Influence of pozzolans on mechanical properties of cement colum | |
| Author | Lirar, Hussain |
| Call Number | AIT Thesis no.ST-07-08 |
| Subject(s) | Pozzuolanas Columns, 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 Technology |
| Publisher | Asian Institute of Technology |
| Series Statement | Thesis ; no. ST-07-08 |
| Abstract | Ground settlement is one of the major crises in Bangkok due to low bearing capacity of soft clay material, causing problems of low stability and high settlement. These problems could be overcome by cement columns; hence this research focuses on finding the influence of pozzolans on mechanical properties of cement column. The primary objective of this study was to investigate the influence of different pozzolans on mechanical properties of cement column when part of Portland cement was replaced by pozzolans. The research also focuses on finding an effective mix design that may be used in the construction of cement column by slurring mixing with optimum strength at optimum water cement ratio. Emphasis is placed on using locally available raw material to achieve the set goal. The test results showed that soft clay treated with cement and a combination of cement-pozzolans improved the stability and settlement of the ground by increasing the bearing capacity and shear strength of the treated soil. The unconfined compressive strength has improved with replacing definite amount of cement by pozzolans at higher binder contents (200kg/m3 ) while showed a decreasing strength with increasing pozzolans percentage at lower binder content ( 100 kg/m3 ). The setting times of cement column were found to be significantly delayed as compared with those of cement paste. Moreover soil-cement treatment with pozzolans used in this study further delayed the setting times. The highest strength was achieved by replacing 25% of cement to rice husk ash type-I at a binder content of 200kg/m3, while cement-fly ash combination was found to be the most economical binder for deep mixin methods giving 30-40% replacement of cement to fly ash at binder content of 200 kg/m3. The mechanical properties of treated clayey soil were greatly influenced by the presence of pozzolans. Different pozzolans gave different strength at different percentage replacement of cement. Cement in combination with fly ash was found to be the most economical binder for deep mixing methods. |
| Year | 2007 |
| Corresponding Series Added Entry | Asian Institute of Technology. Thesis ; no. ST-07-08 |
| 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) | AIT Fellowship; |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 2007 |