Double-column type pier structure system with multi-stage anti-seismic protection and self-resetting functions

Abstract

The invention discloses a double-column type pier structure system with multistage anti-seismic protection and self-resetting functions, and belongs to the technical field of bridge engineering anti-seismic design and toughness improvement. The double-column type pier comprises two concrete filled steel tube section columns, a connecting beam is arranged between the two concrete filled steel tube section columns, and the connecting beam comprises a concrete cast-in-place connecting beam and a steel section prefabricated connecting beam. The steel section prefabricated coupling beam comprises embedded sections, the embedded sections on the two sides are rotationally connected, and the embedded sections are connected through a connecting plate with an energy dissipation structure and a steel strand to form an overall structure capable of dissipating energy and achieving self-resetting. Unbonded prestressed tendons and energy-consuming steel bars for self-resetting are arranged in the concrete-filled steel tube section column in a penetrating manner so as to adapt to deformation of a pier body when joints between sections of the concrete-filled steel tube section column swing. The adaptability and restoring force of the bridge pier under different seismic intensities can be enhanced, the structural stability and integrity are ensured, meanwhile, the bridge pier structure and the connecting mode are optimized, and rapid repairing and function recovery after an earthquake are achieved.

Description

Technical Field

[0001] The present invention belongs to the technical field of seismic design and toughness improvement of bridge engineering, and specifically relates to a double-column pier structure system with multi-level seismic protection and self-resetting functions. Background Art

[0002] Globally, earthquake activity is frequent and unpredictable, posing a serious threat to the safety and stability of bridge structures. As a key transportation hub in post-earthquake emergency rescue operations, the importance of seismic design of bridges is particularly prominent, which is directly related to the efficiency of rescue and the smooth progress of post-disaster recovery work. The strong impact force caused by earthquakes often causes serious plastic deformation of bridge piers or even overall collapse, posing a major threat to the bearing capacity of bridges and the maintenance of traffic functions. Therefore, enhancing the seismic performance of bridge piers has become a core issue and urgent need in the field of bridge engineering research.

[0003] Traditional self-resetting structures often use prestressed tendons, rubber materials, spring devices, and shape memory alloys to construct reset mechanisms, and combine friction energy dissipation, metal yield energy dissipation, viscoelastic damping energy dissipation, and magnetorheological energy dissipation elements to ensure the recoverability of the structure under earthquake action. However, such structures face multiple challenges in actual engineering applications. On the one hand, most structures are designed as two-stage or three-stage seismic fortification systems, and their seismic fortification capabilities are relatively limited. When encountering strong earthquakes, such structures are difficult to fully absorb and effectively disperse seismic energy, which may cause serious damage to the structure or even overall collapse, which will seriously affect the ability of key transportation facilities such as bridges to recover and use after the earthquake, and pose a potential threat to the connectivity of the transportation network and the smooth implementation of post-earthquake rescue work. On the other hand, some traditional self-resetting structures are relatively complex in structural design, and cumbersome tensioning and prestressing processes are required during construction and installation, which not only increases the difficulty and cost of construction, but also may affect the long-term stability and reliability of the structure. In addition, after experiencing strong earthquakes, the performance of the energy-consuming components of these structures is prone to attenuation, and the replacement and maintenance costs of damaged components are high, which brings additional burdens to the operation and maintenance of bridges. Therefore, the academic and bridge engineering communities are currently working actively to develop self-righting structures that can fully consume energy, are easy to repair, and are convenient to construct and install, in order to meet the above challenges.

[0004] In view of the limitations of traditional self-resetting structures in bridge seismic applications, the present invention proposes a new solution: a self-resetting double-column pier system with multi-stage seismic fortification. The system introduces a multi-stage seismic strategy, which enables the piers to gradually activate the corresponding seismic mechanisms under different earthquake intensities, effectively enhancing their adaptability and recovery capabilities. At the same time, the system adopts a graded energy dissipation mechanism combined with a self-resetting system to ensure that seismic energy can be efficiently absorbed, dispersed and released when an earthquake occurs, maintaining the stability and integrity of the structure. In addition, by optimizing the structure and connection method of the piers, the construction process is simplified, the construction efficiency is improved, and rapid repair and resumption of use after the earthquake are achieved, which significantly improves the overall seismic performance and safety of the bridge. Summary of the invention

[0005] In view of the above problems existing in the prior art, the purpose of the present invention is to provide a multi-stage seismic fortification self-resetting double-column bridge pier system. The system aims to enhance the adaptability and resilience of the bridge piers under different earthquake intensities, ensure structural stability and integrity, optimize the bridge pier structure and connection method, achieve rapid post-earthquake repair and functional recovery, and provide an efficient and reliable solution for improving the overall seismic performance and safety of the bridge.

[0006] The present invention provides the following technical solutions: a double-column pier structure system with multi-level earthquake protection and self-resetting functions, the double-column pier comprising two steel tube concrete segmented columns arranged between the bridge abutment and the cap beam, a connecting beam being arranged between the two steel tube concrete segmented columns, the connecting beam comprising a concrete cast-in-place connecting beam arranged on the steel tube concrete segmented column and a steel segment prefabricated connecting beam connecting the concrete cast-in-place connecting beams on both sides; the steel segment prefabricated connecting beam comprising an embedded section fixedly connected to the concrete cast-in-place connecting beam, the embedded sections on both sides being rotatably connected, and connected to form an integral structure capable of consuming energy and self-resetting through a connecting plate and a steel strand provided with an energy-absorbing structure, so as to adapt to the overall deformation of the pier body; the steel tube concrete segmented column is provided with unbonded prestressed tendons and energy-absorbing steel bars for self-resetting, so as to adapt to the deformation of the pier body when the joints between the steel tube concrete segmented columns swing.

[0007] Furthermore, the embedded sections on both sides are connected via a middle extension section, and both ends of the middle extension section are rotatably connected to the embedded sections via vertically arranged lateral connection plates.

[0008] Furthermore, the embedded section and the middle extension section are fastened to the embedded section via a transversely arranged connecting plate; the steel strands pass through the middle extension section and the embedded sections on both sides, and are tensioned and fixed to ensure the stability of the overall structure of the steel section prefabricated connecting beam.

[0009] Furthermore, a curved energy dissipation section is provided on the connecting plate.

[0010] Furthermore, the unbonded prestressed tendons are built into the steel tube concrete segmental column, and the two ends thereof pass through the pedestal and the cap beam respectively, and are fixed after being tensioned by prestressed anchors.

[0011] Furthermore, each segment of the steel tube concrete segmented column is penetrated with energy-absorbing steel bars, and the energy-absorbing steel bars in adjacent segments are connected in sequence; the energy-absorbing steel bars in the segments at both ends extend to the pedestal and the cap beam respectively.

[0012] Furthermore, steel rods are welded at the connections of the outer edges of adjacent segments in the steel tube concrete segmented column.

[0013] The working principle of the system of the present invention is as follows:

[0014] The system of the present invention uses the unbonded prestressed tendons and steel strands to jointly play the role of structural self-reset; at the same time, the system also incorporates components such as energy-absorbing steel bars, steel bars, and connecting beam connection plates to provide graded energy dissipation under earthquakes. When encountering earthquakes of different intensities, the various components in the system can dissipate seismic energy in a graded and coordinated manner, showing unique performance, as follows:

[0015] During minor earthquakes, i.e., frequent earthquakes, bridge piers and coupling beams are mainly in an elastic response state, and their seismic performance mainly depends on the elastic properties of the material itself. Under the design earthquake, due to the prestressing effect between the pier segments, the steel rods are not sheared off, and the segments are still closed, and the pier body (steel tube concrete segmental column) is mainly deformed as a whole; the connecting beam between the two piers undergoes relative deformation to adapt to the overall deformation of the pier body, and the various components of the steel prefabricated coupling beam play a role, among which the curved connecting plate and the lateral connecting plate dissipate the seismic energy by means of friction and pressure bearing mechanism. Under rare earthquakes, the steel rods of the steel tube concrete segmental column are sheared off, and the joints between the segments swing to adapt to the deformation of the seismic pier body. At this time, in addition to the curved connecting plate and the lateral connecting plate of the steel prefabricated coupling beam playing the role of energy dissipation and self-reset, the energy-absorbing steel bars between the segmental columns also enter plasticity due to the swinging and opening, and cooperate with the energy-absorbing elements in the steel segment prefabricated coupling beam to achieve the maximum utilization of energy consumption. At the same time, the prestressed steel bars / steel strands in the pier body are stretched to provide the pier body with self-reset capability. In this double-column pier system, under each stage of earthquake-resistant fortification, the energy-absorbing elements and self-resetting elements of the coupling beam and segmental pier columns can operate individually or in coordination, so that the overall structural damage of the pier is reduced to a minimum. After the earthquake-resistant protection is over, the pier can automatically return to its initial state by replacing the damaged components.

[0016] By adopting the above technology, compared with the prior art, the beneficial effects of the present invention are as follows:

[0017] 1) The double-column bridge pier construction of the present invention adopts segment prefabrication and assembly technology, which not only simplifies the on-site construction process and improves the construction efficiency, but also significantly enhances the overall quality and durability of the bridge pier;

[0018] 2) The performance-based seismic design of the bridge pier system of the present invention achieves fine control of the bridge pier structure under different earthquake levels through reasonable seismic grade classification and performance target setting;

[0019] 3) The bridge pier system of the present invention introduces multiple energy-absorbing components and a self-resetting mechanism to reduce the residual deformation of the structure, improve the seismic toughness of the bridge pier, and ensure its rapid recovery ability after an earthquake. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 : A schematic diagram of the overall structure of a double-column pier structure system with multi-level earthquake protection and self-reset function;

[0021] Figure 2 : Schematic diagram of the connection of steel tube concrete segmental columns under rare earthquakes;

[0022] Figure 3 : Overall schematic diagram of steel segment prefabricated coupling beam;

[0023] Figure 4 : Schematic diagram of the structure of the connection part of the steel segment prefabricated coupling beam;

[0024] Figure 5 : Schematic diagram of the structure of the embedded sections at both ends;

[0025] Figure 6 : Schematic diagram of the structure of the middle extension section;

[0026] Figure 7 : Schematic diagram of the structure of the lateral connecting plate;

[0027] Figure 8 : Schematic diagram of the structure of the connecting plate. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments of the specification. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0029] On the contrary, the present invention covers any substitution, modification, equivalent method and scheme made on the essence and scope of the present invention as defined by the claims. Further, in order to make the public have a better understanding of the present invention, some specific details are described in detail in the detailed description of the present invention below. Those skilled in the art can fully understand the present invention without the description of these details.

[0030] like Figure 1As shown, a double-column bridge pier structure system with multi-level earthquake protection and self-reset function of the present invention includes a steel tube concrete segment column 1, a cap 2, a cap beam 3 and a coupling beam. Among them, the coupling beam includes a concrete cast-in-place coupling beam 4 and a steel segment prefabricated coupling beam 5. The pier components are prefabricated in the factory and assembled on site.

[0031] Specifically, the cast-in-place concrete coupling beam 4 is prefabricated and installed in sections. When one end of each section is prefabricated, an energy-absorbing steel bar 7 is embedded. The steel tube concrete section column 1 and the cast-in-place concrete coupling beam 4 are cast as a whole, and the two end pre-embedded sections 52 of the steel section prefabricated coupling beam 5 are embedded in advance. Figure 2 As shown, PVC channels are reserved on the central axis of the cast-in-place concrete connecting beam 4, the cap beam 3 and the pedestal 2, and energy-absorbing steel bar channels are reserved around the pier diameters of the cap beam 3 and the pedestal 2 and embedded with corrugated pipes to facilitate the subsequent installation and fixation of the unbonded prestressed tendons 6 and the energy-absorbing steel bars 7.

[0032] Specifically, Figure 3 As shown, the steel segment prefabricated connecting beam 5 includes a middle extension section 51 and two end embedded sections 52. Figure 4 Schematic diagram of the connection part structure, the middle extension section 51 and the upper and lower flanges of the embedded sections 52 at both ends are connected by high-strength bolts 10 using a bent connecting plate 53, and the web is connected by high-strength bolts 10 and pins 11 using lateral connecting plates 54.

[0033] Specifically, Figure 5 As shown, the embedded sections 52 at both ends include embedded steel plates 521, studs 12, I-beams 14 and fixing plates 15, wherein the various components are connected as a whole through the fixing plates 15, and play a role in limiting the position of the steel strands 55. Furthermore, the web connection area of ​​the I-beam 14 is designed with an annular perforation 13, the flange plate connection adopts a circular perforation 16, and the fixing plates 15 are reserved for the steel strands 55. During prefabrication, the studs 12 and the embedded steel plates 521 are embedded in the flanks of the concrete cast-in-place coupling beam 4.

[0034] Specifically, Figure 6 As shown, the middle extension section 51 includes an I-beam 14 and a fixing plate 15. Similarly, the web connection portion of the I-beam is designed with an annular through hole 13, and the connection portion of the flange plate is configured with a circular through hole 16. In addition, a circular through hole 16 is also reserved on the fixing plate 15 for the passage of the steel strand.

[0035] Specifically, Figure 7 As shown, annular holes are designed at both ends of the lateral connecting plate 54, and the annular holes include high-strength bolt holes 131 and pin holes 132. After installation, under the action of an earthquake, this design allows relative rotation between the structures to achieve friction and pressure energy dissipation.

[0036] Specifically, Figure 8As shown, a curved energy dissipation section 531 is designed in the middle of the curved connecting plate 53. When encountering an earthquake, the curved part will become the weak link of the structure, thereby achieving the effect of energy dissipation. At the same time, circular perforations 16 are designed on the steel plates on both sides of the connecting plate. When they are connected to the I-beam, they can further dissipate energy through friction and pressure mechanisms.

[0037] The above components are transported to the site for assembly. The specific construction steps are as follows:

[0038] Before installing the steel tube concrete segment column 1, the predetermined installation position is first subjected to foundation treatment to ensure that the bridge pier can be firmly and stably located at the predetermined position.

[0039] When constructing the cap 2, the method of pouring on site is adopted, and a PVC pipe is pre-placed on the central axis of the steel tube concrete segment column 1, and a metal corrugated pipe is pre-buried around the pipe. After the unbonded prestressed tendons 6 at the bottom of the cap 2 are fixed, the first segment of the steel tube concrete segment column is installed. The bottom energy-absorbing steel bars 7 are inserted into the interior of the cap 2, and the gaps are filled with grouting to ensure the compactness and long-term durability of the joints.

[0040] Following the same steps, install each segment of the steel tube concrete segment column 1 one by one. The steel tube concrete segment column 1 is internally connected with energy-absorbing steel bars 7 and a non-bonded section is left near the connection part, while ensuring that the non-bonded prestressed tendons 6 run from the bottom of the pier of the steel tube concrete segment column 1 to the top of the pier. When the overall installation of the steel tube concrete segment column 1 is completed, the energy-absorbing steel bars 7 are placed, and the cap beam 3 is erected, and then all gaps are filled with grouting. Subsequently, preliminary tensioning operations are carried out on the top of the pier of the steel tube concrete segment column 1 using prestressed anchors 8 to ensure the stability of the structure. After all steps are completed, steel rods 9 are welded at the outer edge connection of the steel tube concrete segment column 1.

[0041] To erect the middle extension section 51, the lateral connection plates 54 and the curved connection plates 53 need to be firmly connected. Subsequently, the entire structure is regulated by tensioning the steel strands 55, thereby giving the structure a self-resetting capability.

[0042] After all installations are completed, the unbonded prestressed tendons 6 are tensioned, and the magnitude of the prestress is determined according to the anti-overturning moment required under the design earthquake action to provide the bridge pier with self-resetting capability.

[0043] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A double-column bridge pier structure system with multi-level earthquake protection and self-reset function, characterized in that: The double-column bridge pier comprises two steel tube concrete segmented columns (1) arranged between a bridge pedestal (2) and a cap beam (3), a connecting beam being arranged between the two steel tube concrete segmented columns (1), the connecting beam comprising a concrete cast-in-place connecting beam (4) arranged on the steel tube concrete segmented columns (1) and a steel segment prefabricated connecting beam (5) connecting the concrete cast-in-place connecting beams (4) on both sides; the steel segment prefabricated connecting beam (5) comprises an embedded section (52) fixedly connected to the concrete cast-in-place connecting beam (4), the embedded sections (52) on both sides are rotatably connected and connected to form an integral structure capable of consuming energy and self-resetting through a connecting plate (53) and a steel strand (55) provided with an energy-dissipating structure, so as to adapt to the overall deformation of the pier body; the steel tube concrete segmented columns (1) are provided with unbonded prestressed tendons (6) and energy-dissipating steel bars (7) for self-resetting, so as to adapt to the deformation of the pier body when the inter-segment joints of the steel tube concrete segmented columns (1) swing.

2. A double-column bridge pier structure system with multi-level earthquake protection and self-reset function according to claim 1, characterized in that: The embedded sections (52) on both sides are connected via a middle extension section (51), and both ends of the middle extension section (51) are rotatably connected to the embedded sections (52) via vertically arranged lateral connection plates (54).

3. A double-column bridge pier structure system with multi-level earthquake protection and self-reset function according to claim 2, characterized in that: The embedded section (52) and the middle extension section (51) are fastened to the embedded section (52) via a transversely arranged connecting plate (53); the steel strand (55) passes through the middle extension section (51) and the embedded sections (52) on both sides, and is tensioned and fixed to ensure the stability of the overall structure of the steel section prefabricated connecting beam (5).

4. A double-column bridge pier structure system with multi-level earthquake protection and self-reset function according to claim 3, characterized in that: The connecting plate (53) is provided with a curved energy-absorbing section (531).

5. A double-column bridge pier structure system with multi-level earthquake protection and self-reset function according to any one of claims 1 to 4, characterized in that: The unbonded prestressed tendons (6) are built into the steel tube concrete segment column (1), and the two ends thereof pass through the pedestal (2) and the cap beam (3) respectively, and are tensioned and fixed by prestressed anchors (8).

6. A double-column bridge pier structure system with multi-level earthquake protection and self-reset function according to claim 5, characterized in that: Each segment of the steel tube concrete segment column (1) is provided with energy-absorbing steel bars (7), and the energy-absorbing steel bars (7) in adjacent segments are connected in sequence; the energy-absorbing steel bars (7) in the segments at both ends extend to the pedestal (2) and the cap beam (3) respectively.

7. A double-column bridge pier structure system with multi-level earthquake protection and self-reset function according to claim 6, characterized in that: Steel bars (9) are welded at the connection points of the outer edges of adjacent segments in the steel tube concrete segmented column (1).

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