A Study of Punching Shear Capacity of RC Flat Slab Strengthening by Vertical Bolts

Authors

  • Try Phorn Student, Mater of Engineering, Department of Civil Engineering, Faculty of Engineering, Khon Kaen University, Thailand
  • Natthapong Areemit Associate Professor, Department of Civil Engineering, Faculty of Engineering, Khon Kaen University, Thailand

Keywords:

Strengthening, Punching shear, Flat slab

Abstract

This study aims at improving the punching shear capacity of reinforced concrete flat slabs by using post-installed vertical bolts. The focus was made on the case that the compressive strength of concrete was lower than specified, which could represent poor construction that needs remediation. Three full-scale specimens were investigated, i.e. control and two strengthened specimens. One was strengthened by installing vertical bolts in the slab around the column, while the other was strengthened with a greater number of vertical bolts together with steel plates on the top and bottom of the slab. The specimens were loaded monotonically until failure. The results showed that the strengthened samples with vertical bolts had higher punching shear capacity. However, the predicted punching shear capacity considering typical shear reinforcement given by ACI318-19 was significantly underestimated. The addition of steel plates could not only improve the strength of the flat slab but also improve the confinement around the column and thus making it more ductile.

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Published

2024-07-31

Issue

Vol. 24 No. 2 (2024)

Section

บทความวิจัย

License

Copyright (c) 2024 KKU Research Journal (Graduate Studies)

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