Numerical Simulation Of Expansive Soil Subgrade Modified By Lime And Coal Gangue

Expansive soil is a problem soil in highway construction,which need to take measures to deal with in order to be used to fill subgrade.A large of coal gangue produced from coal mining in Inner Mongolia,which is the biggest coal producing province in China.Coal gangue as the waste of coal producing has polluted the environment around mining. In this paper, lime and coal gangue were added into expansive soil, which not only improve the engineering properties of the expansive soil,but also exploit the coal gangue reasonably, so as to achieve a win-win objective.The mixture ratio of lime to coal gangue to expansive soils was choose to 0:0:100, 3:6:91,4:8:88,5:10:85 and 6:12:82, respectively, and the optimal dosage was determined by the test of the expansion ratio and unconfined compressive strength. Then the influence of embankment height and permanent loads to the subgrade stability under the optimal dosage was studied by the ANSYS finite element analysis.The optimal dosage of lime to coal gangue to expansive soils was determined to 4:8:88 by the tests. The ANSYS finite element analysis showed that the slope and the foot of the slope of the subgrade were damaged easily with the increase of the height of the filled subgrade under the optimal dosage, of which the stability was mainly determined by the weight of the earth filled into the subgrade, and the load of the structure of the pavement and the vehicle showed considerable influence to the low subgrade...