| Author | Kamruzzaman, A. H. M. |
| Call Number | AIT Thesis no. GE-97-15 |
| Subject(s) | Soil stabilization--Thailand--Bangkok
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| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering, School of Civil Engineering |
| Publisher | Asian Institute of Technology |
| Abstract | Strength and compressibility characteristics of soft Bangkok clay treated chemically with different types of additives (cement, lime & fly-ash) and salt solutions (NaCl & N~S0 ) were investigated through a series of unconfined compression and oedometer consolidation tests in which additive contents, salt contents and curing time were considered. Cement and lime contents were varied from 2 to 10%, fly-ash 10 to 100% and salt contents were 0.5 to 3 % considering 1 month curing period. Cement slurry having water-cement ratio of 0.25 and salt solutions with a total water content of200% were used. Dry mixing method was used for lime and flyash additives. Water content and plasticity were reduced by increasing the additive contents. Due to high organic contents in the base clay, the minimum amount of additives required were 5% cement, 2% lime and 50% fly-ash to improve the strength and compressibility characteristics of soft Bangkok clay. The unconfined compressive strength of treated clay increased with increasing additive contents and 10% cement, 5% lime and 100% fly-ash were found to be effective for 1 month curing period. Unconfined compression tests were also conducted for the use of flyash with cement and lime additives. The test results showed that the strength increased substantially with increasing the amount of flyash while the percentages of cement and lime content were constant. The oedometer test results revealed that the consolidation properties improved significantly by increasing _the additive contents; considering the apparent increase in preconsolidation pressure ( crP ), reduction in compression index (Cc). a~1d enhan~ement of coefficient of consolidation ( Cv ). The high pressure oedometer tests (consolidation pressure 6400 Kpa) for cement and lime additives also showed similar improvement of consolidation properties as of conventional consolidation tests (consolidation pressure 1600 kpa). The test results show that at high pressures the void ratio decreased significantly which was found to be similar to that of the normally consolidated state of the untreated clay. Also at consolidation pressures higher than the preconsolidation pressure, destruction of the initial strncture was supposed to be incurred and the rest of the curve became parallel to the lower part of the untreated clay. Furthermore, unconfined compression and oedometer consolidation tests had been done to investigate the effect of salt solutions on soft Bangkok clay. The test results showed that 5% lime with 0.5% NaCl and 25% fly-ash with 0.5% NaCl improved the strength and compressibility properties more than that of 5% lime and 25% fly-ash only. Unconfined compression and oedometer tests were also investigated for salt solutions only, having the salt content varied from 1 to 3%. It was found that the salt solutions were not to be effective to stabilize the soft Bangkok clay. |
| Year | 1998 |
| Type | Thesis |
| School | School of Civil Engineering |
| Department | Department of Civil and Infrastucture Engineering (DCIE) |
| Academic Program/FoS | Geotechnical Engineering (GE) |
| Chairperson(s) | Balasubramaniam, A.S.; |
| Examination Committee(s) | Bergado, D.T. ;Shibuya, S.;Lin, Der Guey; |
| Scholarship Donor(s) | Asian Development Bank (ADB), Japan; |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology |