An Initial Discussion On Treatment Of Foundation In Collapse Loess With Large Thickness Conditions

There has a large area of collapsible loess distributing in China, and the Chinese loess is famous in the world as broad cover and great thickness, especially the North West Territories is remarkable. Along with the development of economy, the current urban construction scale is increasing,and land for construction is dwindling, For full utilization of land resources, the author puts forward the policy-"push the stone to fill the sea,make the land with mountain", however, based on the condition of soil, covering the northwest soil for most of collapsible loess, and under the condition of the" make the land with mountain", how to deal with the foundation that meet the requirement of the project and foundation of the selection of the discussion is becoming increasingly fierce, past the foundation treatment of the basic technology of the selection standard already cannot meet the needs of the actual project, the urgent need to study for large thickness of collapsible loess foundation treatment technology conditions and basis.As the adverse impact of construction projects,loess collapsibility is one of the study factors that have been issued as a key point. In order to eliminate loess collapsibility against the project,both at home and aboard,many scholars and engineers invents and summarizes many ways in the process of exploring and engineering practice.The whole ways can be divided into two categories,one is through the loess soil of the pile foundation,and the other is to improve the soil or foundation treatment reinforced.Cushion method.dynamic compaction.compaction and pre-soaking method are effective ways to collapsible loess foundation.As to the site which the thickness of loess soil is not large, after the above-mentioned ways,the foundation soil collapsibility removed,the capacity increased and the deformation reduce,which can meet the engineering requirements.However,the site which the thickness of loess soil is large,in order to achieve the national regulatory requirements of eliminates the depth of collapsible soil,the above-mentioned methods(except for pre-soaking method)are very difficult to achieve technicallyin many cases and economically very unreasonable.Systematically, based on further analysis from the collapsible loess foundation treatment theory and the advantages and disadvantages of the foundation, on the basis of a project example from Northwest for big thickness of collapsible loess foundation treatment and the basic selection for the engineering application, the in-depth analysis and discussion, in view of excavation,fill and natural foundation, three different foundation site condition, to contrast the foundation treament and basic selection plan, and choose the best plan make it more reasonable applied in the project.