SU1214815A1 - Apparatus for damping oscillation of split span structures of bridges - Google Patents

Description

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The invention relates to bridge construction, in particular, to structures of damping devices used to dampen vibrations of bridge spans.

The purpose of the invention is to provide an adjustable damping of the span structures.

FIG. 1 schematically shows the proposed device, a general view; in fig. 2 is a section A-A in FIG. 1; in fig. 3 shows the node I in FIG. 2

The device for damping vibrations of bridge spans contains shock absorbers, each of which includes paired plates 1 rigidly fastened with one end between themselves and the wall of the main beam of one of the adjacent span structures 2 with bolts 3, and the other ends with friction pads 4 covering the wall of the main beam the second, adjacent to the first, superstructure 5, spring-loaded pressure elements 6.

The ends of the paired plates on the placement side of the pressure elements have pairs of wedges 7, the vertices of which converge at the location of the spring-loaded pressure elements 6. To ensure the displacements of the adjacent ends of the adjacent spans 2 and 5, the holes of the spring-loaded elements 6 , and in friction pads 4, in paired plates 1 and counter wedges x 7 fixedly mounted on plates 1 there are oval holes 8 through which spring-loaded pressure elements 6 are passed. Between the pairs there is a wedge s 7 and nuts pressers 6 are the second pair of wedges 7 as washers 9 having a contact surface which is identical with the first pair of wedges, and the other (on the side of the head and nut pressers 6) - flat. The diameter of the hole of the washer 9 corresponds to the size of the pressure elements 6,

The device works as follows.

Under the influence of dynamic loads, oscillations of adjacent flying structures 2 and 5 occur. The paired plates 1 fixed by bolts 3 on the flying structure 2 move relative to the wall of the main beam of the flying structure 5.

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Spring-loaded springs 10 pressure elements 6 presses the paired plates 1 against the wall of the main beam of the superstructure 5, due to the presence

5 pairs of wedges 7, washers 9, with variable force. Moreover, the force of pressing and, accordingly, the effect of damping vibrations of adjacent spans 2 and 5 will be the higher, the more you move 0 or spans. The possibility of displacement of the paired plates fixed on the span 2 relative to the adjacent span 5, is provided by the presence of friction pads 4, twin plates 1 and pairs of wedges 7 in the friction pads 4, oval holes 8 under the pressure elements 6, the friction pads 4 between the wall of the span 5 and paired

20 plates 1 increase the coefficient of friction of mutually moving surfaces, increasing the efficiency of damping of the bridge span structures.

25 In the wedge technique is widespread. The most common slopes are 1/100 wedges; 1/40; 1/30; less often - 1/24; 1/2 (3. Along with its direct purpose, the wedge is used to obtain variable forces during reciprocating movements. The proposed device uses pairs of wedges whose vertices converge at the place of application of force (location of the pressure element). The washers 9 from the side of the wedges have a slope that is identical to the bias of the wedges, and from the side of the nuts of the pressure elements - a flat surface.

Due to this solution, an increase in the reciprocating movement of the ends of the adjacent superstructures is accompanied by an increase in the pressing forces of the paired plates 1 against the wall of the superstructure 5, an increase in friction losses, i.e. automatic increase in the damping capacity of the device, regardless of the direction of mutual movements

adjacent span buildings 50

In the walls of the beams of adjacent spans, there are openings for high-strength bolts to merge split spans into non-split ones during their installation or mounting. Therefore, these holes and are used unchanged to avoid weakening of the walls, And for providing

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chenii mobility of the ends of adjacent spans 2 and 5, in friction pads A, paired plates

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1, oval holes 8 are made through which spring-loaded pressure elements 6 are passed.

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Compiled by V. Zubkov Editor Y. Sereda Tekhred L. Micket Proofreader E. Sirohman.

Order 864/42

Circulation 515

VNIIPI USSR State Committee

for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5

Branch PPP Patent, Uzhgorod, st. Design, And

fpae.S

.Subscription

Claims (1)

DEVICE FOR EXTINGUISHING VIBRATIONS OF CUT TO BRIDGES, including shock absorbers placed between adjacent spans, each of which contains paired plates with holes, rigidly fastened at one end to the wall of the main beam of one of the adjacent spans, friction with spacer holes placed between the other with plate openings and a wall of the main beam of the second having openings. adjacent to the first span, spring-loaded pressure devices, passed through the combined holes in the pair of plates, friction linings and the wall of the main beam, characterized in that, in order to provide adjustable damping of the spans, each pressure device is equipped with at least two pairs of wedges, interacting with each other by inclined faces and located within each pair with a gap relative to one another to pass the body of the pressure tool, and the bottom of the pair of wedges is rigidly mounted on the corresponding plate, and the other is placed under the spring-loaded end of the pressing device, while the combined holes in the pair of plates for the passage of the pressing device are made oval and corresponding in size to the gaps between the wedges, and the holes in the wall of the second adjacent to the first span are made round.