Abstract: In order to analyze the influence the second phase expansion engineering of the Yunnan Qiujialingzi phosphogypsum slag reservoir on the Guiyang-Kunming railway roadbed located on the east side of the slag reservoir.Two typical cross sections of the east of the slag reservoir are selected to conduct finite element simulation based on the BCF plane finite element software developed by the institute of geotechnical engineering,Hohai University,so as to study the influence of the expansion of the slag reservoir on the the deformation of railway roadbed,besides that,the stress deformation and stability of the roadbed and slag reservoir are discussed in detail.During the simulation analysis process,the simulation of the soil mass is conducted by adopting Dengken-Zhang fei nonlinear constitutive model.The results show that due to the roadbed of roadway is located the limestone distribution area with high intensity,therefore,the influence of the expansion of the slag reservoir on the deformation of roadway roadbed is small,that is to say,the normal operation of roadway can not be affected.The feasibility and rationality of the expansion scheme of the slag reservoir is verified based on the above simulation analysis in this paper.

Key words: Slag reservoir, Stress deformation, Finite element method, Roadbed