Title:
Cellular Automata for Corrosion in Carbon Fiber- Reinforced Polymer-Strengthened Bridge Columns
Author(s):
Jun Wang and Yail J. Kim
Publication:
Structural Journal
Volume:
121
Issue:
1
Appears on pages(s):
5-20
Keywords:
carbon fiber-reinforced polymer (CFRP); cellular automata; column; corrosion; model; rehabilitation; strengthening
DOI:
10.14359/51739181
Date:
1/1/2024
Abstract:
This paper presents the durability modeling of bridge piers
subjected to corrosive environments including atmospheric, splash,
and submerged conditions for a service period of 100 years. Two
types of reinforced concrete columns are used—cast-in-place and
accelerated bridge construction (ABC)—and their time-dependent
performance is predicted by von Neumann’s square lattice in
conjunction with a novel evolutionary mathematics approach
called cellular automata. The capacity of the corrosiondamaged
columns is upgraded using carbon fiber-reinforced
polymer (CFRP) sheets. Depending on the concrete strength and
construction method, chloride migration mechanisms are evaluated
to elucidate the variation of diffusion coefficients, chloride concentrations,
and other corrosion-related issues for those columns with
and without CFRP confinement. For the first 30 years, the chloride
diffusion of the ABC column is slower than that of the cast-inplace
column; otherwise, no difference is noticed. Under the splash
condition incorporating periodic wetting-and-drying cycles, chloride
concentrations remarkably increase relative to other exposure
environments, particularly for the cast-in-place column. The
development of corrosion current density is dominated by the pore
structure of the concrete, and the corrosion initiation of the ABC
column takes 4.3 times longer compared with its cast-in-place counterpart.
At 100 years, the capacity of the cast-in-place and ABC
columns decreases by 28.1% and 23.2%, respectively, primarily
due to the impaired concrete near the degraded reinforcing bars in
a corrosion influence zone. The columns’ responses are enhanced by
CFRP confinement in terms of toughness, energy dissipation, loadcarrying capacity, and load-moment interactions.