Quantification of hydrated cement products of blended cements in low and medium strength concrete using TG and DTA technique

Hydration Kinetics and Fire Resistance of Recycled Low Grade Alumino-silicate Refractory Bricks Waste-metakaolin Composite Cement Pastes

“…The third endothermic peak located at range 410-475 o C is due to the decomposition of CH [35], with a mass loss of 3.50 and 4.34 % for 3 and 90 days, respectively. The last endothermic peak located with temperature range 700-780 o C is due to the decomposition of CaCO 3 [35,37], with mass loss of 6.50 and 10.27 % for 3 and 90 days, respectively. It is clear that the second endothermic peak located at about 150 o C increases with curing time due to the formation of excessive amounts of C-A-H and C-A-S-H as well as C-S-H.…”

“…The third endotherm at 448-443 o C is due to the dehydroxylation of CH [35], with a mass loss of 3.02 and 4.09 % for 3 and 90 days, respectively. The last endothermic peak located at 730-738 o C is due to the decomposition of CaCO 3 [35,37], with mass loss of 5.89 and 7.48 % for 3 and 90 days, respectively. Also, the CaCO 3 is still present, due to the carbonation of CH by atmospheric CO 2 .…”

“…These values indicate that the ASRBs have little pozzolanic activity with CH. The fourth endotherm with the range 685-760 o C due to the decomposition of amorphous and crystalline CaCO 3 [35,37], with a mass loss of 6.50 and 10.13 % for 3 and 90 days, respectively. These phases are formed as a result of the pozzolanic activity of ASRBs with CH [11].…”

Sistemas cimento, cinza volante e cal hidratada: mecanismo de hidratação, microestrutura e carbonatação de concreto.

“…A alteração microestrutural por atividade pozolânica da cinza volante substitui a portlandita, composto químico lixiviável, por hidratos estáveis à ação da água. Como resultado há o refinamento dos poros, aumento da tortuosidade da rede capilar e, sobretudo, densificação da zona de transição, melhorando o desempenho do concreto frente à maioria das ações deletérias a que estará exposto (ISAIA, 1995;PAULON, 2005;VEDALAKSHMI et al, 2003).…”

Desarrollo de conglomerados con la incorporación de cenizas volantes procedentes de la incineración de residuos sólidos urbanos

“…Dejando a un lado la deshidratación del agua estructural sufrida hasta 120ºC de temperatura (Bakolas et al, 1998), la primera señal importante se produce entre 368,06ºC y 501,21ºC, y es debida, principalmente, a la superposición de las descomposiciones del hidróxido cálcico (Ca(OH) 2 ) y del hidroxicloruro cálcico (CaClOH) (Rajammal et al, 2009;Sepulcre-Aguilar y Hernández-Olivares, 2010;Vedalakshmi et al, 2003).…”