Mechanical performance of geopolymer pre-stressed railway sleepers

Abstract

This study is confined to polymerization and the base chemical used is sodium hydroxide 14 molarity and sodium silicate. High Performance Geopolymer Concrete (HPGC) was developed from Alkaline Activator Solutions (AAS) under combination 60% Ground Granulated Blast Furnace Slag (GGBS) and 40% Fly ash (FA) as binder materials produced high compressive strength of 76 N/mm2. Another mixing was made with the same proportion of binder material and filler materials M sand was replaced by Copper Slag (CS). According to the test results the substitution of 50% copper slag with M sand produced at high compressive strength of 80 N/mm2. Geopolymer Concrete was used for the casting of Wide Gauge Prestressed Concrete (PSC) sleepers as per Indian Railway standard specifications. And Pre-tensioning wires of standard High Tensile Strength wire (HTS) were used with a pre-tensioning force of 50kN. Needed Compaction was carried out using table vibrators and steam curing was adopted based on the standard production process of Indian Railways. Under power testing process the hardened concrete sleepers were tested in the laboratory by stimulating the real load transfer condensing the field called Rail Seat Centre Bottom (RSCB), Moment of Resistance (MR) and Moment of Failure (MF). As per the standard static flexural test procedure, the number of sleeper on each side of the sleeper for a load up to 230 kN (MR) and 370 kN (MF) was determined. The result of the tests reveals that the Geopolymer concrete sleeper has a high efficiency load and a high ultimate load.