Prestressed lifting system for segmental assembled pier

Abstract

The application relates to a prestress lifting system for a segmental assembled pier, belonging to the field of bridge design. When the segmental assembled pier of the present stage is subjected to an earthquake load, transverse displacement or cracks are easily generated between the two adjacent segments of the segmental assembled pier along with the swing of the segmental assembled pier, thus leading to the decrease of the rigidity and the bearing capacity of the overall structure. The application comprises prestressed tendons, the prestressed tendons longitudinally penetrating through the multiple segments of the pier and being anchored, N prestress lifting units being axially connected in series on the prestressed tendons, each prestress lifting unit comprising at least one prestress lifting elastic piece, a reserved clamping groove being formed in each segment of the pier, the prestress lifting elastic piece being axially clamped in the reserved clamping groove, and the prestress lifting elastic piece being connected with the prestressed tendon to bear part of the tension stress suffered by the prestressed tendon. The application is mainly used for lifting the prestress of the prestressed tendon and realizing the functions of vibration reduction and energy consumption.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of bridge design, and particularly relates to a prestress lifting system for segmental assembly pier. BACKGROUND

[0002] China is one of the countries with relatively frequent and strong seismic activities in the world, especially in the western mountainous areas, which are mostly located in seismic belt regions. As an important part of the transportation network, once the bridge is damaged or collapsed in an earthquake, it will directly threaten the safety of passing vehicles and pedestrians, and even cause secondary disasters such as traffic jams, fires, etc., causing great loss of life and property. Therefore, improving the seismic performance of the pier is an inevitable requirement to protect the safety of people's life and property.

[0003] Although segmental assembly piers exhibit significant advantages in terms of rapid construction and cost-effectiveness of bridges, their seismic performance still has certain deficiencies compared to traditional monolithic cast piers. Under the action of earthquakes, due to the existence of the connecting interface between segments, the segmental assembly structure is more prone to lateral relative displacement or cracking, resulting in a decrease in the stiffness and carrying capacity of the overall structure. In addition, factors such as the quality of the connection between segments and the level of prestress will directly affect the stability of the seismic performance. Therefore, in earthquake-prone regions, special attention needs to be paid to the seismic design of segmental assembly piers, and effective measures need to be taken to enhance the connection strength between segments and optimize the prestress arrangement, in order to improve the overall seismic performance and ensure the safety and stability of the bridge structure in earthquakes. SUMMARY

[0004] Therefore, the present application provides a prestress lifting system for segmental assembly piers, which uses a prestress lifting unit to bear part of the tensile stress of the prestressed tendon, reduces the swing amplitude of the segmental assembly pier under seismic load, and effectively resists the lateral deformation of the segmental assembly pier and maintains the shape of the pier body.

[0005] The technical solution adopted by the present application to solve the above technical problems is as follows:

[0006] A prestress lifting system for segmental assembly piers, comprising a prestressed tendon, the prestressed tendon longitudinally penetrating and anchoring in multiple segments of the pier, and N prestress lifting units being axially connected in series on the prestressed tendon, each prestress lifting unit corresponding to a segment of the pier; each prestress lifting unit comprising at least one prestress lifting elastic member, a reserved clamping groove being formed in each segment of the pier, the prestress lifting elastic member being clamped in the corresponding reserved clamping groove, each prestress lifting elastic member being connected with the prestressed tendon, and under the action of seismic load, the prestress lifting elastic member bearing part of the tensile stress of the prestressed tendon.

[0007] Preferably, the prestressed lifting elastic member is a compression coil spring, and the elastic force of the prestressed lifting elastic member increases with the increase of the height of the segmental assembled bridge pier.

[0008] Preferably, each prestressed lifting unit further comprises at least one deformable elastic hinge, each prestressed lifting elastic member is connected with the prestressed tendon via the elastic hinge, and the elastic hinge pushes the prestressed lifting elastic member into the reserved clamping groove and clamps the prestressed lifting elastic member when the prestressed lifting elastic member is assembled with the bridge pier.

[0009] Preferably, each elastic hinge comprises a parallelogram frame and at least one double-hook spring connected to the parallelogram frame, the double-hook spring stretches or retracts with the deformation of the parallelogram frame, and the prestressed lifting elastic member and the prestressed tendon are respectively connected to two opposite corners of the parallelogram frame, and the parallelogram frame pushes the prestressed lifting elastic member into the reserved clamping groove when the parallelogram frame recovers from the compressed state to the open state under the resilience of the double-hook spring.

[0010] Preferably, a plurality of vortex springs are embedded between two adjacent bridge piers in the circumferential direction, and the vortex springs are arranged close to the edge of the bridge pier; one end of the vortex spring is embedded into the upper bridge pier, and the other end is embedded into the lower bridge pier, and the elastic force of the vortex spring increases with the increase of the height of the segmental assembled bridge pier.

[0011] Preferably, the top end anchoring mechanism for anchoring the prestressed tendon is further provided, the top end anchoring mechanism is installed at the top of the segmental assembled bridge pier, and the upper end of the prestressed tendon is connected to the top end anchoring mechanism and is in tension; the top end anchoring mechanism comprises a damping leaf spring, the concave surface of the damping leaf spring faces the segmental assembled bridge pier, one end of the damping leaf spring is hinged to the segmental assembled bridge pier, and the other end of the damping leaf spring abuts against the surface of the segmental assembled bridge pier, the other end of the damping leaf spring slides to the side with the increase of the impact load, and the damping leaf spring yields to deform to resist the load impact.

[0012] Preferably, the top end anchoring mechanism further comprises a cylindrical rubber pad installed between the damping leaf spring and the segmental assembled bridge pier, and a deformation space is left between the lower surface of the damping leaf spring and the cylindrical rubber pad to reduce the probability of buckling deformation of the damping leaf spring.

[0013] Preferably, the damping leaf spring is stacked by a plurality of leaf springs, the size of the plurality of leaf springs increases from top to bottom, and a rubber pad layer is arranged between two adjacent leaf springs.

[0014] Preferably, a bottom end anchoring mechanism for anchoring the prestressed tendon is further included, the bottom end anchoring mechanism is cast in the foundation of the segmental assembled pier, the bottom end of the prestressed tendon is connected to the bottom end anchoring mechanism and is tensioned, the bottom end anchoring mechanism comprises a bottom reaction steel pad, a bottom anchor head and a bottom anchor head clamping piece, the prestressed tendon passes through the bottom reaction steel pad, the bottom anchor head and the bottom anchor head clamping piece in sequence and is fixedly connected with the bottom anchor head clamping piece.

[0015] Compared with the prior art, the present application has the following beneficial effects:

[0016] 1. The prestressed tendon is connected with each pier segment via the prestressed lifting unit, which is equivalent to dividing the prestressed tendon into multiple segments. When the seismic transverse wave occurs, the two adjacent pier segments tend to open, which causes the prestressed tendon between the two adjacent pier segments to be tensioned and elongated. The prestressed tendon transmits part of the tension stress to the bidirectional high-strength spring in the prestressed lifting unit, and the bidirectional high-strength spring is compressed and absorbs this part of the stress. The prestressed lifting unit increases the connection force between the two adjacent pier segments and reduces the loss of prestress caused by stress relaxation of the prestressed tendon. Therefore, the design of the prestressed lifting unit can effectively resist the lateral deformation of the assembled pier, reduce the amplitude of the swing of the segmental assembled pier, and effectively maintain the shape of the assembled pier.

[0017] 2. When the seismic transverse wave occurs, one side of the two adjacent pier segments is opened, and the two ends of the vortex spring are pulled by the two pier segments respectively, so that the elastic potential energy is stored. Therefore, the vortex spring can be used to absorb the lateral load of the earthquake and reduce the amplitude of the swing of the segmental assembled pier. In addition, the vortex spring is flat, which will not affect its performance after the two pier segments are assembled. If a common spring is used, the spring cannot absorb energy when it is poured into the pier.

[0018] 3. When the seismic longitudinal wave occurs, the segmental assembled pier bears the longitudinal load, and the shock-absorbing leaf spring deforms when it is stressed. The end of the shock-absorbing leaf spring in contact with the segmental assembled pier slides to the side and gradually straightens, and the yield deformation of the shock-absorbing leaf spring is used to resist the instantaneous impact of the load. The two ends of the shock-absorbing leaf spring are not fixedly connected, but one end of the shock-absorbing leaf spring is hingedly connected and the other end is slidably connected, so that the shock-absorbing leaf spring can deform more easily and absorb more impact load, thereby reducing the impact load borne by the segmental assembled pier. At the same time, it can also prevent the impact load from being transmitted to the segmental assembled pier through the connection end of the shock-absorbing leaf spring and the segmental assembled pier, or the shock-absorbing leaf spring from being unable to continue to resist the next wave of load due to the buckling deformation caused by the large impact force.

[0019] 4. When the damping leaf spring is deformed to a certain extent, the lower surface of the damping leaf spring abuts on the cylindrical rubber pad, which not only can serve as the buffer for the downward deformation of the damping leaf spring, but also can avoid the breakage of the damping leaf spring caused by the excessive load. After the end of the instantaneous load, the damping leaf spring is reset by the resilience of the damping leaf spring, and can continue to play a role in the next earthquake. BRIEF DESCRIPTION OF DRAWINGS

[0020] The accompanying drawings are included to provide a further understanding of the present application and are incorporated in and constitute a part of this specification.

[0021] Figure 1 The overall structure schematic diagram of the prestress lifting system for segmental assembled bridge pier according to the present application.

[0022] Figure 2 The state schematic diagram of the segmental assembled bridge pier when swinging in the lateral wave of earthquake.

[0023] Figure 3 The structure schematic diagram of the prestress lifting unit.

[0024] Figure 4 The structure schematic diagram of the prestress lifting unit assembled into the bridge pier.

[0025] Figure 5 The three-dimensional view of the prestress lifting unit.

[0026] Figure 6 The structure schematic diagram of the prestress lifting unit in the reserved hole during the process of being assembled into the bridge pier.

[0027] Figure 7 The structure schematic diagram of the top anchoring mechanism.

[0028] Figure 8 The structure schematic diagram of the bottom anchoring mechanism.

[0029] Figure 9 The structure schematic diagram of the vortex spring.

[0030] Figure 10 The response process of the prestress lifting system according to the present application.

[0031] BRIEF DESCRIPTION OF DRAWINGS: 1 - prestressed tendon; 2 - prestress lifting unit; 21 - prestress lifting elastic member; 22 - elastic hinge; 221 - parallel four-bar linkage frame; 222 - double-hook spring; 3 - top anchoring mechanism; 31 - top anchoring head clamping piece; 32 - arc bottom outer anchorage device; 33 - damping leaf spring; 331 - leaf spring; 332 - rubber pad layer; 34 - counterforce steel pad; 35 - cylindrical rubber pad; 4 - bottom anchoring mechanism; 41 - bottom counterforce steel pad; 42 - bottom anchoring head; 43 - bottom anchoring head clamping piece; 5 - bridge pier; 51 - reserved clamping groove; 52 - reserved hole; 6 - vortex spring. DETAILED DESCRIPTION

[0032] In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the following will clearly and completely describe the technical solutions in the embodiments with reference to the drawings in the embodiments of the present application. The following embodiments are used to explain the present application but not to limit the scope of the present application.

[0033] When the seismic transverse wave occurs, the foundation of the lower end of the segmental assembled bridge pier is subjected to reciprocating transverse load, and the segmental assembled bridge pier will swing to a certain amplitude under inertia, especially the higher the position, the greater the swing amplitude. This leads to the adjacent two bridge piers between the segmental assembled bridge pier to produce the trend of opening away from the swing side and the trend of extrusion on the swing side, that is, the adjacent two bridge piers between the segmental assembled bridge pier form alternating axial tension and axial extrusion force on both sides. The segmental assembled bridge pier is more prone to transverse relative displacement or cracking under axial tension, resulting in the decline of the stiffness and carrying capacity of the overall structure. When the transverse load force generated by the earthquake is small, the axial tension generated between the adjacent two bridge piers is relatively small, and the prestress of the prestressed tendon 1 itself can completely resist the axial tension to ensure the shape of the segmental assembled bridge pier. When the transverse load force generated by the earthquake is large, the axial tension generated between the adjacent two bridge piers is relatively large, and the prestress of the prestressed tendon 1 itself cannot completely resist it. This axial tension can cause the prestressed tendon 1 to relax and lose prestress, and finally cannot resist the transverse deformation of the assembled bridge pier and maintain the shape of the pier body. Therefore, the present embodiment provides a prestress lifting system for segmental assembled bridge pier.

[0034] As Figures 1 to 6As shown, a plurality of reserved holes 52 are evenly opened in each segmental pier 5 along the circumference and close to the edge of the pier. After the assembly of the multi-segmental pier 5, the corresponding reserved holes 52 are spliced into a channel penetrating the upper and lower surfaces of the entire pier, and a prestressed tendon 1, preferably a steel strand, penetrates each channel. The prestressed tendon 1 is anchored to the upper and lower surfaces of the entire pier and is in tension. The prestressed tendon 1 has N prestressed lifting units 2 connected in series in the axial direction, the number of the prestressed lifting units 2 is the same as the number of the segments of the entire pier, and the prestressed tendon 1 is connected with each segmental pier through the prestressed lifting units 2. Specifically, each prestressed lifting unit 2 includes at least one prestressed lifting elastic member 21, preferably four, and the four prestressed lifting elastic members 21 are evenly arranged along the circumference. A reserved clamping groove 51 is opened in each segmental pier, the number of the reserved clamping grooves 51 is the same as that of the prestressed lifting elastic members 21, and the reserved clamping grooves 51 are communicated with the reserved holes 52; the prestressed lifting elastic members 21 are axially clamped in the reserved clamping grooves 51, and each prestressed lifting elastic member 21 is connected with the prestressed tendon 1. Under the action of the seismic load, the prestressed lifting elastic members 21 bear part of the tensile stress of the prestressed tendon 1. In this embodiment, the prestressed tendon 1 is connected with each segmental pier through the prestressed lifting units 2, which is equivalent to dividing the prestressed tendon 1 into multiple segments. When the seismic transverse wave occurs, the two adjacent segmental piers tend to be separated, which causes the prestressed tendon 1 between the two adjacent segmental piers to be in tension and elongated. The prestressed tendon 1 transmits part of the tensile stress to the prestressed lifting elastic members 21 in the prestressed lifting units 2, and the prestressed lifting elastic members 21 are compressed and absorb this part of the stress. Therefore, the prestressed lifting units 2 increase the connecting force between the two adjacent segmental piers and reduce the loss of prestress caused by the stress relaxation of the prestressed tendon 1. Therefore, the design of the prestressed lifting units 2 can effectively resist the transverse deformation of the segmental pier, reduce the swing amplitude of the assembled pier, and effectively maintain the shape of the segmental pier.

[0035] As the height of the segmental assembly pier increases, the axial tension between the two adjacent segmental piers increases, and the tensile stress of the prestressed tendon 1 increases. Therefore, as shown in the figure, Figure 2 In this embodiment, the prestressed lifting elastic member 21 is a high-strength compression spiral tendon, and as the height of the segmental assembly pier increases, the elastic force of the prestressed lifting elastic member 21 increases to bear more tensile stress.

[0036] Since the prestressed lifting unit 2 and the prestressed tendon 1 are fixed in advance, and each segmental pier is prefabricated, in order to ensure the strength of each segmental pier 5, the size of the reserved hole 52 is very small, only for the prestressed tendon 1 and the prestressed lifting unit 2 to pass through. Therefore, when the multi-segmental pier is assembled, the prestressed lifting elastic member 21 connected in series on the prestressed tendon 1 cannot be artificially assembled into the reserved clamping groove 51 of the pier. Therefore, as shown in the figure, Figure 2 ,Figure 3 and Figure 4 As shown, in this embodiment, each prestressed lifting unit 2 also includes at least one deformable elastic hinge 22, and the number of elastic hinges 22 is the same as the number of prestressed lifting elastic elements 21. Each prestressed lifting elastic element 21 is connected to the prestressed tendon 1 via an elastic hinge 22. Under the compression and rebound force of the elastic hinge 22, the prestressed lifting elastic element 21 is pushed from the reserved hole 52 of each pier section into the reserved slot 51, thereby fixing the prestressed lifting unit 2 to the pier. Specifically, each elastic hinge 22 includes a parallel four-bar frame 221 and at least one double-hook spring 222, preferably two double-hook springs 222, arranged side-by-side within the parallel four-bar frame 221. One double-hook spring 222 connects to two adjacent links in the parallel four-bar frame 221, and the other double-hook spring 222 connects to two other adjacent links in the parallel four-bar frame 221. The two double-hook springs 222 stretch or retract as the parallel four-bar frame 221 deforms. Figure 3 and Figure 4 When each pier segment is fitted onto the prestressing tendon 1, the parallel four-bar linkage 221 is compressed and the double hook spring 222 is stretched. The elastic hinge 22 narrows laterally and can pass through the reserved channel 52 of each pier segment. When the prestressing lifting unit 2 moves to the reserved slot 51 of the pier, the parallel four-bar linkage 221 opens under the rebound force of the double hook spring 222, pushing the prestressing lifting elastic member 21 into the reserved slot 51. The prestressing lifting elastic member 21 is locked inside the pier, completing the fixation of the prestressing tendon 1 to the corresponding pier. In this embodiment, the elastic hinge 22 not only has the ability to compress and deform, but also has a certain rigidity to recover deformation. With sufficient rigidity, it can push the prestressing lifting elastic member 21 into the reserved slot 51.

[0037] like Figure 2 As shown, although the prestressed lifting unit 2 can resist some of the tensile stress on the prestressed tendon 1, the tensile stress at the connection interface between two adjacent piers is actually the greatest, and it is also more likely to cause lateral displacement between the piers. Therefore, as Figure 1 and Figure 8As shown, a plurality of vortex springs 6 are embedded between two adjacent bridge piers in the circumferential direction, and the vortex springs 6 are arranged close to the edges of the bridge piers, one end of the vortex spring 6 is embedded into the upper bridge pier, and the other end is embedded into the lower bridge pier; as the height of the segmental assembled bridge pier increases, the elastic force of the vortex spring 6 increases. When the seismic transverse wave occurs, one side of the two adjacent bridge piers is opened, and the two bridge piers pull the two ends of the vortex spring 6, so that the elastic potential energy is stored, and therefore the transverse load of the earthquake can be absorbed by the vortex spring 6 to reduce the amplitude of the swing of the segmental assembled bridge pier; in addition, the reason for using the vortex spring 6 is that it is flat and will not affect the use performance after the two bridge piers are assembled. If a common spring is used, the spring cannot absorb energy when it is poured into the bridge pier.

[0038] As shown in FIG. 1, the segmental assembled bridge pier is composed of a plurality of bridge piers 2, and the bridge piers 2 are connected by a plurality of pre-stressed tendons 1. As shown, a plurality of vortex springs 6 are embedded between two adjacent bridge piers in the circumferential direction, and the vortex springs 6 are arranged close to the edges of the bridge piers, one end of the vortex spring 6 is embedded into the upper bridge pier, and the other end is embedded into the lower bridge pier; as the height of the segmental assembled bridge pier increases, the elastic force of the vortex spring 6 increases. When the seismic transverse wave occurs, one side of the two adjacent bridge piers is opened, and the two bridge piers pull the two ends of the vortex spring 6, so that the elastic potential energy is stored, and therefore the transverse load of the earthquake can be absorbed by the vortex spring 6 to reduce the amplitude of the swing of the segmental assembled bridge pier; in addition, the reason for using the vortex spring 6 is that it is flat and will not affect the use performance after the two bridge piers are assembled. If a common spring is used, the spring cannot absorb energy when it is poured into the bridge pier. Figure 7 As shown, since the earthquake not only produces seismic transverse waves but also produces seismic longitudinal waves, the segmental assembled bridge pier may still be damaged when subjected to the seismic longitudinal wave. Therefore, the embodiment also includes a top anchoring mechanism 3 for anchoring the pre-stressed tendon 1, the top anchoring mechanism 3 is installed at the top of the segmental assembled bridge pier, and the upper end of the pre-stressed tendon 1 is connected to the top anchoring mechanism 3 and is in tension; specifically, the top anchoring mechanism 3 includes a top anchoring head clamping piece 31, an arc bottom outer anchor 32, a damping plate spring 33 and a counterforce steel pad 34 arranged in sequence from top to bottom; the counterforce steel pad 34 is fixedly installed at the top of the segmental assembled bridge pier; the concave surface of the damping plate spring 33 faces the segmental assembled bridge pier, one end of the damping plate spring 33 is hinged to the counterforce steel pad 34, and the other end abuts against the surface of the counterforce steel pad 34, the other end of the damping plate spring 33 slides to the side with the increase of the impact load, and the damping plate spring 33 occurs yield deformation to resist the load impact. The arc bottom outer anchor 32 is arranged on the upper surface of the damping plate spring 33 and is attached, and a rubber pad layer is installed therebetween; the top anchoring head clamping piece 31 is conical and is inserted into the conical groove at the top of the arc bottom outer anchor 32. The pre-stressed tendon 1 penetrates the counterforce steel pad 34, the damping plate spring 33, the arc bottom outer anchor 32 and the top anchoring head clamping piece 31 in sequence from bottom to top, and is connected with the top anchoring head clamping piece 31. When the seismic longitudinal wave occurs, the segmental assembled bridge pier bears the longitudinal load, and the damping plate spring 33 deforms when subjected to force, the end of the damping plate spring 33 in contact with the segmental assembled bridge pier slides to the side and gradually straightens, and the yield deformation of the damping plate spring 33 resists the instantaneous impact of the load. In the embodiment, the two ends of the damping plate spring 33 are not installed in a fixed connection manner, but one end of the damping plate spring 33 is hinged, and the other end is connected in a sliding manner, so that the damping plate spring 33 is more likely to deform and absorb energy, and more impact load is converted into the yield deformation of the damping plate spring 33, reducing the impact load borne by the segmental assembled bridge pier. At the same time, it can also prevent the impact load from being transmitted to the segmental assembled bridge pier through the connection end of the damping plate spring 33 and the segmental assembled bridge pier, or the damping plate spring 33 is deformed due to the large impact force, and cannot continue to resist the next wave of load.

[0039] In the embodiment, the shock-absorbing leaf spring 33 is stacked by multiple leaf springs 331, the sizes of the multiple leaf springs 331 are sequentially increased from top to bottom, and the multiple leaf springs 331 are connected by U-shaped bolts to form a triangular structure. In this way, the triangular force principle is used, each layer of leaf spring can bear load uniformly, and the load bearing capacity and stability of the shock-absorbing leaf spring 33 are improved. In addition, a rubber pad 332 is arranged between two adjacent leaf springs 331, which can effectively reduce the direct friction between the leaf springs 331, thereby reducing the wear caused by friction and improving the load bearing capacity and durability.

[0040] In addition, the load of the longitudinal wave of the earthquake needs to be absorbed by the deformation of the shock-absorbing leaf spring 33, but when the longitudinal load is large, the shock-absorbing leaf spring 33 may be buckled and deformed into an irreversible state, thereby losing normal mechanical properties, and more seriously, the shock-absorbing leaf spring 33 may be broken. Therefore, as shown in the figure, Figure 6 The top anchoring mechanism 3 of the embodiment further includes a cylindrical rubber pad 35 installed between the shock-absorbing leaf spring 33 and the counterforce steel pad 34, and a deformation space is left between the lower surface of the shock-absorbing leaf spring 33 and the cylindrical rubber pad 35 to reduce the probability of buckling deformation of the shock-absorbing leaf spring 33. In the embodiment, a cylindrical rubber pad 35 is arranged below the shock-absorbing leaf spring 33, and a certain deformation space is left between the two. The deformation space not only provides space for the deformation of the shock-absorbing leaf spring 33, but also facilitates the shock-absorbing leaf spring 33 to absorb the load of the longitudinal wave of the earthquake by deformation. When the shock-absorbing leaf spring 33 is deformed to a certain extent, the lower surface of the shock-absorbing leaf spring 33 abuts against the cylindrical rubber pad 35, which not only serves as a buffer for the downward deformation of the shock-absorbing leaf spring 33, but also avoids the breakage of the shock-absorbing leaf spring 33 caused by excessive load. After the instantaneous load is over, the shock-absorbing leaf spring 33 is reset by its own resilience, and can continue to play a role in the next earthquake.

[0041] As shown in the figure, Figure 8 The embodiment further includes a bottom anchoring mechanism 4 for anchoring the prestressed tendon 1, the bottom anchoring mechanism 4 is cast in the foundation of the segmental assembled pier, and the bottom end of the prestressed tendon 1 is connected to the bottom anchoring mechanism 4 and is tensioned. Specifically, the bottom anchoring mechanism 4 includes a bottom counterforce steel pad 41, a bottom anchor head 42 and a bottom anchor head clamping piece 43 arranged from top to bottom, the prestressed tendon 1 passes through the bottom counterforce steel pad 41, the bottom anchor head 42 and the bottom anchor head clamping piece 43 in sequence, and is fixedly connected with the bottom anchor head clamping piece 43. This part is cast in the concrete as a fixed anchoring section to provide counterforce for prestressed tensioning.

[0042] The assembly process of the application is described in detail as follows:

[0043] Step one: pass the prestressed tendon 1 through the bottom counterforce steel base plate 41, and fix it with the bottom anchor head 42 and the bottom anchor head clamping piece 43; place the bottom end anchoring mechanism 4 with the prestressed tendon 1 in the foundation of the bridge pier, pour concrete and carry out normal temperature curing to the foundation to realize the fixation of the bottom end of the prestressed tendon 1 and provide counterforce for prestressed tensioning;

[0044] Step two: according to the elevation of each section of the bridge pier 5 and the position of the reserved slot of each section of the bridge pier, the corresponding prestressed lifting unit 2 is connected in series on the prestressed tendon 1 and fixed in advance along with the installation of the segmental bridge pier; after the completion of the installation of each section of the bridge pier, the fixation of the next prestressed lifting unit 2 is carried out;

[0045] Step three: when the segmental bridge pier 5 is hoisted, the elastic hinge 22 in the prestressed lifting unit 2 is tightened, the top end of the prestressed tendon 1 is pulled and passes through the reserved hole 52 in each section of the bridge pier 5, and after the prestressed lifting unit 2 reaches the reserved slot 51 of the design elevation, the elastic hinge 22 generates a thrust on the surrounding prestressed lifting elastic piece 21 under the restoring force of itself, and the prestressed lifting elastic piece 21 is embedded in the reserved slot 51;

[0046] Step four: after the completion of the installation of all the bridge piers, the prestressed tendon 1 passes through the top counterforce steel base plate 34, the cylindrical rubber pad 35, the damping plate spring 33 and the arc bottom outer anchor 32, is clamped by the top end anchor clamping piece 31 after being tensioned by the prestressed tensioning equipment, and the anchoring of the prestressed tendon is realized.

[0047] The maximum instantaneous load that can be resisted by the prestressed lifting system of the application can be calculated by the following formula:

[0048] F max =P w +P l +P s +P r (1)

[0049] In the formula: P w --- the initial prestress of the steel strand, according to the specification GB50010-2010 "Concrete Structure Design Specification", for prestressed concrete structure, the prestress is equal to 75% of the ultimate tensile strength of the steel strand;

[0050] P l --- the damping plate spring bearing capacity of the top end anchoring mechanism;

[0051] P s --- the spring bearing capacity of the prestressed lifting unit;

[0052] P r --- the bearing capacity of the vortex spring.

[0053] Based on formula (1), it can be obtained that:

[0054]

[0055] wherein: δ-----the maximum deflection that the shock-absorbing leaf spring can produce;

[0056] b-----the width of the shock-absorbing leaf spring;

[0057] t-----the thickness of the shock-absorbing leaf spring;

[0058] a, n1-----constants, in actual engineering, the values of a and n1 need to be determined according to specific materials and load conditions;

[0059] n2-----the number of pier segments;

[0060] k1-----the elastic modulus of the high-strength compression spiral rib;

[0061] k2-----the elastic modulus of the vortex spring;

[0062] l-----the maximum deformation of the high-strength compression spiral rib.

[0063] The provision of the above calculation formula makes the prestressed lifting system for segmental assembled pier of the present application be able to set different design parameters according to different seismic intensities in different regions, so as to effectively resist seismic load, and after being loaded, to bend into elastic-plastic hysteresis deformation to absorb and dissipate seismic energy, and the working performance curve thereof changes with time during the response process as shown in Figure 10 When an earthquake occurs, the prestressed lifting system in normal working state enters the resistance stage under the influence of seismic longitudinal waves, the prestressed steel strand axial force instantaneously increases in this stage, the shock-absorbing leaf spring, rubber pad layer and high-strength compression spiral rib produce yield deformation to absorb seismic energy; then, under the influence of seismic transverse waves, the entire system enters elastic-plastic hysteresis deformation and stable pier body shape under the action of reciprocating load; after the earthquake, the system restores to normal working state by relying on its own potential energy, which is the recovery stage, and finally restores to the normal working state in the post-earthquake stage. After that, the prestressed lifting system for segmental assembled pier can again realize the above-mentioned action process under the action of an earthquake, thereby achieving the purpose of seismic resistance.

[0064] While the application has been described with reference to particular embodiments thereof, it is to be understood that these embodiments are merely illustrative of the principles and applications of the present application. It will be apparent to those skilled in the art that numerous modifications can be made within the scope of the present application as defined by the appended claims. It is intended that all such modification fall within the spirit and scope of the present application. It will be understood that the features described in connection with one embodiment can be used in connection with another embodiment.

Claims

1. A prestressed lifting system for segmental pier assembly, comprising prestressed tendons (1), wherein the prestressed tendons (1) longitudinally penetrate multiple pier segments (5) and are anchored thereto, characterized in that: N prestressing lifting units (2) are connected in series on the prestressing tendon (1) in the axial direction. Each prestressing lifting unit (2) corresponds to a section of bridge pier (5). Each prestressing lifting unit (2) includes at least one prestressing lifting elastic element (21). Each section of bridge pier has a reserved slot (51). The prestressing lifting elastic element (21) is installed in the corresponding reserved slot (51). Each prestressing lifting elastic element (21) is connected to the prestressing tendon (1). Under seismic load, the prestressing lifting elastic element (21) bears part of the tensile stress on the prestressing tendon (1).

2. The prestressed lifting system for segmental bridge piers according to claim 1, characterized in that: The prestressed lifting elastic member (21) is a compressed spiral bar, and the elastic force of the prestressed lifting elastic member (21) increases with the increase of the height of the segmented pier.

3. The prestressed lifting system for segmental bridge piers according to claim 1, characterized in that: Each prestressed lifting unit (2) also includes at least one deformable elastic hinge (22). Each prestressed lifting elastic element (21) is connected to the prestressed tendon (1) via the elastic hinge (22). When the prestressed lifting elastic element (21) is assembled with the pier, the elastic hinge (22) pushes the prestressed lifting elastic element (21) into the reserved slot (51) and locks it in place.

4. The prestressed lifting system for segmental bridge piers according to claim 3, characterized in that: Each elastic hinge (22) includes a parallel four-bar frame (221) and at least one double hook spring (222). The double hook spring (222) is connected to the parallel four-bar frame (221) and the double hook spring (222) stretches or retracts with the deformation of the parallel four-bar frame (221). The prestressed lifting elastic element (21) and the prestressing tendon (1) are respectively connected to two opposite corners of the parallel four-bar frame (221). When the parallel four-bar frame (221) recovers from the compressed state to the open state under the rebound force of the double hook spring (222), the parallel four-bar frame (221) pushes the prestressed lifting elastic element (21) into the reserved slot (51).

5. The prestressed lifting system for segmental bridge piers according to claim 1, characterized in that: Multiple spiral springs (6) are pre-embedded circumferentially between two adjacent piers, and the spiral springs (6) are set close to the edge of the pier; one end of the spiral spring (6) is pre-embedded in the upper pier and the other end is pre-embedded in the lower pier. As the height of the segmented pier increases, the elastic force of the spiral spring (6) increases.

6. The prestressed lifting system for segmental bridge piers according to claim 1, characterized in that: It also includes a top anchoring mechanism (3) for anchoring the prestressed tendons (1). The top anchoring mechanism (3) is installed on the top of the segmental pier. The upper end of the prestressed tendons (1) is connected to the top anchoring mechanism (3) and tensioned. The top anchoring mechanism (3) includes a damping leaf spring (33). The concave surface of the damping leaf spring (33) faces the segmental pier. One end of the damping leaf spring (33) is hinged to the segmental pier, and the other end abuts against the surface of the segmental pier. The other end of the damping leaf spring (33) slides laterally as the impact load increases. The damping leaf spring (33) undergoes yielding deformation to resist the impact of the load.

7. A prestressed lifting system for segmental bridge piers according to claim 6, characterized in that: The top anchoring mechanism 3 also includes a cylindrical rubber pad (35), which is installed between the damping leaf spring (33) and the segmental assembled pier, and leaves deformation space with the lower surface of the damping leaf spring (33) to reduce the probability of buckling deformation of the damping leaf spring (33).

8. A prestressed lifting system for segmental bridge piers according to claim 6, characterized in that: The damping leaf spring (33) is made up of multiple leaf springs (331) stacked together, and the size of the leaf springs (331) increases from top to bottom. A rubber pad (332) is provided between two adjacent leaf springs.

9. A prestressed lifting system for segmental bridge piers according to claim 1, characterized in that: It also includes a bottom anchoring mechanism (4) for anchoring the prestressed tendons (1). The bottom anchoring mechanism (4) is cast in the foundation of the segmental assembled pier. The bottom end of the prestressed tendons (1) is connected to the bottom anchoring mechanism (4) and tensioned. The bottom anchoring mechanism (4) includes a bottom reaction steel pad (41), a bottom anchor head (42) and a bottom anchor head clip (43). The prestressed tendons (1) pass through the bottom reaction steel pad (41), the bottom anchor head (42) and the bottom anchor head clip (43) in sequence and are fixedly connected to the bottom anchor head clip (43).

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