Geopolymer concrete production by utilizing unprocessed pond ash as fine aggregate and ground pond ash as binder

Most of the coal ash produced by thermal power plants is unused and often dumped into the ash ponds. This part of coal ash is generally termed as Pond Ash (PA). In this study, PA collected from storage ponds/lagoons near thermal power plants was termed as Unprocessed Pond Ash (UPA). In the first phase, Geo Polymer Concrete (GPC) was produced using UPA as a fine aggregate replacement for Crushed Stone Sand (CSS) up to 100% at an increment of 20%. Fly ash (FA) was used as a binder along with Ground Granulated Blast furnace Slag (GGBS) as calcium promoter at a ratio of 70:30. Later, UPA is mechanically activated by grinding in an Industrial hammer mill and this activated PA was termed as Ground Pond Ash (GPA). In second phase, GPC was produced by using UPA as complete fine aggregate and GPA as binder replacement to FA up to 100% at an increment of 20%. Compressive strength, RCPT, Acid attack and FTIR tests were conducted on GPC. Strength, microstructural and durability studies confirmed that moderate grade GPC (About 40 MPa) can be produced with UPA as complete fine aggregate and GPA as binder, where 37% of the total quantity of material of GPC is derived from PA.