Construction method for bridge pier with full-prestressed duct grouting and external dampers

Abstract

The invention discloses a construction method for a full-prestressed duct grouting external damper pier. The method comprises the steps that firstly, single-beam sealing prestressed tendon assemblies are prepared, reinforcement frameworks are synchronously arranged, a mold is built, hollow sealing channel pipes are fixed, and prefabricated pier sections with shear keys, key grooves and channel connector reserved structures are formed through pouring maintenance; then butt joint is carried out through shear keys, auxiliary fixing is carried out through positioning pins, segment hoisting is completed, a prestressed tendon assembly is arranged in a penetrating mode, then tensioning is carried out to preset stress, locking is carried out through a sealing anchor plate, and then grouting is carried out on the hollow sealing channel; meanwhile, fixing parts are pre-embedded in the pier prefabricating stage, after the connecting bases are fixed through bolts, the in-vitro energy dissipation dampers are inserted and clamped through buckles to complete assembling, and finally a data acquisition device is connected to a detection opening of each connecting base to acquire stress of the corresponding prestressed tendon assembly and fitting position data of the dampers and the connecting bases. The bridge pier is stable in prestress, efficient in seismic resistance and energy consumption and convenient to construct and maintain, and meanwhile structural sealing performance and operation safety are guaranteed.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of pier construction, in particular to a full-prestressed duct grouting external damper pier construction method. BACKGROUND

[0002] In the construction of prefabricated piers, the technology of combining full-prestressed duct grouting with external dampers is an important means to improve the stability and seismic performance of the pier structure. It applies pre-tightening force through prestressed tendons to ensure the bearing capacity of the structure, relies on duct grouting to achieve sealing protection, and dissipates seismic energy with external dampers, which is widely used in bridge engineering.

[0003] However, the traditional related construction methods have many shortcomings: the prestressed duct grouting is prone to uneven density and insufficient sealing performance, leading to corrosion of the prestressed tendons or loss of prestress, affecting the durability of the structure; the installation and positioning accuracy of the external dampers is low, the assembly is complicated, and the replacement is not convenient in the later period, making it difficult to quickly respond to the structure maintenance requirements; there is a lack of real-time monitoring and feedback mechanism for the prestress state, grouting quality and damper assembly effect during the construction process, which cannot timely discover construction hidden dangers and dynamically adjust construction parameters; the coordination between the construction links is poor, the segment jointing accuracy, the rationality of the connection between prestress tensioning and grouting is insufficient, further affecting the stability and reliability of the overall structure of the pier.

[0004] Therefore, it is necessary to design a full-prestressed duct grouting external damper pier construction method to solve the problems of insufficient density and sealing of duct grouting, inconvenient installation and maintenance of external dampers, and poor coordination between construction links in traditional construction technology. SUMMARY

[0005] In view of this, the present application provides a full-prestressed duct grouting external damper pier construction method, which aims to solve the problems of insufficient density and sealing of duct grouting, inconvenient installation and maintenance of external dampers, and poor coordination between construction links in traditional construction technology.

[0006] In one aspect, the present application provides a full-prestressed duct grouting external damper pier construction method, comprising: Select a single bundle of prestressed tendons as longitudinal prestressed steel strands, wrap a sealing sleeve on the outer surface of the prestressed tendons, and install sealing plugs that fit the prestressed tendons at both ends of the sleeve to form a single bundle of sealed prestressed tendon assemblies; at the same time, lay out the steel reinforcement framework and build a mold, fix a hollow sealing channel pipe material at the preset position of the steel reinforcement framework, and the hollow sealing channel pipe material is used to pass through the longitudinal prestressed steel strands; set a channel interface reserved structure at the preset position of the mold before pouring, and remove the mold after curing the concrete to a preset strength to form a prefabricated pier segment, wherein the top of each segment except the top segment is provided with a shear key, and the bottom of each segment except the bottom segment is provided with a key groove matched with the shear key; The prefabricated segment is hoisted by hoisting equipment through the shear key and the key groove, and the end face positioning pin hole of the prefabricated segment is aligned with the next segment positioning pin and inserted into the auxiliary fixing, and then the whole bridge pier is hoisted in sequence; one end of the single-bundle sealed prestressed tendon assembly is inserted through the interface at one end of the built-in sealed passage of the bridge pier and is pulled out from the other end, the tensioning equipment is installed at both ends of the single-bundle sealed prestressed tendon assembly, a preset tension is applied to a preset stress value, the longitudinal prestressed tendon is kept in a preset tensioning state, and the sealed anchor plate is installed at the interfaces at both ends of the passage and is fixed by bolts; after the sealed anchor plate locks the stress state of the prestressed tendon assembly, the hollow sealed passage pipe is grouted; During the prefabrication of the bridge pier, a fastener with a connecting hole at the exposed end is embedded, the connecting seat is fixed with the connecting hole of the fastener through bolts, then the external energy dissipation damper is inserted into the installation slot of the connecting seat, and the assembly is completed by clamping the external energy dissipation damper into the clamping slot through the built-in buckle in the connecting seat. A data acquisition device is connected to the detection port on the side of the connecting seat, and the acquisition device is used to acquire stress data of the prestressed tendon assembly and position data of the damper and the connecting seat.

[0007] Further, when the prefabricated bridge pier segment and the prestressed tendon assembly are prepared, the method comprises: The inner wall of the hollow sealed passage pipe is coated with an elastic sealing layer material, and the coating thickness is uniform and covers the entire area of the inner wall of the pipe, and the inner diameter of the hollow sealed passage pipe is matched with the diameter of the longitudinal prestressed tendon. The sealing sleeve of the single-bundle sealed prestressed tendon assembly is tightly attached to the outer surface of the prestressed tendon, a sealing lip is arranged on the inner circle of the sealing plug at both ends of the sealing sleeve, and the sealing lip forms an interference fit with the surface of the prestressed tendon.

[0008] Further, when the bridge pier segment and the prestressed tendon are connected, the method comprises: Before the bridge pier segment is connected, the shear key, the key groove, the positioning pin and the positioning pin hole are cleaned. A sealing gasket is arranged between the contact surface of the sealing anchor plate and the bridge pier segment, and the sealing gasket is compressed and deformed after the anchor plate bolts are tightened.

[0009] Further, when the damper is installed and the construction data is collected, the method comprises: The embedded fastener is welded and fixed with the steel reinforcement framework during the prefabrication of the bridge pier, the inner wall of the connecting hole at the exposed end of the fastener is provided with internal threads, and the bolts are used to fix the connecting seat. When the external energy dissipation damper is inserted into the connecting seat installation slot, the connecting seat is provided with a built-in buckle structure, the buckle structure is configured to have an automatic ejection function, the gap between the buckle after ejection and the external energy dissipation damper clamping slot on the side is controlled within a preset range, and the external energy dissipation damper can be replaced by detaching the buckle and the bolts. The data acquisition device accesses the detection port, and real-time acquisition of prestressed tendon assembly stress data and damper and connecting seat fit position data is performed, and a preset acquisition frequency is set, and the acquired data is stored synchronously to a data terminal.

[0010] Further, when grouting the prestressed duct, the method comprises: a standard value of compressive strength, a standard value of fluidity, and a setting time range of the high-performance concrete grouting material are preset, the standard value of compressive strength is greater than or equal to a design strength grade, the standard value of fluidity is greater than or equal to a preset limit value, and the setting time range is that initial setting is greater than or equal to a preset time length and final setting is less than or equal to a preset time length; The pressure grouting equipment is used to inject the grouting material from one end of the duct, the grouting pressure is controlled in a preset pressure range, an air vent is arranged at the other end to discharge air, and until the air vent continuously discharges the grouting material without air bubbles; After the grouting is completed, curing is performed for a preset curing time, and after the curing is completed, the grouting compactness is detected, and the measured compactness is compared with a preset compactness threshold value: When the measured compactness is greater than or equal to the preset threshold value, it is determined that the grouting is qualified; When the measured compactness is less than the preset threshold value, the hole is cleaned again and the grouting is performed for a second time until it is qualified.

[0011] Further, when detecting the fitting accuracy of the shear key and the key groove, the method comprises: a maximum allowed fitting gap of the shear key and the key groove and a key side fit degree threshold value are preset, the maximum allowed fitting gap is less than or equal to a preset fitting gap millimeter value, and the key side fit degree threshold value is greater than or equal to a preset fit degree percentage; After the segment butt joint is completed, a feeler gauge is used to detect the gap value of the shear key and the key groove, and a fit degree detection tool is used to detect the key side fit area ratio; The measured gap value, the maximum allowed fitting gap, the measured fit degree, and the fit degree threshold value are compared: When the measured gap value is less than or equal to the maximum allowed fitting gap and the measured fit degree is greater than or equal to the fit degree threshold value, it is determined that the fitting is qualified; When any of the following conditions is met, the segment position is adjusted or the key groove is ground, the butt joint is detected again until the measured gap value is less than or equal to the maximum allowed fitting gap and the measured fit degree is greater than or equal to the fit degree threshold value: the measured gap value is greater than the maximum allowed fitting gap or the measured fit degree is less than the fit degree threshold value.

[0012] Further, when controlling the tensioning accuracy of the longitudinal prestressed steel tendon, the method comprises: a tensioning stress deviation allowed range and a tensioning rate interval are preset, the stress deviation allowed range is ± a preset percentage, and the tensioning rate interval is a preset rate interval; Real-time monitoring of the actual stress value and tension rate of each bundle of prestressed steel strand during tensioning, calculating the deviation rate of the actual stress from the preset stress value; When the deviation rate is within the allowable range and the tension rate is within the preset rate interval, continue tensioning to the preset stress value; When the deviation rate exceeds the allowable range, pause tensioning and adjust the tensioning equipment parameters; When the tension rate exceeds the preset rate interval, continue tensioning after adjusting the rate to ensure that the final stress value meets the requirements.

[0013] Further, when replacing the external energy dissipation damper, including: Pre-set damper disassembly sequence, installation positioning reference line, the installation positioning reference line coincides with the center line of the connecting seat installation slot; When disassembling, loosen the buckle and bolt according to the preset sequence, remove the old damper and clean the connecting seat installation slot; When installing the new damper, align the positioning reference line and insert it into the installation slot to ensure that the buckle automatically pops out and clamps tightly, and the tightening torque of the bolt reaches the preset value; After installation is completed, detect the fit clearance and fastness of the damper and the connecting seat, and when the clearance is less than or equal to the preset value and the fastness is qualified, determine that the replacement is qualified; When the clearance is greater than the preset value or the fastness is not qualified, reinstall until the clearance is less than or equal to the preset value and the fastness is qualified.

[0014] Further, when processing abnormal data of the data acquisition device, including: Pre-set stress data fluctuation threshold, and adhesion position data drift allowable range, the drift allowable range is ± preset drift millimeters; Real-time monitoring of collected data, when the stress data fluctuation is greater than or equal to the stress data fluctuation threshold or the adhesion position data drift exceeds the data drift allowable range, determine that the data is abnormal; First, check the connection state of the acquisition device and the detection port, if the connection is loose, then re-plug and fix; If the connection is normal, calibrate the acquisition device and re-collect data; If the calibration is still abnormal after multiple times, replace the acquisition device and supplement the data to ensure data continuity.

[0015] Further, when the overall acceptance after construction is completed, including: Pre-set acceptance indicators and qualified standards, the acceptance indicators include prestressed steel strand stress value, hole grouting density, damper installation precision, and segment docking flatness, and the corresponding qualified standards are respectively stress value within the preset range, density greater than or equal to the preset threshold, installation precision less than or equal to the preset deviation, and flatness less than or equal to the preset millimeter; Each index was tested using a stress tester, a grout density tester, a precision measuring instrument, and a flatness testing tool. When all acceptance indicators meet the qualification standards, the overall construction is deemed qualified. If any indicator fails to meet the standard, a rectification plan is formulated, and the inspection is repeated until all indicators meet the standard.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. This construction method, through the continuous single-strand design of longitudinal prestressed steel strands, ensures the uniformity and integrity of prestress transfer and provides a stable self-resetting driving force for the piers under seismic action, significantly reducing residual displacement and repair difficulty. The precise fit between the shear keys and matching keyways of the precast segments not only significantly improves the shear resistance between segments and resists the risk of slippage under lateral loads, but also enhances the fit and overall structural integrity, enabling each segment to form a collaborative force-bearing system, effectively avoiding damage caused by localized stress concentration, and comprehensively improving the bearing stability and deformation resistance of the piers.

[0017] 2. External energy dissipation dampers offer significant advantages: During strong earthquakes, they can efficiently dissipate seismic energy through their own deformation, reducing the impact on the main pier and protecting core components from irreversible damage; made of zinc-aluminum alloy, they possess excellent corrosion resistance, resisting harsh environmental erosion without the need for additional anti-corrosion coatings, reducing construction costs and subsequent maintenance workload; simultaneously, through the combination of built-in clips and bolts in the connecting seat, the dampers can be easily installed and quickly replaced. After a strong earthquake, damaged or degraded dampers can be replaced without disassembling the main pier, significantly reducing operation and maintenance difficulty and costs, and ensuring the continuity of bridge operation.

[0018] 3. The single-strand sealed prestressing tendon assembly, combined with the sealing anchor plate, forms a fully enclosed protective system. This avoids the risk of corrosion caused by direct contact between the prestressing tendon and the grouting material, and also prevents grout leakage and runoff during grouting, ensuring dense and uniform grouting in the ducts and reducing prestress loss. The real-time data acquisition device on the side of the connecting seat fills the gap in traditional construction lacking monitoring and feedback, and can promptly detect potential problems such as prestress fluctuations and loose damper assembly, providing data support for dynamic adjustment of construction parameters and subsequent structural health monitoring. In addition, the collaborative design of prefabricated segment factory production and precise on-site docking shortens the construction cycle, reduces on-site construction difficulty, and achieves a comprehensive improvement in structural performance, construction efficiency, and operational safety, significantly extending the long-term service life of the bridge piers. Attached Figure Description

[0019] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings: Figure 1 A flowchart illustrating the construction method of a bridge pier with a fully prestressed duct grouting and external damper provided in an embodiment of the present invention. Detailed Implementation

[0020] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the disclosure to those skilled in the art. It should be noted that, unless otherwise specified, embodiments and features in the embodiments of the present invention can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0021] Reference Figure 1 In some embodiments of this application, a construction method for a bridge pier with a fully prestressed duct grouting external damper includes the following steps: Step S100: Select a single prestressed tendon as the longitudinal prestressed steel tendon, install a sealing sleeve on its outer surface, and install sealing plugs that fit the prestressed tendon at both ends of the sleeve to form a single-strand sealed prestressed tendon assembly; at the same time, lay out the steel reinforcement skeleton and build a mold, fix a hollow sealing channel pipe at the preset position of the steel reinforcement skeleton, the hollow sealing channel pipe is used to pass through the longitudinal prestressed steel tendon; before pouring, set a channel interface reserved structure at the preset position of the mold, pour concrete and cure to the preset strength, then remove the mold to form a precast pier segment. In the precast pier segment, except for the top segment, each segment is provided with a shear key at the top, and except for the bottom segment, each segment is provided with a keyway matching the shear key at the bottom; Step S200: Using hoisting equipment, the precast segments are connected to the keyway via shear keys. At the same time, the positioning pin holes on the end face of the precast segments are aligned with the positioning pins of the next segment and inserted for auxiliary fixation. The segments are hoisted sequentially to form an integral pier. One end of the single-strand sealed prestressed tendon assembly is passed through one end interface of the pier's built-in sealed channel and out from the other end. Tensioning equipment is installed at both ends of the single-strand sealed prestressed tendon assembly to apply a preset tension to the preset stress value. The longitudinal prestressed steel strands are kept in a preset tension state. Seal anchor plates with bolts are installed at both ends of the channel interface. After the sealing anchor plates lock the stress state of the prestressed tendon assembly, the hollow sealed channel pipe is grouted. Step S300: During the prefabrication stage of the bridge pier, pre-embed the fastener with the exposed end with the connection hole. After fixing the connecting seat to the fastener connection hole with the bolt, align the external energy dissipation damper with the mounting groove of the connecting seat and insert it. The assembly is completed by snapping the external energy dissipation damper into the slot of the external energy dissipation damper through the built-in buckle of the connecting seat. Step S400: Connect a data acquisition device to the detection port on the side of the connector. The acquisition device is used to collect stress data of the prestressed tendon assembly and contact position data of the damper and the connector.

[0022] The above embodiments, through the continuous single-strand design of longitudinal prestressed steel strands, not only ensure the uniformity and integrity of prestress transfer, but also provide a stable self-resetting driving force for the piers under seismic action, significantly reducing residual displacement and repair difficulty. The precise fit between the shear keys and matching keyways of the precast segments not only significantly improves the shear resistance between segments and resists the risk of slippage under lateral loads, but also enhances the fit and overall structural integrity, enabling each segment to form a collaborative force-bearing system, effectively avoiding damage caused by localized stress concentration, and comprehensively improving the bearing stability and deformation resistance of the piers. External energy dissipation dampers offer significant advantages: during strong earthquakes, they can efficiently dissipate seismic energy through their own deformation, reducing the impact on the main pier and protecting core components from irreversible damage; made of zinc-aluminum alloy, they possess excellent corrosion resistance, resisting harsh environmental erosion without the need for additional anti-corrosion coatings, thus reducing construction costs and subsequent maintenance workload; simultaneously, through the combination of built-in clips and bolts in the connecting seat, the dampers can be easily installed and quickly replaced, allowing for replacement of damaged or degraded dampers without disassembling the main pier after a strong earthquake, significantly reducing operation and maintenance difficulty and costs, and ensuring the continuity of bridge operation. The single-strand sealed prestressing tendon assembly, combined with the sealing anchor plate, forms a fully enclosed protective system. This avoids the risk of corrosion caused by direct contact between the prestressing tendon and the grouting material, and also prevents grout leakage and runoff during grouting, ensuring dense and uniform grouting in the ducts and reducing prestress loss. The real-time data acquisition device on the side of the connecting seat fills the gap in traditional construction lacking monitoring and feedback, and can promptly detect potential problems such as prestress fluctuations and loose damper assembly, providing data support for dynamic adjustment of construction parameters and subsequent structural health monitoring. In addition, the collaborative design of prefabricated segment factory production and precise on-site docking shortens the construction cycle, reduces on-site construction difficulty, and achieves a comprehensive improvement in structural performance, construction efficiency, and operational safety, significantly extending the long-term service life of the bridge piers.

[0023] Specifically, the prefabrication of bridge pier segments and the preparation of prestressed tendon assemblies include: The hollow sealed channel pipe has an elastic sealing layer material coated on its inner wall. The coating thickness is uniform and covers the entire inner wall area of ​​the pipe. The inner diameter of the hollow sealed channel pipe is adapted to the diameter of the longitudinal prestressed steel strand. The sealing sleeve of the single-strand sealed prestressed tendon assembly is tightly fitted to the outer surface of the prestressed tendon. The inner ring of the sealing plug at both ends of the sealing sleeve is provided with a sealing lip, and the sealing lip forms an interference fit with the surface of the prestressed tendon.

[0024] Specifically, the hollow sealed channel pipe is made of high-strength corrosion-resistant material (such as modified PVC, stainless steel, or glass fiber reinforced plastic). Its inner wall needs to be sandblasted to remove rust and cleaned and degreased before being coated with an elastic sealing layer material (preferably silicone sealant or butyl rubber, which has the characteristics of aging resistance, tensile strength, and compatibility with grouting material). The coating thickness is controlled at 1-2mm and a spiral coating process is used throughout to ensure no missed coating or dripping, and to completely cover the inner wall of the pipe and the edges of both ends. The inner diameter of the hollow sealed channel pipe is 2-5mm larger than the diameter of the longitudinal prestressed steel strands, which not only meets the requirements for smooth steel strand installation, but also leaves a reasonable gap for grouting material filling. At the same time, the straightness error of the pipe is ≤0.5mm / m to avoid steel strand tension obstruction or incomplete grouting due to pipe bending. The sealing sleeve of the single-strand sealed prestressed tendon assembly is made of high-density polyethylene or polytetrafluoroethylene (with wear resistance, aging resistance, and chemical corrosion resistance). The wall thickness is set at 3-5mm to ensure structural strength. The sleeve length is 100-150mm longer than the actual length of the prestressed steel strand used to reserve space for tensioning and anchoring operations. The sealing sleeve and the outer surface of the prestressed tendon are tightly bonded using a heat-shrink bonding process, eliminating gaps such as air bubbles and wrinkles. The sealing plug is made of hard, wear-resistant rubber and is integrally molded. The inner ring has 2-3 annular sealing lips (the lip cross-section is wedge-shaped). The interference between the lip and the surface of the prestressed tendon is controlled at 0.3-0.5mm to ensure a tight seal while avoiding excessive interference that could damage the surface of the prestressed tendon during tensioning. At the same time, the connection between the sealing plug and the sealing sleeve is fixed by hot-melt welding to prevent the plug from falling off due to pressure during grouting.

[0025] The above embodiments, through the uniform and complete coverage of the elastic sealing layer on the inner wall of the hollow sealing channel pipe, combined with the inner diameter of the pipe adapted to the diameter of the longitudinal prestressed steel strands, and the tight fit between the sealing sleeve and the prestressing tendon, and the interference fit between the inner sealing lip of the sealing plug and the prestressing tendon, form a multi-layer sealing protection system. This effectively blocks the leakage of grout and the intrusion of external moisture, preventing the corrosion of the prestressing tendon, and ensuring the smooth installation of the prestressing tendon and the stability of the tensioning process. At the same time, it reserves a reasonable gap for grouting in the duct, ensuring that the grout filling is dense and uniform, reducing prestress loss, and significantly improving the integrity of prestress transfer and the long-term durability of the pier structure.

[0026] Specifically, when connecting bridge pier segments to tensioned prestressed tendons, the following applies: Before connecting the bridge pier segments, the shear keys, keyways, locating pins and locating pin holes are cleaned. A sealing gasket is sandwiched between the sealing anchor plate and the contact surface of the pier segment. The sealing gasket is compressed and deformed after the anchor plate bolts are tightened.

[0027] Specifically, before the pier segments are joined, a combination of high-pressure air blowing and wire brush grinding is used to clean the mating surfaces of the shear keys and keyways, as well as the inner walls of the locating pins and locating pin holes. This thoroughly removes any concrete residue, oil, rust, and dust adhering to the surfaces. After cleaning, the surfaces are wiped clean with a dry cloth to ensure that there are no visible impurities or moisture residue on the contact surfaces. At the same time, the burrs on the edges of the shear keys are ground down, and the straightness of the locating pins (error ≤ 0.3 mm / m) and the roundness of the locating pin holes (tolerance ≤ ± 0.2 mm) are checked. If any deformation or damage is found, it must be repaired in time to avoid affecting the joining accuracy. The sealing anchor plate is integrally formed from high-strength alloy steel plate. Its contact surface with the pier segment is mechanically polished, with a surface roughness controlled at Ra1.6-3.2μm to ensure a tight fit. The sealing gasket is made of nitrile rubber or fluororubber, resistant to aging and grout corrosion, with a thickness of 3-5mm. The outer diameter of the gasket is 10-15mm larger than the contact surface of the anchor plate, and its inner diameter matches the inner diameter of the channel interface. A through hole is pre-drilled on the gasket to precisely correspond to the bolt holes on the anchor plate. During installation, first precisely attach the sealing gasket to the end face of the pier segment interface, then align the sealing anchor plate with the channel interface and bolt holes. Use a torque wrench to tighten the bolts in a symmetrical and even sequence, controlling the tightening torque at 80- 120 N·m is used to compress the sealing gasket to 30%-50% of its own thickness, forming a reliable seal. Before tensioning the prestressing tendons, the overall axial deviation of each segment after docking is checked (allowable deviation ≤3mm / segment). After passing the test, the synchronous tensioning process at both ends is adopted, following the procedure of "pre-tensioning (10% of design stress) → graded tensioning (20% of design stress per grade) → holding and stabilizing the load (holding the load for 5 minutes per grade) → final tensioning (holding the load for 10 minutes after reaching the design stress)". During the tensioning process, the stress change of the prestressing tendons and the segment displacement are monitored in real time through a data acquisition device to ensure that the stress deviation is controlled within ±3% and to avoid structural deformation caused by uneven local stress.

[0028] The above embodiments effectively remove impurities and burrs from the contact surfaces by cleaning the shear keys, keyways, locating pins, and locating pin holes before the pier segments are joined. This ensures the fitting accuracy and positioning precision of the segments, enhances the shear resistance of the shear keys, and improves the overall stress coordination of the segments. Simultaneously, the sealing gaskets sandwiched between the sealing anchor plate and the pier segment contact surface undergo reasonable compression deformation after the bolts are tightened, forming a tight and reliable sealing structure. This not only prevents grout leakage and external moisture intrusion to protect the prestressing tendons but also improves the stability of the anchor plate fixation. Combined with a standardized tensioning process, this ensures accurate and stable prestress transfer, reduces stress loss, and comprehensively improves the sealing performance, structural integrity, and long-term load-bearing reliability of the pier segment connections.

[0029] Specifically, the installation of dampers and the collection of construction data include: The pre-embedded fasteners are welded and fixed to the steel reinforcement cage during the prefabrication stage of the bridge pier. The inner wall of the connection hole at the exposed end of the fastener is provided with internal thread, and the bolt is used to fix the connecting seat. When the external energy dissipation damper is inserted into the mounting slot of the connector, the connector has a built-in snap-fit ​​structure. The snap-fit ​​structure is configured to have an automatic pop-out function. After the snap-fit ​​pops out, the gap between the snap-fit ​​and the side external energy dissipation damper slot is controlled within a preset range. The external energy dissipation damper can be replaced by disassembling the snap-fit ​​and bolts. After the data acquisition device is connected to the detection port, it collects stress data of the prestressed tendon assembly and data on the contact position between the damper and the connecting seat in real time, presets the acquisition frequency, and stores the acquired data synchronously to the data terminal.

[0030] Specifically, the embedded fasteners are made of high-strength carbon steel or stainless steel, with specifications matching the fixing requirements of the connector. They are welded to the reinforcing steel frame using a double-sided fillet weld process, with a weld height ≥ 8mm and a length ≥ 1.5 times the fastener diameter. After welding, rust removal and anti-corrosion treatment is performed (applying epoxy zinc-rich primer + topcoat). During embedding, the fastener position is fixed using positioning fixtures to ensure that the center line of the exposed end connection hole is perpendicular to the connector mounting reference surface, with a positioning deviation ≤ ±0.5mm. The exposed length of the fastener is 5-8mm longer than the thickness of the connector, leaving space for bolt installation adjustment. The internal thread of the exposed end connection hole of the fastener uses fine-pitch threads (1.5-2mm pitch). After thread machining, metal shavings are cleaned from the teeth, and a thread protective sleeve is used for protection to prevent cement slurry from seeping in and clogging the threads during concrete pouring. The outer shell and connecting seat of the external energy dissipation damper are both integrally die-cast from zinc-aluminum alloy. The inner wall of the mounting slot of the connecting seat is precision ground, with dimensional tolerance controlled within ±0.2mm. The slot opening is equipped with a 15° guide chamfer to facilitate damper insertion. The internal buckle of the connecting seat is a spring-driven structure with a rounded transition design at the buckle head. The pop-out stroke is 2-3mm. The mating gap between the buckle and the damper slot is preset to 0.1-0.3mm to ensure a tight fit without affecting the normal energy dissipation deformation of the damper. When inserting the damper into the mounting slot, it should be pushed smoothly along the guide chamfer until the buckle automatically pops out and locks into the slot with a locking sound. Then, M12-M16 high-strength bolts are used to pass through the connecting seat and the fastener connection hole for fixation. The bolt tightening torque is controlled within 60-90N・m. When replacing the damper, insert a tool through the unlocking hole reserved on the side of the connecting seat, press the buckle to unlock, and then loosen the bolt to remove the damper. The entire process does not require disassembling the main structure of the bridge pier. The data acquisition device includes a high-precision stress sensor (measurement accuracy ±0.5%FS) and a displacement sensor (resolution 0.01mm). The sensors are fixed to the detection port via threaded connections, and the connection points are wrapped with PTFE tape to ensure a seal and prevent moisture damage. The acquisition frequency is preset to 10-50Hz and can be dynamically adjusted according to the construction stage (high-frequency acquisition during tensioning and low-frequency acquisition during maintenance). Data transmission adopts a wired + wireless dual-mode design (wired transmission ensures stability during construction, while wireless transmission facilitates remote monitoring). The acquired data is synchronized in real time to a local data terminal (storage capacity ≥1TB) and a cloud server. The terminal has a built-in data anomaly threshold judgment module. When stress fluctuations exceed ±5% of the design value or the mating position drift exceeds ±1mm, an audible and visual alarm is automatically triggered. The acquisition device has an IP67 protection rating, making it suitable for harsh outdoor environments such as high and low temperatures, rain, and snow. The sensor probes are treated with a corrosion-resistant coating to extend their service life.

[0031] The above embodiments, through the secure welding of pre-embedded fasteners to the steel reinforcement cage and the internal thread design of the exposed end, ensure accurate and reliable installation of the connector. Combined with the connector's built-in automatic pop-out buckle and preset fitting gap, this enables convenient assembly and rapid replacement of the external energy-dissipating damper without disassembling the pier body. Simultaneously, the data acquisition device collects real-time data on prestressed tendon stress and damper contact position. Through preset acquisition frequency and synchronous storage, it promptly captures parameter anomalies during construction and operation, providing accurate data support for structural condition monitoring and maintenance decisions. This not only improves the stability and ease of maintenance of the damper installation but also ensures real-time controllability of the pier structure's stress, extending the overall structural lifespan and operational safety.

[0032] In a specific embodiment of this application, the above steps are implemented in the following ways: Both the precast pier segments and prestressed tendon assemblies are produced in a standardized factory. The steel reinforcement cage is CNC machined according to the design drawings and positioned using a jig to ensure that the spacing deviation of the steel reinforcement is ≤±5mm. The hollow sealed channel pipes are fixed in the preset position of the steel reinforcement cage using special clamps (spacing ≤1.5m) to ensure that the parallelism error between the pipe axis and the design axis of the pier is ≤1mm / m. Steel formwork is used for the molds. After installation, the verticality (error ≤0.3% of the formwork height) and sealing performance are checked. Pumped concrete is used for pouring (pouring speed 0.5-1m / h) in conjunction with an immersion vibrator (vibration spacing ≤500mm). To avoid under-vibration or over-vibration, concrete is steam-cured (temperature 20-30℃, humidity ≥90%) until it reaches 85% or more of its design strength before demolding. After demolding, the dimensions of shear keys, keyways, and channel interfaces are checked (tolerance ≤±2mm). Once qualified, they are marked and stored. Before on-site construction, the hoisting site is leveled and steel plates are laid. A truck crane or crawler crane with a rated lifting capacity ≥80t is selected. Four-point lifting devices (sling angle ≥60°) are used to hoist precast segments weighing ≤50t per segment. During connection, deviations are monitored in real time using a laser rangefinder. After axis alignment, positioning pins are inserted and the stability is checked by hammering. Before tensioning, the hydraulic tensioning machine is calibrated (error ≤ ±2%). Tensioning is completed according to the standard procedure. Grouting is performed using a high-pressure grouting pump (pressure 0.5-1.0MPa). A designated person monitors the grout discharge from the vent hole. After no air bubbles are detected, the vent hole is closed and the pressure is stabilized for 3-5 minutes. The prestressing tendons must not be disturbed within 24 hours after grouting. The embedded fasteners are fixed to the inner wall of the mold using positioning fixtures welded from steel profiles to ensure accurate embedding. Before installing the connector, the fastener connection holes are cleaned and thread-locking agent is applied to the bolts. The external energy dissipation damper is transported in a special protective box and installed by two construction workers in coordination. The slot is pushed in until the buckle pops out and locks. After installation, gently tap to check for looseness and abnormal noise. Multiple dampers are installed in the order of "symmetrical installation, inside first, then outside". Before installing the data acquisition device, the sensor is zero-point calibrated. When connecting the detection port, wrap 3-5 turns of PTFE tape to seal and prevent moisture. The local data terminal is installed in the bridge management room. The cloud server is connected to the bridge health monitoring platform. The acquisition frequency is set to 50Hz during the construction phase and adjusted to 10Hz during the operation phase. The data terminal is equipped with a daily automatic backup function (backup retention ≥1 year). Abnormal alarm information is pushed to relevant personnel via SMS and platform to ensure timely handling.

[0033] The above scenarios are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

[0034] Specifically, grouting of prestressed ducts includes: The standard values ​​for compressive strength, fluidity, and setting time of the high-performance concrete grout are preset. The standard value for compressive strength is greater than or equal to the design strength grade, the standard value for fluidity is greater than or equal to the preset limit, and the setting time range is that the initial setting time is greater than or equal to the preset time and the final setting time is less than or equal to the preset time. The grouting material is injected from one end of the duct using a pressure grouting device. The grouting pressure is controlled within a preset pressure range. An air vent is provided at the other end to discharge air until the air vent continuously discharges grouting material without air bubbles. After grouting is completed, curing is carried out for the preset curing time. After curing, the grout density of the duct is tested, and the measured density is compared with the preset density threshold. When the measured density is greater than or equal to the preset threshold, the grouting is deemed qualified. When the measured density is less than the preset threshold, the hole is cleaned again and grouting is performed a second time until it is qualified.

[0035] Specifically, when testing the fit accuracy between the shear key and the keyway, the following steps are included: The maximum allowable fit gap between the preset shear key and the keyway, and the key side fit threshold, wherein the maximum allowable fit gap is less than or equal to the preset fit gap in millimeters, and the key side fit threshold is greater than or equal to the preset fit percentage; After the segmental connection is completed, the gap between the shear key and the keyway is measured using a feeler gauge, and the fit tester is used to measure the percentage of the key side fit area. Compare the measured gap value with the maximum allowable fit gap, and the measured fit degree with the fit threshold: When the measured gap value is less than or equal to the maximum allowable fit gap and the measured fit degree is greater than or equal to the fit threshold, the fit is deemed qualified. When either the measured gap value is greater than the maximum allowable fit gap or the measured fit degree is less than the fit degree threshold, adjust the segment position or grind the keyway, and re-connect and test until the measured gap value is less than or equal to the maximum allowable fit gap and the measured fit degree is greater than or equal to the fit degree threshold.

[0036] Specifically, controlling the tensioning accuracy of longitudinal prestressed steel strands includes: The allowable range of tension stress deviation and the tension rate range are preset. The allowable range of stress deviation is ± a preset percentage, and the tension rate range is a preset rate range. During the tensioning process, the actual stress value and tensioning rate of each prestressed steel strand are monitored in real time, and the deviation rate between the actual stress and the preset stress value is calculated. When the deviation rate is within the allowable range and the tensioning rate is within the preset rate range, continue tensioning to the preset stress value; When the deviation rate exceeds the allowable range, tensioning is paused and the tensioning equipment parameters are adjusted; When the tensioning rate exceeds the preset rate range, adjust the rate and continue tensioning to ensure that the final stress value meets the requirements.

[0037] Specifically, replacing the external energy dissipation damper includes: The damper disassembly sequence and installation positioning reference line are preset, and the installation positioning reference line coincides with the center line of the connecting seat mounting groove. During disassembly, loosen the clips and bolts in the preset sequence, remove the old damper, and clean the mounting groove of the connector. When installing a new damper, align it with the positioning reference line and insert it into the mounting slot, ensuring that the clips automatically pop out and lock in place, and that the bolt tightening torque reaches the preset value. After installation, check the fit clearance and fixing firmness between the damper and the connecting seat. If the clearance is less than or equal to the preset value and the firmness is qualified, it is determined to be qualified for replacement. If the gap is greater than the preset value or the firmness is not up to standard, reinstall until the gap is less than or equal to the preset value and the firmness is up to standard.

[0038] Specifically, when processing abnormal data from the data acquisition device, the following are included: The preset stress data fluctuation threshold and the allowable drift range of the bonding position data are defined as ± a preset drift in millimeters. Real-time monitoring of collected data; when stress data fluctuation is greater than or equal to the stress data fluctuation threshold or when the data drift at the bonding position exceeds the allowable range of data drift, the data is judged to be abnormal. First, check the connection status between the data acquisition device and the detection port. If the connection is loose, re-plug and secure it. If the connection is normal, calibrate the data acquisition device and reacquire data. If the problem persists after multiple calibrations, replace the data acquisition device and collect additional data to ensure data continuity.

[0039] Specifically, the overall acceptance inspection after construction is completed includes: The pre-set acceptance indicators and qualification standards include the prestressed steel strand stress value, duct grouting density, damper installation accuracy, and segment joint flatness. The corresponding qualification standards are: stress value within a preset range, density greater than or equal to a preset threshold, installation accuracy less than or equal to a preset deviation, and flatness less than or equal to a preset number of millimeters. Each index was tested using a stress tester, a grout density tester, a precision measuring instrument, and a flatness testing tool. When all acceptance indicators meet the qualification standards, the overall construction is deemed qualified. If any indicator fails to meet the standard, a rectification plan is formulated, and the inspection is repeated until all indicators meet the standard.

[0040] Understandably, by pre-setting the material properties and construction parameters for prestressed duct grouting, employing pressure grouting and density testing and secondary grouting for assurance, setting standards for the precision of shear key and keyway fit and adjusting them through actual measurement and grinding, setting the deviation range and rate interval for longitudinal prestressed steel strand tensioning and monitoring and adjusting them in real time, setting the disassembly sequence and positioning baseline for the replacement of external energy dissipation dampers and ensuring their qualification through installation testing, setting thresholds for abnormal data acquisition and ensuring data continuity through investigation, calibration and replacement, and setting comprehensive acceptance indicators and qualification standards after construction and conducting testing, rectification and re-inspection, precise control of each key construction link, closed-loop quality management and convenient and efficient operation and maintenance have been achieved in all aspects. This effectively avoids problems such as insufficient grouting density, insufficient shear resistance of segment joints, prestress loss, damper replacement affecting the main structure, data monitoring failure and overall construction quality substandard, significantly improving the construction quality, load-bearing stability, seismic reliability and long-term operational safety of the bridge pier structure, while reducing construction and subsequent operation and maintenance costs.

[0041] In a specific embodiment of this application, the above steps are implemented in the following ways: Applicable to highway and railway bridge projects in high-intensity earthquake areas, coastal high-corrosion environments, and across rivers and seas, etc., where strict requirements are imposed on the construction quality, structural stability and seismic performance of bridge piers, especially suitable for the standardized construction and later operation and maintenance scenarios of segment precast and assembled bridge piers; specifically in implementation, first preset the parameters of high-performance concrete grout for prestressed duct grouting (compressive strength standard value ≥ C60, fluidity standard value ≥ 300mm, initial setting ≥ 4h, final setting ≤ 12h), use a high-pressure grouting pump to inject from one end of the duct, control the grouting pressure at 0.5 - 1.0MPa, stop when the non-bubbling grout continuously discharges from the exhaust hole at the other end, perform standard curing for 7d after grouting, use an ultrasonic detector to detect the density after curing, and determine it as qualified if the measured value ≥ 95%, and if unqualified, clean the hole and grout again; when detecting the matching accuracy of shear keys and key grooves, preset the maximum allowable matching clearance ≤ 2mm and the key side fitting degree threshold ≥ 90%, use a 0.02 - 1mm feeler gauge to measure the clearance and a laser scanning detector to detect the proportion of the fitting area after segment docking, and if any index is unqualified, adjust the segment position or grind the key groove, and re-dock and detect until qualified; when controlling the tensioning accuracy of longitudinal prestressed steel tendons, preset the allowable range of stress deviation ± 3% and the tensioning rate interval 0.1 - 0.2MPa / s, monitor in real time through stress sensors and displacement gauges during the tensioning process, and pause and adjust when the deviation rate or rate exceeds the range to ensure that the final stress value meets the design requirements; when replacing the external energy-dissipating damper, operate according to the preset sequence of "loosen the bolts first and then unlock the buckles", use a laser alignment instrument to calibrate the positioning reference line that coincides with the center line of the mounting groove of the connecting seat, clean the mounting groove after removing the old damper, align the new damper with the reference line and insert it until the buckle automatically pops out and locks tightly, tighten the bolts to a torque of 60 - 90N・m, use a feeler gauge to measure the matching clearance (≤ 0.3mm) and a torque wrench to check the firmness after installation, and if unqualified, reinstall; when processing abnormal data of the data acquisition device, preset the stress data fluctuation threshold ± 5% of the design value and the allowable range of drift of the fitting position data ± 1mm, first check the connection status of the detection port after detecting an abnormality, re-plug and fix if loose, calibrate the device if the connection is normal, replace the device and supplement the data of the previous 1h if still abnormal after multiple calibrations to ensure data continuity; when conducting the overall acceptance after construction, preset the acceptance indicators and qualified standards covering the stress value of prestressed steel tendons (within ± 3% of the design value), the grouting density of the duct (≥ 95%), the installation accuracy of the damper (deviation ≤ 0.5mm), and the flatness of segment docking (≤ 3mm / m), use a stress detector, a grouting density detector, a precision measuring instrument, and a flatness detection tool to detect respectively, determine it as qualified if all indicators are qualified, and if any indicator is unqualified, formulate a targeted rectification plan (such as supplementary grouting, grinding the key groove, adjusting the installation position of the damper), and re-accept after rectification until all are qualified.

[0042] The above scenarios are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

[0043] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program goods. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program goods embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0044] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program goods according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0045] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0046] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0047] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A construction method of a full prestressed duct grouting external damper pier, characterized in that, The application relates to a prefabricated bridge pier and a construction method thereof. The application comprises the following steps: a single-beam prestressed tendon is selected as a longitudinal prestressed steel tendon, a sealing sleeve is sleeved on the outer surface of the single-beam prestressed tendon, and sealing plugs which are matched with the single-beam prestressed tendon are arranged at both ends of the sealing sleeve, so that a single-beam sealing prestressed tendon assembly is formed; meanwhile, a steel tendon skeleton is arranged and a mold is built, a hollow sealing channel pipe is fixed at a preset position of the steel tendon skeleton, and the hollow sealing channel pipe is used for penetrating the longitudinal prestressed steel tendon; a channel interface reserved structure is arranged at the preset position of the mold before pouring, the poured concrete is cured to a preset strength, and then the mold is removed, so that a prefabricated bridge pier segment is formed, and a shear key is arranged at the top of each segment except the top segment, and a key groove matched with the shear key is arranged at the bottom of each segment except the bottom segment; The prefabricated segment is hoisted by hoisting equipment, the shear key is butted with the key groove, and a positioning pin hole of the prefabricated segment is aligned with a positioning pin of the next segment; then the prefabricated segment is hoisted to form an integral bridge pier; one end of the single-beam sealing prestressed tendon assembly is penetrated through one end of a built-in sealing channel of the bridge pier and is penetrated out from the other end, a tensioning device is arranged at both ends of the single-beam sealing prestressed tendon assembly, a preset tension is applied to a preset stress value, the longitudinal prestressed steel tendon is kept in a preset tensioning state, sealing anchor plates fixed by bolts are arranged at both ends of the channel, the stress state of the prestressed tendon assembly is locked by the sealing anchor plates, and the hollow sealing channel pipe is grouted; During the prefabrication of the bridge pier, a fastener with a connecting hole at an exposed end is pre-buried, a connecting seat is fixed to the connecting hole of the fastener through bolts, an external energy dissipation damper is inserted into a mounting groove of the connecting seat, and assembly is completed by clamping the external energy dissipation damper into a clamping groove of the connecting seat through a clamping buckle arranged in the connecting seat. A data acquisition device is connected to a detection port on the side of the connecting seat, and the acquisition device is used for acquiring stress data of the prestressed tendon assembly and position data of the damper and the connecting seat.

2. The construction method of a full-prestressed duct grouting external damper pier according to claim 1, characterized in that, When the prefabricated bridge pier segment and the prestressed tendon assembly are prepared, the following steps are included: An elastic sealing layer material is coated on the inner wall of the hollow sealing channel pipe, and the coating thickness is uniform and covers the entire area of the inner wall of the pipe; the inner diameter of the hollow sealing channel pipe is matched with the diameter of the longitudinal prestressed steel tendon; The sealing sleeve of the single-beam sealing prestressed tendon assembly is tightly matched with the outer surface of the prestressed tendon, a sealing lip is arranged on the inner ring of the sealing plug at both ends of the sealing sleeve, and the sealing lip is in interference fit with the surface of the prestressed tendon.

3. The construction method of a full-prestressed duct grouting external damper pier according to claim 1, characterized in that, When the bridge pier segments are butted and the prestressed tendon is tensioned, the following steps are included: Before the bridge pier segments are butted, the shear key, the key groove, the positioning pin and the positioning pin hole are cleaned; A sealing gasket is clamped between the contact surface of the sealing anchor plate and the bridge pier segment, and the sealing gasket is compressed and deformed after the bolts of the anchor plate are tightened.

4. The construction method of a full-prestressed duct grouting external damper pier according to claim 1, characterized in that, When the damper is installed and the construction data is acquired, the following steps are included: The pre-buried fastener is welded and fixed to the steel tendon skeleton during the prefabrication of the bridge pier, an inner thread is arranged on the inner wall of the connecting hole at the exposed end of the fastener, and the bolts are used for fixing the connecting seat; When the external energy dissipation damper is inserted into the mounting groove of the connecting seat, a clamping buckle structure is arranged in the connecting seat, the clamping buckle structure is configured to have an automatic ejection function, the gap between the clamping buckle after ejection and the clamping groove of the external energy dissipation damper is controlled within a preset range, and the external energy dissipation damper can be replaced by detaching the clamping buckle and the bolts; The data acquisition device accesses the detection port, and real-time acquisition of prestressed tendon assembly stress data and damper and connecting seat fitting position data is performed, and a preset acquisition frequency is set, and the acquired data is stored synchronously to a data terminal.

5. The construction method of full-prestressed duct grouting external damper pier according to claim 1 or 3, characterized in that, When grouting the prestressed duct, the method comprises: presetting a compressive strength standard value, a fluidity standard value and a setting time range of the high-performance concrete grouting material, the compressive strength standard value is greater than or equal to a design strength grade, the fluidity standard value is greater than or equal to a preset limit value, and the setting time range is that initial setting is greater than or equal to a preset time length and final setting is less than or equal to a preset time length; the grouting material is injected from one end of the duct by using a pressure grouting device, the grouting pressure is controlled within a preset pressure range, an exhaust hole is arranged at the other end to exhaust air, and until the exhaust hole continuously exhausts the grouting material without air bubbles; after grouting is completed, maintenance is performed for a preset maintenance time length, and after maintenance is completed, the duct grouting compactness is detected, and the measured compactness is compared with a preset compactness threshold value: when the measured compactness is greater than or equal to the preset threshold value, it is determined that the grouting is qualified; when the measured compactness is less than the preset threshold value, the duct is cleaned and grouted again until it is qualified.

6. The construction method of a full-prestressed duct grouting external damper pier according to claim 1 or 3, characterized in that, When the fitting accuracy of the shear key and the key groove is detected, the method comprises: presetting a maximum allowed fitting gap of the shear key and the key groove and a key side fitting degree threshold value, the maximum allowed fitting gap is less than or equal to a preset fitting gap millimeter value, and the key side fitting degree threshold value is greater than or equal to a preset fitting degree percentage; after the segments are butt-jointed, a feeler gauge is used to detect the gap value of the shear key and the key groove, and a fitting degree detection tool is used to detect the key side fitting area percentage; the measured gap value is compared with the maximum allowed fitting gap, and the measured fitting degree is compared with the fitting degree threshold value: when the measured gap value is less than or equal to the maximum allowed fitting gap and the measured fitting degree is greater than or equal to the fitting degree threshold value, it is determined that the fitting is qualified; when any of the following conditions is met, the segment position is adjusted or the key groove is ground, the butt joint is detected again until the measured gap value is less than or equal to the maximum allowed fitting gap and the measured fitting degree is greater than or equal to the fitting degree threshold value: the measured gap value is greater than the maximum allowed fitting gap or the measured fitting degree is less than the fitting degree threshold value.

7. The construction method of a full-prestressed duct grouting external damper pier according to claim 1 or 3, characterized in that, When controlling the tensioning accuracy of the longitudinal prestressed steel strand, the method comprises: presetting a tensioning stress deviation allowed range and a tensioning rate range, the stress deviation allowed range is ± a preset percentage, and the tensioning rate range is a preset rate range; during tensioning, the actual stress value and the tensioning rate of each prestressed steel strand are monitored in real time, and the deviation rate of the actual stress from the preset stress value is calculated; when the deviation rate is within the allowed range and the tensioning rate is within the preset rate range, tensioning continues until the preset stress value is reached; when the deviation rate exceeds the allowed range, tensioning is paused and the tensioning equipment parameters are adjusted; when the tensioning rate exceeds the preset rate range, tensioning continues after the rate is adjusted to ensure that the final stress value meets the requirements.

8. The construction method of a full-prestressed duct grouting external damper pier according to claim 4, characterized in that, When replacing the external energy dissipation damper, the method comprises: presetting a damper dismounting sequence and an installation positioning reference line, the installation positioning reference line is coincident with the center line of the connecting seat installation groove; during dismounting, the buckles and bolts are loosened in the preset sequence, the old damper is taken out and the connecting seat installation groove is cleaned; during installation of the new damper, the installation groove is inserted in alignment with the positioning reference line, it is ensured that the buckles are automatically ejected and clamped, and the tightening torque of the bolts reaches a preset value; After installation, detect the fit clearance and fastening firmness of the damper and the connecting seat. If the clearance is less than or equal to the preset value and the fastening firmness is qualified, determine that the replacement is qualified; If the clearance is greater than the preset value or the fastening firmness is unqualified, reinstall until the clearance is less than or equal to the preset value and the fastening firmness is qualified. 9.The full-prestressed duct grouting external damper pier construction method according to claim 4, characterized in that, When handling abnormal data of the data collection device, the method comprises: Pre-set stress data fluctuation threshold and fitting position data drift allowable range, the drift allowable range is ± preset drift millimeter number; Real-time monitoring of collected data, when the stress data fluctuation is greater than or equal to the stress data fluctuation threshold or the fitting position data drift exceeds the data drift allowable range, determine that the data is abnormal; First, check the connection state of the collection device and the detection port. If the connection is loose, re-plug and fix; If the connection is normal, calibrate the collection device and re-collect data; If the calibration is still abnormal after multiple times, replace the collection device and supplement the data to ensure data continuity.

10. The construction method of a full-prestressed duct grouting external damper pier according to claim 1, characterized in that, When the overall acceptance after construction is completed, the method comprises: Pre-set acceptance index and qualified standard, the acceptance index includes prestressed steel strand stress value, hole grouting compactness, damper installation precision, segment docking flatness, and the corresponding qualified standards are stress value in the preset range, compactness greater than or equal to the preset threshold, installation precision less than or equal to the preset deviation, and flatness less than or equal to the preset millimeter number; Use stress detector, grouting compactness detector, precision measuring instrument and flatness detection tool to detect each index respectively; When all acceptance indexes meet the qualified standard, determine that the overall construction is qualified; When any index is unqualified, develop a rectification scheme, and re-accept after rectification until all indexes are qualified.

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