Title:
A Seismic Resilient Concrete Pier System Incorporating Titanium Alloy Bars and Comparison with Conventional Reinforced Concrete
Author(s):
Mahesh Acharya, Jose Duran, and Mustafa Mashal
Publication:
Symposium Paper
Volume:
358
Issue:
Appears on pages(s):
206-229
Keywords:
titanium alloy bars; Ti6Al4V; bridge piers; seismic resiliency; durable bridges
DOI:
10.14359/51740237
Date:
10/1/2023
Abstract:
The use of Titanium Alloy Bars (TiABs) for flexural and transverse reinforcing in new bridge piers located in seismic zones aims to incorporate both durability and seismic resiliency. TiABs offer
advantages such as: higher strength, good ductility, excellent durability, and enhanced fatigue-resistance compared to traditional reinforcing bars. The research focuses on the application of TiABs in construction of new bridges located in seismic and corrosive environments. Application of TiABs in bridge piers increases service life, reduces rebar congestion, yields to lower overstrength factor, and limits residual displacement following an earthquake. An approximately 1/3rd scale bridge pier reinforced with TiABs rebars
and spirals is tested under quasi-static cyclic loading protocol to investigate seismic performance. The performance of the pier was compared against an equivalent pier reinforced with normal steel rebars and spirals. Results from testing suggested enhanced performance of a pier reinforced with TiABs in terms of reducing rebar congestion, ductility, and residual displacement following a seismic event. The structural performance and durability of bridge piers reinforced with TiABs is not compromised in moderate
earthquakes as smaller flexural cracks that are more likely to appear in the plastic hinge zones are not a major concern for this pier.
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