Durabilitas Beton Geopolimer Berbasis Fly Ash Kalsium Tinggi Dengan Metode Kering Di Lingkungan Klorida

Reinforced concrete is a material that is widely used for building infrastructure in corrosive environments. Ordinary Portland Cement Concrete (OPCC) concrete was chosen because its constituent materials are relatively easy to obtain in addition to its resistance to corrosion. The use of OPCC for infrastructure in corrosive environments so far to meet the standard planned building life provides limitations that must be followed, including the quality of concrete, water cement factor, type of cement used and thickness of the concrete cover. In recent years, an alternative concrete material has been developed, namely Geopolymer Concrete (GC) by utilizing coal combustion residue (fly ash), slag. Previous researchers made BG with the wet method. Previous researchers generally used low-calcium fly ash (type F) because it was easier to implement. This study used high-calcium fly ash (type C) with very fast hardening. This study developed a dry method of GC to overcome the very fast hardening of GC caused by the use of type C fly ash. GC material with type C fly ash as an alternative material for building structures in a chloride environment was tested regarding the characteristics and durability of dry method BG with a BOPC comparison. This study divided 3 test groups, namely GC and OPCC without exposure, GC and OPCC with an exposure time of 60 and 120 days and GC and OPCC with acceleration. Durability observations included pH, porosity, absorption, permeability, resistivity, chloride penetration and diffusion coefficient and corrosion acceleration. The results showed that GC had an average compressive strength of 46.77 MPa, meeting the minimum requirements of 35 MPa for use in a chloride environment. OPCC has an average compressive strength of 64.78 MPa. Tests of porosity, absorption (absorption) and corrosion acceleration showed that GC had better durability than OPCC. Tests of pH, permeability and resistivity showed GC has the same durability as OPCC. Chloride penetration test and diffusion coefficient showed that GC had lower durability than OPCC. The test results show that GC has better durability than OPCC