Effect of SiO2 Sol/Silane Emulsion in Reducing Water and Chloride Ion Penetration in Concrete

Abstract

Here, a new concrete hydrophobic treatment method is developed using SiO2 sol and silane emulsion. The effectiveness of the modification for concrete protection is evaluated through testing water absorption and chloride diffusion. Two types of concrete with different strength grades (C40, C50) are used as the research object. The results show that the water capillary absorption coefficient and chloride ion diffusion coefficient of concrete decrease greatly under the protection of SiO2 sol and silane emulsion. Additionally, the protection effect is better with the increase of SiO2 consumption. Contact angle test results reveal that when the coating amount of SiO2 sol and silane emulsion is 300 g/m2, respectively, the contact angle reaches 150.2°, indicating the concrete (C40) surface reaches the superhydrophobic state. Through scanning electron microscope (SEM) observation, it is found that the hydrophobic effect of the SiO2 sol/silane emulsion is mainly due to the change in the surface morphology of concrete (C40).

Innovative approach for the protection of recycled concrete by biogenic silica biodeposition

“…These results compare favourably with other studies into waterproofing treatments for concrete. For example, Geng et al [30] treated concreate with combinations of 50.5 % silane emulsion and a Nano-SiO 2 preparation made using the sol-gel process. The silane emulsion (600 g/ m 2 ) alone was found to reduce the water absorption coefficient of concrete by 70 %.…”

“…Thus, diatom distribution throughout the biofilm is heterogeneous, with micro-scale variations [21] dependant on surface roughness and microtopography [23]. In addition, physical, chemical and biological changes in the environment also affect diatom communities causing temporal fluctuations in population numbers and distribution [21].To date, research into protective bio-treatments for concrete has considered the use of bacterial calcium carbonate biodeposition [25][26][27][28] or the direct application of laboratorysynthesised nano-silica [29][30][31][32].…”

Acid Radical Tolerance of Silane Coatings on Calcium Silicate Hydrate Surfaces in Aggressive Environments: The Role of Nitrate/Sulfate Ratio

“…Such coatings can make the concrete resistant to biological inorganic acids and harmful ions. By doing so, the service life of the concrete can be extended, and the infrastructure can remain functional for longer periods of time. − Silane materials have been widely used as hydrophobic coatings on concrete facilities. , To protect the surface of concrete blocks, Li et al created a composite coating made of graphene oxide and isobutyltriethoxysilane (IBTS). Experiments on biofouling in the marine tidal zone revealed that the composite coating gave the concrete surface long-lasting hydrophobicity, limiting the attachment of marine microorganisms and successfully suppressing the development of microbial biofilms.…”

Evaluation of the Uniformity of Protective Coatings on Concrete Structure Surfaces Based on Cluster Analysis

“…Concrete material ratios and microstructures have been optimized. These not only enhance the strength of concrete but also improve the anti-corrosion performance [3]. However, with the development of civil engineering structures towards deep sea and mountainous areas, coupled with the frequent occurrence of global climate extremes, the structured environment has become more complex.…”