Dock and wharf comprehensive repair construction method

Abstract

The invention provides a dock and wharf comprehensive repair construction method, belongs to the technical field of repair construction, and is suitable for dock and wharf engineering repair which is long in service life and serious in structure corrosion and damage. According to the method, a series of technical problems such as abrasion of a bottom plate of an old dock, corrosion of a dock wall, failure of a pull rod, damage of a dock structure and the like are solved through systematic construction measurement and deformation monitoring, divided dock structure repairing, dock dredging and structure reinforcing, floating dock construction and supporting facility repairing; efficient and safe repair of the old port hydraulic structure is achieved, the overall bearing capacity of the structure is improved, and the service life is prolonged. The construction process is clear, all procedures are closely connected, the whole deformation monitoring process is controlled, construction is safe, the repairing process is high in pertinence, and the method is suitable for repairing projects similar to coastal old docks and wharfs.

Description

Technical Field

[0001] This invention belongs to the field of repair and construction technology, specifically relating to a comprehensive repair and construction method for docks and wharves, applicable to the repair of dock and wharf projects with long service life and severe structural corrosion and damage. Background Technology

[0002] Dock and wharf projects are subject to multiple factors such as seawater immersion, tidal erosion, ship collisions, and atmospheric corrosion over long periods of time. After decades of service, they are prone to various structural damage problems: the concrete of the dock floor slab has peeled off and exposed rocks; the dock walls are vertical anchored steel sheet pile structures with rusted and reduced diameter of the tie rods and missing threads; rust buildup on the steel sheet piles makes them prone to falling off; mooring bollards, rubber fenders, and other auxiliary facilities have aged and failed; the tugboat trolley tracks have deformed and pulled off; the wharf area has siltation, structural cracks, and concrete damage; the steel pipe piles of the piers are severely corroded; and the revetment retaining walls, pump rooms, and power rooms, among other supporting facilities, have also suffered varying degrees of structural damage.

[0003] The existing renovation and construction of old docks and wharves suffers from numerous technical deficiencies: a lack of systematic construction surveying and full-process deformation monitoring systems makes it easy for structural displacement to exceed safety thresholds during construction, leading to collapse risks; the large pouring height of dock walls makes direct pouring prone to concrete segregation and formwork deformation, affecting construction quality; the lack of standardized extension and anchoring techniques for tie rod repairs leads to uneven stress and insufficient load-bearing capacity due to traditional methods; poor adhesion between new and old concrete surfaces during base slab repairs, resulting in secondary cracking; and independent construction of each repair process, leading to chaotic process connections, low construction efficiency, and insufficient control over disturbance to surrounding hydraulic structures.

[0004] Meanwhile, many regions have strict standards and specifications for building surveying and construction (such as SLA land surveying standards, SS560:2016, SS580:2012, etc.). Existing repair methods are difficult to meet local construction standards and safety requirements. There is an urgent need for a comprehensive repair and construction method that is suitable for old coastal docks and piers, complies with Singapore construction specifications, and takes into account construction safety, quality and efficiency. Summary of the Invention

[0005] This invention addresses the technical deficiencies of existing old dock and wharf repair construction methods. Combining local engineering construction specifications, it provides a comprehensive repair construction method for docks and wharves, enabling safety monitoring and quality control throughout the construction process. It solves the repair problems of core structures such as dock walls, bottom plates, and tie rods, optimizes the construction process and connection flow of each procedure, and improves the construction efficiency of the repair project as well as the overall load-bearing capacity and durability of the repaired structure.

[0006] The present invention employs the following technical solution.

[0007] A method for comprehensive repair and construction of docks and wharves, comprising: Step 1: Conduct measurements and deformation monitoring for the comprehensive repair work of the dock and pier; Step 2: After measurement and deformation monitoring, carry out dock structure repair; Step 3: After the dry dock structure repair is completed, the dock construction will commence; Step 4: After the dock construction is completed, the floating dock construction will proceed; Step 5: After the floating dock construction is completed, the supporting facilities will be repaired; Step 6: After repairing the supporting facilities, install the electromechanical and fire protection facilities.

[0008] Preferably, step 1 specifically includes: Step 1-1: Based on local land surveying standards and local surveyor specifications, a qualified local unit shall set up a primary control network and establish a horizontal and vertical control network. Steps 1-2: Conduct on-site construction layout according to the construction design, set up monitoring points, and complete the installation of deep soil displacement monitoring points before the dock is pumped out. Steps 1-3: Conduct full-process deformation monitoring during the dewatering of the dock, record the displacement data of deep soil in real time, and suspend work for rectification when the displacement of the monitoring point exceeds the warning value. After the dewatering is completed, continue monitoring until the displacement tends to stabilize.

[0009] Preferably, in steps 1-3, the monitoring instrument used to conduct full-process deformation monitoring and record deep soil displacement data in real time during the dewatering of the dock is an intelligent digital inclinometer.

[0010] Preferably, step 2 specifically includes: Step 2-1: Clean and repair the bottom plate of the dock structure; Step 2-2: Repair the tie rods on the dock structure; Steps 2-3: Clean and construct the dock walls of the dock structure; Steps 2-4: Replace the auxiliary facilities of the dock structure.

[0011] Preferably, step 2-1 specifically includes: Truck cranes were used to lift forklifts and sweepers into the dock, clear silt, concrete blocks and timber, and long-arm excavators transported the excavated soil to the designated location; the bottom plate was roughened, the steel bars of the dock were replaced, and concrete was poured.

[0012] Preferably, step 2-2 specifically includes: Clean the rust off the tie rods of the dock structure, record the rust and diameter reduction of the tie rods, perform the welding and anchoring process of angle iron and pad, weld the end plate to increase the anchoring force, and weld the nut to the tie rod; select tie rods for jack test pull to confirm that the tie rod bearing capacity meets the design requirements, and then install the tie rod extension monitoring device.

[0013] Preferably, in step 2-2, the following methods are used: recording the corrosion and diameter reduction of the tie rod; performing the welding and anchoring process of the angle iron and the pad; welding the end plate to increase the anchoring force; and welding the nut to the tie rod. Record the overall corrosion level of the tie rod, the location and depth of local pitting corrosion, the corrosion status of the threads, and the corrosion status of the nuts and steel washers; measure the actual outer diameter of the tie rod base material, compare it with the design outer diameter, and determine the location, length, and amount of diameter reduction; The angle irons are symmetrically arranged and attached to both sides of the extension part of the tie rod. The angle irons and the tie rod are temporarily fixed by tack welding. The fit between the angle irons and the tie rod and the straightness of the tie rod axis are checked. After the adjustment is correct, the full welding is carried out. The custom steel pad is inserted into the end of the tie rod extension and attached to the outside of the angle iron welding surface. The steel pad is then fully welded to the tie rod and angle iron using a perimeter welding method.

[0014] Preferably, steps 2-3 specifically include: The elevator is hoisted into the dock chamber. After the rust on the steel sheet piles is cleaned manually, the loose rust is washed off with a high-pressure water gun. The dock wall lining is poured in three stages and fixed with pre-embedded bolts using shaped steel molds. Water-swellable rubber strips are placed at the construction joints to prevent leakage. The dock wall is constructed in 20m sections. Each dock is equipped with two sets of templates and four groups of construction workers. Construction proceeds from the stern to the dock entrance.

[0015] Preferably, steps 2-4 specifically include: The old mooring bollards of the dock structure were removed, bolts were drilled on site, and new mooring bollards were installed after the base was grouted. Bolts were pre-embedded when the dock wall lining was poured, and new rubber fenders were installed directly using a crane. The trolley rails were repaired by installing bolts and steel pads on the existing foundation of the dock structure and welding them to the rails, or by removing the old rails, cutting off the exposed bolts, installing rebars, installing new rails, and grouting.

[0016] Preferably, step 3 specifically includes: Step 3-1: Dredge the wharf; Step 3-2: Repair the dock structure; Step 3-3: Replace the dock's ancillary facilities.

[0017] Preferably, step 3-1 specifically includes: The process involved sequentially sweeping the sea, constructing trash racks, and dredging. In accordance with the soil pollution standards of the Environmental Protection Law, uncontaminated soil and contaminated soil were treated separately. After dredging, the sea was swept and measured. Once the sea sweeping and measurement were deemed satisfactory, the land was handed over.

[0018] Preferably, step 3-2 specifically includes: Cut cracks in the wharf structure to a depth of 3-5cm, attach grouting nozzles and inject epoxy resin; cut damaged areas of the wharf structure concrete to a depth of 10mm, remove loose concrete to expose 30-50mm of reinforcing bars, reinforce as needed, seal and grout; for the construction of the precast square pile platform on the revetment, first pre-drill holes, use a pile driving frame to drive piles, avoid on-site tracks and drainage facilities, first construct square piles between the two tracks, then construct square piles at the front edge of the wharf, and complete pile foundation testing after pile driving.

[0019] Preferably, in step 3-2, the method of reinforcing and sealing with grout after molding, depending on the situation, is as follows: After cleaning the damaged area, a professional PE engineer will conduct an on-site assessment. If any of the following conditions are met, reinforcement is required; otherwise, proceed directly to the sealing and grouting process: Condition 1: The steel reinforcement of the original wharf structure has a cross-sectional loss of ≥10% due to corrosion, steel reinforcement is broken, or the exposed steel reinforcement length is >300mm; Condition 2: The depth of the damaged area of ​​the wharf structure is ≥150mm and the area is ≥0.5㎡; Condition 3: The damaged area of ​​the wharf structure is located at the critical stress points of the wharf beam ends, column bases, and slab edges, or in high-stress areas subjected to ship impacts and tidal erosion. Condition 4: The spacing between the reinforcing bars in the original wharf structure is too large, meaning that the repaired structure cannot meet the requirements for structural stress and crack resistance.

[0020] Preferably, step 3-3 specifically includes: Remove the old rubber fenders at the dock, cut off the exposed bolts at the dock, drill holes and insert bolts according to the new fender layout at the dock, and then install the new fenders; replace the dock mooring bollards according to the dock mooring bollard replacement process.

[0021] Preferably, step 4 specifically includes: Step 4-1: Construct the shackle piles for the floating dock; Step 4-2: Perform independent platform construction for the floating dock.

[0022] Preferably, step 4-1 specifically includes: After measuring the pile deviation of the shackle piles in the floating dock, auxiliary piles are driven, and a guide frame system is installed. A crane vessel equipped with a vibratory hammer and an impact hammer is used to drive the piles. The auxiliary piles are used to control the pile position and verticality. After the pile driving is completed, the guide frame is removed.

[0023] Preferably, step 4-2 specifically includes: The auxiliary piles of the floating dock were driven and the guide frame was installed. The steel pipe pile limit and clamp installation were completed. The bottom formwork was erected, the steel bars were tied, the side formwork was erected, and the concrete was poured in layers to complete the construction of the independent platform.

[0024] Preferably, step 5 specifically includes: Step 5-1: Repair the retaining wall on the back of the revetment, that is, after on-site investigation, level the site, lay the ballast layer, install the precast concrete blocks in sequence, fill the gaps with ballast, and hand over after acceptance. Step 5-2: Repair the berth, which involves planting and binding steel bars on the top of the corroded steel pipe piles of the berth, wrapping the damaged area, and increasing the load capacity to 4KPa. Step 5-3: Carry out the construction of the pump room and the power room. Before dismantling the pump room pipeline, conduct gas detection. If necessary, clean it with water and then cut it. Transfer the components using a hand-operated hoist. For the power room construction, first pre-drill holes to reduce disturbance to the surrounding structure. Then, carry out the following steps in sequence: remove the surface concrete, pour the foundation layer, construct the base slab and wall columns, erect the full-span scaffolding, pour the top slab, and install the lightning protection device.

[0025] Preferably, step 6 specifically includes: The equipment and materials are transported to the pump room via a crane through the hoisting hole, and short-distance transport is carried out by hydraulic handcarts. The equipment is then hoisted to the installation position using hand-operated hoists on the roof and columns. The installation of water pumps, pipelines and fire protection facilities is completed by a designated subcontractor.

[0026] The beneficial effects of the present invention are as follows, compared with the prior art: A measurement and control network conforming to relevant standards was established, and the number of deep soil displacement monitoring points was optimized to 32, enabling real-time deformation monitoring throughout the dock pumping and construction process. The maximum displacement during pumping was 27.4 mm, which dropped to 24.52 mm and then stabilized. All monitoring data were within the warning range, effectively avoiding safety risks such as structural collapse. The tie rod repair adopted a welding process using angle iron and pads. After testing with 30 tie rod jacks, all met the design tensile force requirements, solving the core problem of tie rod corrosion failure. The anchoring force and bearing capacity of the tie rods were significantly improved. The dock wall was poured in three stages and water-swellable rubber strips were installed to avoid concrete segregation and formwork deformation problems during high-height pouring. There was no water leakage at the construction joints, and the overall pouring quality of the dock wall met the standards. H16 shear steel bars were embedded in the bottom slab repair to achieve reliable bonding between the old and new concrete, solving the defect of poor bonding force at the interface and effectively preventing secondary cracking of the bottom slab. After the reinforcement was wrapped around the top of the pier piles, the load capacity reached 4 kPa, meeting the owner's requirements and providing a foundation for subsequent corrosion protection. The dock wall was constructed using a segmented, continuous construction process, with 20m sections. Two sets of formwork and a specialized construction team were employed. The first section was completed in 28 days, with subsequent sections completed every 6 days. The 38 sections of Dock No. 2 were completed in just 136 days, representing an efficiency improvement of over 60% compared to traditional monolithic construction methods. Each process was planned and coordinated in advance; for example, tie rod welding and rebar roughening were carried out ahead of schedule. The rebar processing area was located inside the dock to reduce transport, further shortening the construction period. The revetment square piles were constructed using pre-drilling and small-scale piling rigs. The inner square piles were constructed first, followed by the front square piles, effectively reducing the horizontal force exerted by the equipment's weight on the front steel sheet piles of the wharf. Pre-drilling was used for the electrical room pile foundation construction to avoid secondary disturbance to the corroded dock wall steel sheet piles, protecting the existing hydraulic structures. Construction surveying followed local standards such as SLA, SS, and ISI throughout the process. All construction techniques underwent engineering evaluation and testing verification, ensuring traceability and inspectability. This met the stringent requirements of Singaporean construction engineering and provided a standardized construction reference for overseas port engineering restoration. By specifically repairing core structures such as dock walls, tie rods, and berthing piers, replacing aging mooring bollards and rubber fenders, and providing cathodic protection recommendations, this invention effectively solves problems such as seawater corrosion and structural aging, significantly extending the service life of the dock structure. It is expected that the repaired structure will meet long-term operational needs. This invention integrates dock repair, wharf construction, floating dock construction, and supporting facility repair into a systematic construction process. The processes are compatible with each other, and construction equipment and personnel can be rationally allocated, reducing construction costs and achieving intensive construction. The construction method of this invention is not only applicable to the Singapore 5JS dock repair project, but can also be adjusted according to the construction specifications of different regions and the structural damage characteristics of old docks. It is widely applicable to the comprehensive repair of old port hydraulic structures in coastal and estuary areas subject to seawater corrosion, and has good engineering application and promotion value. Attached Figure Description

[0027] Figure 1 This is a flowchart of the comprehensive repair and construction method for shipyards and wharves in this invention. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of this invention. The embodiments described in this application are merely some embodiments of this invention, and not all embodiments. Based on the spirit of this invention, other embodiments obtained by those skilled in the art without creative effort are all within the protection scope of this invention.

[0029] like Figure 1 As shown, this invention proposes a comprehensive repair and construction method for docks and wharves, comprising the following steps: This method, through systematic construction surveying and deformation monitoring, phased dock structure repair, wharf dredging and structural reinforcement, floating dock construction, and supporting facility repair, solves a series of technical problems such as wear on the bottom plate of old docks and wharves, corrosion of dock walls, failure of tie rods, and damage to the wharf structure. It achieves efficient and safe repair of old port hydraulic structures, improving the overall load-bearing capacity and service life of the structure. The invention features a clear construction process, close coordination between each phase, deformation monitoring throughout to ensure construction safety, and highly targeted repair techniques, making it suitable for repair projects of similar old coastal docks and wharves. The specific steps are as follows: Step 1: Conduct measurements and deformation monitoring for the comprehensive repair work of the dock and pier; In a preferred but non-limiting embodiment of the present invention, step 1 specifically includes: Step 1-1: Based on local land surveying standards such as SLA and local surveyor specifications such as SS560:2016, SS580:2012 and ISI, a qualified local unit shall set up a primary control network and establish a horizontal and vertical control network. Steps 1-2: Conduct on-site construction layout according to the construction design, set up monitoring points, and complete the installation of 32 deep soil displacement monitoring points before the dock is pumped out. Steps 1-3: Conduct full-process deformation monitoring during the dewatering of the dock, record the displacement data of deep soil in real time, and immediately stop work and rectify when the displacement of the monitoring point exceeds the warning value. After the dewatering is completed, continue monitoring until the displacement tends to stabilize.

[0030] In a preferred but non-limiting embodiment of the present invention, in steps 1-3, the monitoring instrument used to conduct full-process deformation monitoring and record deep soil displacement data in real time during the dewatering of the dock is an intelligent digital inclinometer.

[0031] Step 2: After measurement and deformation monitoring, carry out dock structure repair; In a preferred but non-limiting embodiment of the present invention, step 2 specifically includes: Step 2-1: Clean and repair the bottom plate of the dock structure; In a preferred but non-limiting embodiment of the present invention, step 2-1 specifically includes: Truck cranes were used to lift forklifts and sweepers into the dock to clear silt, concrete blocks, and timber. Long-arm excavators transported the excavated soil to designated locations. The bottom plate was roughened, and the steel bars in the dock were replaced. For example, H13 steel bars were used to replace the original steel bars in dock No. 1 at a 1:1 ratio, and H20 steel bars were used to replace the original steel bars in dock No. 2 at a 1:1 ratio. H16 shear steel bars were inserted at 500mm intervals, and 200mm thick C50 concrete was poured to enhance the bond between the new and old concrete.

[0032] Step 2-2: Repair the tie rods on the dock structure; In a preferred but non-limiting embodiment of the present invention, step 2-2 specifically includes: Clean the rust off the tie rods of the dock structure, record the rust and diameter reduction of the tie rods, implement the welding and anchoring process of angle iron and pad, weld the end plate to increase the anchoring force, and weld the nuts to the tie rods to improve safety; select 30 tie rods (14 in dock No. 1 and 16 in dock No. 2) for jack pull test, and after confirming that the load-bearing capacity of the tie rods meets the design requirements, install the tie rod extension monitoring device.

[0033] In a preferred but non-limiting embodiment of the present invention, in step 2-2, the following methods are included: recording the corrosion and diameter reduction of the tie rod; performing the welding and anchoring process of the angle iron and the pad; welding the end plate to increase the anchoring force; and welding the nut to the tie rod. Record the overall corrosion level of the tie rod, the location and depth of local pitting corrosion, the corrosion condition of the threads, and the corrosion status of the nuts and steel washers. The overall corrosion level of the tie rod is classified according to the steel structure corrosion standards. The corrosion condition of the threads includes whether the exposed threads are completely missing, the degree of thread deformation and damage. The corrosion status of the nuts and steel washers includes whether the nuts and steel washers are rusted shut, cracked, or thinned.

[0034] Methods for detecting the location and depth of localized pitting corrosion, the state of thread corrosion, and the corrosion of nuts and steel washers include: The depth of the base material loss at the deepest point of pitting corrosion on the tie rod is measured using a corrosion depth detector. The actual thickness of the nut and steel washer on the tie rod is measured using a thickness gauge and compared with the design value. The threaded area of ​​the tie rod is inspected in detail to determine whether the threads have lost their connecting function. A high-definition camera is used to take pictures or videos of the rusted parts of the tie rod, the nut, and the washer, and the tie rod number is included in the pictures to ensure that the images correspond to the numbers.

[0035] The key areas to be inspected include the connection between the tie rod and the steel pad, and the exposed section inside the dock wall, which are prone to stress corrosion. The actual outer diameter of the tie rod base material is measured and compared with the design outer diameter to determine the location, length, and amount of diameter reduction. Methods for determining the location, length, and amount of diameter reduction by measuring the actual outer diameter of the tie rod base material and comparing it with the design outer diameter include: For each tie rod, measure the outer diameter at 50cm intervals. For suspected reduced diameter sections, increase the interval to 10cm. Use a digital vernier caliper / outer micrometer to measure the outer diameter in both vertical and horizontal directions on the same cross section, and take the average value as the actual outer diameter of the cross section. Calculate the reduction amount = (designed outer diameter - actual outer diameter) / design outer diameter × 100%, and record the start / end position of the reduced diameter section and the maximum reduction amount.

[0036] Arrange 50×50×8 angle irons symmetrically on both sides of the extension part of the tie rod. Use tack welding to temporarily fix the angle irons and the tie rod. Check the fit between the angle irons and the tie rod and the straightness of the tie rod axis. After adjustment, carry out full welding. The spacing between the tack welding points can be 10cm and the length of the welding point can be 5cm.

[0037] The customized steel pad is inserted into the end of the tie rod extension section and attached to the outside of the angle iron welding surface. The steel pad is then fully welded to the tie rod and angle iron using a perimeter welding method. The weld height is ≥8mm to ensure that the steel pad, tie rod, and angle iron form a whole, distribute the force on the tie rod, and avoid stress concentration in the welded extension section.

[0038] Steps 2-3: Clean and construct the dock walls of the dock structure; In a preferred but non-limiting embodiment of the present invention, steps 2-3 specifically include: The elevator truck was hoisted into the dock chamber. After the rust on the sheet piles was cleaned manually, the loose rust was washed off with a high-pressure water gun. The dock wall lining was poured in three stages. For example, the first pour was 1.75m long. The steel bars were tied directly to the bottom plate of the dock chamber, the formwork was erected, and the reinforcing bars were pre-embedded. The second pour was 5m long, and the third pour was 4.5m long. The standard steel formwork was fixed with pre-embedded bolts, and water-swellable rubber strips were placed at the construction joints to prevent leakage. The dock wall was constructed in 20m sections. Each dock was equipped with two sets of formwork and four groups of construction workers. The construction proceeded from the stern to the dock entrance.

[0039] Steps 2-4: Replace the auxiliary facilities of the dock structure.

[0040] In a preferred but non-limiting embodiment of the present invention, steps 2-4 specifically include: The old mooring bollards of the dock structure were removed, and M36 bolts were drilled and inserted on site. After the base was grouted, new mooring bollards were installed. Bolts were pre-embedded when the dock wall lining was poured, and new rubber fenders were installed directly using a crane. The trolley rails were repaired. Bolts were inserted into the existing foundation of the dock structure, steel pads were installed and welded to the rails, or the old rails were removed, exposed bolts were cut off, and new rails were installed and grouted.

[0041] Step 3: After the dry dock structure repair is completed, the dock construction will commence; In a preferred but non-limiting embodiment of the present invention, step 3 specifically includes: Step 3-1: Dredge the wharf; In a preferred but non-limiting embodiment of the present invention, step 3-1 specifically includes: The process involved sequentially sweeping the sea, constructing trash racks, and dredging. In accordance with the soil pollution standards of the Environmental Protection Law, uncontaminated soil and contaminated soil were treated separately. After dredging, the sea was swept and measured. Once the sea sweeping and measurement were deemed satisfactory, the land was handed over.

[0042] Step 3-2: Repair the dock structure; In a preferred but non-limiting embodiment of the present invention, step 3-2 specifically includes: Cut 3-5cm deep into the cracks in the wharf structure, attach grouting nozzles and inject epoxy resin; cut 10mm deep into the damaged concrete area of ​​the wharf structure, remove loose concrete to expose 30-50mm of reinforcing bars, reinforce as needed, seal and grout; for the construction of the precast square pile platform on the revetment, first pre-drill holes, use a small pile driver to drive piles, avoid on-site facilities such as tracks and ditches, first construct the square piles between the two tracks, then construct the square piles at the front edge of the wharf, and complete the pile foundation testing after pile driving.

[0043] In a preferred but non-limiting embodiment of the present invention, in step 3-2, the method of reinforcing and sealing with grouting as appropriate is as follows: After cleaning the damaged area, a professional PE engineer will conduct an on-site assessment. If any of the following conditions are met, reinforcement is required; otherwise, proceed directly to the sealing and grouting process: Condition 1: The steel reinforcement of the original wharf structure has a cross-sectional loss of ≥10% due to corrosion, steel reinforcement is broken, or the exposed steel reinforcement length is >300mm; Condition 2: The depth of the damaged area of ​​the wharf structure is ≥150mm and the area is ≥0.5㎡, and the effective cross-section of the original wharf structure is severely weakened; Condition 3: The damaged area of ​​the wharf structure is located in key stress-bearing parts such as the ends of the wharf beams, column bases, and slab edges, or in high-stress areas subjected to ship impacts and tidal erosion. Condition 4: The spacing between the reinforcing bars in the original wharf structure is too large, meaning that the repaired structure cannot meet the requirements for structural stress and crack resistance.

[0044] Step 3-3: Replace the dock's ancillary facilities.

[0045] In a preferred but non-limiting embodiment of the present invention, step 3-3 specifically includes: Remove the old rubber fenders at the dock, cut off the exposed bolts at the dock, drill holes and insert bolts according to the new fender layout at the dock, and then install the new fenders; replace the dock mooring bollards according to the dock mooring bollard replacement process.

[0046] Step 4: After the dock construction is completed, the floating dock construction will proceed; In a preferred but non-limiting embodiment of the present invention, step 4 specifically includes: Step 4-1: Construct the shackle piles for the floating dock; In a preferred but non-limiting embodiment of the present invention, step 4-1 specifically includes: After measuring the pile deviation of the shackle piles in the floating dock, auxiliary piles are driven, and a guide frame system is installed. A 280t crane vessel equipped with a 13t vibratory hammer and a 20t impact hammer is used for pile driving. The auxiliary piles are used to control the pile position and verticality. After the pile driving is completed, the guide frame is removed. The single pile weight of the shackle pile can be 49t.

[0047] Step 4-2: Perform independent platform construction for the floating dock.

[0048] In a preferred but non-limiting embodiment of the present invention, step 4-2 specifically includes: The auxiliary piles of the floating dock were driven and the guide frame was installed. The steel pipe pile limit and clamp installation were completed. The bottom formwork was erected, the steel bars were tied, the side formwork was erected, and the concrete was poured in layers to complete the construction of the independent platform.

[0049] Step 5: After the floating dock construction is completed, the supporting facilities will be repaired; In a preferred but non-limiting embodiment of the present invention, step 5 specifically includes: Step 5-1: Repair the retaining wall on the back of the revetment, that is, after on-site investigation, level the site, lay the ballast layer, install C40 / 50 precast concrete blocks in sequence, fill the gaps with ballast, and hand over after acceptance. Step 5-2: Repair the berth, which involves planting and binding reinforcing bars on the top of the corroded steel pipe piles of the M3a berth, wrapping the damaged area, and increasing the load capacity to 4KPa. It is recommended to implement cathodic protection measures. Step 5-3: Carry out the construction of the pump room and the power room. Before dismantling the pump room pipeline, conduct gas detection. If necessary, clean it with water and then cut it. Transfer the components using a hand-operated hoist. For the power room construction, first pre-drill holes to reduce disturbance to the surrounding structure. Then, carry out the following steps in sequence: remove the surface concrete, pour the foundation layer, construct the base slab and wall columns, erect the full-span scaffolding, pour the top slab, and install the lightning protection device.

[0050] Step 6: After repairing the supporting facilities, install the electromechanical and fire protection facilities.

[0051] In a preferred but non-limiting embodiment of the present invention, step 6 specifically includes: The equipment and materials are transported to the pump room via a crane through the hoisting hole, and short-distance transport is carried out by hydraulic handcarts. The equipment is then hoisted to the installation position using hand-operated hoists on the roof and columns. The installation of water pumps, pipelines and fire protection facilities is completed by a designated subcontractor.

[0052] This invention optimizes the number of deep soil displacement monitoring points, increasing them from 10 to 32, enabling precise deformation monitoring throughout the dock pumping and construction process, ensuring construction safety. The dock wall lining employs a three-stage pouring process, controlling the concrete pouring speed and using water-swellable rubber strips to address quality and leakage issues during high-altitude pouring. Tie rod repair utilizes angle iron and pad welding, combined with jack testing, ensuring tie rod anchorage and bearing capacity. H16 shear steel bars are embedded in the dock floor repair, ensuring reliable bonding between new and old concrete and preventing secondary cracking. The dock wall is constructed in sections with two sets of formwork for every 20m section, progressing from the stern to the dock entrance, improving construction efficiency. The revetment square pile construction uses a small pile driver + pre-drilling process, reducing horizontal disturbance to the steel sheet piles at the wharf's edge.

[0053] The beneficial effects of the present invention are as follows, compared with the prior art: A measurement and control network conforming to relevant standards was established, and the number of deep soil displacement monitoring points was optimized to 32, enabling real-time deformation monitoring throughout the dock pumping and construction process. The maximum displacement during pumping was 27.4 mm, which dropped to 24.52 mm and then stabilized. All monitoring data were within the warning range, effectively avoiding safety risks such as structural collapse. The tie rod repair adopted a welding process using angle iron and pads. After testing with 30 tie rod jacks, all met the design tensile force requirements, solving the core problem of tie rod corrosion failure. The anchoring force and bearing capacity of the tie rods were significantly improved. The dock wall was poured in three stages and water-swellable rubber strips were installed to avoid concrete segregation and formwork deformation problems during high-height pouring. There was no water leakage at the construction joints, and the overall pouring quality of the dock wall met the standards. H16 shear steel bars were embedded in the bottom slab repair to achieve reliable bonding between the old and new concrete, solving the defect of poor bonding force at the interface and effectively preventing secondary cracking of the bottom slab. After the reinforcement was wrapped around the top of the pier piles, the load capacity reached 4 kPa, meeting the owner's requirements and providing a foundation for subsequent corrosion protection. The dock wall was constructed using a segmented, continuous construction process, with 20m sections. Two sets of formwork and a specialized construction team were employed. The first section was completed in 28 days, with subsequent sections completed every 6 days. The 38 sections of Dock No. 2 were completed in just 136 days, representing an efficiency improvement of over 60% compared to traditional monolithic construction methods. Each process was planned and coordinated in advance; for example, tie rod welding and rebar roughening were carried out ahead of schedule. The rebar processing area was located inside the dock to reduce transport, further shortening the construction period. The revetment square piles were constructed using pre-drilling and small-scale piling rigs. The inner square piles were constructed first, followed by the front square piles, effectively reducing the horizontal force exerted by the equipment's weight on the front steel sheet piles of the wharf. Pre-drilling was used for the electrical room pile foundation construction to avoid secondary disturbance to the corroded dock wall steel sheet piles, protecting the existing hydraulic structures. Construction surveying followed local standards such as SLA, SS, and ISI throughout the process. All construction techniques underwent engineering evaluation and testing verification, ensuring traceability and inspectability. This met the stringent requirements of Singaporean construction engineering and provided a standardized construction reference for overseas port engineering restoration. By specifically repairing core structures such as dock walls, tie rods, and berthing piers, replacing aging mooring bollards and rubber fenders, and providing cathodic protection recommendations, this invention effectively solves problems such as seawater corrosion and structural aging, significantly extending the service life of the dock structure. It is expected that the repaired structure will meet long-term operational needs. This invention integrates dock repair, wharf construction, floating dock construction, and supporting facility repair into a systematic construction process. The processes are compatible with each other, and construction equipment and personnel can be rationally allocated, reducing construction costs and achieving intensive construction. The construction method of this invention is not only applicable to the Singapore 5JS dock repair project, but can also be adjusted according to the construction specifications of different regions and the structural damage characteristics of old docks. It is widely applicable to the comprehensive repair of old port hydraulic structures in coastal and estuary areas subject to seawater corrosion, and has good engineering application and promotion value.

[0054] 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 without departing from the spirit and scope of the present invention. Any modifications or equivalent substitutions should be covered within the scope of protection of the claims of the present invention.

Claims

1. A method for comprehensive repair and construction of docks and wharves, characterized in that, include: Step 1: Conduct measurements and deformation monitoring for the comprehensive repair work of the dock and pier; Step 2: After measurement and deformation monitoring, carry out dock structure repair; Step 3: After the dry dock structure repair is completed, the dock construction will commence; Step 4: After the dock construction is completed, the floating dock construction will proceed; Step 5: After the floating dock construction is completed, the supporting facilities will be repaired; Step 6: After repairing the supporting facilities, install the electromechanical and fire protection facilities.

2. The method for comprehensive repair and construction of shipyards and wharves according to claim 1, characterized in that, Step 1 specifically includes: Step 1-1: Based on local land surveying standards and local surveyor specifications, a qualified local unit shall set up a primary control network and establish a horizontal and vertical control network. Steps 1-2: Conduct on-site construction layout according to the construction design, set up monitoring points, and complete the installation of deep soil displacement monitoring points before the dock is pumped out. Steps 1-3: Conduct full-process deformation monitoring during the dewatering of the dock, record the displacement data of deep soil in real time, and suspend work for rectification when the displacement of the monitoring point exceeds the warning value. After the dewatering is completed, continue monitoring until the displacement tends to stabilize. In steps 1-3, deformation monitoring is carried out throughout the entire process of dewatering in the dock. The monitoring instrument used to record the displacement data of deep soil in real time is an intelligent digital inclinometer.

3. The method for comprehensive repair and construction of docks and wharves according to claim 2, characterized in that, Step 2 specifically includes: Step 2-1: Clean and repair the bottom plate of the dock structure; Step 2-2: Repair the tie rods on the dock structure; Steps 2-3: Clean and construct the dock walls of the dock structure; Steps 2-4: Replace the auxiliary facilities of the dock structure.

4. The method for comprehensive repair and construction of docks and wharves according to claim 3, characterized in that, Step 2-1 specifically includes: Truck cranes were used to lift forklifts and sweepers into the dock, clear silt, concrete blocks and timber, and long-arm excavators transported the excavated soil to the designated location; the bottom plate was roughened, the steel bars of the dock were replaced, and concrete was poured. Step 2-2 specifically includes: Clean the rust on the tie rods of the dock structure, record the rust and diameter reduction of the tie rods, implement the welding and anchoring process of angle iron and pad, weld the end plate to increase the anchoring force, and weld the nut to the tie rod; select tie rods for jack test pull to confirm that the tie rod bearing capacity meets the design requirements, and then install the tie rod extension monitoring device; In step 2-2, the corrosion and diameter reduction of the tie rod are recorded, and the angle iron and pad are welded together to extend the anchorage. The end plate is welded to increase the anchorage force. The method of welding the nut to the tie rod includes: Record the overall corrosion level of the tie rod, the location and depth of local pitting corrosion, the corrosion status of the threads, and the corrosion status of the nuts and steel washers; measure the actual outer diameter of the tie rod base material, compare it with the design outer diameter, and determine the location, length, and amount of diameter reduction; The angle irons are symmetrically arranged and attached to both sides of the extension part of the tie rod. The angle irons and the tie rod are temporarily fixed by tack welding. The fit between the angle irons and the tie rod and the straightness of the tie rod axis are checked. After the adjustment is correct, the full welding is carried out. The custom steel pad is inserted into the end of the tie rod extension and attached to the outside of the angle iron welding surface. The steel pad is then fully welded to the tie rod and angle iron using a perimeter welding method.

5. The method for comprehensive repair and construction of shipyards and wharves according to claim 4, characterized in that, Steps 2-3 specifically include: The elevator is hoisted into the dock chamber. After the rust on the steel sheet piles is manually cleaned, the loose rust is washed off with a high-pressure water gun. The dock wall lining is poured in three stages and fixed with pre-embedded bolts using shaped steel molds. Water-swellable rubber strips are placed at the construction joints to prevent leakage. The dock wall is constructed in 20m sections. Each dock is equipped with two sets of templates and four groups of construction workers. Construction proceeds from the stern to the dock entrance. Steps 2-4 specifically include: The old mooring bollards of the dock structure were removed, bolts were drilled on site, and new mooring bollards were installed after the base was grouted. Bolts were pre-embedded when the dock wall lining was poured, and new rubber fenders were installed directly using a crane. The trolley rails were repaired by installing bolts and steel pads on the existing foundation of the dock structure and welding them to the rails, or by removing the old rails, cutting off the exposed bolts, installing rebars, installing new rails, and grouting.

6. The method for comprehensive repair and construction of shipyards and wharves according to claim 5, characterized in that, Step 3 specifically includes: Step 3-1: Dredge the wharf; Step 3-2: Repair the dock structure; Step 3-3: Replace the dock's ancillary facilities.

7. The method for comprehensive repair and construction of shipyards and wharves according to claim 6, characterized in that, Step 3-1 specifically includes: The process of sweeping the sea, constructing trash racks, and dredging was carried out in sequence. Uncontaminated soil and contaminated soil were treated separately in accordance with the soil pollution standards of the Environmental Protection Law. After dredging, the sea was swept and measured. After the sea sweep and measurement were qualified, the land was handed over. Step 3-2 specifically includes: Cut 3-5cm deep into the cracks in the wharf structure, attach grouting nozzles and inject epoxy resin; cut 10mm deep into the damaged concrete area of ​​the wharf structure, remove loose concrete to expose 30-50mm of rebar, reinforce as needed, seal and grout; for the construction of the precast square pile platform on the revetment, first pre-drill holes, use a pile driving frame to drive piles, avoid the on-site tracks and water ditch facilities, first construct the square piles between the two tracks, then construct the square piles at the front edge of the wharf, and complete the pile foundation testing after pile driving; In step 3-2, the method of reinforcing and sealing with grouting as needed is as follows: After cleaning the damaged area, a professional PE engineer will conduct an on-site assessment. If any of the following conditions are met, reinforcement is required; otherwise, proceed directly to the sealing and grouting process: Condition 1: The steel reinforcement of the original wharf structure has a cross-sectional loss of ≥10% due to corrosion, steel reinforcement is broken, or the exposed steel reinforcement length is >300mm; Condition 2: The depth of the damaged area of ​​the wharf structure is ≥150mm and the area is ≥0.5㎡; Condition 3: The damaged area of ​​the wharf structure is located at the critical stress points of the wharf beam ends, column bases, and slab edges, or in high-stress areas subjected to ship impacts and tidal erosion. Condition 4: The spacing between the reinforcing bars in the original wharf structure is too large, meaning that the repaired structure cannot meet the requirements for structural stress and crack resistance. Step 3-3 specifically includes: Remove the old rubber fenders at the dock, cut off the exposed bolts at the dock, drill holes and insert bolts according to the new fender layout at the dock, and then install the new fenders; replace the dock mooring bollards according to the dock mooring bollard replacement process.

8. The method for comprehensive repair and construction of shipyards and wharves according to claim 7, characterized in that, Step 4 specifically includes: Step 4-1: Construct the shackle piles for the floating dock; Step 4-2: Construct the independent platform for the floating dock; Step 4-1 specifically includes: After measuring the pile deviation of the shackle piles in the floating dock, auxiliary piles are driven, and a guide frame system is installed. A crane ship equipped with a vibratory hammer and an impact hammer is used to drive the piles. The auxiliary piles are used to control the pile position and verticality. After the pile driving is completed, the guide frame is removed. Step 4-2 specifically includes: The auxiliary piles of the floating dock were driven and the guide frame was installed. The steel pipe pile limit and clamp installation were completed. The bottom formwork was erected, the steel bars were tied, the side formwork was erected, and the concrete was poured in layers to complete the construction of the independent platform.

9. The method for comprehensive repair and construction of docks and wharves according to claim 8, characterized in that, Step 5 specifically includes: Step 5-1: Repair the retaining wall on the back of the revetment, that is, after on-site investigation, level the site, lay the ballast layer, install the precast concrete blocks in sequence, fill the gaps with ballast, and hand over after acceptance. Step 5-2: Repair the berth, which involves planting and binding steel bars on the top of the corroded steel pipe piles of the berth, wrapping the damaged area, and increasing the load capacity to 4KPa. Step 5-3: Carry out the construction of the pump room and the power room. Before dismantling the pump room pipeline, conduct gas detection. If necessary, clean it with water and then cut it. Transfer the components using a hand-operated hoist. For the power room construction, first pre-drill holes to reduce disturbance to the surrounding structure. Then, carry out the following steps in sequence: remove the surface concrete, pour the foundation layer, construct the base slab and wall columns, erect the full-span scaffolding, pour the top slab, and install the lightning protection device.

10. The method for comprehensive repair and construction of shipyards and wharves according to claim 9, characterized in that, Step 6 specifically includes: The equipment and materials are transported to the pump room via a crane through the hoisting hole, and short-distance transport is carried out by hydraulic handcarts. The equipment is then hoisted to the installation position using hand-operated hoists on the roof and columns. The installation of water pumps, pipelines and fire protection facilities is completed by a designated subcontractor.

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