Development of magnesium potassium phosphate cement pastes and mortars incorporating fly ash

Download
2018
Bilginer, Baki Aykut
Magnesium potassium phosphate cements (MKPCs) have some promising properties to be considered as an alternative to ordinary Portland cement binders. The favorable properties of these cements are high early and ultimate strength. On the other hand, they have some problems like rapid setting, high heat of reaction, high cost and poor water stability. In this study, the effect of several factors like magnesium-to-phosphate molar ratio (M/P), water-to-binder ratio (W/B) and retarder (borax) content on properties such as setting time, compressive strength and on the microstructural evolution of MKPC pastes is investigated. Also, the effect of sand-to-binder ratio (S/B) and fly ash content on properties of MKPC mortar is investigated. The setting times of the paste samples were found to be between 4 and 10 min. The compressive strengths of the pastes were about 50 MPa. The 28 d compressive strength of the highest-strength mortar, prepared with S/B = 1.25, was almost 80 MPa. This value decreased with increasing fly ash content. Also, the strength loss in water did not seem to change with fly ash replacement. TGA and SEM investigations were also performed on paste samples used to study the effects of M/P and fly ash content.

Suggestions

Production of fly ash-magnesium phosphate cements
Bilginer, Baki Aykut; Erdoğan, Sinan Turhan (null; 2019-05-02)
Magnezyum fosfat çimentolu (özellikle magnezyum potasyum fosfat çimentolu [MKPC]) bağlayıcılar Portland çimentosuna kısmi alternatif olabilecek sistemlerdir. MKPC yaygın olarak kalsine MgO tozu ve potasyum dihidrojen fosfat tuzu kullanılarak hazırlanır. Sulu karışımda meydana gelen asit-baz tepkimesi çok hızlı gerçekleştiğinden, bir geciktirici (boraks) de eklenir. MKPC’nin çabuk priz alma, çok hızlı dayanım kazanma ve yüksek nihai dayanım gibi geleneksel çimentolu sistemlere üstün yan...
Development of magnesium oxalate cements with recycled portland cement paste
İçınsel, Nesim; Erdoğan, Sinan Turhan; Department of Civil Engineering (2020-10-23)
In search of lower-carbon-footprint alternatives to portland cement systems, magnesium-based cements are one of the most promising materials to investigate. Even though it is not possible to directly replace the calcium oxide in portland cement with magnesium oxide, magnesium oxide has its distinct mechanisms of forming binders with various materials. Some of the proven magnesium cements use acid-base reactions to create a binder by coupling an acid with magnesium oxide, such as the well-known magnesium pho...
Effect of mixture proportioning on the strength and mineralogy of magnesium phosphate cements
Bilginer, Baki Aykut; Erdoğan, Sinan Turhan (Elsevier BV, 2021-3)
Magnesium potassium phosphate cement (MKPC) has properties advantageous over ordinary portland cement such as quick setting and rapid strength gain. Although the effect of mixture proportioning on MKPC pastes has been studied, there are conflicting reports on how calcination of magnesia, parameters like magnesium-to-phosphate ratio (M/P) and water-to-binder ratio (W/B), added materials like borax and fly ash, or the addition of sand influence mineralogy and properties like setting and strength. These factor...
Synthesis of alinite cement using soda solid waste
Güneş, Aslı; Yaman, İsmail Özgür; Öztürk, Abdullah; Department of Cement Engineering (2010)
This study is dedicated to give a production route for a kind of low energy cement called alinite cement using the waste material of soda industry as the main raw material. Soda solid waste, clay and minor amount of iron ore were mixed with certain quantities and burned at six different burning temperatures of 1050, 1100, 1150, 1200, 1350, and 1450 ºC. The resultant clinkers were investigated by mineralogical and chemical analysis. Mineralogical analyses were performed by X-Ray Diffraction (XRD) technique. ...
Effects of separate and intergrinding on some properties of portland composite cements
Soyluoğlu, Serdar; Tokyay, Mustafa; Department of Cement Engineering (2009)
In the production of cement, to increase the cement/clinker ratio and decrease CO2 emission, the most important alternative is to produce mineral admixture incorporated cements (CEM II-III-IV-V) instead of portland cement (CEM I). These cements are usually produced by intergrinding the portland cement clinker and the mineral admixtures. However, the difference between grindabilities of the different components of such cements may cause significant effects on the particle size distribution and many other pro...
Citation Formats
B. A. Bilginer, “Development of magnesium potassium phosphate cement pastes and mortars incorporating fly ash,” M.S. - Master of Science, Middle East Technical University, 2018.