Plate-truss combined steel truss girder bridge flutter and vibration restraining structure

Abstract

The invention discloses a plate-truss combined steel truss girder bridge flutter and vibration restraining structure. The late-truss combined steel truss girder bridge flutter and vibration restraining structure is arranged to be attached to bridge surface center anti-collision guardrail stand columns, used for increasing the flutter critical wind speed of a large-span combined steel truss girder bridge and characterized in that vertical center stable plates are installed on supporting seats of the two lines of bridge surface center anti-collision guardrail stand columns at intervals with the packing rate S along the center line of a bridge surface main beam, and S is within the range of 60%-80%; and the width of each center stable plate is equal to the separation distance L of every two adjacent center anti-collision guardrail stand columns, and the height D is within the range of 1-1.1 times H. According to the plate-truss combined steel truss girder bridge flutter and vibration restraining structure, through optimal selection of the packing rate and the heights of the center stable plates, the pneumatic layout of the structure starts from the source causing flutter of bridge flutter, the flutter derivative is changed to lower the pneumatic negative damping, so that flutter is transferred from single freedom degree torsional vibration to bending-torsion coupling vibration, accordingly, the flutter frequency of the main beam is lowered, and the flutter critical wind speed is increased; and material use is reduced to be 40% to the maximum, and under the precondition that structural safety of the plate-truss combined steel truss girder bridge is ensured, economical efficiency of the structure is improved.

Description

technical field [0001] The invention relates to the field of bridge wind engineering, in particular to the field of flutter control of long-span slab truss combined steel truss girder bridges. Background technique [0002] Plate truss combined with steel truss girder has high vertical stiffness and ventilation rate, and is convenient for transportation and construction, and is widely used in long-span bridges (such as figure 1 , figure 1 In a: A is the central anti-collision railing pole, B is the central anti-collision railing seat; figure 1 b is a side view of the prior art Unicom-type installation of the central stabilizing plate structure). However, due to the low natural frequency of the bridge due to its large span, the bridge is very sensitive to the wind, and the possibility of flutter instability is high under low wind speed. The flutter critical wind speeds of many long-span slab truss bridges combined with steel truss bridges at home and abroad cannot meet the ...

AI Technical Summary

Problems solved by technology

However, the use of the Unicom-type central stabilizing slab requires a large amount of steel and high cost; on the other hand, there is no relevant research on the interval setting of the central stabilizing slab of the plate-girder combined steel truss girder bridge

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