Huq, Mohammad S.

Influence of Mechanical Properties of High-Strength Steel on Deformation Capacity of Reinforced Concrete Walls

Abstract eng:
Results are reported from tests of two large-scale reinforced concrete “T-shaped” slender walls under reversed cyclic loading. The specimens are part of a series of four specimens designed to study the effect of reinforcing bar mechanical properties on wall deformation capacity (defined by a drift cycle completed before a 25% loss of strength). Primary variables included reinforcement yield strength and the ratio of tensile-to-yield strength of the reinforcement. An additional aim of the tests is to determine the minimum uniform elongation required of high-strength reinforcing bars for use in earthquake-resistant structures. The walls, 300-in. (762-cm) tall and 10-in. (25.4-cm) thick had a 100-in. (254-cm) long stem joining a 100-in. (254cm) long flange at one end (resulting in a shear span-to-depth ratio of 3). The control specimen had Grade 60 (420) reinforcement with a nominal tensile-to-yield strength ratio of 1.35. The second specimen had Grade 100 (690) reinforcement with a nominal tensile-to-yield strength ratio of 1.25. Future test specimens will have Grade 100 (690) reinforcement with a nominal tensile-to-yield strength ratio of 1.15 and 1.4. The walls were designed so that flexural yielding would limit lateral strength, resulting in an expected web shear stress of approximately 3.5√f’c, psi (0.3√f’c, MPa). Design of the walls complied with applicable ACI 318 Building Code [1] requirements for special structural walls and additional detailing requirements identified in ATC 115 (2014) [2]. A key feature of the design was to limit the neutral axis depth to ensure strain demands approached fracture of the longitudinal reinforcement. The tested walls followed the same loading protocol and experienced bar fracture during the first cycle to a drift ratio of 4%. The similar hysteresis behavior observed from testing of the two walls supports the use of high-strength steel as concrete reinforcement for earthquake-resistant construction.

Contributors:

Ameen, Shahedreen

Conference Title:

Proceedings of the 16th World Conference on Earthquake Engineering

Conference Title:

16th World Conference on Earthquake Engineering

Conference Venue:

Santiago (CL)

Conference Dates:

2017-01-09 / 2017-01-13

Rights:

Text je chráněný podle autorského zákona č. 121/2000 Sb.