Title:
Performance of Double-Headed Studs under Flexure and Shearing
Author(s):
Aaron Nzambi, Denio Oliveira, and Joao Filho
Publication:
Structural Journal
Volume:
122
Issue:
4
Appears on pages(s):
51-66
Keywords:
anchorage; bauxite; concrete anchoring capacity (CAC); double-headed stud; flexural cracks; pullout strength; punching; shear reinforcement; sustainability; synthetic aggregate
DOI:
10.14359/51745467
Date:
7/1/2025
Abstract:
This experimental study investigates the influence of flexuralcracks and punching shear failure inclination on double-headedstud anchorage within the critical perimeter. The research alsoexplored the technical feasibility of using synthetic coarse aggregatesfrom bauxite residue as a sustainable alternative in structuralconcrete production. The results showed that the overall structuralintegrity is impaired at 40 to 50% due to flexural cracks at thecritical perimeter of 2d (30 degrees); however, the perimeter of1.2d (45 degrees) enhanced the shear reinforcement activationand shear strength up 15%, providing a balanced failure withinthe strengthening zone. Thus, a concrete anchoring capacity (CAC)method was proposed to calculate the contribution of doubleheadedstuds in serviceability and ultimate limit states. In addition,synthetic aggregates performed similarly to natural aggregates,offering environmental benefits such as reducing the carbon footprint and production stages.
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