Comparison of The Compressive Strength and The Microstructure of Metakaolin Metastar and Metakaolin Bangka as Additive in Ordinary Portland Cement

Abstract

Various This paper presents the results of the investigation on the use of Metakaolin (Al2Si2O2) as a supplementary cementing materials to improve the strength of cement. The most effective way to increase the strength of cement is the substitution of a proportion of cement with supplementary cementing materials. One of them was Metakaolin. Metakaolin was produced by thermal treatment calcination from Kaolin at 600-800 Celcius and has highest alumina and silicate purity. By added Metakaolin to Portland Cement type I (OPC), the amount of Calcium Silicate Hydrate (CSH) will increase through binding with Calcium Hydroxide (CaOH). There were two kinds of Metakaolin used in this investigation, commercial metakaolin named Metakaolin Metastar compared with Metakaolin Bangka which derived from Indonesia local resources, Bangka Island. Four Metakaolin replacement levels were employed in this investigation: 5%, 0%, 15%, and 20% with water per cement ratio 0.35, 0.40, and 0.50 both of Metakaolin Metastar and Metakaolin Bangka. The cement pastes cured at room temperature for 7, 14, and 28 days. The mechanical strength examined by compressive strength test, the microstructure were examined by SEM-EDS. The results of the study revealed both Metakaolin Metastar and Metakaolin Bangka enhanced the compressive strength of OPC. The most appropriate strength was obtained for a substitution of 20% metakaolin metastar which had 46,15% higher than OPC and 5% metakaolin Bangka which had 39,06% higher than OPC. The hydration rate was examined by Thermal Analysis Monitor. The results indicated that metakaolin metastar released higher heat than metakaolin Bangka. It can be concluded that Metakaolin metastar was more effective than metakaolin Bangka as additive in OPC.

Utilization of silica-enriched filter cake industry by-products as partial ordinary portland cement replacement

“…Post-treated filter cake (MK) also contains alumina which produced additional alumina-containing phases some of which are crystalline as explained in a previous study [44]. 3CaO.SiO2 & 2CaO.SiO2 phases in clinker are reacted with moisture (H 2 O), and produced Calcium Silicate Hydrates (CSH) and Ca(OH) 2 .…”

“…According to a prior study, MK was employed as a partial substitute for cement. It reacts with calcium hydroxide to form additional calcium silicate hydrate, which strengthens the mortar structure [44]. Apart from calcium silicate hydrates, calcium hydroxide (CH) and calcium aluminosilicate hydrates (CASH) are the main hydration products of OPC-cement pastes with and without 10% MK.…”

Intelligent Design of Building Materials: Development of an AI-Based Method for Cement-Slag Concrete Design

“…It is one of the most important properties of concrete. The relationship between the UCS of concrete and the proportion of the admixture is non-linear, so it cannot be simply calculated by a mathematical formula [ 36 , 37 ]. Many researchers have proposed the use of machine learning to achieve more efficient optimization of the UCS of concrete [ 10 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 ].…”