Title:
Extended Strip Model for Reinforced Concrete Slabs under Concentrated Loads
Author(s):
Eva O. L. Lantsoght, Cor van der Veen, Ane de Boer, and Scott D. B. Alexander
Publication:
Structural Journal
Volume:
114
Issue:
2
Appears on pages(s):
565-574
Keywords:
bond (concrete to reinforcement); punching shear; reinforced concrete; shear; shear properties; slab; strength
DOI:
10.14359/51689462
Date:
3/1/2017
Abstract:
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 loads 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.
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