way shear strength and (ii) punching capacity
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
