Modularly assembled bridge piers that can be dynamically reset

Abstract

The application relates to a dynamically-resettable modular assembled bridge pier, which comprises a connecting beam, an assembled module, an anchor foundation, prestressed tendons, an external filling block and prestressed tendon anchorage; the assembled module comprises four mutually superposed bridge pier bodies, the upper end of the bridge pier body is provided with the connecting beam, the lower end of the bridge pier body is provided with the anchor foundation, a bidirectional gentle slope contact interface with an inner concave upper surface and an outer convex lower surface is arranged between adjacent assembled modules, and the external filling block is arranged; the prestressed tendons are arranged in the assembled module, and the prestressed tendon anchorage is arranged on the prestressed tendons. The application is a novel modular assembled bridge pier which can form a seismic isolation system with large horizontal flexibility at the epicenter, can eliminate residual sliding displacement by using the energy of the peak of an earthquake before the end of the earthquake and can keep the minimum limited use function, and can restore the structural stiffness and continue to be normally used after slight repair.

Description

Technical Field

[0001] This invention relates to the field of fully prefabricated bridge construction, and more specifically, to a modularly assembled bridge pier that can be dynamically reset. Background Technology

[0002] The construction of transportation infrastructure has a significant driving effect on national economic and social development. With the urbanization effect and people's aspirations for a better and more convenient life, urban road construction goals are gradually shifting towards "building more roads," "high-quality roads," and "faster roads." The market demand for rapid reconstruction projects of urban roads (elevated roads) continues to expand, and modular assembled bridge piers have become an important means to achieve rapid construction of fully prefabricated bridges. Fully prefabricated bridges are mostly used in non-seismic and low-intensity areas, and their piers are still mainly rigidly connected. Due to insufficient understanding of their dynamic performance, the structural seismic resistance concept adopts "ductility" design. Typical fully prefabricated urban elevated bridges mostly use double-column frame piers. Compared with single-column piers, frame piers have a lower equivalent height-to-width ratio and a lower vertical bearing stress level. The seismic damage to the bridge is mostly related to shear damage to the pier body, making them more suitable for seismic isolation and damping designs to improve overall resilience. As a vital lifeline project for cities, developing and designing modular assembled bridge piers can gradually shift towards a resilient seismic resistance design concept, which is of great significance for improving the post-disaster functional recoverability of bridges, ensuring the normal operation of cities after disasters, and promoting sustainable social development.

[0003] Existing modular assembled bridge piers mostly employ a prestressed rocking structure system combined with external energy-dissipating components to achieve a tough seismic design. However, their horizontal structural deformation depends solely on the rocking angle at the pier base. An increase in the displacement angle inevitably leads to a sharp increase in the vertical prestressed fastening load, accompanied by a sharp reduction in the compressive area of ​​the concrete at the pier base, resulting in significant crush damage. Rocking behavior has high recovery performance but poor energy dissipation properties; slippage behavior has high energy dissipation properties, but its recovery performance requires external force intervention. A novel modular assembled bridge pier design characterized by a hybrid slippage and rocking behavior has low damage characteristics and high cost-effectiveness in energy dissipation. However, the residual slippage displacement caused by inter-layer sliding between modules is difficult to eliminate, and the functional recoverability at the end of the vibration is poor. Under rare seismic sources, the concrete in the compressive zone at the pier base of the tough modular assembled bridge pier suffers severe crush damage due to the vertical prestressed fastening effect, and the residual sliding displacement is difficult to eliminate, requiring human intervention to restore the pier's function. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a modular assembled bridge pier that can be dynamically reset. It can trigger a large horizontal flexibility at the epicenter to form a seismic isolation system, and can also use the peak energy of the earthquake to eliminate residual slip displacement and maintain the minimum usability before the end of the earthquake. With a little repair, the structural stiffness can be restored and it can continue to be used normally.

[0005] The technical solution adopted by the present invention to solve its technical problem is: to construct a modular assembly pier that can be dynamically reset, including a connecting beam, an assembly module, an anchorage foundation, prestressed tendons, an external filling block, and prestressed tendon anchors.

[0006] The assembly module includes four stacked blocks to form the pier body. A connecting beam is provided at the upper end of the pier body, and an anchorage foundation is provided at the lower end of the pier body. An external filling block is provided between adjacent assembly modules. Prestressed tendons are provided inside the assembly module, and prestressed tendon anchors are provided on the prestressed tendons.

[0007] According to the above scheme, the connecting beam is provided with an anchoring space for prestressed tendons, and the assembly module set at the top of the pier body and the connecting beam are provided with shallow pits to prevent slippage when the pier top surface shakes irregularly.

[0008] The anchorage foundation is provided with an anchorage space for prestressed tendons. The assembly module located on the bottom surface of the pier body and the contact surface with the connecting beam are provided with shallow pits to prevent slippage and displacement when the top surface of the pier is irregularly shaken.

[0009] According to the above scheme, gaps are set at the four vertices of the assembly module, and the external filling block is set in the gaps.

[0010] According to the above scheme, the prestressed tendons and the assembly module are connected by grouting material in the overlapping sections.

[0011] According to the above scheme, the external filler block has a folded corner configuration, and the external filler block is bonded to the assembly module by adhesive.

[0012] According to the above scheme, the upper and lower surfaces of the assembly module have slopes, and the assembly module is a bidirectional gently sloping contact interface with a concave upper surface and a convex lower surface.

[0013] According to the above scheme, the slope angle of the assembly module is set between 3° and 8°, and the concave upper surface and convex lower surface of the assembly module can realize the assembly and positioning of the upper and lower modules.

[0014] According to the above scheme, the concave upper surface and the convex lower surface of the assembly module are subjected to bidirectional gentle slope interface lubrication treatment, and the dynamic friction coefficient of the lubrication interface of the assembly module after gentle slope interface lubrication treatment is between 0.05 and 0.1.

[0015] According to the above scheme, a pre-embedded prestressed corrugated pipe is set in the assembly module; the prestressed corrugated pipe provides grouting space for the prestressed tendons and the assembly module, forming a partially bonded prestressed system.

[0016] The modularly assembled bridge pier with dynamic repositionability according to the present invention has the following advantages:

[0017] 1. This invention achieves the dynamic reset principle by combining the gentle slope of the assembly module with the interface lubrication properties. It has the excellent characteristic of using the residual energy of the seismic source to assist the bridge pier in dynamic reset. The bridge structure has a high cost performance, low damage during the earthquake, and strong functional recoverability after the earthquake ends.

[0018] 2. In this invention, when the bridge pier is subjected to extreme horizontal overburden force from the seismic source, the prestressed tendon debonding mechanism is triggered first, followed by the module sliding mechanism, which together improves the horizontal flexibility of the bridge pier and alleviates the plastic damage to the material in the pier's bending and shear stress concentration area caused by the horizontal deformation caused by the seismic shaking and sliding. This transforms the bridge pier structure system into a seismic isolation structure system.

[0019] 3. In this invention, the bridge piers use prestressed tendons, which do not require high tension prestress. After the modules slide out due to vibration, they can gradually slide back to the center position under the action of residual energy of the seismic source. This can ensure the foundation's function after the vibration ends. After simple repair, the bridge pier's stiffness can be restored to meet normal use functions. Attached Figure Description

[0020] The present invention will be further described below with reference to the accompanying drawings and embodiments. In the accompanying drawings:

[0021] Figure 1 This is a structural schematic diagram of the modularly assembled bridge pier that can be dynamically reset according to the present invention;

[0022] Figure 2 This is a schematic diagram of the assembly module structure of the present invention;

[0023] Figure 3 This is a schematic diagram of the replaceable external filler block structure of the present invention. Detailed Implementation

[0024] To provide a clearer understanding of the technical features, objectives, and effects of the present invention, specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0025] like Figure 1-3 As shown, the modularly assembled bridge pier with dynamic repositioning according to the present invention includes a connecting beam 1, an assembly module 2, an anchorage foundation 3, prestressing tendons 4, an external filling block 5, and prestressing tendon anchors 6.

[0026] Assembly module 2 comprises four stacked blocks forming the pier body. A connecting beam 1 is installed at the upper end of the pier body, and an anchoring foundation 3 is installed at the lower end. External infill blocks 5, with an angled configuration, are installed between adjacent assembly modules 2 and are bonded to the assembly modules 2. Prestressing tendons 4 are installed within assembly modules 2, and prestressing tendon anchors 6 are installed on the prestressing tendons 4. Assembly modules 2 and prestressing tendons 4 are connected only at overlapping points. The prestressing tendons 4 and assembly modules 2 are connected by grouting material in the overlapping sections; the non-contact parts are exposed to air and filled by the external infill blocks 5, which are bonded to the assembly modules 2 and do not function as load-bearing components, but rather assist in forming a partially bonded prestressed system. The grouting bond between the prestressing tendons 4 and assembly modules 2 can lead to adhesive slippage under extreme seismic source horizontal forces, triggering the structural seismic flexibility. The prestressed tendon anchor 6 is a conventional anchor, but only the minimum prestress required to ensure the prestressed tendon 4 is straightened is applied. This serves as a safety reserve to prevent the assembly module 2 from loosening and falling off due to the failure of all bonding of the prestressed tendon 4.

[0027] An anchorage space for the prestressing tendons 4 is provided within the connecting beam 1. Shallow pits are provided at the contact surface between the assembly module 2, located at the top of the pier, and the connecting beam 1 to limit slippage caused by irregular shaking of the pier top surface. These pits partially restrict slippage caused by irregular shaking of the pier top surface, minimizing the residual slippage displacement at the contact point between the pier and the connecting beam 1. Similarly, an anchorage space for the prestressing tendons 4 is provided within the anchorage foundation 3. Shallow pits are provided at the contact surface between the assembly module 2, located at the bottom of the pier, and the connecting beam 1 to limit slippage caused by irregular shaking of the pier top surface. These pits partially restrict slippage caused by irregular shaking of the pier bottom surface, minimizing the residual slippage displacement at the contact point between the pier and the anchorage foundation 3.

[0028] Assembly module 2 has sloped upper and lower surfaces, forming a bidirectional gently sloping contact interface 201 with a concave upper surface and a convex lower surface. The slope angle of assembly module 2 is set between 3° and 8°. The concave upper surface and convex lower surface of assembly module 2 enable the assembly and positioning of the upper and lower modules. The interlocking of the concave and convex slopes of the upper and lower modules facilitates precise positioning during assembly. The gentle slope can provide a component of gravity to participate in the regulation of the pier's rocking and sliding behavior, providing a stable and constant restoring force, improving the pier's restoring performance, reducing residual sliding displacement of the pier, and improving the structural vibration-induced functional recovery performance. The concave upper surface and convex lower surface of assembly module 2 undergo bidirectional gently sloping interface lubrication treatment 202, resulting in a dynamic friction coefficient of the lubrication interface between 0.05 and 0.1. The bidirectional gentle slope interface lubrication treatment 202 involves lubricating the assembly module 2 with the bidirectional gentle slope contact interface 201. The lubricating medium used should be non-volatile and resistant to heavy pressure, and the dynamic friction coefficient of the lubricated interface should be between 0.05 and 0.1. After lubrication treatment, the bidirectional gentle slope contact interface 201 is more likely to trigger contact surface slippage behavior, and the friction energy dissipation properties are more stable. A suitable interface friction coefficient (0.05-0.1) combined with the gentle slope angle (3°-8°) can realize the use of residual energy from the seismic source to assist in the dynamic repositioning of the bridge pier structure, effectively improving the structural vibration end-function recovery performance. A pre-embedded prestressed corrugated pipe 203 is set in the assembly module 2; the prestressed corrugated pipe 203 provides grouting space for the prestressed tendons 4 and the assembly module 2, forming a partially bonded prestressed system. The grouting material within the prestressed corrugated pipe 203 can undergo bonding failure under extreme seismic source horizontal force, triggering the bonding slippage behavior between the prestressing tendon 4 and the assembly module 2. It possesses certain energy dissipation properties and can improve the structural horizontal flexibility under strong earthquakes, inducing the horizontal shear force of the seismic source to be transmitted upwards to the pier, thereby triggering inter-layer slippage behavior between modules, further improving the structure's horizontal deformation capacity under strong earthquakes, and achieving a structural toughness-based seismic isolation system. External infill blocks 5 can be installed to fill the gaps 204 between the unbonded sections of the prestressing tendon 4 and the assembly module 2, ensuring the uniformity and integrity of the pier's appearance during normal use. When encountering strong seismic source horizontal loads, if inter-layer slippage occurs between the assembly modules 2, the external infill blocks 5 will be sheared off, exposing the gaps 204, providing space for shear deformation between the assembly modules 2. At the end of the vibration, the gaps 204 can be repeatedly grouted to restore the structural horizontal stiffness, and a new external infill block 5 can be installed to ensure the normal functioning of the pier.

[0029] The working principle of this invention is as follows:

[0030] During normal use, the bidirectional gentle slope contact interface 201 of the assembly module 2 provides slope resistance, the bidirectional gentle slope interface lubrication treatment 202 provides maximum static friction, and the pre-embedded prestressed corrugated pipe 203 and prestressed tendon 4 provide bonding force. Under the combined action, the pier has the horizontal stiffness and lateral force resistance to meet the functional requirements.

[0031] Under the influence of rare earthquakes

[0032] First stage: The horizontal shear force from the seismic source is first transmitted to the anchorage foundation 3. The pier composed of the assembly module 2 induces a swaying tendency. The enhanced swaying behavior will trigger the bond failure behavior between the prestressed tendon 4 and the bottom assembly module 2, thus causing bond slippage. Under the premise of suppressing the tendency of the pier bottom swaying angle to expand, the energy dissipation properties of the structure are partially improved.

[0033] Second stage: The horizontal shear force from the seismic source is transmitted to the bidirectional gentle slope contact interface 201. The enhanced inter-story shear force will trigger the inter-story slippage behavior between the assembled modules 2, thereby improving the horizontal deformation capacity of the structure, continuously suppressing the trend of the pier bottom rocking angle expansion, and further improving the energy dissipation properties of the structure.

[0034] The third stage: The horizontal shear force at the earthquake source continues to be transmitted upward. Similar to the debonding and slippage behaviors in the first two stages, the structure's horizontal deformation capacity will continue to be improved, enhancing the overall energy dissipation properties of the structure.

[0035] Fourth stage: After the peak response of the earthquake source ends, the residual energy range of the earthquake source begins. In this section, the amplitude of the reciprocating displacement response caused by the earthquake source is weakened. The assembly module 2, which is equipped with a 3°-8° bidirectional gentle slope and a lubrication friction coefficient of 0.05-0.1, will use the residual energy of the earthquake source to dynamically reset the bridge pier by using the gravity component as the reset force in small-amplitude reciprocating swaying. After the earthquake ends, the residual slip displacement of the bridge pier should be eliminated. At this time, the bridge pier still has a high horizontal flexibility, but its bearing capacity can maintain the minimum passage function.

[0036] Fifth stage: Grouting can be repeated at the gap 204 of the external filling block 5 to re-bond the prestressed tendon 4 to the assembly module 2, restore the horizontal stiffness and lateral force resistance of the pier, replace the new external filling block 5, and ensure the normal use function of the pier.

[0037] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of the present invention without departing from the spirit and scope of the claims. All of these forms are within the protection scope of the present invention.

Claims

1. A modular assembly bridge pier that is dynamically resettable, characterized by, The connecting beam, the assembly module, the anchor foundation, the prestressed tendon, the external filling block and the prestressed tendon anchorage are provided. The assembly module comprises four blocks of piers stacked on each other to form a pier body, the upper end of the pier body is provided with a connecting beam, the lower end of the pier body is provided with an anchor foundation, the external filling block is arranged between adjacent assembly modules, the prestressed tendon is arranged in the assembly module, and the prestressed tendon anchorage is arranged on the prestressed tendon. The four vertices of the assembly module are provided with gaps, and the external filling block is arranged in the gaps. The prestressed tendon and the assembly module are connected by grouting of the grouting material in the overlapping section. The upper and lower surfaces of the assembly module have slopes, and the assembly module has a bidirectional gentle slope contact interface with a concave upper surface and a convex lower surface. The gentle slope angle of the assembly module is arranged to be between 3° and 8°, and the concave upper surface and the convex lower surface of the assembly module can realize the assembly positioning of the upper and lower modules. The concave upper surface and the convex lower surface of the assembly module are subjected to bidirectional gentle slope interface lubrication treatment, and the lubrication interface dynamic friction coefficient of the assembly module subjected to the gentle slope interface lubrication treatment is between 0.05 and 0.

1.

2. The dynamically resettable modular assembly pier of claim 1, wherein, The connecting beam is provided with an anchoring space for the prestressed tendon, and the assembly module arranged at the top of the pier body is provided with a shallow pit on the contact surface of the connecting beam to limit the dislocation and sliding of the irregular shaking of the pier top surface. The anchor foundation is provided with an anchoring space for the prestressed tendon, and the assembly module arranged at the bottom of the pier body is provided with a shallow pit on the contact surface of the connecting beam to limit the dislocation and sliding of the irregular shaking of the pier top surface.

3. The dynamically resettable modular assembly bridge pier of claim 1, wherein, The external filling block is of a corner configuration, and the external filling block is attached to the assembly module by adhesion.

4. The dynamically resettable modular assembly pier of claim 1, wherein, The assembly module is provided with a pre-buried prestressed corrugated pipe, the prestressed corrugated pipe provides a grouting space for the prestressed tendon and the assembly module, and forms a partial bonded prestressed system.

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