Studying the Behavior of Asphalt Stabilized Gepseous Soil for Earth Embankment Model

Abstract

The study presents the test results of stabilizing gypseous soil embankment obtained from Al- Faluja university Campus at Al-Ramady province. The laboratory investigation was divided into three phases, The physical and chemical properties, the optimum liquid asphalt (emulsion) requirements (which are manufactured in Iraq) were determined by using one dimensional unconfined compression strength test.in the first phase , The optimum fluid content was 11% (6% of emulsion with 5% water content).. At phase two, the effect of Aeration technique was investigated using both direct shear and permeability test. At phase three for the case of static load , the pure soil embankment model under dry test condition was investigated, The testing program included the determination of the unconfined compressive strength, direct shear strength, constant head permeability test, and one dimensional consolidation test for pure and asphalt stabilized gypseous soil. Testing was carried out in dry and absorbed conditions, the maximum pressure that can be supported before failure (ultimate sustained pressure) is 0.76 MPa with vertical settlement (0.21 mm) . However, For the pure soil embankment model under absorbed condition it was found that the maximum pressure before failure (ultimate sustained pressure) is 0.3 MPa with vertical settlement (12 mm), Which reflects the reduction in bearing capacity by (61%). Compression was made for absorbed stabilized soil and un-absorbed soil tested under hydraulic conductivity test for seven days, the results showed that a very low margin deffeneces in maximum pressure resistance and settlement were obtained (4.38 MPa , 0.11mm ) and (4.11MPa , 0.12mm).