Study On The Treatment And Monitoring Technology Of Collapsible Loess Subgrade In Ningxia Region

The Loess in Northwest China is widely distributed,mainly in the Holocene(Q4)slope loess,which is loose,porous,and has poor stability.Because of the Loess and its special engineering characteristics,especially under the action of water,the road subgrade is prone to deformability,such as subsidence,collapse and so on.The light affects the traffic safety and the heavy traffic.How to solve the roadbed and pavement disease caused by collapsible loess scientifically and efficiently has become a problem that must be solved in highway construction in the northwest loess area.At present,the treatment of collapsible loess roadbed is usually made of plain soil compaction pile,overturning,replacement and dynamic compaction.In the road subgrade design code(JTGD30-2004),the basis for the design of the collapsible loess subgrade in the highway,the standard of treatment and the effect of this method on the settlement of the collapsible loess subgrade,the requirements for the settlement of the collapsible loess foundation are very few and the phase is more general,which leads to the road collapsibility yellow.The selection,design and construction of the soil subgrade treatment methods mainly depend on the experience of the engineering construction and the reference items are more general.It is impossible to carry out the targeted,deep design and fine construction,but also lack the long-term tracking and analysis of the treatment effect.This project will be Based on the G309 Guxi Expressway,this paper analyzes the collapsible loess characteristics of Guxi Expressway on the basis of summing up the engineering experience,investigating the disease and treatment methods of collapsible loess subgrade,and puts forward the collapsibility of Ningxia through monitoring the whole process of construction and operation of the typical section collapsible loess subgrade treatment.Key technical requirements and technical parameters for design and construction of loess roadbed.While guaranteeing the quality of collapsible loess subgrade treatment of Guyuan-Xiji highway,the technology level of collapsible loess treatment in Ningxia area is comprehensively improved,which provides important technical support for the development of collapsible loess subgrade treatment technology.