Feasibility study of using natural pozzoloans from Democratic Peoples Republic of Lao as partial replacement of cement in roller compacted | |
| Author | Jadhav, Mandar |
| Call Number | AIT Thesis no.ST-07-12 |
| Subject(s) | Pozzuolanas--Laos Roller compacted concrete |
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering in Structural Engineering, School of Engineering and Technololgy |
| Publisher | Asian Institute of Technology |
| Series Statement | Thesis ; no. ST-07-12 |
| Abstract | This study includes the feasibility study of natural pozzolana to be used in roller compacted concrete. Physical and chemical properties of natural ashes were investigated. The aggregates were supplied by GMS Power Ltd. from Democratic Peoples Republic of Lao; physical properties of aggregates were investigated followed by grading of coarse aggregates. The mixture proportioning was carried out for the Roller Compacted Concrete; High Paste Method was adopted for mixture proportioning. In addition to 3 trial mixtures, 11 mixtures were prepared and sample specimens were prepared in laboratory. Variables for the mixture proportioning were mortar volume (50%, 55%, 60%), type of pozzolana (volcanic ash, silicified volcanic ash, rice husk ash, rice husk ash type II and fly ash) and coarse aggregate gradation( 35:35:30 and 55:25:20).The sample specimens were tested for compression and tension at 7, 14 and 28 days after casting. In addition to hardened properties fresh properties like vebe time and vebe or fresh density was also examined. The cement replacement was kept constant where as the vebe time was kept between 15 to 30 sec. and the other parameters were varied in the range. To compare the performance of volcanic ash and silicified volcanic ash, RCC mixtures with fly ash, rice husk ash and rice husk ash type II was also prepared and tested for the fresh and hardened prope1ties. Volcanic and silicified volcanic ash possessed the chemical composition that satisfied the ASTM requirements, except pozzolanic activity index. Concrete mixtures in which volcanic and silicified volcanic ash were used performed satisfactorily in tests for fresh and hardened properties. The minimum strength in compression was 155 kg/cm2 where as minimum tensile strength was 17 kg/cm2. Optimum mixture was found with 55 % mortar volume, coarse aggregate gradation of 55:25:20 and volcanic ash in 70% replacement of cement. This mixture had satisfactory Fresh (Vebe time 32 seconds) and hardened (compressive strength 15 kg/cm2 and tensile strength 17 kg/cm2 ). In comparative study Fly Ash performed in most positive way, the concrete containing fly ash as a pozzolana had the highest strength (compressive and tensile). Rice Husk Ash has excellent physical and chemical properties, resulting very good concrete in which same was used as partial replacement to cement. On the other hand concrete with rice husk ash type II produced concrete with unsatisfactory hardened properties. |
| Year | 2007 |
| Corresponding Series Added Entry | Asian Institute of Technology. Thesis ; no. ST-07-12 |
| Type | Thesis |
| School | School of Engineering and Technology |
| Department | Department of Civil and Infrastucture Engineering (DCIE) |
| Academic Program/FoS | Structural Engineering (STE) /Former Name = Structural Engineering and Construction (ST) |
| Chairperson(s) | Pichai Nimityongskul; |
| Examination Committee(s) | Kato, Yoshitaka;Raktipong Sahamitmongkol; |
| Scholarship Donor(s) | Gargi Packing Industries, India;AIT Fellowship; |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 2007 |