Studies on Portland Slag Cement Made using Blast Furnace and Linz-Donawitz Slag
P. N. Ojha, Abhishek Singh, Brijesh Singh, Subhadra Sen, Ritesh Kumar, and Biswajit M. Patra
Appears on pages(s):
composite slag; durability; granulated blast furnace slag; LD slag; Portland slag
This study aims to investigate the possibility to utilize LD slag as one of the cementitious materials for the preparation of composite slag (having 8% and 15% LD slag) which will subsequently be used for manufacturing Portland slag cement (PSC). PSC samples (having overall 4% to 9% LD slag) were prepared using LD slag from two sources in a laboratory ball mill. PSC samples were analyzed for various chemical characteristics and physical properties. Studies were conducted on concrete mixes prepared at the water-to-cement ratio of 0.65 and 0.40. Fresh, hardened, and durability properties of concrete mixes prepared using PSCs made with composite slag having up to 15% LD slag, were found to be comparable to their corresponding control mixes. Based on the results, it was observed that composite slag having LD slag up to 15% of total slag can be used up to 60% for manufacturing PSC along with clinker and gypsum. The 3-, 7-, and 28-day compressive strength of PSC samples containing LD slags in different proportions, were found to be comparable to control PSC samples and meeting the IS 455:2015 requirements. Even though the free lime content in LD slags was significantly high (free lime content of 3.03% and 3.48%) in comparison to GBFS, it had an almost negligible effect on the PSC prepared using LD slag and soundness of experimental and control PSC was comparable because the maximum amount of LD slag added in overall PSC was restricted to 9%. The addition of LD slag in different proportions up to 9% in overall PSC does not seem to have any detrimental effect on the performance of concrete in terms of sorptivity, carbonation depth, chloride penetration, and diffusion, which indicates its suitability for application in reinforced concrete structures.