Aeolian Sand Subgrade Construction Technology And Dynamic Response Analysis Under Traffic Load

The desert is distributed extensively in China, it contains abundant mineral resources in desert regions. But, the studies in the compaction property, the method for determining maximum dry density and the construction technology of aeolian sand still needs further study. Also, with the phenomenon of the increasing road traffic, speeding and overloading is widespread, there is a huge difference between the existing subgrade design considered vehicle load as static loads and real situation. And the difference increased significantly with increasing of the axle load and speed of vehicles. It becomes an inevitable trend that the subgrade design theory developed from the static system to dynamic. Therefore, this paper systematically studied the aeolian sand compaction technology and dynamic characteristics under traffic loads through the theoretical analysis, laboratory test, field test, numerical analysis and others. Details are as follows:(1) Through a large number of laboratory tests, this paper analysis of the fundam- ental featurees of aeolian sand to provide a theoretical basis for the study of the aeolian sand compaction technology.(2) Through the analysis of mechanism of compaction of standard heavy compaction test and vibration compaction test, this paper compared two methods of compaction effect, especially the effects of fines content. Finally it proposed the more reasonable method for determining the maximum dry density.(3) Combined of laboratory tests, we carried out the field compaction test in order to obtain the best compacting effect of the aeolian sand subgrade. Finally it proposed the construction technology when the vibratory rollers and medium-sized bulldozers are adopted to crush.(4) Through simplying the vehicles to a quarter vehicle model with two degrees of freedom,this paper determined the calculation of the additional dynamic load,and established simplified models f traffic load.(5) Respectively utilizing the moving harmonic load and the half-wave load to simulate the one-time effect and long-term effects of traffic load, this paper systematic research on the dynamic response of the aeolian sand subgrade.