الفهرس 
Background And Stating Of The ProblemOnly 14 pages are availabe for public view
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Abstract
Published laboratory tests results on contaminated sand with oil are compiled and represented, also extensive laboratory testing program was carried out; to investigate the effect of oil contamination on the properties of sandy soil.
The results of these experiments have shown important result, that the effect of the contamination on the shear resistance of the sandy soil is more pronounced in the internal friction angle more than cohesion, that intercept slightly change. By analyzing the data, this would provide a comprehensive idea of the behavior of contaminated soil due to the addition of oil products. Added to that, this may provide guidance and information to Engineers and researchers in the future.
In order to study the effect of oil products on sandy soil, it would be important to find soils with different gradations and oils also with different viscosity, so six different samples of soil and nine oil products were chosen in research. The values of kinematic viscosities were 2.71, 2.76, 3.25, 4.5, 6.31, 34.3, 37, 200 and 460 centistokes.
The amount of up to 10 percent by weight of dry soil samples selected as oil contamination. Moreover, the ultimate bearing capacity of contaminated sand was predicted for an isolated footing 2x2 m. On bases of the results of this research, the following conclusions can be provided:
1. In case of loose conditions (at Dr = 20%), as the oil percentage increases from 2% to 10%, the reduction of the angle of shearing resistance (ⱷ) is about (10 - 17%) with oil its viscosity 2.76 centistokes, about (17 - 23%) with oil its viscosity 6.31 centistokes, about (23 - 44%) with oil its viscosity 37 centistokes, about (41 - 52%) with oil its viscosity 200 centistokes and about (44 - 57%) with oil its viscosity 460 centistokes
2. In case of medium dense conditions (at Dr = 50%), as the oil percentage increases from 2% to 10%, the reduction of the angle of shearing resistance (ⱷ) is about (11 - 18%) with oil its viscosity 2.76 centistokes, about (18 - 25%) with oil its viscosity 6.31 centistokes, about (34 - 45%) with oil its viscosity 37 centistokes, about (38 - 51%) with oil its viscosity 200 centistokes and about (42 - 55%) with oil its viscosity 460 centistokes.
3. In case of dense conditions (at Dr=80%), as the oil percentage increases from 2% to 10%, the reduction of the angle of shearing resistance (ⱷ) is about (13 - 20%) with oil its viscosity 2.76 centistokes, about (22 - 28%) with oil its viscosity 6.31 centistokes, about (32 - 42%) with oil its viscosity 37 centistokes, about (36 - 50%) with oil its viscosity 200 centistokes, and about (41 - 53%) with oil its viscosity 460 centistokes.
4. This reduction in angle of shearing resistance due to the lubrication and slippage of the soil particle caused by the presence of the oil product.
5. Consequent to the decrease in the soil friction angle upon the oil contamination, the ultimate bearing capacity remarkably decreases.
6. By generally increasing the oil viscosity from 2.71 to 460 centistokes and at an oil percentage of 2%, the reduction in the ultimate bearing capacity has been found ranging from (22% to 69%), (28% to 70%) and (35% to 77%), at relative densities, Dr, of 20, 50 and 80%, respectively.
7. At an oil percentage of 5%, the reduction in the ultimate bearing capacity has been found ranging from (25% to 72%), (36% to 76%) and (45% to 81%), at relative densities, Dr, of 20, 50 and 80%, respectively.
8. At the maximum examined oil percentage of 10%, the reduction in the ultimate bearing capacity has been found ranging from (33% to 73%), (39% to 78%) and (49% to 83%), at relative densities, Dr, of 20, 50 and 80%, respectively, because the contaminated soil will more easily be compressed into denser configurations due to the lubrication of the soil particles.
9. By increasing the oil percentage from 2% to 10%, the reduction reach (49% to 83%), which is almost half to three quarters of the soil capacity, will be lost.