Steel Collar Strengthening of a Slab-Column Connection under Eccentric Load
Received: 31 March 2024 | Revised: 20 April 2024 and 22 April 2024 | Accepted: 23 April 2024 | Online: 1 June 2024
Corresponding author: Hanaa Abdulbaset Ali
Abstract
The current study focuses on the punching shear resistance of reinforced concrete flat slabs with steel collars, examining it both experimentally and numerically. Six square flat slab specimens were casted and tested under static load, axial load, and eccentric load. The effects of the steel collars and eccentricity on the load-displacement behavior, ultimate load capacity, cracking load, failure mode, stiffness, failure angle, and ductility, were investigated. The results demonstrated that using steel collars in slab-column connection greatly increases the shear capacity of the slab under eccentric loads and moments. The strengthened slabs' ultimate capacity increased by 34% and 61%, respectively, compared to that of the slabs without collars. ABAQUS simulation results were in good accordance with the experiments. The findings underline the efficiency of the steel collars in increasing the efficiency of slab-column connections with punching shear, which is a cost-effective strengthening technique. This research provides knowledge about slab-column connections and offers relevant indications for the design and strengthening of the construction.
Keywords:
slab-column connection , flat slab, steel collarDownloads
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