Research On Seismic Response And Expansion Of Soda Slag Dam On Soft Soil Foundation

The tailings dam is a structure around the tailings pond that is used to store tailings.It is a special industrial building in the waste disposal project,which is one of the important facilities for the disposal of waste in industrial production.However,with the increasing height of waste accumulation in tailings ponds,it has also become a high potential energy hazard.The soda slag dam studied in this dissertation is a kind of tailings dam,which is located on the soft soil foundation and is mainly used for stacking the soda slag produced during the production of soda ash.If the tailings dam is destabilized under seismic loading,it will pose a major threat to the life and property safety of downstream people and the ecological environment.Therefore,it is of great engineering significance to investigate the seismic response characteristics and stability of soda slag dams during the production phases as well as in the raising and expansion scenarios.Based on the principle of seismic response dynamic analysis,the ABAQUS threedimensional finite element models are established by relying on the two typical sections of the No.3 soda slag dam near the river and the sea of a coastal soda slag plant.The dynamic response characteristics and slope stability under seismic action are analyzed to the current sections;According to the results of the analysis of the current sections,combined with the actual situation of the project,the dam heightening and expansion scheme was studied.The dynamic response characteristics of heightened sections under seismic action and slope stability are analyzed by means of finite element simulation to verify the reasonableness of the heightened and expanded research.The main research work of this dissertation is as follow:(1)Research on the seismic response of tailing dams and soft soil foundation reinforcement measures.The relevant research literatures are consulted to understand the research status of the seismic response for tailings dam and the seismic reinforcement technology.Based on the basic conditions of the project,combined with relevant geological survey data and codes,the relevant calculation parameters of the seismic response for the soda slag dam are obtained.(2)The analysis of the seismic response and slope stability for current sections of the soda slag dam are carried out in accordance with the establishment of threedimensional finite element models.By analyzing the horizontal dynamic response characteristics of the characteristic points for the current sections,as well as the total displacement and stress distribution at the moment of maximum relative sliding of the slope during the earthquake,the distribution law of the seismic response of the current sections are obtained.The finite element strength reduction method is used to calculate the safety factor of slope stability.(3)According to the analysis and research on the seismic reinforcement measures of the tailings dam and the actual situation of the project,the dam heightening and expansion plan is formulated.As the dam is heightening and expansion,the stability of the raised dam will be further reduced.Therefore,it is necessary to consider the reinforcement of dam and foundation in order to maintain its stability in earthquakes.The combination of high-pressure jet grouting pile reinforcement and enhancement of the dam's seepage drainage capacity is adopted in the study to strengthen the soda slag dam for earthquake resistance.(4)By establishing three-dimensional finite element models,the rationality of the heightened and expanded plan is verified.The dynamic response characteristics and slope stability of the heightened and expanded sections are analyzed through finite element numerical simulation,and compared with the analysis results of the current sections to investigate the rationality of the study.