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Journal of Marine Science and Technology

2016

Concrete

Articles 1 - 4 of 4

Full-Text Articles in Engineering

Chloride-Binding Isotherms In Concrete Submitted To Non-Steady-State Diffusion-Migration Model, Wen-Hu Tsao, Ming-Te Liang, Ta-Peng Chang Aug 2016

Chloride-Binding Isotherms In Concrete Submitted To Non-Steady-State Diffusion-Migration Model, Wen-Hu Tsao, Ming-Te Liang, Ta-Peng Chang

Journal of Marine Science and Technology

We propose a mathematical non-steady-state, time/depth dependent diffusion-migration model based on the modified Fick’s second law of diffusion. It considers the effects of different chloride binding mechanisms for the transport process of chloride ions diffused in a porous concrete on the variation of its chloride profile. Four different chloride-binding isotherms, i.e., no binding, linear binding, Langmuir binding and Freundlich binding, together with the time/depth dependent chloride diffusivities are investigated. Results of this study show that the variations of amounts of available free chloride ions in the solution of saturated concrete resulting from different chloride-binding isotherms have significant effects on the …


Carbonation Resistance Of Concrete With Mortar Coating, Wen-Hu Tsao, Ming-Te Liang, Nai-Ming Huang, Ke-Hung Liao Apr 2016

Carbonation Resistance Of Concrete With Mortar Coating, Wen-Hu Tsao, Ming-Te Liang, Nai-Ming Huang, Ke-Hung Liao

Journal of Marine Science and Technology

The principal purpose of this paper was theoretically to study the carbonation resistance of a semi-infinite medium which concrete has a mortar coating having diffusion properties different from those of the rest of the medium. The analytical solution of a semi-infinite composite medium was used to predict the time required for subsidence due to concrete with mortar coating. The inaccurate analytical solution was published in previous books. Thus, the analytical solution of a semi-infinite composite medium is re-derived in this article. The governing equations without initial and boundary conditions in the previous books are also pointed out. In order to …


Evaluation Of Penetration Depth And Protective Effectiveness Of Concrete-Penetrating Sealer Materials, Sung-Ching Chen, Ran Huang, Hui-Mi Hsu, Si-Yu Zou, Li-Wei Teng Apr 2016

Evaluation Of Penetration Depth And Protective Effectiveness Of Concrete-Penetrating Sealer Materials, Sung-Ching Chen, Ran Huang, Hui-Mi Hsu, Si-Yu Zou, Li-Wei Teng

Journal of Marine Science and Technology

Crystal penetrating sealer materials (PSMs) are commonly used on the surface of concrete to protect the surface from damage and thereby extend its service life. Such materials penetrate into existing pores or cracks and form crystals, which block potential paths through which unknown materials could enter and degrade the concrete. In this study, the constituent compounds of a PSM were divided into seven categories, labeled CAT I to CAT VII, and five discrete particle size fractions corresponding to sieve Nos. 30, 50, 100, 200, and 200 were considered. Energy dispersive spectrometry revealed that the constituent elements of the PSM were …


Corrosion Of Rebar Under Carbonation And Salt Environment, Wei-Chung Yeih, Jiang-Jhy Chang, Yu-Ping Huang, Ran Huang Apr 2016

Corrosion Of Rebar Under Carbonation And Salt Environment, Wei-Chung Yeih, Jiang-Jhy Chang, Yu-Ping Huang, Ran Huang

Journal of Marine Science and Technology

In this study, the behavior of reinforced concrete under carbonation and in a salt environment was investigated. Three types of cements- Type I cement, Type II cement and highalumina cement (HAC) - were used to study the influence of cement on reinforced concrete behavior. To simulate chloridecontaminated concrete, 1% NaCl (by cement weight) was added to some groups of specimens. Results revealed that the carbonation released chloride ions from Friedel's salt, which increased the chloride content near the carbonation front. The carbonation rate of HAC concrete was higher than that of Type I and Type II cement concrete. The corrosion …