A method for repairing and reinforcing a water pier of a bridge in a tidal area

Abstract

The application discloses a low-cost and safe maintenance and reinforcement method for a tidal zone bridge underwater pier, which comprises the following steps: steel sleeve box cofferdam installation, sacrificial anode protection system installation and pier column concrete reinforcement. When the steel sleeve box cofferdam installation step is performed, first, the lower inner support is fixed on the top surface of the pile cap by means of implanting anchor bolts, then the side plate of the steel sleeve box cofferdam is connected with the lower inner support, and then the hydraulic jack pushes the water stop belt working platform until the GINA water stop belt is closely combined with the side surface of the pile cap; when the sacrificial anode protection system installation step is performed, the zinc block with a front electric potential sequence is arranged on the corroded steel bar of the pier column as a sacrificial anode to protect the iron steel bar with a rear electric potential sequence; when the pier column concrete reinforcement step is performed, the gasket is arranged between the inner side surface of the glass fiber reinforced plastic formwork and the outer surface of the pier column, and the mortar is sealed on the outer edge of the bottom opening of the glass fiber reinforced plastic formwork, and the RPC concrete is poured after the mortar reaches a certain strength.

Description

TECHNICAL FIELD

[0001] The present application relates to a method for repairing and reinforcing a water pier of a bridge in a tidal area. BACKGROUND

[0002] With the rapid development of modern highways, urban expressways and other large traffic, there are more and more bridges across rivers, across rivers and across seas. These bridges facilitate people's traffic while the load on the pier is increasing year by year. The foundation of the pier has shown signs of disease. In particular, the cross-sea bridge with navigation requirements, the pier is eroded by seawater in the tidal area, and the pier is eroded by seawater in the tidal area. The combined action of adverse factors such as ship impact or scratching, disease is particularly serious, including rust expansion, concrete damage, ship impact marks, and the connection between the pile cap and the pier, which has a large safety hazard, so it is necessary to take repair and reinforcement measures for the pier. The lower structure of the cross-sea bridge includes pile foundation, pile cap and pier column. The repair and reinforcement of the lower structure is different from the construction of the lower structure of the newly-built bridge. The repair and reinforcement construction is limited by the factors of bridge clearance, existing structures, seawater tides and navigation requirements, etc., which increases the construction difficulty of the repair and reinforcement work. SUMMARY

[0003] The purpose of the present application is to overcome the defects of the prior art and provide a method for repairing and reinforcing a water pier of a bridge in a tidal area, which has the characteristics of low cost and safety, can effectively alleviate the corrosion of the steel bars on the water pier, and prolong the service life of the pier structure.

[0004] The purpose of the present application is achieved by a method for repairing and reinforcing a water pier of a bridge in a tidal area, using a bottomless steel sleeve box cofferdam for water construction, and comprising the following steps: water pile cap finishing, steel sleeve box cofferdam installation, steel sleeve box cofferdam sealing, sacrificial anode protection system installation, pier column concrete reinforcement and steel sleeve box cofferdam removal;

[0005] When the water pile cap finishing step is performed, divers use a high-pressure water gun to clean the top surface and side surface of the pile cap to ensure that the pile cap surface is flat and the side surface is free of accumulated silt;

[0006] When the steel box cofferdam installation step is performed, the steel box cofferdam has a rectangular plan and is a bottomless steel box, and the inner wall of the steel box cofferdam is sequentially provided with a lower inner support, a middle coffering purlin and an upper coffering purlin from bottom to top; the inside bottom surface of the lower inner support is connected with an anchoring steel plate; the outer end of the lower inner support is connected with a corbel fixed on the side plate of the steel box cofferdam, and the corbel and the lower inner support are connected through a flange; the bottom of each of the four side plates of the steel box cofferdam is provided with a water stop belt working platform, the water stop belt working platform is arranged in a guide groove formed by a pressing plate and a bottom plate, and the inner end of the water stop belt working platform is provided with an installation groove for embedding a GINA water stop belt, and a plurality of hydraulic jacks are arranged at intervals between the outer end of the water stop belt working platform in the guide groove and the side wall of the steel box cofferdam; when the steel box cofferdam is installed, first, a surveyor measures and lays out the position of the lower inner support of the steel box cofferdam on the top surface of the pile cap in combination with the tidal difference, then a rebar planting hole is formed on the top surface of the pile cap according to the layout, and the rebar planting hole is filled with epoxy resin rebar glue, then an anchor bolt connected with the anchoring steel plate of the lower inner support is inserted into the rebar planting hole, the lower inner support is fixed on the top surface of the pile cap after the epoxy resin rebar glue is cured, then the corbel on the side plate of the steel box cofferdam is connected with the corresponding lower inner support through a flange bolt, and finally the water stop belt working platforms are synchronously pressed from the outside of the water stop belt working platforms, the water stop belt working platforms are pushed towards the pile cap along the guide groove until the GINA water stop belt is tightly attached to the side surface of the pile cap;

[0007] When the water stopping step is performed, first, the communication holes on the steel box cofferdam are blocked, then water is pumped out to form a dry working environment;

[0008] When the sacrificial anode protection system installation step is performed, a zinc block with a front electric potential is arranged on the corroded steel bar of the pier column as a sacrificial anode to protect the ferrous steel bar with a rear electric potential, and a sacrificial anode protection system is established, including the following procedures:

[0009] ①The concrete at the rust expansion and spalling position of the pier column is chipped off to expose the steel bars, and the exposed steel bars are derusted and treated against rust;

[0010] ②A plurality of galvanized flat irons are electrically connected at intervals on the exposed steel bars, the ends of the galvanized flat irons are inserted below the designed low water level, a zinc block is installed on the end of each galvanized flat iron by means of a bolt, and then the zinc blocks are electrically connected in series;

[0011] When the pier column concrete reinforcement step is performed, including the following procedures:

[0012] ①The loose mortar on the concrete surface of the pier column in the steel box cofferdam is removed, and the unfirm attachments and harmful pollutants are removed, the surface of the reinforced part is chiseled or manually treated, and the chiseling depth is at least more than 10 mm;

[0013] ②The permanent glass fiber reinforced plastic formwork is hoisted by the artificial and crawler crane in blocks, the cross-sectional size of the glass fiber reinforced plastic formwork is larger than that of the pier column, and the gaskets are arranged between the inner side of the glass fiber reinforced plastic formwork and the outer surface of the pier column; after the glass fiber reinforced plastic formwork is fixed, the outer edge of the bottom opening of the glass fiber reinforced plastic formwork is sealed by the mortar, and the RPC concrete is poured after the mortar reaches a certain strength;

[0014] ③The RPC concrete is prepared by mixing the silica powder, cement, special RPC admixture, water and additive, and the poured RPC concrete is poured within 30 minutes after mixing; the components are continuously poured, and the maximum interval time is not more than 6 minutes; the concrete is covered and watered after pouring, and the watering time is not less than 7 days;

[0015] When the steel sleeve cofferdam dismantling step is performed, the pressure applied on the water stop belt working platform is released, the seawater is allowed to enter the steel sleeve cofferdam, the bolt connection between the four side plates of the steel sleeve cofferdam is released by the crawler crane and the divers underwater, and the unit side plates are removed in pieces.

[0016] The above-mentioned pier column maintenance and reinforcement method for the bridge in the tidal area, wherein when the steel sleeve cofferdam installation step is performed, the four side plates of the steel sleeve cofferdam adopt double-wall structure, each side plate is formed by two unit side plates connected by high-strength bolts, and a rubber water stop plate is arranged on the joint surface of each two unit side plates; each unit side plate comprises an inner side steel plate, an outer side steel plate, and a horizontal stiffener and a vertical bulkhead plate connected between the inner side steel plate and the outer side steel plate; an operating platform is arranged on the top of the steel sleeve cofferdam in a ring shape, and a ladder is arranged for the construction personnel to enter and exit.

[0017] The above-mentioned pier column maintenance and reinforcement method for the bridge in the tidal area, wherein when the steel sleeve cofferdam installation step is performed, the water stop belt working platform is made of stainless steel, and a Teflon plate is arranged between the top surface of the water stop belt working platform and the pressing plate of the guide groove and between the bottom surface of the water stop belt working platform and the bottom plate of the guide groove.

[0018] The above-mentioned pier column maintenance and reinforcement method for the bridge in the tidal area, wherein when the steel sleeve cofferdam installation step is performed, the position of the side plate of the steel sleeve cofferdam is fine-tuned by the hand-operated hoist, the accurate positioning of the side plate is performed through the guide hole and the circular truncated cone guide rod pre-installed on the flange joint surface between the corbel and the lower inner support, and then the flange bolt is fastened; and the top opening of the side plate is fixed on the clamp pre-installed on the pier column by the temporary channel steel.

[0019] The above-mentioned pier column maintenance and reinforcement method for the bridge in the tidal area, wherein when the pier column concrete reinforcement step is performed, the RPC concrete is poured by pressure grouting, one pressure grouting pipe is arranged on each of the four sides of the pier column, the pouring is performed in a symmetrical order, and the pressure balance around the glass fiber reinforced plastic formwork is ensured.

[0020] The maintenance and reinforcement method for the underwater pier of the tidal zone bridge pier of the present application has the following characteristics:

[0021] 1) The extensible water stop belt working platform composed of GINA water stop belt and hydraulic jack is adopted, the pressure of the jack is applied to the water stop belt working platform, the sealing effect between the steel sleeve cofferdam and the pile cap is achieved, the seawater is prevented from entering the steel sleeve cofferdam, the dry operation environment is provided for the repair of the pier column, and the original pile cap is used as the construction operation platform, the steel sleeve cofferdam bottom plate is saved, and the cost investment is reduced;

[0022] 2) The lower inner support of the double-wall steel sleeve box is fixed on the pile cap by implanting anchor bolts on the top surface of the pile cap, and the anchor bolts are implanted in the anchor hole filled with epoxy resin anchor glue; the upper side plate of the steel sleeve cofferdam adopts two surrounding purlins as the inner support, so that the bottom of the steel sleeve cofferdam is not on the seabed, a full-section construction environment is provided for the pier column, the interference of the steel support attached to the pier column is reduced, and the construction is more convenient;

[0023] 3) The sacrificial anode (zinc) in front of the potential sequence is arranged on the original bridge pier corroded steel bar to protect the steel bar (iron) behind the potential sequence, a sacrificial anode protection system is established, the corrosion of the steel bar is effectively alleviated, and the service life of the pier column is improved;

[0024] 4) A layer of RPC concrete is added on the outer surface of the original pier column, the diseases on the underwater pier column in the tidal zone are effectively repaired, the corrosion of the steel bar of the underwater pier column by seawater is effectively reduced, and the service life of the bridge pier is prolonged. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1 is the longitudinal elevation view of the steel sleeve cofferdam adopted by the maintenance and reinforcement method for the underwater pier of the tidal zone bridge pier of the present application;

[0026] Figure 2 is the transverse elevation view of the steel sleeve cofferdam adopted by the maintenance and reinforcement method for the underwater pier of the tidal zone bridge pier of the present application;

[0027] Figure 2a is Figure 2 A-A view in

[0028] Figure 2b is Figure 2 B-B view in

[0029] Figure 2c is Figure 2 C-C view in

[0030] Figure 2d is Figure 2 D-D view in

[0031] Figure 3 isFigure 2 Enlarged view of the middle P site;

[0032] Figure 4 is a structural schematic view when the steel box cofferdam installation step of the method of the present application is performed;

[0033] Figure 5 is another structural schematic view when the steel box cofferdam installation step of the method of the present application is performed;

[0034] Figure 5a is a top view of Figure 5 ;

[0035] Figure 6 is a structural schematic view when the sacrificial anode protection system installation step of the method of the present application is performed;

[0036] Figure 7 is a structural schematic view when the pier concrete reinforcement step of the method of the present application is performed;

[0037] Figure 7a is an E-E view of Figure 7 ; DETAILED DESCRIPTION

[0038] The present application will be further described below in conjunction with the accompanying drawings.

[0039] Referring to Figures 1 to 7a , the method for repairing and reinforcing a water pier of a tidal zone bridge of the present application adopts a bottomless steel box cofferdam to perform water-enclosing construction, and includes the following steps: water pier cap trimming, steel box cofferdam installation, steel box cofferdam water sealing, sacrificial anode protection system installation, pier concrete reinforcement, and steel box cofferdam removal.

[0040] When the water pier cap trimming step is performed, divers clean the top surface and side surface of the cap using a high-pressure water gun, to ensure that the cap surface is flat and the side surface is free of accumulated silt;

[0041] When the steel box cofferdam installation step is performed, the plane of the steel box cofferdam 100 is rectangular and corresponds to the plane structure of the pile cap 301 and is a bottomless steel box; the four side plates 10 of the steel box cofferdam 100 are all double-wall structures, and each side plate 10 is formed by splicing two unit side plates by M20 high-strength bolts, and a 1cm-thick rubber waterstop plate is arranged on the splicing surface of each two unit side plates; each unit side plate includes an inner side plate, an outer side plate, and a horizontal stiffener and a vertical bulkhead plate connected between the inner side plate and the outer side plate; the top of the steel box cofferdam 100 is provided with an operating platform in a ring shape, and a ladder is arranged for the construction personnel to enter and exit; the inner wall of the steel box cofferdam 100 is sequentially provided with a lower inner support 101, a middle cofferdam purlin 102, and an upper cofferdam purlin 103 from bottom to top; wherein the inner bottom surface of the lower inner support 101 is connected with an anchoring steel plate 10A, the rear end of the lower inner support 101 is connected with a corbel 11 fixed on the side plate 10, and the corbel 11 and the lower inner support 101 are connected by a flange 12; the bottom of each side plate 10 of the steel box cofferdam is provided with a waterstop belt working platform 200, and the waterstop belt working platform 200 is arranged in a guide groove, the guide groove is composed of a pressing plate 201 fixed on the inner side of the side plate 10 of the steel box cofferdam and a bottom plate 202, and the inner end of the waterstop belt working platform 200 is provided with a mounting groove for embedding the GINA waterstop belt 20; the waterstop belt working platform 200 is made of stainless steel, and four fluorine plates are arranged between the top surface of the waterstop belt working platform 200 and the pressing plate 201 of the guide groove and between the bottom surface of the waterstop belt working platform 200 and the bottom plate 202 of the guide groove, so that the waterstop belt working platform 200 can smoothly slide in the guide groove; a plurality of hydraulic jacks 30 are arranged between the outer end of the waterstop belt working platform 200 in the guide groove and the side wall 101 of the steel box cofferdam at intervals;

[0042] In the installation of the steel box cofferdam, first, the position of the lower inner support 101 of the steel box cofferdam 100 is measured and laid out on the top surface of the pile cap 301 by a surveyor in combination with the tidal difference, then the anchor hole is drilled on the top surface of the pile cap 301 according to the layout, and the anchor hole is filled with epoxy resin anchor glue, then the φ20 anchor bolt 10B connected with the anchoring steel plate 10A of the lower inner support 101 is inserted into the anchor hole, and after the epoxy resin anchor glue is cured, the lower inner support 101 is fixed on the top surface of the pile cap 301, then the bracket 11 on the side plate 10 of the steel box cofferdam 100 is connected with the corresponding lower inner support 101 through the flange bolts, finally, the hydraulic jack 30 outside the water stop working platform 200 is used to press the water stop working platform 200 synchronously, the water stop working platform 200 is pushed along the guide groove towards the pile cap 301 until the GINA water stop 20 is tightly attached to the side surface of the pile cap 301, and the joint between every two GINA water stops 20 is filled with rubber blocks; the bottom of the four side plates 10 of the steel box cofferdam 100 is symmetrically tensioned with two φ32 fine rolled threaded steels 104 to enhance the connection performance of the bottom of the steel box cofferdam 100; when the side plate 10 of the steel box cofferdam is installed, the hand-operated hoist is used to fine-tune the position of the side plate 10, the side plate 10 is accurately positioned through the guide hole 13 and the circular truncated cone guide rod 14 pre-installed on the flange butt joint surface between the bracket 11 and the lower inner support 101, and then the flange bolts are fastened; to prevent the side plate 10 from overturning, the temporary channel steel 15 at the top of the side plate 10 is fixed on the hoop 16 pre-installed on the pier column 302;

[0043] When the water stopping step of the steel box cofferdam is performed, first, the communication hole on the steel box cofferdam 100 is blocked, then the water is pumped out to form a dry working environment;

[0044] When the sacrificial anode protection system installation step is performed, the zinc block 42 in front of the potential sequence is used as a sacrificial anode to protect the ferrous steel bar 40 behind the potential sequence, a sacrificial anode protection system is established, the corrosion of the steel bar is effectively alleviated, and the service life of the structure is improved, including the following procedures:

[0045] ①The concrete at the rust expansion and spalling position of the pier column 302 is chipped off to expose the steel bar 40, and the exposed steel bar 40 is derusted and treated against rust;

[0046] ②The exposed steel bar 40 is electrically connected with a plurality of galvanized flat irons 41 at intervals, the tail end of the galvanized flat iron 41 extends below the designed low water level, a zinc block 42 is installed on the tail end of each galvanized flat iron 41 through a bolt, and then the plurality of zinc blocks 42 are electrically connected in series;

[0047] When the pier concrete reinforcement step is performed, including the following procedures:

[0048] ①Remove the weak mortar on the concrete surface of the pier 302 in the steel box cofferdam 100, remove the weak adhesion and harmful pollutants, reinforce the surface by chiseling machine or manual chiseling, the chiseling depth is at least 10mm or more to ensure the effective bonding of the RPC concrete and the structure base surface;

[0049] ②Use manual and crawler crane to hoist the permanent glass steel formwork 50 in blocks, the cross-sectional size of the glass steel formwork 50 is 10cm larger than that of the pier 302; the inner side of the glass steel formwork 50 is provided with a spacer 51 between the outer surface of the pier 302, the thickness of the spacer 51 is 5cm; the glass steel formwork 50 is locked by fastening bolt 52 after being embraced by two plane U-shaped formwork components; after the glass steel formwork 50 is fixed, the bottom opening outer edge of the glass steel formwork 50 is sealed by mortar, and after the mortar reaches a certain strength, the RPC concrete is poured to avoid bottom leakage;

[0050] ③The RPC concrete is mixed by silica powder, cement, RPC special admixture, water and additive, and the mixed RPC concrete is poured within 30min after mixing; the components are continuously poured, and the maximum interval time is not more than 6min; after the concrete pouring is completed, the covering and watering maintenance is used for not less than 7d;

[0051] The RPC concrete is poured by using the grouting construction equipment; since the pouring state of the RPC concrete is the thick and viscous cement slurry, the planar structure of the pier 302 is rectangular, and the flowability of the RPC concrete at the corner of the pier 302 is poor, therefore, one grouting pipe is arranged on each side of the pier 302, and the pouring is performed in a symmetrical order to ensure the pressure balance around the glass steel formwork 50;

[0052] When the steel box cofferdam is removed, the pressure applied on the water stop belt working platform 200 is released first, the seawater enters the steel box cofferdam 100 to balance the internal and external pressure, and then the 50T crawler crane is used to cooperate with the diver to remove the bolt connection between the four side plates 10 of the steel box cofferdam 100 in pieces, and the unit side plates are removed in pieces.

[0053] The above examples are only used to illustrate the present application, and are not limited to the present application. Those skilled in the art can make various changes or modifications without departing from the spirit and scope of the present application, therefore, all equivalent technical solutions should belong to the scope of the present application, which should be limited by the claims.

Claims

1. A method for repairing and reinforcing bridge piers in tidal zones, comprising the following steps: (The method involves using a bottomless steel cofferdam for water containment construction.) The underwater pier cap repair, steel cofferdam installation, steel cofferdam water sealing, sacrificial anode protection system installation, pier column concrete reinforcement, and steel cofferdam dismantling are characterized by the following: During the underwater foundation repair process, divers use high-pressure water guns to clean the top and sides of the foundation to ensure that the surface is flat and there is no silt or sand buildup on the sides. During the installation of the steel cofferdam, the steel cofferdam has a rectangular plan and is a bottomless steel cofferdam. The inner wall of the steel cofferdam is sequentially equipped with a lower inner support, a middle waler, and an upper waler from bottom to top. Anchor steel plates are connected to the inner bottom surface of the lower inner support. The outer end of the lower inner support is connected to a corbel fixed to the side plate of the steel cofferdam, and the corbel is connected to the lower inner support via a flange. A waterstop working platform is provided at the bottom of each of the four side plates of the steel cofferdam. The waterstop working platform is located in a guide groove formed by a pressure plate and a bottom plate, and the inner end of the waterstop working platform has an installation groove for embedding the GINA waterstop. Multiple hydraulic jacks are spaced apart between the outer end of the waterstop working platform in the guide groove and the side wall of the steel cofferdam. When installing the steel cofferdam, the surveyor first measures and lays out the position of the lower inner support of the steel cofferdam on the top surface of the pier, taking into account the tidal difference. Then, anchoring holes are opened on the top surface of the pier according to the layout, and epoxy resin anchoring adhesive is filled into the anchoring holes. Then, the anchor bolts connected to the anchoring steel plates of the lower inner support are inserted into the anchoring holes. After the epoxy resin anchoring adhesive cures, the lower inner support is fixed on the top surface of the pier. Then, the corbels on the side plates of the steel cofferdam are connected to the corresponding lower inner supports with flange bolts. Finally, the hydraulic jacks on the outside of the waterstop working platform are used to apply pressure to the waterstop working platform, pushing the waterstop working platform along the guide groove towards the pier until the GINA waterstop is tightly attached to the side of the pier. When carrying out the water-stopping step, first seal the connecting holes on the steel cofferdam, then pump out the water to create a dry working environment; When installing a sacrificial anode protection system, zinc blocks with a higher potential sequence are placed on the corroded reinforcing bars of the pier as sacrificial anodes to protect the iron reinforcing bars with a lower potential sequence. The sacrificial anode protection system includes the following steps: ① Remove the rusted and spalled concrete from the pier column to expose the reinforcing steel bars, and then remove and prevent rust from the exposed steel bars. ② Connect several galvanized flat irons at intervals to the exposed steel bars. The ends of the galvanized flat irons extend below the designed low water level. Then, install zinc blocks at the ends of each galvanized flat iron with bolts. Finally, connect several zinc blocks together electrically. The following procedures are included in the concrete reinforcement of pier columns: ① Remove loose mortar from the concrete surface of the piers inside the steel cofferdam, remove loose attachments and harmful pollutants, and roughen the surface of the reinforced part with a roughening machine or manually, with a roughening depth of at least 10mm. ② The permanent fiberglass formwork is hoisted in sections by manual labor and crawler cranes. The cross-sectional dimensions of the fiberglass formwork are larger than those of the pier column. Spacers are placed between the inner side of the fiberglass formwork and the outer surface of the pier column. After the fiberglass formwork is fixed, mortar is used to seal the outer edge of the bottom opening of the fiberglass formwork. RPC concrete is poured after the mortar reaches a certain strength. ③ RPC concrete is made of silica fume, cement, RPC special admixture, water and additives. The RPC concrete should be poured within 30 minutes after mixing. The components should be poured continuously, with a maximum interval of no more than 6 minutes. After the concrete is poured, it should be covered and watered for curing for no less than 7 days. When carrying out the dismantling of the steel cofferdam, first release the pressure applied to the working platform of the waterstop to allow seawater to enter the steel cofferdam. Then, use a crawler crane in conjunction with divers to disconnect the bolt connections between the four side plates of the steel cofferdam underwater, and dismantle the unit side plates one by one.

2. The method for repairing and reinforcing bridge piers in tidal zones according to claim 1, characterized in that, During the installation of the steel cofferdam, all four side panels of the steel cofferdam adopt a double-wall structure, and each side panel is composed of two unit side panels spliced ​​together by high-strength bolts. A rubber waterstop is installed on the splicing surface of every two unit side panels. Each unit side panel includes an inner steel plate, an outer steel plate, and a transverse stiffening plate and a vertical bulkhead connecting the inner and outer steel plates. An operating platform is set around the top of the steel cofferdam, and a ladder is provided for construction personnel to enter and exit.

3. The method for repairing and reinforcing bridge piers in tidal zones according to claim 1, characterized in that, When installing the steel cofferdam, the waterstop working platform is made of stainless steel, and PTFE plates are provided between the top surface of the waterstop working platform and the pressure plate of the guide groove, as well as between the bottom surface of the waterstop working platform and the bottom plate of the guide groove.

4. The method for repairing and reinforcing bridge piers in tidal zones according to claim 1, characterized in that, When installing the steel cofferdam, use a hand-operated hoist to fine-tune the position of the side plates of the steel cofferdam. The side plates are precisely positioned by using the guide holes and frustum-shaped guide rods pre-set on the flange mating surface connecting the corbel and the lower inner support. Then, tighten the flange bolts. Finally, use temporary channel steel to fix the top of the side plates to the clamps pre-installed on the pier.

5. The method for repairing and reinforcing bridge piers in tidal zones according to claim 1, characterized in that, When reinforcing the pier column with concrete, the RPC concrete is injected using pressure grouting. A pressure grouting pipe is arranged on each of the four sides of the pier column, and the grouting is carried out in a symmetrical order to ensure pressure balance around the fiberglass formwork.

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