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Magnetic Susceptibility Measurements on Fly Ash Admixtured Cement Hydrated with Groundwater and Seawater
American Journal of Materials Science , 2012, DOI: 10.5923/j.materials.20120201.06
Abstract: The present works reports the effect of Flyash on the properties of Portland cement hydrated with ground water and seawater through magnetic susceptibility study. Cement pastes containing 0, 10, 20, 30% replacement of flyash with cement and in a Water cement ratio (W/C) ratio of 0.4 have been prepared. The magnetic susceptibility at different hydration ages has been determined by Faraday Curie balance method and this has been correlated to changes in setting time and compressive strength measurement. The observed result shows that, irrespective of water the magnetic susceptibility increases with increasing flyash percentage replacement level in cement.
The Hydration of Heavy Metal Salts Admixtured High Alumina Cement – A X-Ray Diffraction Study  [cached]
R. Nithya,S. Barathan,M. Gopalakrishan,G. Sivakumar
Applied Physics Research , 2009, DOI: 10.5539/apr.v1n2p19
Abstract: The XRD, Setting time and Compressive strength results of the hydration of High Alumina Cement (HAC) with different concentrations of Cr, Cd, Pb, Zn and Mg as impurities are presented. The heavy metal salts are doped from 100 to 15000ppm in various steps. The hydration products are investigated both qualitatively and quantitatively by X-ray powder diffraction. The initial, final setting time and strength of heavy metal salts doped HAC, which are measured and compared with the phases at different time intervals are discussed. The results show that various concentrations of heavy metal salts doped HAC can play an effective role in conversion reactions (i.e.) from metastable to stable hydrates imparting setting time and strength. It is observed that a lower concentration of industrial waste metal ions do not affect the characteristics of the blend.
A Thermal Analysis Study on Blended Ternary Cement Paste  [cached]
R. Nithya,S. Barathan,D. Govindarajan,K. Raghu
International Journal of Chemistry , 2010, DOI: 10.5539/ijc.v2n1p121
Abstract: Pastes containing High Alumina Cement (HAC) and Ordinary Portland Cement (OPC) were prepared using Ground Water (GW) and 5, 10, 15 and 20%SF. The setting time and compressive strength of these admixtured cement pastes were measured. The hydrated HAC blends were subjected to DTA/TG and DSC analysis. The recorded spectra were compared with the observed mechanical measurements of these blends. The hydration kinetics is well explained through these results. It is evidenced that 10%SF addition is optimum for this blend.
Feasibility Study of Partial Replacement of Cement and Sand in Mortar by Brick Waste Material  [PDF]
Prof. Hemraj Ramdas Kumavat,,Prof. Yogesh Narayan Sonawane
International Journal of Innovative Technology and Exploring Engineering , 2013,
Abstract: Brick waste is investigated for its use as a replacement of cement and sand in cement mortar as it behaves as a pozzoloana. It may make an important contribution towards decreasing the adverse effect of the production, disposal and the dumping of brick waste on the environment. The results show that richer mixes gives lower value of bulk density and higher values of compressive strength for sand replacement with brick waste up to 40%. The paper presents useful data for the brick manufacturing industry, builders and mortar manufacturing companies in terms of minimizing the impact of brick waste and using eco-efficient materials.
Compressive Strength of Jordanian Cement Mortars  [PDF]
Hamadallah Al-Baijat, Maria Chiara Bignozzi, Basem K. Mohd
Open Journal of Civil Engineering (OJCE) , 2013, DOI: 10.4236/ojce.2013.31002
Abstract:

Mortars have been prepared from six cement Jordanian brands and tested for their compressive strengths at 2, 7 and 28 days. The strength has been related to some physical parameters. It has been concluded that the compressive strength and its development with age has some variations between the different cement brands. There is an inverse linear relationship between compressive strength and water absorption, and a weaker positive relation with density. There is no clear relation between consistency and compressive strength. Inverse linear relations exist between less than 63 microns size fraction and strength. To account for the differences in compressive strength at different ages and using different cement brands, it is very important to identify the type and amount of cement mineral phases using concrete petrography and X-ray diffraction and fluorescence techniques.

Performance of Cement for Immobilizing Strontium Waste in Saline Environment  [PDF]
Susetyo Hario Putero, Widya Rosita
Materials Sciences and Applications (MSA) , 2013, DOI: 10.4236/msa.2013.412A002
Abstract:

For solving the radioactive waste storage problem, there is an idea to store immobilized waste at deep sea. Solidifier material, such as cement should be resistance to saline environment for deep sea storage. So, this research objective is to study the performance of cementation method in immobilizing strontium waste in saline environment. Research was conducted by immobilizing strontium waste using Portland pozzolanic cement, white cement and composite Portland cement. Cement, 65 ppm Sr(NO3)2, sand and water were mixed and cast. Strontium waste varied in 2 v/o, 4 v/o, 6 v/o and 8 v/o. After 28 days curing, the cement block’s compressive strength and leaching rate on saline water were analyzed. Determination of compressive strength was

Effect of Incorporating Nanoporous Metal Phosphate Materials on the Compressive Strength of Portland Cement  [PDF]
Dawn M. Wellman,Kent E. Parker,Shas V. Mattigod,Glen E. Fryxell
Advances in Materials Science and Engineering , 2008, DOI: 10.1155/2008/238736
Abstract: Nanoporous metal phosphate (NP-MPO) materials are being developed for removal of contaminant oxyanions (As(OH)O32?, CrO42?, and TcO4?), and cations (mercury, cadmium, and lead) from water and waste streams. Following sequestration, incorporation of metal laden NP-MPOs as a portion of cement formulation would provide an efficient and low-cost way to immobilize metal laden NP-MPOs in an easily handled waste form suitable for permanent disposal. There are no known investigations regarding the incorporation of NP-MPOs in concrete and the effects imparted on the physical and mechanical properties of concrete. Results of this investigation demonstrated that incorporating of NP-MPO materials requires additional water in the concrete formulation which decreases the compressive strength. Thus, incorporation of NP-MPOs in concrete may not serve as an efficient means for long-term disposal.
Study on Modification of Waste Rubber Powder in Cement-Based Composites Mixed with Waste Rubber Powder  [PDF]
Jianmei Zhou
Journal of Materials Science and Chemical Engineering (MSCE) , 2019, DOI: 10.4236/msce.2019.78003
Abstract:
In view of the disadvantage that the mechanical properties of cement-based composites can be significantly reduced by incorporating waste rubber powder in situ, the surface modification methods of the original rubber powder by coupling agent KH560, sodium hydroxide, polyvinyl alcohol (PVA), methyl hydroxyethyl cellulose ether (MHEC) and tetraethyl orthosilicate (TEOS) as precursors were adopted respectively. The modification of waste rubber powder was studied by Change rate of mortar strength of cement-based composite mortar mixed with waste rubber powder. The results show that the hybrid modification method using tetraethyl orthosilicate as precursor has better ef-fect. When 5 phr ethyl orthosilicate is added, the compressive strength and flexural strength of cement-based composite mortar can be increased by 31.7% and 28%. Scanning electron microscopy (SEM) results show that the surface of waste rubber powder with good modification effect has many pro-trusions and flake-like porous structures which are beneficial to its bonding with cement-based materials.
Using cement, lignite fly ash and baghouse filter waste for solidification of chromium electroplating treatment sludge  [PDF]
Wantawin, C.,Chobthiangtham, P.
Songklanakarin Journal of Science and Technology , 2004,
Abstract: The objective of the study is to use baghouse filter waste as a binder mixed with cement and lignite fly ash to solidify sludge from chromium electroplating wastewater treatment. To save cost of solidification, reducing cement in binder and increasing sludge in the cube were focused on. Minimum percent cement in binder of 20 for solidification of chromium sludge was found when controlling lignite fly ash to baghouse filter waste at the ratio of 30:70, sludge to binder ratio of 0.5, water to mixer ratio of 0.3 and curing time of 7 days. Increase of sludge to binder ratio from 0.5 to 0.75 and 1 resulted in increase in the minimum percent cement in binder up to 30 percent in both ratios. With the minimum percent cement in binder, the calculated cement to sludge ratios for samples with sludge to binder ratios of 0.5, 0.75 and 1 were 0.4, 0.4 and 0.3 respectively. Leaching chromium and compressive strength of the samples with these ratios could achieve the solidified waste standard by the Ministry of Industry. For solidification of chromium sludge at sludge to binder ratio of 1, the lowest cost binder ratio of cement to lignite fly ash and baghouse filter waste in this study was 30:21:49. The cost of binder in this ratio was 718 baht per ton dry sludge.
The Effect of Partial Replacement of Cement with Crushed Waste Glass in Laterized Concrete Production
G.L. Oyekan
Research Journal of Applied Sciences , 2012,
Abstract: Technologists, engineers and scientists are continuously on the lookout for materials which can be used as substitutes for conventional materials or which possess such properties that would enable them to be used for new designs and innovations. The waste materials that can be used in making concrete are many and include both organic and inorganic wastes. These materials may be used as a binder material, as partial replacement of conventional Portland cements or directly as aggregates in their natural or processed states. This study examines the effect of crushed waste glass (CWG) when used as partial substitute for cement in laterized concrete. One mix proportion (1:2:4) of cement + CWG, sand, latente and granite coarse aggregate was used with a constant water/cement ratio of 0.65. The effect of crushed waste glass on 2 properties of laterized concrete, namely, compressive strength and workability was investigated. The results showed that the CWG did not enhance the compressive strength of laterized concrete. The compressive strength of the laterized concrete actually decreased as the percentage CWG content increased. Laterized concrete (at 25, 50 and 75% laterite content) showed an initial increase in workability with increases in percentage CWG content in the cement matrix with the maximum slump being obtained at 25% CWG content. Further increases in CWG content resulted in decreased workability. The results also showed that laterized concrete containing 50% laterite and 15% cement replacement with CWG can be used for low/medium cost housing development.
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