Research On Mechanical Performance Of Railway Passenger Station With Concrete Thin Shell Structure

With the development of national economy and transportation infrastructure,in order to fully show the appearance of the city,a large number of small and medium-sized railway station buildings at this stage adopt the design concept of combining concrete thin shell structure with reinforced concrete frame structure.However,there is a lack of systematic and in-depth research on the seismic performance of concrete thin shell structures,and the proposed values of design type parameters of various thin shell structures have not been provided.To sum up,in order to improve the safety of thin shell structures,this paper will carry out the research on the seismic performance and mechanical performance of concrete thin shell structures,and the research results can provide a basis for the design of such structures.In this paper,ABAQUS finite element simulation is used to study the seismic performance of concrete cylindrical shell structures and hyperbolic flat shell structures,and the influence of structural parameters and opening forms on their mechanical properties,which provides theoretical basis for practical engineering structure design.The main contents are as follows:(1)Combining the natural vibration period,frequency and mode mode of the structure,the dynamic characteristics of the structure are analyzed,and it is found that the natural vibration frequency distribution of the structure is dense,and the structure is dominated by horizontal vibration and torsional vibration.The seismic performance of thin shell structure is studied by analyzing the displacement,acceleration and stress distribution of column top under rare earthquakes.The results show that the maximum displacements of cylindrical shell and hyperbolic shell are 1/200 and 1/60 respectively,both of which are less than 1/50 of the standard value.The damage of thin shell structure caused by rare earthquakes is distributed at the bottom of the column,and the structure meets the requirement of "not failing in big earthquakes".(2)The effects of beam span ratio and plate thickness on the mechanical properties of cylindrical shell and hyperbolic flat shell structures are studied.The results show that the Angleα between shell and beam has a great influence on the selection of beam span ratio.The increase of α Angle leads to the increase of structural axial force and the decrease of shear force,and the utilization rate of compressive properties of materials is improved.The higher the vector span ratio,the smaller the thickness of thin shell structure,that is,the recommended range of 0.1vector span thickness is 140-180 mm,and the recommended range of 0.5 vector span thickness is 115-155 mm.The recommended range of thickness is 120mm-150 mm for 0.02 vector span and 100-130 mm for 0.1 vector span.(3)The influence of different opening forms on the mechanical properties of cylindrical shell and hyperbolic flat shell structures is studied.The results show that the opening rate of single hole has a greater effect on the residual stress of cylindrical shell structure,and a smaller effect on the residual stress of hyperbolic flat shell structure.When the vector to span ratio is0.3,0.4,0.5,the mechanical performance of the cylindrical shell structure with a single hole opening rate of 10% is 10% higher than that of the shell structure with a single hole opening rate of 20%.However,the difference of residual stress is small when the ratio of vector to span is 0.06,0.08 and 0.1.