Buscar
Mostrando ítems 1-10 de 3232
Sulfate performance of calcined illitic shales
(Elsevier, 2021-07)
In the past, calcined pozzolans were largely used in massive concrete, and nowadays, they appear as an excellent alternative to reduce the clinker factor in general use cement. The pozzolanic activity of two calcined illitic ...
Concretes with Calcined Clay and Calcined Shale: Workability, Mechanical, and Transport Properties
(American Society of Civil Engineers, 2020-05-30)
This paper analyzed the eco-efficiency of concretes (water/cement ratio = 0.50; cement content=350 kg/m3, and slump = 7 cm) with blended cement containing 25% by weight calcined pozzolan obtained from a low-grade kaolin ...
Agronomic evaluation of calcined crandallite from three Brazilian phosphate deposits
(TAYLOR & FRANCIS INC, 2008)
Samples from the weathering mantle containing crandallite of three Brazilian phosphate deposits, Tapira, Catalo, and Juqui, were characterized, calcined, and agronomically evaluated. The calcination process increased total ...
Effect of Calcination Temperature on the Photocatalytic Activity of Nanostructures Synthesized by Hydrothermal Method from Black Mineral Sand
A nanostructured material from black sand, whose structure is composed by Fe2O3 and TiO2 oxides, was prepared via hydrothermal treatment (at 120 °C for 72 h), The starting mineral (as-synthesized nanostructure) was ...
Kaolinitic calcined clays - Portland cement system: Hydration and properties
(Elsevier, 2014-08)
This paper examines the influence of type of kaolinite in the raw clay on the performance of calcined clays as supplementary cementing materials. Two kaolinitic clays were characterized, calcined then ground and used as ...
Pozzolanic activity of calcined halloysite-rich kaolinitic clays
(Elsevier Science, 2017-10)
The aim of this study is to determine the pozzolanic activity of clays with high content of halloysite/kaolinite, and to evaluate the influence of halloysite/kaolinite ratio and halloysite morphology in the development of ...
Thermal Treatment and Pozzolanic Activity of Calcined Clay and Shale
(American Concrete Institute, 2019-07)
Clayminerals are the most abundant raw materials for calcined pozzolans. Thermaltransformation includes dehydration, dehydroxylation, mineral collapse, andneo-formation. Depending on the type and amount of clay mineral, ...
Thermal analysis to assess pozzolanic activity of calcined kaolinitic clays
(Springer, 2014-04)
The use of calcined clays as partial replacement of cement is encouraged since it promotes the reduction of the green-house gas emission and the energy requirement of cement-based material, maintaining or enhancing the ...