Ph.D. Tezi Görüntüleme

Student: Fehime AKCANCA
Supervisor: Prof. Dr. Bayram Ali UZUNER
Department: İnşaat Mühendisliği
Institution: Graduate School of Natural and Applied Sciences
University: Karadeniz Technical University, Turkey
Level: Ph.D.
Acceptance Date: 25/6/2009
Number of Pages: 110
Registration Number: Di695

      Wastes appear as gradually increased environmental problem due to rapid developments in field of industry and technology. It forms major risk for human health that residential and industrial solid wastes cursorily thrown away. A lot of scientific studies have produced to reduce a minimum level of polluted environment by man. Some of those are annihilation, transforming, storing of wastes. Instead of throwing them blindly to the nature, the mostly used method to dispose the all type of waste threatening human health is to keep them in the waste disposal facilities which are designed for special goals.

In this study, it is investigated to be used sand-bentonite-lime mixtures to construct impermeable liner for sanitary landfills. For this aim, permeability and swelling pressure tests in addition to determination of geotechnical properties were performed on specimens prepared adding 0, 1, 2 and 3% of lime in sand-bentonite mixtures with 20, 30, 40 and 50% of bentonite. Five wetting-drying cycles were performed on specimens and permeability and swelling pressure values were determined at the end of each cycle.

      In the result of tests, it was found that optimum water content is increased; maximum dry density is decreased by adding lime into the mixture. Results of swelling pressure tests indicated that swelling pressure is decreased when lime is added in the mixture but partly decrement on swelling pressure is acquired in the result of wetting-drying cycles. Results of permeability tests are indicated that permeability is increased when lime is added in the mixture but decreased in case of very low lime percents. It was found that wetting-drying cycles are indicated cure effect on permeability test specimens with lime addition and therefore permeability is decreased during wetting-drying cyclic. Experimental work performed in this study showed that lower dosages (1-2%) that is less than optimum percentage of lime have lowered the permeability more than no-lime added to the mixture. It is considered that decrease of swelling pressure with the addition of lime supports the employability of sand-bentonite-lime mixture as the liner material.

Key Word:Sand-Bentonite Mixtures, Liner, Swelling Pressure, Permeability, Lime Stabilization, Sanitary Landfill, Wetting-Drying Cycle