scholarly journals ELASTIC BEHAVIOR OF HARDENED CEMENT PASTE BY USING BACKSCATTER ELECTRON IMAGE AND ELEMENT IMAGE USING ENERGY-DISPERSIVE X-RAY ANALYSIS

2006 ◽  
Vol 71 (603) ◽  
pp. 9-15 ◽  
Author(s):  
Kiyofumi KURUMISAWA ◽  
Toyoharu NAWA ◽  
Keyword(s):  
Cement Paste ◽  
Energy Dispersive ◽  
Backscatter Electron Image ◽  
Elastic Behavior ◽  
Hardened Cement ◽  
Backscatter Electron ◽  
Hardened Cement Paste ◽  
X Ray ◽  
Electron Image

Density mapping of hardened cement paste using ptychographic X-ray computed tomography

2013 ◽  
Vol 36 ◽  
pp. 71-77 ◽  
Author(s):  
Pavel Trtik ◽  
Ana Diaz ◽  
Manuel Guizar-Sicairos ◽  
Andreas Menzel ◽  
Oliver Bunk
Keyword(s):  
Computed Tomography ◽  
Cement Paste ◽  
Hardened Cement ◽  
Hardened Cement Paste ◽  
X Ray ◽  
Density Mapping ◽  
X Ray Computed

scholarly journals Modifying admixtures to cement compositions produced from local raw materials

2018 ◽  
Vol 143 ◽  
pp. 02006
Author(s):  
Daria Vasileva ◽  
Egor Protodiakonov ◽  
Anastasia Egorova ◽  
Svetlana Antsupova
Keyword(s):  
Cement Paste ◽  
Raw Materials ◽  
Mineralogical Composition ◽  
Raw Material ◽  
Free Calcium ◽  
Hardened Cement ◽  
X Ray Diffraction ◽  
Hardened Cement Paste ◽  
X Ray ◽  
Insoluble Compounds

Durability of hardened cement paste depends on chemical and mineralogical composition of Portland cement. The main factor for hardened cement paste is higher content of calcium aluminate and free calcium hydroxide, binding of which into water-insoluble compounds causes increase in resistance to water, frost and corrosion. The purpose of this research is to develop modifying admixtures to cement compositions based on local raw material - rock sand. Chemical and mineralogical properties of the source materials were studied using X-ray spectroscopy and X-ray diffraction analysis. Standard methods were used for defining physico-mechanical properties of sand and binder. Influence of the degree of mechanochemical activation of modifying admixture on the properties of binder and hardened cement paste made on its basis was studied. Research methods of scanning electron microscopy and spectral measurements were applied. The possibility of using admixture based on rock sand as a modifier was determined, its usage providing increase of strength, sulphate and frost resistance, which causes higher durability of cement concrete.

scholarly journals Effects of chloride ions on carbonation rate of hardened cement paste by X-ray CT techniques

2016 ◽  
Vol 122 ◽  
pp. 619-627 ◽  
Author(s):  
Jun-zhe Liu ◽  
Ming-fang Ba ◽  
Yin-gang Du ◽  
Zhi-min He ◽  
Jian-bin Chen
Keyword(s):  
Cement Paste ◽  
Chloride Ions ◽  
Hardened Cement ◽  
Hardened Cement Paste ◽  
X Ray

scholarly journals Effect of Ultrafine Additives on the Morphology of Cement Hydration Products

Crystals ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1002
Author(s):  
Grigory Yakovlev ◽  
Rostislav Drochytka ◽  
Gintautas Skripkiunas ◽  
Larisa Urkhanova ◽  
Irina Polyanskikh ◽  
...  
Keyword(s):  
Silica Fume ◽  
Cement Paste ◽  
Cement Hydration ◽  
Chemical Reactivity ◽  
Xrd Analysis ◽  
Hardened Cement ◽  
Hydration Products ◽  
Hardened Cement Paste ◽  
X Ray ◽  
Strong Adhesion

The present research is focused on the investigation of the influence of ultrafine additives on the structure formation of hardened cement paste and the establishment of the mechanisms of the morphological transformations, which determine the properties of hydrated products. In the course of the research, the modification of ordinary Portland cement was performed by the suspension of multi-walled carbon nanotubes (MWCNTs), carbon black (CB) paste, and silica fume (SF). Scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) microanalysis, X-ray diffraction (XRD) analysis, thermal analysis, and Fourier-transform infrared (FTIR) spectroscopy were used to study cement hydration products. The morphology of hardened cement paste depends on the chemical reactivity of additives, their geometry, and their genesis. The action mechanism of the inert carbon-based additives and pozzolanic silica fume were considered. The cement hydration products formed in the process of modification by both types of ultrafine additives are described. In the case of the modification of cement paste by inert MWCNTs and CB paste, the formation of cement hydration products on their surface without strong adhesion was observed, whereas in the case of the addition of SF separately and together with MWCNTs, the strong adhesion of additives and cement hydration products was noted.

Sign in / Sign up

Export Citation Format

Share Document