Title: Shear Behavior of Reinforced Concrete Columns with High-Strength Steel and Concrete under Low Axial Load

Author(s): Yu-Chen Ou, Dimas Pramudya Kurniawan and Nuraziz Handika

Publication: Symposium Paper

Volume: 293

Issue:

Appears on pages(s): 1-16

Keywords: Reinforced concrete columns; Cyclic loading; Double curvature; Shear; High strength reinforcement; High-strength concrete.

DOI: 10.14359/51686242

Date: 10/4/2013

Abstract:
The advancement of material technology has led to higher grades of both concrete and steel strengths. High-strength concrete and steel can decrease the size of structural members and increase the available floor area. In addition, it can decrease the consumption of aggregate and steel, promoting environmental sustainability. This research investigates the shear behavior of high-strength reinforced concrete columns under low axial load. The specified compressive strength of concrete is 70 MPa or 100 MPa. The specified yield strengths of longitudinal and transverse reinforcement are 685 MPa and 785 MPa, respectively. Eight large-scale column specimens were constructed and tested in double bending under lateral cyclic load. Test results showed that all specimens had shear failure without yielding of longitudinal reinforcement as expected in design. Higher concrete compressive strength, higher axial load and smaller spacing of transverse reinforcement resulted in higher shear strength. The peak applied load was reached before yielding of transverse reinforcement. The critical shear crack angle was approximately 30° and 20° for columns with 10% and 20% axial load, respectively. The simplified shear strength equation of the ACI 318 code was conservative for columns tested in this research and for high strength columns collected from literature. However, the detailed shear strength equation exhibited non-conservative results for most of the columns examined.