RU2550777C2 - Earthquake-proof bridge - Google Patents

Abstract

FIELD: construction.

SUBSTANCE: invention relates to earthquake protection of bridges. Earthquake-resistant bridge comprises spans, supports and associated seismic isolation devices, at least one of which is designed composite, comprising at least two series-connected elements. At least one of the elements is made flexible, malleable in the horizontal direction and provides a seismic isolation and damping of vibrations at relatively frequent calculated earthquakes attributable to the project (PE), and connection of elements is made sliding and includes friction-moving bolt connections from the package of steel sheets with oval openings, through which the high-strength bolts pass through.

EFFECT: increase of operational reliability and service life of the building, as well as improved efficiency of vibration damping of the bridge support, caused by seismic vibrations in any specified calculated range of the exposure level.

22 cl, 12 dwg

Description

Technical field

The invention relates to the field of transport construction, and more particularly to seismic protection of bridges, mainly railway.

State of the art

Currently, in the practice of earthquake-resistant construction, a multilevel approach to ensuring earthquake resistance has developed. According to this approach, the structure should guarantee a certain level of reliability and safety during earthquakes of various strengths and repeatability:

- maintain operational properties with relatively frequent, low impacts, called project earthquake (PZ),

- have a limited level of damage during moderate earthquakes (US),

- to ensure the safety of life of people and the main load-bearing structures in case of rare destructive earthquakes (maximum calculated earthquake or MRZ).

There are two possible ways to reduce seismic loads on bridge supports and ensure their earthquake resistance.

The first - the traditional way includes measures for the perception of existing seismic loads due to the development of cross-sections of supports and increase their reinforcement, reinforcement of support parts, etc. Such amplification works in case of earthquakes of any strength and, as the experience of past earthquakes shows [1, 2], ensures the absence of damage during the earth fault, moderate damage in the US, and the safety of spans and supports during the MRI. Such amplification is effective with a design seismicity of up to 8 points. With a seismicity of 9 or more points, the costs of anti-seismic amplification become very burdensome, reaching 35-40% of the cost of the structure.

With an estimated seismicity of 8 or more points, special methods of seismic protection of structures based on reducing the seismic loads themselves become effective.

Special methods include seismic suppression and seismic isolation methods. Traditional methods of seismic protection are described in the famous monographs of G.N. Kartsivadze [1] and G.S. Shestoperova [2].

Special methods of seismic protection are considered in the monographs of Skinner, Robinson and McVerry [3], the textbook of O.N. Eliseeva and A.M. Uzdin [4], as well as a review article by OA Savinova [5]. With respect to bridges, seismic isolation is reduced to the installation of seismic isolating devices in the form of flexible supporting parts. Abroad, the most widely used rubber support parts (ROCh) [6]. The use of such bearing parts by Maurer Söhns, FIP Industrialle, ALGA and several others is known. Figure 1 shows an example of a support with a rubber support part. Another example of the implementation of a flexible connection of superstructures with supports is shown in figure 2, the flexible supporting parts made of metal pipes or rods for AS USSR No. 1162886 "Supporting part of the structure" (IPC E01D 19/04).

A common seismic isolating device is ball bearing parts in which compliance is provided by gravitational forces, for example, the bearing part of the company Maurer Söhnes KR 20120022520 (IPC E01D 19/04). Such a support portion is shown in FIG.

Known solutions for special seismic protection have a common significant drawback.

Each of the known solutions protects the structure only from the effects of a certain level. For example, the aforementioned simple seismic isolation device using seismic isolating devices in the form of compliant support parts according to AS No. 1162886 (IPC E01D 19/04) works with a surface protection and, in part, ultrasonic scanning, and under the action of a water distribution system, it leads to large displacements of the span and its discharge from the supports. This fully applies to ROC. In the practice of earthquake-resistant construction, attempts have been made to create elements of seismic isolation that ensure their operation in case of strong earthquakes. To this end, the supporting parts were made of very large sizes. An example of such a ball bearing portion is shown in FIG. However, such solutions are completely unsuitable for railway bridges, since they worsen the operating conditions of the structure, since pliable supporting parts have large displacements under the operating load, which leads to disruption of the path on the bridge.

To ensure the protection of the bridge supports from MRZ, the so-called adaptive protection systems are used, which are blocked during operational loads, and are switched on during extreme loads. At the same time, additional reinforcement of the structure is required to counteract the PP and UZ. The simplest solution of this kind is seismic isolation devices made in the form of sliding support parts with friction-movable joints (FPS) on high-strength bolts. An example of such a solution, selected as a prototype, according to A.S. USSR No. 1106868 (IPC E01D 19/04) is presented in figure 5. The disadvantages of this solution include the ability to provide seismic resistance only in case of strong destructive earthquakes, during which the PPS slips and the load transmitted from the span to the support is limited. In the case of PZ, the device does not work and to compensate for their effects, it is necessary to strengthen the support by traditional methods.

SUMMARY OF THE INVENTION

The objective of the invention is to create a simple design seismic resistant bridge with the placement between the support and the span of such seismic isolation devices that can provide a damping mode for the supports at any load in a given design range.

The technical result achieved by the claimed invention is to increase the reliability of operation and the service life of the structure, as well as to increase the efficiency of damping the vibrations of the bridge supports caused by seismic vibrations in any exposure level in a given design range.

The claimed technical result is achieved by using an earthquake-resistant bridge, including spans, supports and seismic insulating devices connected to them, in which, unlike the prototype, at least one seismic insulating device is made integral and includes at least two elements, one of which is compliant in the horizontal direction and equipped with a friction-movable bolt connection, consisting of a package of metal sheets, at least one of which is rigidly connected to a compliant Seismic horizontal member and provided with an antifriction coating and oval holes through which pass high-strength bolts, to form a sliding pair, wherein the tension bolt is configured to limit the frictional force in the FFF not higher than the maximum permissible load on the support.

Moreover, in a preferred embodiment of the invention, the elements of the seismic isolation device are aligned, and the horizontal compliant elements are located at the bottom of the seismic isolation device and are connected to a support. Although, an embodiment of the invention is possible in which horizontally compliant elements are installed in the upper part of the device and connected to the span. You can also make both parts of at least one composite seismic isolation device compliant in the horizontal direction. In this case, the sliding pairs of the FPS, in a preferred embodiment of the invention, are made with an antifriction coating, with the possibility of eliminating slip during design earthquakes and operational loads.

In one preferred embodiment, the invention further comprises at least one seismic isolation device made as a reference, i.e. the span rests on it, with the possibility of perceiving the vertical load from the span. In one embodiment of the invention, one of the elements of at least one composite seismic isolation device can be rigid in the horizontal direction. It is advisable, and for bridges of large spans, it is necessary that the element of the composite seismic-insulating device rigid in the horizontal direction is made hinged, i.e. with the ability to rotate the end of the span relative to the support when skipping the load on the bridge. As an option for ensuring the articulation of the span connection with the support seismic isolation device, the element of the seismic isolation device is rigid in the horizontal direction and perceiving the support reaction made in the form of a cup support part.

To exclude, for example, vertical movements of the seismic isolation device dangerous for rails under load, both of its elements can be rigid in the vertical direction.

In another example embodiment of the invention, the horizontal compliant element of the seismic isolating device can be made in the form of a table of metal rods mounted in base plates. To increase the flexibility of the table, the rods can be pivotally connected to one of the base plates. The rods can be made, for example, of steel.

In another preferred embodiment of the invention, the seismic isolation device is made free of vertical loads. To this end, at least one independent support element is additionally installed in parallel with at least one seismic isolation device, connected to the support and the spans, the support element being rigid in the vertical direction and movable in the horizontal, and the span is equipped with supports transmitting the horizontal load on a horizontal seismic insulating element.

In this embodiment, to completely exclude the operation of the seismic isolating device for vertical loads, the seismic isolating device can be made in height less than the rigid in the vertical and horizontal movable support element, with the possibility of excluding the transfer of vertical load from the span to the seismic isolating device.

The claimed solution is most effective, in particular, if the operating mode of the span is implemented as a dynamic damper of support vibrations. For this, the seismic isolation device is made with rigidity C determined from the condition that it is possible to perform out-of-phase oscillations of the support and span when slipping at the lowest friction force F of the joint in the system of friction-movable joints and reduce the load on the support during an earthquake with calculated acceleration A, according to the formula

C = α · k ² · M µ (Nf, A),

where k is the partial vibrational frequency of the superstructure on the compliant supporting part (c),

α is a dimensionless coefficient depending on the dispersion of vibrational energy and the nature of the impact,

µ is an additional coefficient taking into account the friction force F in the FPS determined from the relation

F = nf

N is the compression force of the sheets of the package (N),

f is the coefficient of friction,

A - calculated acceleration (m / s ² ).

To exclude the work of the FPS bolts in bending, the package of metal sheets can be made of three groups of steel sheets equipped with oval holes: the first of which is rigidly connected to the compliant element and the large axis of the oval hole is oriented along possible movements of the span, the second is rigidly connected to the span and the third is made in the form of overlays connected to the sheets of the first two groups by a friction-movable bolt connection, and the steel sheets of the FPS are rigidly connected to this flexible moizoliruyuschim member and spans are coplanar.

To ensure a given scenario of damage accumulation in the structure, a compliant seismic insulating element can be made with less load bearing capacity for horizontal loads than a support, and a package of metal sheets is made in the form of a FPS cascade consisting of several series-connected friction-movable joints with different friction forces between elements joints and the size of the oval holes. In this case, the cascade of butt FPS includes at least three FPS, and the friction force in at least one of the FPS is less than the ultimate elastic load on the compliant seismic isolating element, the friction force in at least one other FPS of the cascade exceeds the elastic ultimate load on the compliant seismic isolating element, but less than the destructive load on this element and the estimated load on the support, the friction force of the third FPS is less than the destructive load on the compliant seismic isolating element, but more than the design load on the support and earlier than the breaking load on the support, and the oval holes in connection with less friction are made smaller.

The dimensions of the oval holes of the FPS of the cascade are made to enable the inclusion of cascades and to prevent overlapping of the last gap of the FPS.

In the case when dangerous movements of the rail track of the bridge occur during operational loads, the horizontal compliant support element is made with rigidity C determined from the condition that it is possible to exclude large displacements and stresses in the elements of the carriageway during operation, according to the formula:

C = Q / U _lim ,

where Q is the calculated operational load (N), U _lim is the maximum displacement of the span (m)

In order to reduce the displacements of the elastic element in the case of PZ and FPS in the case of MRI, dampers are additionally installed on supports in parallel with seismic isolating elements, with the possibility of moving in the direction of possible movements of the span.

Brief List of Drawings

The invention is illustrated by drawings, which depict:

figure 1. General view of the ROC (prior art).

figure 2. The support part is in the form of a flexible support table (prior art).

figure 3. Spherical bearing part (prior art).

figure 4. Spherical support part of the bridge (Benicia_Martines Bridge), providing displacement of the span during MRZ (prior art)

figure 5. Sliding support part with FPS on high-strength bolts (prototype);

Fig.6. Scheme of supporting the span on a support when using the hinged support part of a seismic isolating device

Fig.7. Scheme of supporting the span on a support using a glass supporting part of a seismic isolating device

Fig.8. Scheme of supporting the span on a support when using a vertical support of a seismic isolating device

Fig.9. The connection diagram of the racks with the lower and upper plates of the lower element of the supporting device

figure 10. Separation of vertical and horizontal loads between a composite seismic isolating device and a movable supporting part

11. Scheme of the operation of lap FPS

Fig.12. Connection diagram using FPS and butt pads, where a) is a view from the side of the pads, b) is a side view.

It should be noted that the accompanying figures 6-12 illustrate only selective variants of a possible embodiment of the invention and cannot be considered as limitations on the content of the invention, which includes other embodiments.

The implementation of the invention

As follows from the drawings shown in Fig.6-12, the seismic isolation device is made composite, including two series-connected elements. At least one of the elements is flexible and provides seismic isolation and seismic suppression of vibrations during relatively frequent design earthquakes related to design (PZ), and the connection of the elements is made sliding and includes friction-movable bolted joints from a package of steel sheets with oval holes through which high-strength passed bolts.

The invention is illustrated by drawings (6, 7). An earthquake-resistant bridge, includes spans 1 and supports 5. Between them there is a seismic isolating device consisting of two series-connected elements, which in the considered embodiment is a reference. The lower seismic isolating element 6 is compliant in the horizontal direction, and the upper element 2 is rigid in the horizontal direction. In Fig.6, the upper element 2 is made in the form of a pivotally-fixed supporting part, and in Fig.7 - in the form of a glass supporting part. In both versions, the upper elements 2 provide the possibility of rotation of the span and transfer the horizontal load to the lower element 6. The upper element 2 of the device in Fig. 6 includes the lower 10 and upper 9 balancers, and in Fig. 7 includes a glass with filling 11. Otherwise, both options are identical. The upper and lower elements have supporting sheets 4, between which an anti-friction coating 3 is located. The sheets are interconnected by a friction-movable joint (FPS) 7 in which high-strength bolts connect the supporting sheets of the upper and lower elements of the seismic isolation device.

The device operates as follows. With relatively frequent earthquakes with a frequency of once every 200-500 years, friction in the PPS is not overcome, and the connection works as a hard one. At the same time, the malleable element of the seismic isolating device provides seismic isolation, and with appropriate tuning in terms of stiffness and seismic suppression of the support vibrations. In rare strong earthquakes, slippage occurs in the FPS, and loads exceeding the friction force in the FPS cannot be transferred to the support from the span. In this case, the tension of the bolts and the processing of the FPS surfaces are made so that the friction force in the FPS does not exceed the maximum allowable load on the support. Thus, there is a decrease in loads both in case of PP and in case of MPE.

To exclude vertical movements of the span under load, it is unacceptable to use pliable support parts in the vertical direction, for example, RC. Thus, in order to eliminate vertical compliance of the proposed bearing device, the upper and lower elements are rigid in the vertical direction. At the same time, it is advisable to use the usual supporting part as the upper element, and the lower element is made of horizontal flexible steel pipes 12 (Fig. 8).

To increase the flexibility of racks made of steel pipes or rods, the latter should be connected to one of the sheets articulated (Fig.9). To do this, the rack of steel pipe 12 is simply inserted into the groove 13 of the upper or lower base plate. The other end of the rack, at the same time, is embedded in the base plate.

In the considered embodiment of the invention, the racks of the table perceive vertical and horizontal loads from the span. At the same time, the racks may lose stability and horizontal bearing capacity. In order to increase the horizontal bearing capacity of the compliant element of the seismic isolating device, an additional supporting element is installed in the vertical direction and horizontally movable in the horizontal direction with the seismic isolating device. Moreover, the seismic isolation device is made in height smaller than the rigid support element and does not absorb vertical load, and the span structure is equipped with stops that transmit horizontal load to the seismic isolation device.

To increase the bearing capacity of the compliant element of the seismic isolation device under the action of longitudinal load, another embodiment of the invention is possible in which, between the span 1 and the support 5, a support element 14 is installed in parallel with the compliant seismic isolation element 6, which is a conventional movable supporting part. The upper sheet of the compliant member 4 with an anti-friction coating is connected to the additional sheet 15 by FPS 7. In this case, the sheets 4 and 15 with the anti-friction coating and FPS 7 form the upper sliding element. Stops 16 are installed on the span 1, which are in contact with the additional sheet 15 and have the freedom of vertical movements relative to the sheet 15. Moreover, the compliant element with the sliding element has a height h less than the height of the movable supporting part N. This eliminates the transfer of vertical load from the span on a malleable element. In this embodiment, the vertical load is fully absorbed by the movable support portion. This increases the bearing capacity of the compliant element under the action of horizontal load. During operational loads (braking of rolling stock, transverse impacts of vehicles), as well as under the action of a horizontal beam, horizontal loads are transmitted from the span structure (1) to the support 5 through the stops 16 and the flexible element 6. In this case, the dynamic loads on the support are reduced due to the shock absorbing effect compliant element. When MRI is moving in the FPS and the peak load on the support is limited by the friction force in the FPS. Thus, the design loads are reduced both under the action of the PP and under the action of the MRZ.

An important feature of another example implementation is the implementation of a compliant element with a certain stiffness. In a well-known solution according to A.S. USSR MKI E01D 19/04 No. 1162886 “Supporting part of the structure”, the rigidity of the compliant supporting part is selected from the condition

where k is the natural frequency of vibrations of the structure (support),

M is the mass of the span,

α - coefficient, the value of which depends on the damping and the relative mass of the span.

The values of α are detailed by the authors in the Instruction [7].

The use of this formula optimizes the reduction of seismic loads during PZ, but does not provide quenching during MRI, since in the known solution the own period of support vibrations changes during damage accumulation in it.

In the proposed solution, the absence of damage to the support during the PP is ensured by the slip of the span according to the FPS and additional blanking during the PP is impractical. In this regard, the malleable element is performed with stiffness determined from formula (2)

where k is the partial vibrational frequency of the superstructure on the compliant supporting part (1 / c),

α is a coefficient depending on the dispersion of vibrational energy and the nature of the impact (see AS USSR E01D 1162886),

µ <1 is an additional coefficient taking into account the friction force in the FPS F = Nf and the level of the calculated impact A.

Due to the selection of the coefficient µ, the antiphase oscillations of the support and the span under exposure with peak accelerations equal to A.

Another embodiment of the invention is aimed at improving the operation of a seismic isolating device by optimizing the design of the FPS. In the known solutions, the FPS of the parts of the structures "overlap" is used, as shown in Fig.5. In the process of moving, sliding occurs on the contact of the bolt head and the connection sheet with the corresponding skew of the bolt 17 (Fig. 11). This leads to deformation of the bolts and instability of the connection [8]. In order to increase the reliability of the friction-movable bolt joint during large movements, the joint in the claimed invention is made in the form of three groups of steel sheets: the first group of sheets is rigidly connected to a compliant element of the supporting part, the second is rigidly connected to the span, and the third, in the form of overlays connected to the first two friction-movable bolt joints. In the considered embodiment, a steel sheet 19 with oval openings located along the possible movements of the span is rigidly attached to the upper plate 18 of the compliant element. In the same plane with it is another sheet 20, rigidly connected to the span and also having oval openings. The sheets are interconnected by linings 21, through which high-strength bolts 17 are passed. The connection with the plates in one of the sheets is made with less friction (due to surface treatment or tension of the bolts) than in connection with another sheet, and the oval holes in connection with a smaller the friction is made smaller (see Fig. 12 a) and b), where a is the size of the holes with a lower coefficient of friction (f _Tr ), A - with a larger (F _Tr )). Thus, a malleable element is connected to the span using a butt FPS.

In the process of the earthquake, initially the friction in the FPS is not overcome, and the load from the span is transmitted to the compliant element (Fig. 12 a) and b)). With the growth of mutual displacements, a smaller friction force begins to be overcome. In this case, the sheet “slips” out of the plates, and the bolt is not deformed. This movement will occur until the sheet rests against the edge of the oval hole in the bolt. After that, the movement of the second sheet relative to the overlays will begin.

The proposed design also allows to overcome the disadvantage of the known structures, which consists in the adverse effects on the bridge supports of high stresses in the rail track under railway load. In order to exclude large displacements and stresses in the elements of the carriageway during normal operation, compliant elements are performed with stiffness determined by the formula

where Q is the calculated operational load, and U _lim is the maximum displacement of the span.

см. Здесь L - величина пролета в метрах. Исследования авторов, выполненные при обосновании применимости заявляемого решения, показали, что можно принимать $$U_{\lim }=\sqrt{L}$$

, где смещение получается в см, а пролет задается в м.In accordance with the JV Bridges and Pipes, the value of U _{lim is} taken equal to $$0.5\sqrt{L}$$

see. Here L is the span in meters. Studies of the authors, carried out to justify the applicability of the proposed solution, showed that you can take $$U_{\lim }=\sqrt{L}$$

, where the displacement is obtained in cm, and the span is specified in m.

In another embodiment of the invention, it is provided to install dampers in parallel with support elements on supports that are capable of moving in the direction of possible shifts of vertical support elements that are rigid in vertical direction, which allows to reduce displacements in the PPS during MRS and to reduce the forces in the compliant element in case of PP.

Thus, it is obvious that the use of a composite seismic isolating device, one of the elements of which is a horizontal compliant element equipped with FPS, in combination with the second elements implemented in different ways, allows to increase the reliability of operation and the service life of the structure, as well as significantly increase the efficiency of quenching seismic vibrations of the bridge supports in any given design range.

Literature

1. Kartsivadze G.N. Seismic Resistance of Road Artificial Structures / M., Transport, 1974, 260 p.

2. Kuznetsova I.O., Uzdin A.M. Modern problems of seismic resistance of bridges. (Based on materials of the 12th European Conference. London. September, 2002), Earthquake-resistant construction, No. 4, pp. 63-68

3. Skiner R.I., Robinon W.H., McVerry G.H. An introduction to seismic isolation. New Zealand John Wiley & Sons. 1993, 353 p.

4. Eliseev O.H., Uzdin A.M. Earthquake Engineering, PVISU, 1997, 371 pp.

5. Savinov O.A. Seismic isolation of structures (concept, device principle, calculation features) // Selected articles and reports "Dynamic problems of construction equipment", St. Petersburg, Izd. VNIIG them. B.E. Vedeneeva, 1993, p. 155-178

6. Kelly J.M. Earthquake resistant design with rubber. Springer 1997, 243 p.

7. Instructions for assessing the earthquake resistance of operated bridges on a network of railways and roads (in the territory of the Turkmen SSR). - Ashgabat: Ylym, 1988 .-- 106 p.

8. Eliseev O.N., Kuznetsova I.O., Nikitin A.A., Pavlov V.E., Simkin A.Yu., Uzdin A.M. Elements of the theory of friction, calculation and technology of the use of friction-mobile joints. St. Petersburg, VITU, 2001, 75 s

Claims (22)

1. An earthquake-resistant bridge, including spans, supports and seismic insulating devices connected to them, characterized in that at least one seismic insulating device is made integral and includes at least two elements, one of which is compliant in the horizontal direction and is equipped with a friction-movable bolted connection consisting of a package of metal sheets, at least one of which is rigidly connected to a horizontally compliant seismic isolating element and is equipped with antifreeze with an iktion coating and oval holes through which high-strength bolts are passed, with the possibility of forming a sliding pair, and the tension of the bolts is made so that the friction force in the FPS can be limited to no higher than the maximum permissible load on the support. 2. The earthquake-resistant bridge according to claim 1, characterized in that the sliding pairs of the FPS are made with an anti-friction coating, with the possibility of eliminating slipping during design earthquakes and operational loads. 3. The earthquake-resistant bridge according to claim 1, characterized in that the elements of the composite seismic isolating device are aligned, and the compliant elements in the horizontal direction are connected to the support. 4. The earthquake-resistant bridge according to claim 1, characterized in that the elements of the composite seismic isolation device are aligned, and the compliant elements in the horizontal direction are connected to the span. 5. The earthquake-resistant bridge according to claim 1, characterized in that at least one composite seismic insulating device both elements are compliant in the horizontal direction. 6. The earthquake-resistant bridge according to claim 1, 3, characterized in that one of the elements of at least one composite seismic isolation device is made rigid in the horizontal direction. 7. The earthquake-resistant bridge according to claim 1, characterized in that it further comprises at least one seismic isolation device made as a support, with the possibility of perceiving the vertical load from the span. 8. The earthquake-resistant bridge according to claim 6, characterized in that the element of the composite seismic isolating device is rigid in the horizontal direction is hinged. 9. The earthquake-resistant bridge according to claim 6, characterized in that the element of the composite seismic isolating device is rigid in the horizontal direction in the form of a cup support part, with the possibility of perception of the support reaction. 10. An earthquake-resistant bridge according to any one of claims 1-5, 7-9, characterized in that both elements of the seismic isolating device are rigid in the vertical direction with the possibility of eliminating vertical movements of the seismic isolating device under load. 11. The earthquake-resistant bridge according to claim 10, characterized in that the horizontal compliant element of the seismic isolating device is made in the form of a table of metal rods fixed in base plates. 12. The earthquake-resistant bridge according to claim 11, characterized in that the rods are pivotally connected to one of the support plates. 13. The earthquake-resistant bridge according to claim 11 or 12, characterized in that the rods are made of steel. 14. The earthquake-resistant bridge according to claim 1, characterized in that at least one independent support element is connected in parallel with at least one seismic isolation device, connected to the support and the spans, the support element being rigid in the vertical direction and movable in the horizontal and the span is equipped with stops that transmit the horizontal load to the horizontal seismically insulating element. 15. The earthquake-resistant bridge according to 14, characterized in that the seismic isolation device is made in height less than the rigid in the vertical and horizontal movable support element, with the possibility of excluding the transfer of vertical load from the span to the seismic isolation device. 16. An earthquake-resistant bridge according to any one of claims 1 to 5, 7-9, 11, 12, 14 or 15, characterized in that the seismic isolating device is made with rigidity C, determined from the condition that it is possible to perform antiphase vibrations of the support and the span when slipping with the smallest friction force F of the joint in the system of friction-movable joints and reduction of the load on the support during an earthquake with a calculated acceleration A, according to the formula
C = α · k ² · M µ (Nf, A),
where k is the partial vibrational frequency of the superstructure on the compliant supporting part (s),
α is a dimensionless coefficient depending on the dispersion of vibrational energy and the nature of the impact,
µ is an additional coefficient taking into account the friction force F in the FPS, determined from the relation
F = nf
N is the compression force of the sheets of the package (N),
f is the coefficient of friction,
A - calculated acceleration (m / s ² ). 17. The earthquake-resistant bridge according to claim 1, characterized in that the package of metal sheets includes three groups of steel sheets equipped with oval openings: the first of which is rigidly connected to the compliant element and the oval is elongated along possible movements of the span, the second is rigidly connected to the span, and the third is made in the form of overlays connected to the sheets of the first two groups by a friction-movable bolt connection, and the FPS steel sheets rigidly connected to a compliant seismic isolating element and a span HAND, arranged in one plane. 18. The earthquake-resistant bridge according to claim 17, characterized in that the compliant seismic isolating element is made with lower horizontal load bearing capacity than the support, and the package of metal sheets is made in the form of a FPS cascade consisting of several series-connected friction-movable joints with different strengths friction between the connection elements and the size of the oval holes. 19. The earthquake-resistant bridge according to claim 18, characterized in that the cascade of butt FPS includes at least three FPS, and the friction force in at least one of the FPS is less than the ultimate elastic load on a compliant seismic insulating element, the friction force is at least one more FPS of the cascade exceeds the elastic ultimate load on the compliant seismic isolating element, but is less than the breaking load on this element and the calculated load on the support, the friction force of the third FPS is less than the breaking load on the flexible seismic isolating element, n greater computational load on the support and a lower failure load on a support, wherein the oval holes in combination with less friction made smaller 20. An earthquake-resistant bridge according to any one of paragraphs.17-19, characterized in that the dimensions of the oval openings of the FPS are made to enable cascades and prevent overlapping of the last gap of the FPS. 21. An earthquake-resistant bridge according to any one of claims 1-5, 7-9, 11, 14, 15 or 17-19, characterized in that the horizontal compliant seismic insulating element is made with a rigidity C, determined from the condition that it is possible to exclude large movements and stresses in the elements of the carriageway during operation, according to the formula
C = Q / U _lim ,
where Q is the calculated operational load (N), and U _lim is the maximum displacement of the span (m). 22. An earthquake-resistant bridge according to any one of claims 1-5, 7-9, 11, 12 or 14 or 17-19, characterized in that dampers are additionally mounted on supports in parallel with seismic isolating elements with the ability to move in the direction of possible movements of the span.

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