en Structure-Concrete Structure- Concrete Research Paper Research Paper <p align="left"><i><font color="#231f20" face="TimesNewRomanPS-ItalicMT" size="2"><font color="#231f20" face="TimesNewRomanPS-ItalicMT" size="2"><font color="#231f20" face="TimesNewRomanPS-ItalicMT" size="2">Chloride ion ingress in concrete is the main reason of concrete corrosion. In real world both uncertainty and stochasticity are</font></font></font></i></p> <p align="left"><i><font color="#231f20" face="TimesNewRomanPS-ItalicMT" size="2"><font color="#231f20" face="TimesNewRomanPS-ItalicMT" size="2"><font color="#231f20" face="TimesNewRomanPS-ItalicMT" size="2">main attributes of almost all measurements including testing and modeling of chloride content profile in concrete. Regarding</font></font></font></i></p> <p align="left"><i><font color="#231f20" face="TimesNewRomanPS-ItalicMT" size="2"><font color="#231f20" face="TimesNewRomanPS-ItalicMT" size="2"><font color="#231f20" face="TimesNewRomanPS-ItalicMT" size="2">these facts new models should be able to represent at least some of the uncertainties in the predictions. In this paper after</font></font></font></i></p> <p align="left"><i><font color="#231f20" face="TimesNewRomanPS-ItalicMT" size="2"><font color="#231f20" face="TimesNewRomanPS-ItalicMT" size="2"><font color="#231f20" face="TimesNewRomanPS-ItalicMT" size="2">inspiration from classical physics related to diffusion and random walk concepts a stochastic partial differential equation (SPDE)</font></font></font></i></p> <p align="left"><i><font color="#231f20" face="TimesNewRomanPS-ItalicMT" size="2"><font color="#231f20" face="TimesNewRomanPS-ItalicMT" size="2"><font color="#231f20" face="TimesNewRomanPS-ItalicMT" size="2">of diffusion is introduced to show a more realistic modeling/calibration scheme for construction of stochastic chloride content</font></font></font></i></p> <p align="left"><i><font color="#231f20" face="TimesNewRomanPS-ItalicMT" size="2"><font color="#231f20" face="TimesNewRomanPS-ItalicMT" size="2"><font color="#231f20" face="TimesNewRomanPS-ItalicMT" size="2">profile in concrete. Diffusion SPDE provides a consistent quantitative way of relating uncertainty in inputs to uncertainty in</font></font></font></i></p> <p align="left"><i><font color="#231f20" face="TimesNewRomanPS-ItalicMT" size="2"><font color="#231f20" face="TimesNewRomanPS-ItalicMT" size="2"><font color="#231f20" face="TimesNewRomanPS-ItalicMT" size="2">outputs. Although it is possible to run sensitivity analysis to get some statistical results from deterministic models but the nature</font></font></font></i></p> <p align="left"><i><font color="#231f20" face="TimesNewRomanPS-ItalicMT" size="2"><font color="#231f20" face="TimesNewRomanPS-ItalicMT" size="2"><font color="#231f20" face="TimesNewRomanPS-ItalicMT" size="2">of diffusion is inherently stochastic. Brownian motion process (Wiener process) is used in SPDE to simulate the random nature</font></font></font></i></p> <p align="left"><i><font color="#231f20" face="TimesNewRomanPS-ItalicMT" size="2"><font color="#231f20" face="TimesNewRomanPS-ItalicMT" size="2"><font color="#231f20" face="TimesNewRomanPS-ItalicMT" size="2">of the diffusion in heterogeneous media or random fields like concrete. The proposed method can be used to calibrate/model the</font></font></font></i></p> <p align="left"><i><font color="#231f20" face="TimesNewRomanPS-ItalicMT" size="2"><font color="#231f20" face="TimesNewRomanPS-ItalicMT" size="2"><font color="#231f20" face="TimesNewRomanPS-ItalicMT" size="2">chloride ion profile in concrete by only some limited data for a given depth. Then the stochastic chloride ion diffusion can be</font></font></font></i></p> <p align="left"><i><font color="#231f20" face="TimesNewRomanPS-ItalicMT" size="2"><font color="#231f20" face="TimesNewRomanPS-ItalicMT" size="2"><font color="#231f20" face="TimesNewRomanPS-ItalicMT" size="2">simulated by langevin equation. Results of the method are compared with data from some references and all show good</font></font></font></i></p> <p><i><font color="#231f20" face="TimesNewRomanPS-ItalicMT" size="2"><font color="#231f20" face="TimesNewRomanPS-ItalicMT" size="2"><font color="#231f20" face="TimesNewRomanPS-ItalicMT" size="2">agreements.</font></font></font></i></p> Concrete corrosion, Markov process, Stochastic partial differential equation (SPDE), Langevin equation 309 316 http://ijce.iust.ac.ir/browse.php?a_code=A-10-237-3&slc_lang=en&sid=1 A. Tarighat tarighat@srttu.edu 180031947532846009800 180031947532846009800 Yes Assistant Professor, PhD, Civil Engineering Department, Shahid Rajaee Teacher Training University, Shabanlou St., Lavizan, Tehran,Iran