Laboratory Study on Pozzolanic Concrete oriented to Durability Approach of RC Barriers (New Jersey)

Todays, use of concrete barriers has increased due to its advantages over the steel guardrails, including high impact resistance, greater safety and useful service life of about 50 years with minimal repair and maintenance costs. However, in our country, concrete barriers have a shorter service life, and therefore, more costs are imposed annually on highways for the production and replacement of old barriers In most cases, the destruction of concrete barriers is caused by changes in the volume of concrete at an early age. Improper method of execution, such as early opening of the molds, insufficient compaction and lack of wet processing of concrete are the reasons for the spread of damage. Damage caused to concrete barriers includes spalling, surface delamination, horizontal cracks, corrosion, salinization, vertical cracks, surface cracks, and concrete destruction.In this research, after experimental studies on used materials, a suitable mixture design of concrete containing zeolite pozzolan, air entraining additive and superplasticizer with a durability approach has been prepared to increase the service life of New Jersey concrete barriers; In addition to economic justification, it will also prevent the destruction of the environment. In experimental studies, the slump, temperature and air content of fresh concrete, and compressive strength, water penetration depth and resistance to freezing and thawing cycles of hardened concrete have been investigated and their results have been presented. Also, for cores of existing New Jersey concrete barrier, prepared from concrete mixture design containing zeolite, the compressive strength, deterioration of cores of New Jersey exposed to freezing and thawing cycles, and water penetration depth, have been measured.