Stability And Bearing Capacity Of The Annular Reinforced Protecting Wall Around Oil Tank

The reinforced protecting wall is a composite structure located around the oil tank.It is consisted of three parts,which is the backfill soil,reinforcements arranged in the soil and geogrid panels respectively.The reinforced protecting wall is starting to be used in petrochemical industry with the advantages of low cost,simple construction,aesthetic appearance,undemanding foundation,strong deformation compatibility,good seismic performance and good protection performance.Experts from china and abroad have been carrying out a lot of tests and theoretical studies on the behavior of geosynthetic reinforced soil walls on the rigid foundations,and many current design criteria are partly based on these researches.However,the reinforced protecting wall has received very few attentions,and those researches haven't taken the influence of spatial character on the reinforced protecting wall into consideration.As a result,its theoretical researches lag behind its engineering application currently.This paper will focus on reinforced protecting wall constructed around the oil tank and gives a systematic research.The main contents of the study are as follows,Investigate the geogrid interaction characteristics by using the improved direct shear apparatus.These tests will help to do a more systematic study on the key factors to the behavior of geogrid interaction,including the type of geogrid,the water content of soil,and the rate of shear.The result of interaction shear direct test can be used in parameter selection of the finite element modeling.A project case of reinforced protecting wall built around the oil tank is introduced briefly at first.Next,a finite element analysis software is used to simulate the project to verified the feasibility of using the reinforced protecting wall around the oil tank.This paper conducts a detail study on the influence of the size of reinforced protecting wall on the serviceability limit state,which is composed of deformation behavior,the foundation settlement,and the distribution of strains and tensile in the reinforcement.According to the above analysis,this paper puts forward some suggestion to optimize shape and size of reinforced protecting wall.The paper analyzes the changes of the deformation characteristics and mechanical properties under the change of reinforced protecting wall's parameters.In addition,the effect of construction quality on the performance of protecting walls is investigated as well.A thoroughly studies on the influences on upper protecting walls from parameters,such as geogrid stiffness,geogrid stiffness and the parameters of filled soil,is conducted.By comparing safety factors given by the limit equilibrium method and the strength reduction finite element method the stability of reinforced protecting walls is discussed.At the same time,the parameters of protecting wall,such as interface strength,strength of soil and geogrid length,is also studied in this paper,for these parameters also affect the stability of the protecting wall.The paper summarizes the primary conclusions from the study,and points out the shortcomings and the future work as well.