Study On The Structure And Mechanical Properties Of Continuous Rigid-frame Bridge With Corrugated Steel Webs With Horizontal Backplane Cables

Based on the continuous rigid-frame bridge with corrugated steel webs on the horizontal floor,the structural space analysis model is established by using the Midas/Civil finite element program.The structural response characteristics are analyzed from the static and dynamic aspects.In the aspect of statics,the variation law of the internal force of the main beam is studied by using the corrugated steel web layout range,the main beam height,the beam bottom linear power,and the midspan thickness.The stiffness of the pier is studied by the geometric parameters of the pier.The impact of performance.In terms of dynamics,the effects of corrugated steel web layout range and pier height on the dynamic characteristics and seismic response of horizontal rigid steel bridges with corrugated steel webs are studied.The main researches are as follows:1)The stress and deflection of the continuous rigid-framed bridge with corrugated steel webs on the horizontal floor are analyzed for short-term and long-term conditions,and the structural bending capacity and the shear capacity of corrugated steel webs are checked.The results show that the deflection and tensile and compressive stresses in the construction stage meet the specifications.The deflection,compressive stress and normal section crack resistance of the use stage meet the specifications;the structural bending capacity and the shear capacity of the corrugated steel web meet the requirements of the specification.2)The main girder structure and mechanical properties and economics of the horizontal floor cable corrugated steel web continuous rigid frame bridge and ordinary continuous rigid frame bridge are analyzed.The analysis shows that in the state of bridge formation,the common continuous rigid frame bridge top and bottom plate The compressive stress curve changes more gently.The top and bottom compressive stress curves of the continuous rigid frame bridge of the corrugated steel web of the bottom plate are steep,and the stress at the steel-concrete joint is abrupt.It is worthy of attention,and the stress value of the nearby beam section is large,and the compressive stress The reserve is large;the horizontal rigid frame of the corrugated steel web of the horizontal floor is saved by 13.07% compared with the ordinary continuous rigid frame bridge,and the prestressed steel bundle is saved by 25.80%.3)Based on the height of the main beam,the thickness of the mid-span section,the shape of the bottom plate and the length of the corrugated steel web section,the internal force response characteristics of the horizontal rigid steel corrugated continuous rigid frame bridge are analyzed.The analysis shows that the layout of corrugated steel webs should be arranged from block No.1 to block No.1;the bending moment of the main beam root section decreases with the increase of the mid-span beam height,and the cross-section bending moment of the main girder spans with the cross The height of the middle beam increases and the value of the mid-span beam is 4.5m-5.5m.The bending moment of the root section of the main beam increases with the height of the root beam.The bending moment of the main beam cross-section cross-section along with the root beam The height is increased and decreased,the height of the root beam should be 10.5-11.5m;the line power of the beam should not exceed 2.0 times;the thickness of the midspan should not exceed 0.45 m.4)Analyze the influence of the geometric parameters of the pier(deck height,pier body cross-sectional area)on the main mechanical indexes of the structure for different pier types.The analysis shows that the height of the pier and the cross-section of the pier have less influence on the internal force and deformation of the main beam,and the internal force and deformation of the pier are significant.When the height of the pier is 20m-40 m,the thin-walled solid piers should be used.40m-80 m,rectangular hollow pier is suitable for pier height above 80 m.5)The self-vibration characteristics of the structure are analyzed.The tenth-order vibration modes of the structure are mainly vertical and side-bend,and no torsion has occurred.It shows that the structure has good torsional performance;the fifth-order vibration mode of the main beam is the main beam.The lateral bending and longitudinal floating,the sixth step is the positive symmetrical vertical bending of the main beam,indicating that the longitudinal stiffness of the main beam is larger than the lateral stiffness.6)Based on the analysis of the natural vibration characteristics of the structure,the influence of the layout range of the corrugated steel web and the height of the pier on the natural vibration characteristics of the structure is analyzed.The analysis shows that the influence of the layout of the corrugated steel web on the natural vibration characteristics of the structure is not obvious,and the growth rate of the structure frequency is within 11%.The variation of the pier height has a significant effect on the natural vibration frequency and vibration mode of the structure.7)Based on the seismic response analysis of the structure under earthquake action,the influence of the layout range of the corrugated steel web and the seismic response of the pier height on the structure is analyzed.The analysis shows that under the action of longitudinal earthquake,the root section of the main beam,the top and bottom section bending moments of the main beam are increased with the decrease of the corrugated steel web layout.Under the lateral earthquake,the left and right limbs of the main beam and The bending moment of the bottom of the pier is increased with the decrease of the layout of the corrugated steel web.Under the vertical earthquake,the bending moment and shearing force of the left and right limbs of the main beam are gradually increased with the decrease of the layout of the corrugated steel web..Under the action of longitudinal earthquake,the bending moment of the main beam side span 1/2,the main beam root and the top and bottom of the pier decreases with the increase of the pier height,and the change is gentle after 90 m.The shearing force of the main beam root and the pier bottom section shear force The increase of the height is reduced,and the axial force variation of the pier body decreases with the increase of the pier height.Under the lateral seismic action,the main beam side span 1/2,and the key moments of the main beam are increased with the height of the pier.Very large,the change is gentle after 90 m,except for the mid-span 1/2 section,the other key section shear forces decrease with the increase of the pier height,and the root beam torque change also decreases with the increase of the pier height;vertical Under the action of earthquake,the bending moment of each key section of the main beam increases greatly with the increase of the pier height.The shear force of the root section of the main beam decreases with the increase of the pier height,and the axial force variation of the pier body decreases with the increase of the pier height reduction.