Title: Characterization of Chemical Treatment Method for Rice Husk Ash Cementing Materials

Author(s): Lapyote Prasittisopin and David Trejo

Publication: Symposium Paper

Volume: 294

Issue:

Appears on pages(s): 1-14

Keywords: Rice Husk Ash, Cementing Materials, Improved Characteristics, Chemical Treatment Method, Sustainability.

DOI: 10.14359/51686324

Date: 10/4/2013

Abstract:
Rice husk ash can be used as a supplementary cementing material. It is a waste material from the burning of rice husks for energy. Rice husk ash contains a mesoporous morphology of silica and this morphology has high hydrophilic properties. When rice husk ash is used in concrete mixtures, the flowability of the mixtures decreases. This makes the acceptance of rice husk ash in the concrete industry more challenging. Reduced workability hinders the potential use of rice husk ash in the field. Some research has investigated the potential use of using mechanical grinding (e.g., ball mill) to reduce particle size of rice husk ash with the hopes of improving the workability of concrete containing RHA, but this method requires significant energy and results in high wear of the equipment. The work investigates the use of a chemical treatment process of rice husk ash. This chemical treatment process reduces the particle size and breaks down the mesoporous morphology, thereby improving the fresh characteristics of concrete containing RHA and decreasing its water requirements. Because changes in setting behavior and reduced early-age strength development are other concerns when using some supplementary cementing materials, this work also investigates the setting, early-age compressive strength development, and porosity of cementing material systems containing 10% and 15% RHA replacements.