Markov Chain-Based Stochastic Modeling of Chloride Ion Transport in Concrete Bridges

Abstract

Over the last decade, there has been an increasing interest in models for the evaluation and prediction of the condition of bridges in Canada due to their large number in an advanced state of deterioration. The models are used to develop optimal maintenance and replacement strategies to extend service life and optimally allocate financial and technical resources. The main process of deterioration of concrete bridges in Canada is corrosion of the reinforcing steel due to the widespread use of de-icing salts. In this article, numerical models of the diffusion process and chemical reactions of chloride ions in concrete are used to estimate the time to initiation of corrosion and for the progression of corrosion. The analyses are performed for a range of typical concrete properties, exposure and climatic conditions. The results from these simulations are used to develop parametric surrogate Markov chain models of increasing states of deterioration. The surrogate models are more efficient than physical models for the portfolio analysis of a large number of structures. The procedure provides an alternative to Markov models derived from condition ratings when historical inspection data is limited.

A Prognostic Model for Newly Operated Highway Bridges Based on Censored Data and Survival Analysis

“…It assumes that the future state of the bridge only depends on the current state, and the state at each time point can be transferred to another state by a fixed transfer probability, and the transfer probability is expressed as a matrix. How to estimate the transfer probability matrix is the key problem in constructing Markov models [8]. Fang proposed a semi-Markov process model based on the Weibull distribution for degradation prediction of urban bridges, using the Weibull distribution to characterize the degradation behavior of bridges within each condition level and the semi-Markov process to evaluate the transfer probability of bridge degradation processes between adjacent condition levels [9].…”

Compensation Factors for Bridges Built With a Reinforced Concrete Strength Below Its Nominal Value and Located on Seismic Hazard Zones

“…Several physical models to assess the bridge deterioration due to corrosion have been available. One of the simplest models to predict the ingress of chloride ions in concrete are based on the diffusion equation (Crank, 1975;Crank and Gupta, 1975), while more advanced and recent methods use Markov Chains to model ion transport mechanisms in concrete bridges (Zhang et al, 2018). The corrosion deterioration of concrete bridges has received some attention to propose preventive maintenance strategies for groups of bridges (Thoft-Christensen, 2003) and to estimate the service life of concrete infrastructure (Pacheco-Torgal et al, 2018).…”

“…A Markov chain procedure has been proposed to assess the bridge service life based on the chloride ion transport on reinforce concrete bridges in Canada (Zhang et al, 2018). And the life-cycle reliability of reinforced concrete bridges was studied under multiple hazards (Yanweerasak et al, 2018).…”