Properties of concrete as influenced by the combination of different types of pozzolana derived from agricultural wastes | |
| Author | Lucero, Neil C. |
| Call Number | AIT Thesis no.ST-94-15 |
| Subject(s) | Pozzuolanas Agricultural wastes |
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering, School of Engineering and Technology |
| Publisher | Asian Institute of Technology |
| Abstract | Rice Husk Ash (RHA), Rice Straw Ash (RSA) and Peanut Shell Ash (PSA) when used individually have proven to be effective partial replacem~nt to Portland cement in concrete and mortar. These pozzolanas contained mainly amorphous silica, however the percentage of chemical compound differs in each particular pozzolana. This study was conducted to investigate the properties of mortar when Portland cement is partially replaced by different combinations of these three pozzolanas. The percentages of cement replacement were 35 percent and 50 percent. The properties investigated were setting time, compressive strength and acid resistance. Test results showed that cement pastes containing 35% PSA possessed very long initial and final setting times. On the other hand, cement pastes containing RHA possessed normal initial and final setting times of 1 hour-53 mins. and 3 hours respectively. By combining PSA with RHA, the initial setting time was extended to 2 hours-45 mins. and the final setting time to 5 hours. In effect, PSA can be regarded as a retarding admixture. The combination of RHA or RSA with PSA developed higher compressive strengths at early ages than RHA or RSA used individually. However, the effect decreased as the mortar matured. Due to its higher proportion of silica, Portland-RHA and Portland-RSA mortars developed higher compressive strengths at later ages. Portland-Pozzolana mortars possessed higher resistance against acid attack than OPC mortar. Portland-RHA and Portland-RSA possessed high resistance against acid attack while Portland-PSA mortar was very weak. Combining either RHA or RSA with PSA lowered its resistance against acid attack. |
| Year | 1994 |
| Type | Thesis |
| School | School of Engineering and Technology (SET) |
| Department | Other Field of Studies (No Department) |
| Academic Program/FoS | Structural Engineering (STE) /Former Name = Structural Engineering and Construction (ST) |
| Chairperson(s) | Pichai Nimityongskul |
| Examination Committee(s) | Karasudhi, Pisidhi ;Aoyagi, Yukio |
| Scholarship Donor(s) | Government of Japan |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 1994 |