چكيده به لاتين
Concrete is one of the most used materials in the construction industry. Along with the mechanical properties of concrete, considering its durability is an important issue, especially in humid and corrosive environments. Because of the major breakdowns caused by reinforced concrete structures in abrasion conditions, the surface protection of concrete is a way to reduce the penetration of corrosive materials such as moisture, chlorides, etc. into concrete, and therefore, makes the process of corrosion and deterioration of the structure too slow.
In this research, the effect of the use of amorphous carbon powder in epoxy and mariseal on the properties of mortar and concrete durability was investigated. In the contact angle test for epoxy, it was observed that adding 15% carbon to the epoxy matrix would increase the contact angle by about 60 degrees (from 30 to 90). However, for a hydrophobic material such as mariseal, the use of 20% carbon brings the contact angle from about 150 degrees to 120 degrees.
Volumetric adsorption experiments, surface water absorption rates, as well as water discharges on cement sand mortars with water to cement ratio of 0.3 and 0.45, as well as concrete with a water to cement ratio of 0.4 were conducted. By adding 15% by weight of the carbon powder to epoxy surface protection material, volumetric adsorption of water content in mortars with cement to water ratio of 0.3, about 3 times, and for cements with water to cement ratio of 0.45 about 2 times reduced, which reduces the ability of carbon to reduce water permeability and possibly reduced corrosion rate. The results were also satisfactory at the water absorption rate, and adding carbon would reduce it. In water disposal experiment, carbon powder, lowers the breathing rate of concrete, but the process is so small that it can be ignored.
Finally, it can be said that the use of amorphous carbon powder in surface protection materials because of its hydrophobicity and, consequently, the increased durability of concrete on the one hand, and the consumption of a by-product of chemical plants and contributing to the preservation of the environment on the other hand has a very good justification.
Key words: carbon powder, surface protection, contact angle, permeability, durability
