Soil Arching Effect And Distribution Of Earth Pressure Under Different Displacement Modes

As the focus of China's transportation infrastructure construction gradually shifts towards the central and western regions,there are more and more special sections such as high-filled embankments,high and steep slopes,and soft foundations.How to effectively ensure the stability of the roadbed slope or control the settlement of the foundation is an engineering sector Concerned hot issues.In many options,anti-sliding piles,retaining walls,composite foundations and other technologies have been widely applied and have achieved good results.In spite of this,many researchers have found that soil arching effects are commonly found in soil-structure due to inevitably inhomogeneous deformation between soil and structure,not only for supporting structures but also for composite foundations,through field tests,model tests,and theoretical analysis.Redistribution of stress occurs,causing more obvious stress concentration in the structure.However,the current research on this phenomenon is still in the preliminary discussion stage,and its theoretical system is still far from meeting engineering practice.Therefore,the impact of soil arching cannot be properly considered in engineering design.Based on this research status,in order to further clarify the key influencing factors of vertical and horizontal soil arching effects,and the change law of soil-structure load sharing effect,in order to improve the relevant design calculation methods,this paper adopts indoor vertical and lateral movable door tests.Methods,taking into account the influence of the width of the movable door,the inhomogeneous displacement and the displacement pattern,the dynamic evolution law of the soil arching effect and the load-sharing effect of the soil-structure load were explored,and the following main conclusions were proposed:1.In the vertical soil arch effect active gate test,after active displacement of the active gate,the earth pressure on the baffle increases,and the earth pressure on the movable plate decreases due to the effect of the soil arching effect.When the displacement of the movable door increases,the earth pressure on the baffle increases and the earth pressure above the moving door decreases.After the passive door is passively displaced,the earth pressure on the baffle decreases,and the movable plate decreases.The earth pressure increases due to the effect of the earth arch effect.And when the displacement of the movable door increases,the earth pressure on the baffle continues to decrease while the earth pressure above the active door continues to increase.2.When the active door is actively displaced,the critical displacement when the sand earth pressure on the movable plate is stable is ?1=(0.03?0.04)w,and the critical displacement when the sand earth pressure on the baffle is stable is?2=(0.150.2)w.When the movable door is passively displaced,the critical displacement when the sand earth pressure on the movable plate is stable is?1=(0.05-0.4)w,the critical displacement when the sand earth pressure on the baffle is stable is ?2 =(0.02-0.1)w.3.For the lateral soil arching action gate test,when the active gate produces active displacement,the lateral earth pressure is expressed as the earth pressure in front of the movable plate is greatly reduced,and with the increase of the active displacement,the wall is laterally Earth pressure shows a gradual decrease.When the movable plate produces passive displacement,the lateral earth pressure shows a significant increase in the earth pressure before the movable plate,and with the increase of the active displacement,the lateral earth pressure of the wall is gradually increasing.4.In different active and passive displacement modes,when the width of the movable door is constant,with the increase of pile width ratio B/w,the load sharing ratio of pile and soil becomes gradually smaller,and the ability of the soil itself to bear the load is fully mobilized.The arching effect is more and more obvious,and the changing rules are the same under different door width conditions.The calculation formula of the horizontal earth pressure and the arbitrary wall height of the horizontal earth pressure under different widths of the movable door with arbitrary displacement patterns is proposed:(?),(?)(?).