Analysis of Chloride Penetration in Concrete with Mineral Admixtures using Neural Network Algorithm and Micro Modelling

신경망 이론과 마이크로 모델링을 통한 혼화재를 사용한 콘크리트의 염화물 침투해석

Kwon, Seung-Jun;Song, Ha-Won;Byun, Keun-Joo;Park, Chan-Kyu
권성준;송하원;변근주;박찬규

  • Published : 20070100

Abstract

Chloride attack is one of the major deteriorations in concrete structures. In order to quantify chloride behavior in concrete, accurate prediction of diffusivity coefficient of chloride ion is necessary. In conventional prediction equations, the apparent diffusivity coefficient is expressed only with the water to cement ratio (W/C), i.e., the detailed mix proportions of concrete are not considered to obtain the diffusivity coefficient of concrete with mineral admixtures. In this study, a numerical technique for chloride penetration in the concrete with mineral admixtures using diffusivity coefficient from neural network algorithm is proposed. In order to obtain the comparable data set considering various mineral admixtures such as ground granulated blast-furnace slag (GGBFS), fly ash (FA) and slica fume (SF), a series of rapid chloride penetration tests are performed and a limited number of diffusivity coefficients are obtained. Total eight neurons (seven material components in trial mixture designs and curing period in submerged condition) are used for neural network. Through the neural network, 120 diffusivity coefficients from 30 mixture designs are obtained and the average of analyzed data is evaluated to be about 7%, which can be statistically acceptable. Finally, an evaluation technique for chloride penetration in the HPC is also developed by utilizing multi component hydration heat model (MCHHM) and micro pore structure formation model (MPSFM) along with obtained diffusivity coefficients from neural network. The applicability of the developed technique is also verified by comparing the simulation results with experimental results as well as other data.

Keywords

References

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