Aseismic Analysis On Integral Retaining Wall Of Large Diameter Circular Coal Yard

Large diameter circular coal yard has good application in electric power industry,because of its advantages of smaller occupation of land,higher storage capacity of coal,higher degree of automation,easier coal blending,more safe and reliable operation,higher resistant ability to bad weather,less pollution to the environment,less coal loss,and better landscape.The structure form of circular coal yard is monotonous,which composed of two main parts of spherical lattice shell on the top and retaining wall under that,and the retaining wall structure could be divided into two types of separation and integral.The integral retaining wall structure has been developed rapidly in recent years because of its advantages of better integrity,less materials and area occupied comparatively.At present,there are few domestic and foreign research,then,it is well importance to research deeply on the natural vibration characteristics,deformation and mechanical characteristics of the structure under rare earthquake.Based on the study of dynamic characteristics,the modal analysis and the elastic-plastic dynamic analysis was carried out on the structure of integral retaining wall.The following works have been done:(1)Load conditions were analyzed,seismic waves were selected,and the 3-D finite element model of the integral retaining wall structure was established,according to the practical project;(2)The modal analysis was carried out with two calculation schemes to research the nature vibration characteristics of the integral retaining wall structure,then,weak parts were analyzed;(3)The elastic-plastic dynamic analysis was carried out on the integral retaining wall structure,to research the deformation and mechanical characteristics under rare earthquake;Results show that,the integral retaining wall structure has high stiffness;the mass distribution of the retaining wall structure is influenced deeply by the unfavorable live-load distribution;there will be the weak parts nearby the opening because abrupt change in stiffness;displacements on the top of buttress columns and stresses at the bottom of the retaining wall are seriously affected by the unfavorable live-load distribution and opening;the maximum displacements on the top of buttress columns under earthquake occurs along the normal direction of the circumference;the maximum horizontal stresses at the bottom of the retaining wall under earthquake occurs along the circumferential direction,and the vertical stresses larger than horizontal.Suggest that,the torsional effects of buttress columns should be fully considered in design;the displacements on the top of buttress columns should be strictly limited to provide stable support for the spherical lattice shell on the top;the reinforcements at the bottom of the retaining wall should be properly increased to bear the stresses under earthquake.