Tuesday, May 9, 2017
Extended Strip Model for Reinforced Concrete Slabs under Concentrated Loads
In the latest issue of the ACI Structural Journal, my collaborators and myself have published a paper titled "Extended Strip Model for Reinforced Concrete Slabs under Concentrated Loads." This paper introduces the plastic design model for reinforced concrete slabs under concentrated loads close to supports that I developed in my PhD thesis (see also this post). Close to my graduation date, I talked to a Canadian colleague who was in touch with the original author of the Bond Model, and we started to exchange ideas on the model shortly afterwards. After a meeting at a conference a year later, and some additional research we fine-tuned some details of the model. Life as a starting faculty member left me with little time to continue working on this project, and only when I received an USFQ Chancellor Grant to finish the paper we started in 2013, I committed fully to finish this research project.
You can find the abstract of the paper her:
Typically, beam shear failure is studied by testing small, heavily reinforced beams subjected to concentrated loads, and punching shear failure by testing slab-column connections. Both cases are related to shear in slender, flexural members. For deep members, strut-and-tie methods provide solutions. One-way slabs subjected to concentrated loads close to supports, as occurs with truck load on slab bridges, are much less studied. A theoretical solution to this problem is found by modifying the Strip Model for punching shear into an Extended Strip Model, taking into account the strut between the load and the support. Moreover, the Extended Strip Model takes into account the reduction in capacity resulting from unfavorable geometric circumstances. The resulting capacities based on the Extended Strip Model and on the shear provisions from NEN-EN 1992-1-1:2005 and ACI 318-14 are compared to experimental results, showing the improvement and uniformity of results by using the Extended Strip Model.