Actividad Puzolánica de una roca volcánica zeolítica
The main objective of the paper it is to characterize a Cuban zeolitic rock in order to establish their usability as pozzolanic components in cements. Additionally modifications in microstructure, composition and structure of the hydrated cement paste with 20% addition of zeolitic rock have been eva...
| Authors: | , , , , |
|---|---|
| Format: | article |
| Publication Date: | 2008 |
| Country: | España |
| Institution: | Consejo Superior de Investigaciones Científicas (CSIC) |
| Repository: | DIGITAL.CSIC. Repositorio Institucional del CSIC |
| OAI Identifier: | oai:digital.csic.es:10261/5443 |
| Online Access: | http://hdl.handle.net/10261/5443 |
| Access Level: | Open access |
| Keyword: | Zeolitic rocks pozzolanicity porosity 29Si MAS NMR FTIR C-S-H gel |
| Summary: | The main objective of the paper it is to characterize a Cuban zeolitic rock in order to establish their usability as pozzolanic components in cements. Additionally modifications in microstructure, composition and structure of the hydrated cement paste with 20% addition of zeolitic rock have been evaluated. The samples were characterized using XRD, FTIR, BSE/EDX, optical microscopy 29Si MAS NMR and BET specific surface techniques. The studies showed the Carolinas rock to be hypocrystalline and contain subautomorphic and automorphic heulandite and/or clinoptilolite crystals, allotriomorphic calcite crystals - and small, unevenly distributed masses of Fe and Ti oxide. Pozzolanic activity of the material has been tested at 14 and 60 days in contact with a portlandite saturated solution. The C-S-H gel formed has been characterized. Replacement of 20% of cement by zeolitic rocks increases the amount of C-S-H gel formed as decreases calcium aluminates hydrates. Composition of the formed gel with and without zeolitic rocks are unlike in terms of calcium and aluminium content. NMR studies revealed that chains length of C-S-H gel formed increases with the zeolitic rock addition. Finally pozzolan additions produce less porous pastes as well as refine the porous size. |
|---|