Deicer Salt Scaling Resistance Research Articles

실리카퓸을 혼합한 교면 포장용 고성능 콘크리트의 단기 및 장기 성능 평가

High performance concrete containing silica fume for use in bridge deck overlay emerged as a viable type of bridge deck overlay that economic advantage in construction. They have gained acceptance in Europe, America and Canada in a relatively short time due to their low cost. In this study, high-performance concretes containing silica fume were tested and evaluated in the laboratory to assess their applicability for use in bridge deck overlay. It was conducted with experiments of mechanical and durability characteristics in compressive strength, flexural strength, chloride permeability, abrasion resistance, repeated freezing and thawing cycles and deicing salt scaling resistance. Laboratory test result describe that high-performance concrete containing silica fume for bridge deck overlay application shows most outstanding capacity.

Effects of Proposed Well-Graded Aggregate Gradations on Frost Durability of Concrete

Abstract More stringent gradation requirements than found in ASTM C 33 are sometimes specified to provide a more well-graded particle size distribution, presumably reducing voids, improving workability, thereby reducing water demand, and requiring less cement. Little information is available regarding the effects of gradation on frost durability. A two-phase study examined the effects of selected aggregate gradations on water demand, selected mechanical properties, and deicer salt scaling resistance. In the first phase, the effects of the “8-to-18” combined aggregate gradation, using crushed stone and natural sand, were examined. In the second phase, the effects of fine aggregate gradation were examined for manufactured sands with different angularities. This study found that water demand and deicer salt scaling were both compromised using the “8-to-18” approach. Little, if any, real difference in water demand and scaling resistance between well-graded and uniformly graded manufactured sands was found, however, angularity did have a significant effect.

Effect Of Curing Conditions OnFreeze-thaw De-icing Salt Resistance OfBlast Furnace Slag Cement Mortars

The freeze-thaw de-icing salt scaling resistance tests were performed on blast furnace slag cement (BFSC) mortars, which were cured in 3% NaCl solution, tap water (with/without plastic bags), demineralised water, CaSO4 saturated solution, Ca(OH)2 saturated solution or NaOH saturated solutions. Additionally, the effect of carbonation on the scaling resistance was studied. The effect of carbonation on the microstructure of the BFSC mortar skin was investigated by optical microscopy. The results showed that de-icing salt scaling resistance of a BFSC mortar is strongly dependent on the occurrence of carbonation during curing regime and to a less extent on the chemical composition of curing water.

Frost Durability of Very High Performance Cement-Based Materials

This paper presents the results of a study on the freeze-thaw durability and deicer salt scaling resistance of particular non-air-entrained very high strength cement-based materials. Variables investigated were the microsilica content (0, 10, and 20% by weight), as replacement of an equal amount of cement, and a different quantity of randomly dispersed steel microfibers (0, 2, 4% by volume). Very little research has been undertaken regarding this subject, and these materials are normally considered to be frost resistant because of their intrinsically low porosity. In addition to standard durability tests, compression and bending experiments have been conducted in order to compare the strength and the global response of both reference and freeze-thaw specimens. Tests confirmed the very good behavior of all compositions considered, even those containing high percentages of microsilica and high volume contents of steel microfibers.

Precision of Tests for Assessment of the Deicer Salt Scaling Resistance of Concrete

Abstract Some aspects of the variability of Test Method for Scaling Resistance of Concrete Surfaces Exposed to Deicing Chemicals (ASTM C 672) measurements are discussed in this paper. The influence of the operator's subjectivity on the visual rating is studied. The relationship between the visual rating and the cumulated mass of scaled-off particles is also analyzed. From a statistical analysis of several hundred different concrete mixtures, the variability of the test method is estimated for various types of concrete considering only the cumulated mass of scaled-off particles. Using the same statistical analysis, the precision of ASTM C 672 is finally compared to that of the Canadian brine immersion test (Precast Concrete Paving Blocks, CAN/CSA A231.2 M85) designed to assess the deicer salt scaling resistance of precast concrete elements.

Deicer salt scaling resistance of steel-fiber-reinforced concrete

This project is part of a global research program aimed at studying the durability of steel-fiber-reinforced concrete exposed to severe winter conditions. It was carried out to determine if the use of steel fibers can have a significant influence on the deicer salt scaling resistance of concrete. Sixteen steel-fiber-reinforced concrete mixtures were investigated. The test variables were the water/binder ratio, the use of silica fume, the type of fiber and the quality of the air-void network. The results of the tests show that the fibers have no apparent influence on the deicer salt scaling resistance of concrete. Furthermore, it has been observed that a very small difference in the minimal freezing temperature could have a great influence on the deicer salt scaling resistance.

Durability of microfiber-reinforced mortars

The frost durability of steel and carbon micro-fiber reinforced mortars was assessed. Tests of freezing and thawing and surface scaling were performed on the mortars. The effect of drying on the frost durability was also studied. The results show that the use of steel and particularly carbon microfibers improve the frost and deicer salt scaling resistance of mortars. The improvement is however in part due to the “air entrainment” properties of the micro-fibers.

Freeze-thaw durability and deicer salt scaling resistance of a 0,25 water-cement ratio concrete

Specimens of 0,25 water-cement ratio concrete with various air void spacing factors were tested for freezethaw durability in accordance with ASTM Standard C 666 (procedure A) and for deicer salt scaling resistance in accordance with ASTM Standard C 672. All specimens were moist cured 14 days. Few specimens showed signs of deterioration after 300 and 800 cycles of freezing and thawing and a critical air void spacing factor of approximately 750 μm was determined. All specimens that underwent scaling tests showed a very good resistance to deicer salts and, even after 150 cycles, a maximum of only 0.6 kg/m 2 of scaled off particles was measured.