Construction method for overflowing surface lining mirror surface concrete of complex high-flow-rate flood discharge tunnel

Abstract

The invention discloses a complex-body-type high-flow-speed flood discharge tunnel overflowing face lining mirror surface concrete construction method, and relates to the technical field of concrete construction technologies, and the method comprises the steps of manufacturability testing, shape automatic deformation formwork machining, measuring and point placing, steel bar manufacturing and installing, embedded part construction, concrete warehousing and pouring. 5 times of process tests and 4 times of simulation are carried out on site, a composite steel formwork formed by compounding a steel plate with the thickness of 10 mm and a stainless steel plate with the thickness of 2 mm is adopted for pouring concrete on the side wall of the flood discharging tunnel, and the concrete construction parameters are as follows: the mark number is C9040W8F150, the slump is 70-90 mm, loose laying is 0.45 m, initial vibration is 60 s, compound vibration is 45 s, and the interval is 20 min. Through a mirror concrete manufacturability test, accurate, flat, smooth and defect-free construction of the concrete body is realized, and the problem that the surface of the concrete is abraded and damaged by extremely fast water flow in a high-flow-rate flood discharge tunnel is solved; and a complete set of mirror surface concrete construction methods such as high side wall compound vibration, bottom plate five-step fine surface finishing, curved surface bottom plate circulating rollover and seamless connection of construction joints are created.

Description

Technical Field

[0001] The invention relates to the technical field of concrete construction technology, in particular to a mirror concrete construction method for lining the flow surface of a complex-shaped high-flow-rate flood discharge tunnel. Background Art

[0002] With the development of water conservancy and hydropower projects, the design and construction of spillway tunnels face higher requirements. Different from tunnels in the fields of transportation and mining, hydraulic tunnels generally require flow. If the tunnel lining surface is uneven and there are defects such as construction joints, structural joints, and honeycomb surfaces, the roughness and head loss of the tunnel will be increased, which will have an important impact on the function of long-distance water transportation (diversion) projects. At the same time, cavitation and abrasion damage are prone to occur during long-term operation, especially for high-velocity spillway tunnel projects. Similar damage cases are common at home and abroad. Especially for spillway tunnels with complex shapes and high flow rates, the quality of the lining of the flow surface directly affects the safety and service life of the structure. Traditional construction methods are difficult to meet the high quality requirements of mirror concrete.

[0003] Existing technology: Carefully design the concrete mix ratio, select high-quality cement, well-graded aggregates and high-performance admixtures; customize high-precision formwork, generally use steel formwork or high-quality wooden formwork to ensure that the formwork fits tightly with the complex-shaped spillway flow surface to ensure the shape and size accuracy of the concrete lining; during the concrete pouring process, adopt the method of layered pouring and reasonable vibration, and at the same time, take special protective measures for high-velocity areas, such as setting up temporary water retaining facilities or adjusting the pouring sequence; after the concrete is poured, carry out fine surface treatment, including grinding, polishing and other processes;

[0004] Constructing hydraulic water supply (diversion) and flood discharge tunnels with precise shape, bright appearance and solid interior, wear resistance and crack resistance is an important guarantee for the safe operation of the project, and it is also a global problem. In view of the problems of shape, unevenness, cracks and other issues of the complex "mirror" concrete forming surface, combined with the special pouring service environment and hydrogeological conditions of the mirror concrete lining of the complex flood discharge tunnel flow surface, the difficulties of crack control, pouring quality and efficiency optimization are focused on;

[0005] High-quality mirror concrete lining can effectively resist the scouring of high-velocity water flow, reduce the risk of cracks and leakage, and ensure the structural safety of the spillway tunnel. The surface of the mirror concrete is smooth and flat, with a good appearance effect, reflecting the high quality and high level of engineering construction. Through the research and practice of mirror concrete construction technology for lining the flow surface of complex high-velocity spillway tunnels, it can provide valuable experience and reference for the construction of similar projects in the future, promote the innovation and development of concrete construction technology, and improve the overall level of water conservancy project construction in my country.

[0006] Therefore, it is very necessary to propose a mirror concrete construction method for lining the flow surface of a complex high-flow rate spillway tunnel in this application to solve the problems in the background.

[0007] 1. Patent document CN110409388B discloses a method for constructing large cavern floor concrete with high velocity and low slump. The above patent effectively solves the problem that the vertical height of the space changes gradually due to the inconsistent slope of the top arch and the bottom lining of the large cavern, and the trolley lining cannot be used. This construction method effectively ensures the construction quality of the large-section special-shaped structural side walls and top arch concrete, and improves the impact and wear resistance of the concrete flow surface. However, the above patent cannot achieve the construction of precise, smooth and defect-free concrete body.

[0008] 2. Patent document CN110130282B discloses a method for temperature control and crack prevention during the construction period of spillway tunnel lining concrete. The above patent realizes a method for temperature control and crack prevention during the construction period of spillway tunnel lining concrete to meet the temperature control and crack prevention requirements, which can effectively prevent the generation of cracks in the spillway tunnel lining concrete, and has a significant anti-cracking effect. It has important reference value for the construction of spillway tunnel projects, but the above patent cannot achieve low-heat, high-strength, high-crack and impact-resistant high-performance concrete.

[0009] 3. Patent document CN113847063B discloses a method for simulating the construction of secondary lining concrete for tunnels. The above patent evaluates the construction performance of lining concrete during the pouring construction process through three indicators: pouring and vibration time, lining template pressure change, and surface morphology of lining concrete after hardening. The evaluation indicators are comprehensive and mutually verified, and the evaluation results are accurate and reliable. The present invention has important theoretical significance and practical value for the evaluation of the construction performance of secondary lining concrete for tunnels and the quality control of pouring construction, but the above patent cannot achieve temperature control of large-section lining concrete.

[0010] 4. Patent document CN111535268B discloses a construction method for the lining layer of a large-section water diversion tunnel in Class IV and V surrounding rock areas. The above patent realizes a construction method for the lining layer of a large-section water diversion tunnel in Class IV and V surrounding rock areas, which can make the prestress evenly diffuse and facilitate the control of the deformation of the diversion tunnel. It includes a concrete lining layer, which is lined on the inner wall of the extra-large cross-section water diversion tunnel through an anchoring force diffusion system, and the anchoring force diffusion system is anchored on the IV and V class surrounding rocks of the wall of the extra-large cross-section water diversion tunnel through a large-tonnage prestressed anchoring system. During construction, the construction foundation is first fixed in the excavated cavern, and then the large-tonnage prestressed anchoring system and the anchoring force diffusion system are arranged. Finally, based on the large-tonnage prestressed anchoring system and the anchoring force diffusion system, the concrete lining layer is constructed to complete the construction of the lining layer of the extra-large cross-section water diversion tunnel in the IV and V class surrounding rock areas. However, the above patent cannot realize the easy transportation of normal concrete in a large slope environment.

[0011] In summary, the above patents cannot achieve the precise, smooth and defect-free construction of concrete, low-heat, high-strength, high-crack and abrasion-resistant high-performance concrete, temperature control of large-section lining concrete, and easy transportation of normal concrete in a large slope environment, resulting in the extremely fast water flow in the high-flow spillway tunnel causing wear and damage to the concrete surface, and the large-section low-heat, high-performance concrete thin-wall lining structure is easily affected by temperature and cracked, which cannot ensure the quality of materials and personnel safety;

[0012] To this end, the present application proposes a mirror concrete construction method for the lining of the flow surface of a complex-shaped, high-flow-rate spillway tunnel that can achieve precise, smooth and defect-free construction of concrete body, low-heat, high-strength, high-crack and abrasion-resistant high-performance concrete, temperature control of large-section lining concrete, and easy transportation of normal concrete in a large slope environment. Summary of the invention

[0013] The purpose of the present invention is to provide a mirror concrete construction method for the lining of the flow surface of a complex-shaped high-flow rate spillway tunnel, so as to solve the technical problems proposed in the above-mentioned background technology that the concrete shape cannot be accurately, smoothly and defect-freely constructed, low-heat, high-strength, high-crack and abrasion-resistant high-performance concrete, temperature control of large-section lining concrete and easy transportation of normal concrete under a large slope environment, resulting in extremely fast water flow in the high-flow rate spillway tunnel causing wear and damage to the concrete surface, and large-section low-heat, high-performance concrete thin-wall lining structure being easily affected by temperature and cracking, and the inability to ensure material quality and personnel safety.

[0014] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: a method for constructing mirror concrete lining of a flow surface of a complex-shaped high-flow-rate spillway tunnel, including processability test, shape automatic deformation template processing, point measurement, steel bar production and installation, embedded parts construction, concrete warehousing and pouring;

[0015] Five process tests and four simulations were conducted on site. The concrete pouring of the side wall of the spillway tunnel used a composite steel formwork composed of a 10mm thick steel plate and a 2mm thick stainless steel plate. The concrete construction parameters were: C9040W8F150 grade, slump 70-90mm, loose paving 0.45m, initial vibration 60s, re-vibration 45s, interval 20min, vibration point square / plum blossom arrangement, 0.3m spacing; microcapsules containing repair agents, bacteria and enzymes were added to the concrete. Microcapsules containing epoxy resin / polyurethane were used. The microcapsules automatically repaired cracks with a width of less than 0.2mm. Bacteria and enzymes decomposed the surrounding substances to produce calcium carbonate to fill the cracks. Temperature sensors, strain sensors and pressure sensors were buried in the lining structure.

[0016] The template uses a CNC cutting machine to cut the steel plate, and the steel plate and the stainless steel plate are automatically welded by a robot welding system. After welding, the template surface is precisely polished using a CNC grinder.

[0017] Preferably, the shape-automatic deformation template processing adopts automatic deformation of a preset shape, the trolley head template adopts a bulk modified combination template, a memory alloy structure is arranged inside the template, the shape-automatic deformation template is woven by polyurethane and Ni-Ti alloy wire / sheet, the polyurethane material is added with a chain extender to form a thin sheet combined with a rigid frame, the Ni-Ti shape memory alloy is melted and forged to form Ni-Ti alloy wire / sheet, the side mold distance structure is 15cm, the bottom plate and top arch templates adopt wooden molds, and an observation window is reserved for the top arch. After installation, the prestressed pull rod is tightened, and the verticality is adjusted to an error of less than 1cm. The support sequence is first the two ends and then the middle. The water stop and template seams are sealed with foam glue, and epoxy resin / polyurethane microcapsules are used at corners, joints and gaps.

[0018] Preferably, the complex-shaped high-flow-rate spillway tunnel is subjected to field measurement and investigation of the shape, size, flood flow and water level, seismic peak acceleration and response spectrum characteristic period of the spillway tunnel, and three-dimensional scanning is performed using laser scanning technology. A measurement reference point is established at the spillway tunnel engineering site, and the laser scanning equipment is placed at the measurement reference point. Each scanning station is relatively positioned by a positioning target ball / total station; the long and curved spillway tunnel is scanned in sections, and there is a certain overlap between each scanning area; during the scanning process, the three-dimensional coordinates and reflection intensity of each scanning point are synchronously recorded, and the data is wirelessly transmitted to the data storage device and the modeling software, and the scanning progress and some preliminary processed results are displayed in real time on the display screen of the scanning device;

[0019] The 3D modeling software uses laser scanning technology to obtain data to create a 3D model of the spillway tunnel. The 3D model includes the complex shape of the flow surface, lining structure, and steel bar arrangement. In the 3D model, the strength of the concrete, elastic modulus, Poisson's ratio, and the strength and diameter of the steel bar are given to different materials and structures; the 3D model is placed in the simulation software to set the parameters of the construction process; the concrete pouring process is simulated, the flow of concrete in the complex-shaped flow surface is observed, and the accumulation, voids, and cold joints of concrete are predicted. By adjusting the pouring speed and method, the flow properties of concrete are optimized to ensure that the concrete is evenly poured over the entire flow surface; based on the simulation results, possible problems (cracks, leakage, deformation) that may arise during the construction process are predicted, the causes of the problems (concrete shrinkage, temperature stress, water flow impact) are analyzed, and the simulation is repeated.

[0020] Preferably, the measurement points are measured along the axis using a total station, and monitoring points are set up inside and outside the tunnel to calibrate and verify the position of the template. The entire line is divided into 12 warehouses, each warehouse is 12.1m long, and each warehouse is equipped with at least 3 groups of cross-section measurement points. An automated control pad heightening system is used in the lining construction of the broken line. The protective layer uses concrete pads with a strength not less than that of the structure. The pads are fastened to the steel bars by buckles and are dispersedly arranged. The bottom plate adopts a trackless slipform casting process, and the slipform machine is equipped with an automatic leveling and deviation correction system. The concrete lining of the pressure-free tunnel body is cast in the order of "side wall first, then top arch, and then bottom plate". The side walls and top arch are cast using self-propelled hydraulic trolleys, and the trolleys are equipped with laser positioning systems.

[0021] The lining structure uses 3D design software to design the 3D printing model of the lining concrete, determine the printing material, speed and layer thickness of 70-90mm, plan the printing path and sequence, divide the lining concrete of the spillway flow surface into several modules, and assemble them using precast concrete slabs / precast concrete segments. The precast modules are mechanically connected to replicate the special texture / shape of the precast concrete slabs.

[0022] Preferably, the steel bar production adopts fully automatic CNC steel bar processing equipment, and the steel bar cutting, bending and forming are completed in one. The steel bar connection method is as follows:

[0023] For steel bars with a diameter of less than 25 mm, a flash butt welding machine is used for butt welding. The welding parameters are set by an intelligent control system to ensure welding quality.

[0024] For steel bars with a diameter greater than 25 mm, a straight thread connection method is used. A CNC thread rolling machine is used to roll straight threads on the ends of the steel bars. The connecting sleeve is made of alloy steel, with threads on the inner wall, which is tightly connected to the threads on the ends of the steel bars.

[0025] Use a torque wrench to control the tightening torque of the connecting sleeve;

[0026] When installing the steel bars, the side wall steel bars are first measured and laid out to ensure accurate positioning. The vertical steel bars are erected at one time and fixed with steel bar positioning frames and clamps. The main bars of the inner walls and top arches are in the same direction as the side walls. An arc-shaped template is used to ensure the bending radius and positioning of the steel bars. The bottom plate steel bars are laid out according to the center line, side lines and elevation control points. A welded grid sample frame is set up and a movable steel bar binding platform is used. The platform is equipped with a hydraulic lifting system and mobile tracks. The top arch steel bars are installed on anchor rods, which are constructed using an automated drilling machine. The steel bars are bent by pulling wires to form a sample frame. At the same time, the anchor rod reinforcement is increased to stabilize the structure. The seam steel bars pass through the holes reserved in the head template. The gaps are filled with calcium carbonate and the joints are staggered.

[0027] Preferably, the embedded parts are constructed using an adjustable special-shaped purlin fixing template, the adjustable special-shaped purlin fixing template fixes the rubber waterstop and the copper waterstop, the joints of the rubber waterstop are connected by a hot melt welding machine, the lap length is ≥10cm, and the welding process is controlled by a temperature control system; the specifications of the copper waterstop are 460mm / 600mm in width and 1.2mm in thickness, the copper waterstop is welded using an argon arc welding machine, and the weld lap length is ≥2cm.

[0028] Preferably, the side wall concrete is put into the warehouse using a large-slope heavy-load automatic material transport system; the large-slope heavy-load automatic material transport system includes a loading component, a power and drive component, an automatic control component, and a hopper and unloading component; the belt conveyor is connected to the power and drive component through a sprocket, the automatic control component controls the power and drive component through a PLC, and the power and drive component is connected to the hopper and unloading component through a mechanical arm; a weighing sensor and a speed sensor are fixedly installed inside the belt conveyor, the loading component adopts a 10kV / 1400kW variable frequency drive belt conveyor, the belt width is 1.2m, and the belt is made of aramid fiber / carbon fiber; the power component is equipped with a shock-absorbing roller, a shock-absorbing spring / rubber shock absorber is fixedly installed inside the shock-absorbing roller, and limit elements are installed at both ends of the shock-absorbing roller;

[0029] The concrete is transported to the site by a mixer truck from the mixing station. On site, an automated control system backhoe loader is used to shovel the concrete into the belt conveyor of the feeding system. An anti-overflow baffle is installed at the joint between the backhoe loader bucket and the belt conveyor. The belt width of the feeding system is 1.2m. The belt conveyor is equipped with a weighing sensor and a speed sensor. The concrete is transported to the transfer system on the top of the steel mold trolley through the belt conveyor. The transfer system consists of a rotatable distributor. The top transfer system delivers the concrete into the bin. The entire process is coordinated by the PLC automatic control system. The vertical height of the concrete falling in the bin should be controlled within 1.5m. When this height is exceeded, a chute / slow-down chute should be added.

[0030] Preferably, the pouring of the top arch concrete starts from a position 2m below the arch line and pours upward to the arch top. The concrete is pumped into the warehouse using an HTB90 concrete pump. The concrete pump is equipped with an intelligent pumping control system. The pouring sequence is carried out in sequence. The hard overlap method is strictly adopted, and the overlap length is controlled at 3 to 5 cm. During the overlap process, the vertical seams are inspected, polished, hemp-treated, cleaned, and affixed with transparent tape and double-sided tape;

[0031] The side wall is cast in a flat and symmetrical manner. First, a 20cm thick secondary mortar-rich concrete is laid, and a 100mm diameter high-frequency vibrator is used for compaction. The vibrator is equipped with an intelligent monitoring system. The thickness of each embryonic layer is 0.5m, and it is vibrated through the working window. The top arch concrete is fed through a 150mm diameter pumping window. The window position is pre-set on the template and the periphery is sealed with a sealing ring. The pouring is required to be continuous and fast, with a paving thickness of 30-40cm, and the material is laid symmetrically. When the sealing hole is slurry, the pouring is stopped in time;

[0032] The A100 vibrator is used for the first vibration with a vibration time of 60 seconds; the A70 vibrator is used for the re-vibration with a vibration time of 45 seconds, and the vibration is carried out at intervals of 20 minutes. The spacing between vibration points shall not exceed 1.5 times the effective vibration radius. The roughening of the cushion layer and side walls shall be carried out after the grouting of anchor bars. The roughening time is 8 to 12 hours after closing. A high-pressure water gun with a water pressure of 25MPa to 30MPa is used. The roughening depth reaches 2-3mm. The top of the side wall and the top arch are not roughened, and a riding edge protection of less than 30mm is used.

[0033] Preferably, the concrete pouring is additionally vacuum treated, and the vacuum treatment is mainly performed by installing a vacuum pipe on the composite formwork, and small exhaust holes are opened on the composite formwork. The vacuum pump and the composite formwork are connected by vacuum pipes and connecting pipes. An impeller and a working fluid are arranged inside the vacuum pump. The impeller rotates in the pump chamber, and the working fluid forms a rotating liquid ring. The liquid ring and the impeller blades form a periodically changing volume, and the vacuum pump generates negative pressure. The vacuum tank stores the extracted air and part of the water vapor, and the vacuum degree is controlled between -0.06 and -0.08 MPa.

[0034] Preferably, the temperature control system adopts phase change material temperature control technology. During the concrete mixing process, 5%-15% of microencapsulated paraffin phase change materials, admixtures and first-grade fly ash are added to low-heat silicate cement to reduce the unit cement dosage and ultimately control the concrete hydration heat. Avoid pouring during high temperature periods, use awnings and insulation devices, and spray / arrange air conditioners to reduce the ambient temperature of the pouring work surface to reduce the concrete pouring temperature. Apply a layer of thermal insulation coating on the concrete surface. The thermal insulation coating uses a ceramic-based thermal insulation coating. There are a large number of tiny pores inside the thermal insulation coating to prevent heat conduction. The initial cooling of the concrete is carried out by pre-buried cooling water pipes and cooling water cooling. The side wall section of the flood discharge tunnel adopts a "four-in-four-out" form to arrange cooling water pipes, and the top arch section adopts a "two-in-two-out" form to arrange cooling water pipes. The water flow rate in the low temperature season is 2.5m 3 / h, the water flow rate in high temperature season is 4.0m 3 / h;

[0035] Multiple sedimentation tanks are built at the construction site. Wastewater first flows into the primary sedimentation tank, where larger suspended solids are removed through natural sedimentation. The primary sedimentation time is no less than 2 hours. After the primary sedimentation, the wastewater flows into the secondary sedimentation tank. Sand filter / activated carbon is added to the secondary sedimentation tank to remove fine suspended solids. The secondary sedimentation tank adopts an inclined plate sedimentation tank. The sedimentation tank is equipped with an automatic pH adjustment system. The pH sensor monitors the pH value of the wastewater and transmits the signal to the controller. The controller controls the dosing device to add a neutralizer to the wastewater according to the set pH value range (6-8).

[0036] Compared with the prior art, the present invention has the following beneficial effects:

[0037] 1. The present invention has achieved precise, smooth and defect-free construction of concrete through the process test of mirror concrete, solved the problem of wear and damage of concrete surface by extremely fast water flow in high-velocity flood discharge tunnel, and created a set of mirror concrete construction methods such as high side wall re-vibration, five-step fine finishing of bottom plate, circular mold turning of curved bottom plate, and seamless connection of construction joints;

[0038] 2. The present invention uses low-heat silicate cement to achieve low-heat, high-strength, high-crack and abrasion-resistant high-performance concrete, solves the problem between grade lining concrete and crack resistance of the spillway tunnel, and improves the quality and safety of concrete;

[0039] 3. The present invention realizes temperature control of large-section lining concrete through intelligent temperature control technology, solves the problem that large-section low-heat high-performance concrete thin-wall lining structure is easily affected by temperature and cracks, optimizes the concrete mix ratio and construction process, ensures that the concrete lining maintains integrity and stability when subjected to high-speed water flow scouring, thereby enhancing the safety of the entire engineering structure;

[0040] 4. The present invention realizes easy transportation of normal concrete in a steep slope environment through a steep slope heavy-load automated material transport system, solves the problem of difficult transportation of normal concrete in a steep slope environment, and improves transportation efficiency and quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 It is a schematic diagram of the concrete cross section of the side wall of the non-pressure section of the spillway tunnel of the present invention;

[0042] Figure 2 It is a schematic diagram of the connecting sleeve structure of the present invention;

[0043] Figure 3 This is a schematic diagram of the side wall concrete entering the warehouse of the present invention;

[0044] Figure 4 It is a schematic diagram of the top arch concrete entering the warehouse of the present invention;

[0045] Figure 5It is a schematic diagram of the construction method of the present invention. DETAILED DESCRIPTION

[0046] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0047] See also Figure 1 , Figure 2 and Figure 4 , an embodiment provided by the present invention: a method for constructing mirror concrete for the lining of the flow surface of a complex-shaped high-flow-rate flood discharge tunnel, including processability test, shape automatic deformation template processing, point measurement, steel bar production and installation, embedded parts construction, concrete warehousing and pouring;

[0048] Five process tests and four simulations were conducted on site. The concrete pouring of the side wall of the spillway tunnel used a composite steel formwork composed of a 10mm thick steel plate and a 2mm thick stainless steel plate. The concrete construction parameters were: C9040W8F150 grade, slump 70-90mm, loose paving 0.45m, initial vibration 60s, re-vibration 45s, interval 20min, vibration point square / plum blossom arrangement, 0.3m spacing; microcapsules containing repair agents, bacteria and enzymes were added to the concrete. Microcapsules containing epoxy resin / polyurethane were used. The microcapsules automatically repaired cracks with a width of less than 0.2mm. Bacteria and enzymes decomposed the surrounding substances to produce calcium carbonate to fill the cracks. Temperature sensors, strain sensors and pressure sensors were buried in the lining structure.

[0049] The template uses a CNC cutting machine to cut the steel plate, and the steel plate and the stainless steel plate are fully automatically welded by a robot welding system. After welding, the template surface is precisely polished using a CNC grinder; the shape automatic deformation template processing uses a preset shape automatic deformation, the trolley head template uses a bulk modified combined template, a memory alloy structure is set inside the template, the shape automatic deformation template is woven by polyurethane and Ni-Ti alloy wire / sheet, the polyurethane material is added with a chain extender to form a thin sheet combined with a rigid frame, the Ni-Ti shape memory alloy is melted and forged to form Ni-Ti alloy wire / sheet, the side mold distance structure is 15cm, the bottom plate and top arch templates use wooden molds, and the top arch has an observation window reserved. After installation, the prestressed pull rod is tightened, and the verticality is adjusted to an error of less than 1cm. The support sequence is first the two ends and then the middle. The water stop and template seam are sealed with foam glue, and the corners, joints and gaps are made of epoxy resin / polyurethane microcapsules;

[0050] Furthermore, the composite steel formwork uses a CNC cutting machine to cut the steel plate to ensure the accuracy of the formwork size, and the steel plate and the stainless steel plate are fully automatically welded through a robot welding system to ensure uniform weld quality and avoid uneven welds and deformation that may be caused by manual welding. After welding, the formwork surface is precisely polished using a CNC grinder to ensure that the flatness and smoothness of the formwork surface meet mirror requirements. Nano-silicon powder and high-efficiency water reducer are added to the concrete mix to improve the strength and fluidity of the concrete. In order to ensure the vibration effect, a high-frequency intelligent vibrator is used. The vibrator has a built-in sensor that can monitor the vibration density in real time to avoid over-vibration or missed vibration;

[0051] The specific operation of high side wall re-vibration is to roll the rolling tool from one end of the side wall at a constant speed along the side wall surface for 3-5 times. During the rolling process, keep the roller perpendicular to the concrete surface, and then use an ultrasonic transducer with a frequency between 20-100kHz for re-vibration. The ultrasonic transducers are evenly distributed around the side wall surface. The bottom plate and top arch formwork adopts curved wooden formwork, and the top arch formwork has an observation window. The formwork is fastened with a tie rod, and the tie rod adopts a prestressed tie rod with adjustable tension.

[0052] The construction joints are seamlessly connected. The verticality and curvature of the template are corrected by the total station and laser rangefinder, with an error of less than 1cm. The template support is in the order of "first the two ends and then the middle", and the density of the water stop and the template gap is 100kg / m 3 The above closed-cell foam glue is sealed, and the foam glue is evenly applied by an automatic glue coating machine. Expandable waterstop strips are used to seal the joints between the waterstop and the structure, the corners of the template joints, and the surroundings of the observation window.

[0053] See also Figure 1 , Figure 2 and Figure 4 , an embodiment provided by the present invention: a method for constructing mirror concrete lining on the flow surface of a complex-shaped high-flow-rate spillway tunnel, wherein the complex-shaped high-flow-rate spillway tunnel is subjected to on-site measurement and investigation of the shape, size, flood flow and water level, seismic peak acceleration and response spectrum characteristic period of the spillway tunnel, and three-dimensional scanning is performed using laser scanning technology, a measurement reference point is established at the spillway tunnel engineering site, a laser scanning device is placed at the measurement reference point, and each scanning station is relatively positioned by a positioning target ball / total station; a long and curved spillway tunnel is scanned in sections, and there is a certain overlap between each scanning area; during the scanning process, the three-dimensional coordinates and reflection intensity of each scanning point are synchronously recorded, and the data is wirelessly transmitted to a data storage device and a modeling software, and the scanning progress and some preliminary processed results are displayed in real time on the display screen of the scanning device;

[0054] The 3D modeling software uses laser scanning technology to obtain data to create a 3D model of the spillway tunnel. The 3D model includes the complex shape of the flow surface, lining structure, and steel bar arrangement. In the 3D model, the strength, elastic modulus, Poisson's ratio of concrete, and the strength and diameter of steel bars are given to different materials and structures; the 3D model is placed in the simulation software to set the parameters of the construction process; the concrete pouring process is simulated, the flow of concrete in the complex flow surface is observed, and the accumulation, voids, and cold joints of concrete are predicted. By adjusting the pouring speed and method, the flow performance of concrete is optimized to ensure that the concrete is evenly poured over the entire flow surface; based on the simulation results, the problems that may occur during the construction process (cracks, leakage, deformation) are predicted, and the causes of the problems (shrinkage of concrete) are analyzed. , temperature stress, water flow impact), and repeated simulation; the measurement points are measured along the axis using a total station, and monitoring points are set up inside and outside the tunnel to calibrate and verify the position of the template. The entire line is divided into 12 warehouses, each with a length of 12.1m. Each warehouse is equipped with at least 3 groups of cross-section measurement points. An automated control pad heightening system is used in the lining construction of the broken line. The protective layer uses concrete pads with a strength not less than that of the structure. The pads are fastened to the steel bars through buckles and are dispersedly arranged. The bottom plate adopts a trackless slipform casting process. The slipform machine is equipped with an automatic leveling and deviation correction system. The concrete lining of the pressure-free section tunnel is cast in the order of "side wall first, then top arch, and finally bottom plate". The side walls and top arch are cast using self-propelled hydraulic trolleys, and the trolleys are equipped with laser positioning systems.

[0055] The lining structure uses 3D design software to design the 3D printing model of the lining concrete, determine the printing material, speed and layer thickness of 70-90mm, plan the printing path and sequence, divide the lining concrete of the flow surface of the spillway into several modules, and assemble them using precast concrete slabs / precast concrete segments. The precast modules are mechanically connected to replicate the special texture / shape of the precast concrete slabs; the pouring of the top arch concrete starts from 2m below the arch line and pours upward to the arch top. The HTB90 concrete pump is used to pump the concrete into the warehouse. The concrete pump is equipped with an intelligent pumping control system. The pouring sequence is carried out in sequence, and the hard overlap method is strictly adopted. The overlap length is controlled at 3-5cm. During the overlap process, the vertical seams are inspected, polished, hemp-treated, cleaned, and affixed with transparent tape and double-sided tape;

[0056] The side wall is cast in a flat and symmetrical manner. First, a 20cm thick secondary mortar-rich concrete is laid, and a 100mm diameter high-frequency vibrator is used for compaction. The vibrator is equipped with an intelligent monitoring system. The thickness of each embryonic layer is 0.5m, and it is vibrated through the working window. The top arch concrete is fed through a 150mm diameter pumping window. The window position is pre-set on the template and the periphery is sealed with a sealing ring. The pouring is required to be continuous and fast, with a paving thickness of 30-40cm, and the material is laid symmetrically. When the sealing hole is slurry, the pouring is stopped in time;

[0057] The A100 vibrator is used for the first vibration, and the vibration time is 60 seconds; the A70 vibrator is used for the re-vibration, and the vibration time is 45 seconds, and the interval is 20 minutes. The spacing between the vibration points shall not exceed 1.5 times the effective vibration radius. The roughening of the cushion layer and the side wall shall be carried out after the anchor grouting and grouting. The roughening time is 8 to 12 hours after the warehouse is closed. A high-pressure water gun with a water pressure of 25MPa to 30MPa is used. The roughening depth reaches 2-3mm. The junction between the top of the side wall and the top arch is not roughened, and a riding edge protection less than 30mm is used.

[0058] Furthermore, laser scanning technology acquires data and transmits it to virtual simulation technology equipment. The virtual reality equipment is equipped with a virtual reality helmet and a handle. The virtual reality helmet is connected to the virtual simulation results to the construction workers and designers in an immersive way. Through the virtual reality equipment, users can truly observe the internal structure and construction process of the spillway tunnel, design the concrete construction process, and conduct 4D (3D model + time) simulation in combination with the construction schedule; simulate high-flow flood discharge scenarios, the impact of water on the tunnel wall, the formation of vortices, and cavitation. Users use the handle to open / close the gate and adjust the flood discharge flow. The virtual simulation results are uploaded to the cloud for sharing, and users can conduct cross-regional project collaboration and decision-making.

[0059] See also Figure 2 , Figure 4 and Figure 5 , an embodiment provided by the present invention: a method for constructing mirror concrete for the lining of the flow surface of a complex high-flow-rate flood discharge tunnel, wherein the steel bar production adopts a fully automatic CNC steel bar processing equipment, and the steel bar cutting, bending, and forming are completed in one, and the steel bar connection method is as follows:

[0060] For steel bars with a diameter of less than 25 mm, a flash butt welding machine is used for butt welding. The welding parameters are set by an intelligent control system to ensure welding quality.

[0061] For steel bars with a diameter greater than 25 mm, a straight thread connection method is used. A CNC thread rolling machine is used to roll straight threads on the ends of the steel bars. The connecting sleeve is made of alloy steel and has threads on the inner wall, which are tightly connected to the threads on the ends of the steel bars. A torque wrench is used to control the tightening torque of the connecting sleeve.

[0062] When installing the steel bars, the side wall steel bars are measured and laid out first, and the positioning is accurate. The vertical steel bars are erected at one time and fixed with steel bar positioning frames and clamps. The main bars of the inner wall and top arch are in the same direction as the side walls. An arc template is used to ensure the bending radius and positioning of the steel bars. The bottom plate steel bars are laid out according to the center line, side line and elevation control points. A welded grid sample frame is set up and a movable steel bar binding platform is used. The platform is equipped with a hydraulic lifting system and a mobile track. The top arch steel bars are installed on anchor rods. The anchor rods are constructed with an automated drilling machine. The steel bars are bent by pulling wires to form a sample frame, and the anchor rods are tightened at the same time. The reinforcement is used to stabilize the structure, the cross-seam reinforcement passes through the holes reserved in the head template, the gap is filled with calcium carbonate, and the joints are staggered; the embedded parts are constructed using an adjustable special-shaped purlin fixing template, the adjustable special-shaped purlin fixing template fixes the rubber water stop and the copper water stop, the joints of the rubber water stop are connected by a hot melt welding machine, the overlap length is ≥10cm, and the welding process is controlled by a temperature control system; the copper water stop specifications are 460mm / 600mm in width and 1.2mm in thickness, the copper water stop is welded using an argon arc welding machine, and the weld overlap length is ≥2cm;

[0063] Furthermore, for large-volume concrete, temperature control is the key to preventing cracks on the surface and an important step to ensure the appearance quality of mirror concrete. To this end, the following measures were taken:

[0064] Concrete materials: Use low-heat silicate cement to reduce the peak hydration heat. Optimize the gradation in the mix ratio, add high-efficiency water reducer and first-grade fly ash to reduce the unit cement dosage. The addition of nano materials such as nano silicon powder improves the density and strength of concrete and reduces the hydration heat. Cooling water is used in the concrete mixing process, and the water temperature is controlled below 5°C. Aggregates are sprayed with water to cool down before mixing, and covered with sunshade nets to prevent direct sunlight from heating up.

[0065] Construction technology: Avoid pouring during high temperature periods, and choose to construct at night or in the morning when the temperature is lower. Set up a sunshade at the pouring site, and use an automatic retractable sunshade system to automatically adjust the sunshade range according to the position of the sun. An intelligent spray cooling system is arranged on the pouring work surface, which monitors the ambient temperature in real time through a temperature sensor and automatically sprays cold mist to reduce the temperature. Industrial air coolers or air conditioners are arranged at corners, joints and gaps to reduce the ambient temperature and ensure that the temperature of concrete entering the mold meets the specification requirements.

[0066] Initial cooling of concrete: pre-buried cooling water pipes for internal cooling. The side wall section of the spillway tunnel adopts a "four-in-four-out" cooling water pipe layout. The cooling water pipes are pressure-resistant plastic pipes with a diameter of φ25mm. They are fixed in the steel skeleton when buried, and the spacing and position are in accordance with design requirements. The top arch section adopts a "two-in-two-out" cooling water pipe layout. The inlet and outlet of the cooling water pipe are equipped with flow control valves and temperature sensors, and the water flow and water temperature are adjusted through an intelligent monitoring system. In the low temperature season, the water flow rate is set to 2.5m 3 / h; in hot seasons, the water flow rate is increased to 4.0m 3 / h. The cooling water adopts a circulating water system with controllable water temperature. The circulating water is cooled by a cooling tower or refrigeration unit to ensure that the water temperature entering the cooling pipe is constant. The water temperature and concrete temperature are monitored in real time during the cooling process. The temperature data is transmitted wirelessly to the control center to automatically adjust the cooling parameters to prevent excessive temperature difference between the inside and outside of the concrete.

[0067] See also Figure 3 , Figure 4 and Figure 5 , an embodiment provided by the present invention: a method for constructing mirror concrete for the lining of the flow surface of a complex-shaped high-flow-rate flood discharge tunnel, wherein the side wall concrete is put into the warehouse using a large-slope heavy-load automatic material transportation system; the large-slope heavy-load automatic material transportation system includes a loading component, a power and drive component, an automatic control component, and a hopper and unloading component; the belt conveyor is connected to the power and drive component through a sprocket, the automatic control component controls the power and drive component through a PLC, and the power and drive component is connected to the hopper and unloading component through a mechanical arm; a weighing sensor and a speed sensor are fixedly installed inside the belt conveyor, the loading component adopts a 10kV / 1400kW variable frequency drive belt conveyor, the belt width is 1.2m, and the belt adopts aramid fiber / carbon fiber; the power component is equipped with a shock-absorbing roller, a shock-absorbing spring / rubber shock absorber is fixedly installed inside the shock-absorbing roller, and limit elements are installed at both ends of the shock-absorbing roller;

[0068] Concrete is transported to the site by a mixer truck from the mixing station. On site, an automated control system backhoe loader is used to shovel concrete into the belt conveyor of the feeding system. An anti-overflow baffle is installed at the joint between the backhoe loader bucket and the belt conveyor. The belt width of the feeding system is 1.2m. The belt conveyor is equipped with a weighing sensor and a speed sensor. The concrete is transported to the transfer system on the top of the steel mold trolley through the belt conveyor. The transfer system consists of a rotatable distributor. The top transfer system delivers the concrete into the bin. The entire process is coordinated by the PLC automatic control system. The vertical height of the concrete falling in the bin should be controlled within 1 .5m or less. When the height exceeds this, a chute / slow-down trough is added. The concrete pouring is additionally vacuum treated. The vacuum treatment is mainly carried out by installing a vacuum pipe on the composite formwork. Small air extraction holes are opened on the composite formwork. The vacuum pump and the composite formwork are connected by vacuum pipes and connecting pipes. There are impellers and working fluids inside the vacuum pump. The impeller rotates in the pump cavity. The working fluid forms a rotating liquid ring. The liquid ring and the impeller blades form a periodically changing volume. The vacuum pump generates negative pressure. The vacuum tank stores the extracted air and part of the water vapor. The vacuum degree is controlled between -0.06 and -0.08MPa.

[0069] Furthermore, in low-temperature seasons, "temperature control of concrete mixing + heat preservation during transportation + heating of the pouring environment" and in high-temperature seasons, "cooling of concrete mixing + cooling water temperature control during warehouse pouring" are used to ensure normal concrete pouring. The impact-resistant and wear-resistant concrete of the side walls, top arches and bottom plates of the standard section of the water discharge structure are respectively put into the warehouse by the steel formwork trolley's own lifting system + belt conveyor, pumping method and telescopic belt conveyor + pumping method. After handing in a high-quality report card for the concrete construction of the standard section, the builders began to challenge the chute section. The chute section has a large drop and a longitudinal slope of about 18°. The terrain is steep and mountainous, with deep valleys, narrow construction sites, difficult construction arrangements, and extremely difficult concrete transportation and construction organization. To this end, the chute is constructed in sections from downstream to upstream in the order of side walls first and bottom plates later. The bottom plate is constructed by the method of "tower crane feeding + belt conveyor feeding + distributor entering the warehouse + slipform circulation construction". This method greatly increases the proportion of normal concrete pouring and effectively ensures the quality of the project.

[0070] Process special concrete edge protection tools to protect the performance and shape of the finished concrete; increase the frequency of concrete sampling, and perform on-site curing. Demoulding is allowed only after the concrete reaches the strength specified in the specification; after the concrete is demolded, hang geotextile on its surface, and use 20℃~25℃ warm water sprinkling to maintain moisture retention before the maximum temperature of the concrete appears, and use room temperature water spraying to maintain moisture retention after the maximum temperature.

[0071] See also Figure 2 , Figure 3 and Figure 5, an embodiment provided by the present invention: a method for constructing mirror concrete for the lining of the flow surface of a complex-shaped high-flow-rate spillway tunnel, wherein the temperature control system adopts a phase change material temperature control technology, and during the concrete mixing process, 5%-15% of microencapsulated paraffin phase change materials, admixtures and first-class fly ash are added to low-heat silicate cement in a volume ratio to reduce the unit cement dosage and ultimately control the concrete hydration heat; avoid pouring during high temperature periods, use a sunshade and a heat preservation device, and at the same time use spraying / arranging an air conditioner to reduce the ambient temperature of the pouring working surface to reduce the concrete pouring temperature, apply a layer of heat insulation coating on the concrete surface, the heat insulation coating adopts a ceramic-based heat insulation coating, and a large number of tiny pores inside the heat insulation coating prevent heat conduction; the initial cooling of the concrete is carried out by pre-buried cooling water pipes and cooling water cooling, the side wall section of the spillway tunnel adopts a "four-in-four-out" form to arrange cooling water pipes, and the top arch section adopts a "two-in-two-out" form to arrange cooling water pipes, and the water flow rate in the low temperature season is 2.5m 3 / h, the water flow rate in high temperature season is 4.0m 3 / h;

[0072] Multiple sedimentation tanks are built at the construction site. Wastewater first flows into the primary sedimentation tank to remove larger suspended solids through natural sedimentation. The primary sedimentation time is not less than 2 hours. After the primary sedimentation, the wastewater flows into the secondary sedimentation tank. Sand filter / activated carbon is added to the secondary sedimentation tank to remove fine suspended solids. The secondary sedimentation tank adopts an inclined plate sedimentation tank. The sedimentation tank is equipped with an automatic pH adjustment system. The pH sensor monitors the pH value of the wastewater and transmits the signal to the controller. The controller controls the dosing device to add a neutralizer to the wastewater according to the set pH value range (6-8);

[0073] Furthermore, firstly, a concrete curing agent with good film-forming properties is selected. This curing agent can form a sealed film on the surface of concrete to prevent the evaporation of water. For example, a water-based polymer emulsion curing agent can form a continuous, non-porous film on the surface of the side wall concrete, reducing the rate of water loss inside the concrete. After the concrete construction is completed, the curing agent is promptly applied to the surface of the side wall concrete evenly with a sprayer or a special brushing tool. The thickness is generally controlled within the specified range to ensure that it works effectively. An intelligent spray system is installed inside the flood discharge tunnel. By setting spray nozzles around the side wall, the nozzles can automatically adjust the spray frequency and water volume according to the ambient temperature, humidity and data from the humidity sensor inside the concrete. When the ambient temperature is high and the humidity is low, and the humidity inside the concrete drops to a certain threshold, the intelligent spray system will automatically start spraying. The sprayed water can be treated neutral water to avoid the adverse effects of impurities in the water on the concrete. In addition, the spray system can set different spray modes, such as atomization mode, so that the sprayed water is in a fine mist. At the same time, the intelligent spray system can also be connected to a remote monitoring system. Engineering technicians can remotely monitor the operating status of the spray system and the humidity data on the concrete surface and inside through mobile phone applications or computer software.

[0074] Working principle, 5 process tests and 4 simulations were carried out on site, and it was determined that the (10mm+2mm) composite steel formwork was used for pouring concrete on the side walls of the flood discharge tunnel to meet the mirror effect. The concrete construction parameters are: C9040W8F150 grade, slump 70-90mm, loose paving 0.45m, initial vibration 60s, re-vibration 45s, interval 20min, vibration point square or plum blossom arrangement, 0.3m spacing. The side formwork of the trolley head template is 15cm away from the structure, and an observation window is reserved for the top arch. After installation, the tie rod is tightened, and the verticality is adjusted to an error of less than 1cm. The support sequence is first at both ends and then in the middle. The water stop and template joints are sealed with foam glue. Use a total station to measure along the axis, and set points inside and outside the tunnel to calibrate and verify the template. The side walls and top arches are cast using trolleys, divided into 12 warehouses, each warehouse is 12.1m, and each warehouse has at least 3 groups of section points. The lining of the broken line is raised with pads and the bottom plate is cast with trackless sliding formwork. The concrete lining of the non-pressure section of the tunnel body is cast in the order of "side wall first, then top arch, and then bottom plate". The steel bars are made and installed, and the rubber water stop joints are hot-melt connected, with an overlap of ≥10cm to ensure impermeability. During casting, the formwork is fixed with special-shaped purlins to prevent the water stop from being misplaced. The lining concrete of the flood discharge tunnel is equipped with red copper water stop, the circumferential construction joints are roughened, and the structural steel bars are passed through the joints. During the construction of the structural joints, 2cm thick asphalt wood boards are embedded on the outside of the red copper, emulsified asphalt is applied to the joint surface, and epoxy mortar is applied to the water-facing surface. The top arch concrete is cast from 2m below the arch line to the top of the arch. The vertical height of the concrete falling in the warehouse should be controlled within 1.5m. The casting sequence is carried out in sequence, and the hard overlap method is strictly adopted. The overlap length is controlled at 3-5cm. Strict attention should be paid to the vertical joint inspection, grinding, hemp treatment, cleaning, transparent tape and double-sided tape and other overlap treatment methods. Concrete pouring of side wall: First, lay 20cm thick secondary mortar-rich concrete and vibrate it with a φ100 vibrator. Use the flat pouring method and symmetrical pouring. The top arch concrete is fed through the Φ150 pumping window, continuously and quickly, and the material is laid 30-40cm thick, symmetrically, and the pouring is stopped when the hole is sealed. The flushing of the cushion layer and side wall is carried out after the anchor grouting and grouting. The flushing time is generally 8 to 12 hours after the warehouse is closed, and the water pressure is 25MPa to 30Mpa. The junction between the top of the side wall and the top arch is not flushed, and a <30mm riding edge protection is used, and finally temperature control is performed.

[0075] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

Claims

1. A method for constructing mirror concrete lining on the flow surface of a complex high-velocity flood discharge tunnel, characterized in that: Including processability test, shape automatic deformation template processing, point measurement, steel bar production and installation, embedded parts construction, concrete warehousing and pouring; Five process tests and four simulations were conducted on site. The concrete pouring of the side wall of the spillway tunnel used a composite steel formwork composed of a 10mm thick steel plate and a 2mm thick stainless steel plate. The concrete construction parameters were: C9040W8F150 grade, slump 70-90mm, loose paving 0.45m, initial vibration 60s, re-vibration 45s, interval 20min, vibration point square / plum blossom arrangement, 0.3m spacing; microcapsules containing repair agents, bacteria and enzymes were added to the concrete. Microcapsules containing epoxy resin / polyurethane were used. The microcapsules automatically repaired cracks with a width of less than 0.2mm. Bacteria and enzymes decomposed the surrounding substances to produce calcium carbonate to fill the cracks. Temperature sensors, strain sensors and pressure sensors were buried in the lining structure. The template uses a CNC cutting machine to cut the steel plate, and the steel plate and the stainless steel plate are automatically welded by a robot welding system. After welding, the template surface is precisely polished using a CNC grinder.

2. The method for constructing mirror concrete for the flow surface lining of a complex-shaped high-velocity flood discharge tunnel according to claim 1 is characterized in that: The shape automatic deformation template processing adopts automatic deformation of a preset shape, the trolley head template adopts a bulk modified combined template, a memory alloy structure is arranged inside the template, the shape automatic deformation template is woven by polyurethane and Ni-Ti alloy wire / sheet, the polyurethane material is added with a chain extender to form a thin sheet combined with a rigid frame, the Ni-Ti shape memory alloy is melted and forged to form the Ni-Ti alloy wire / sheet, the side mold distance structure is 15cm, the bottom plate and the top arch template adopt a wooden mold, the top arch has an observation window reserved, the prestressed pull rod is tightened after installation, the verticality is adjusted to an error of less than 1cm, the support sequence is first the two ends and then the middle, the water stop and the template seam are sealed with foam glue, and the corners, joints and gaps are made of epoxy resin / polyurethane microcapsules.

3. The method for constructing mirror concrete for the flow surface lining of a complex-shaped high-velocity flood discharge tunnel according to claim 1 is characterized in that: The complex-shaped high-flow-rate spillway tunnel is subjected to field measurement and investigation of the shape, size, flood flow and water level, seismic peak acceleration and response spectrum characteristic period of the spillway tunnel, and three-dimensional scanning is performed using laser scanning technology. A measurement reference point is established at the spillway tunnel engineering site, and the laser scanning equipment is placed at the measurement reference point. Each scanning station is relatively positioned by a positioning target ball / total station. The long and curved spillway tunnel is scanned in sections, and there is a certain overlap between each scanning area. During the scanning process, the three-dimensional coordinates and reflection intensity of each scanning point are synchronously recorded, and the data is wirelessly transmitted to the data storage device and the modeling software. At the same time, the scanning progress and some preliminary processed results are displayed in real time on the display screen of the scanning device. The 3D modeling software uses laser scanning technology to obtain data to create a 3D model of the spillway tunnel. The 3D model includes the complex shape of the flow surface, lining structure, and steel bar arrangement. In the 3D model, the strength of the concrete, elastic modulus, Poisson's ratio, and the strength and diameter of the steel bar are given to different materials and structures; the 3D model is placed in the simulation software to set the parameters of the construction process; the concrete pouring process is simulated, the flow of concrete in the complex-shaped flow surface is observed, and the accumulation, voids, and cold joints of concrete are predicted. By adjusting the pouring speed and method, the flow properties of concrete are optimized to ensure that the concrete is evenly poured over the entire flow surface; based on the simulation results, possible problems (cracks, leakage, deformation) that may arise during the construction process are predicted, the causes of the problems (concrete shrinkage, temperature stress, water flow impact) are analyzed, and the simulation is repeated.

4. The method for constructing mirror concrete for the flow surface lining of a complex-shaped high-velocity spillway tunnel according to claim 1 is characterized in that: The measurement points are measured along the axis using a total station, and monitoring points are set up inside and outside the tunnel to calibrate and verify the position of the template. The entire line is divided into 12 warehouses, each with a length of 12.1m. Each warehouse is equipped with at least 3 groups of cross-section measurement points. An automated control pad heightening system is used in the lining construction of the broken line. The protective layer uses concrete pads with a strength not less than that of the structure. The pads are fastened to the steel bars through buckles and are dispersedly arranged. The bottom plate adopts a trackless slipform casting process. The slipform machine is equipped with an automatic leveling and deviation correction system. The concrete lining of the pressureless tunnel body is cast in the order of "side wall first, then top arch, and finally bottom plate". The side walls and top arch are cast using self-propelled hydraulic trolleys, respectively, and the trolleys are equipped with laser positioning systems. The lining structure uses 3D design software to design the 3D printing model of the lining concrete, determine the printing material, speed and layer thickness of 70-90mm, plan the printing path and sequence, divide the lining concrete of the spillway flow surface into several modules, and assemble them using precast concrete slabs / precast concrete segments. The precast modules are mechanically connected to replicate the special texture / shape of the precast concrete slabs.

5. The method for constructing mirror concrete for the flow surface lining of a complex-shaped high-flow-rate spillway tunnel according to claim 4 is characterized in that: The steel bar production adopts fully automatic CNC steel bar processing equipment, and the steel bar cutting, bending and forming are completed in one. The steel bar connection method is as follows: For steel bars with a diameter of less than 25 mm, a flash butt welding machine is used for butt welding, and the welding parameters are set by the intelligent control system; For steel bars with a diameter greater than 25 mm, a straight thread connection method is used. A CNC thread rolling machine is used to roll straight threads on the ends of the steel bars. The connecting sleeve is made of alloy steel, with threads on the inner wall, which is tightly connected to the threads on the ends of the steel bars. Use a torque wrench to control the tightening torque of the connecting sleeve; When installing the steel bars, the side wall steel bars are first measured and laid out to ensure accurate positioning. The vertical steel bars are erected at one time and fixed with steel bar positioning frames and clamps. The main bars of the inner walls and top arches are in the same direction as the side walls. An arc-shaped template is used to ensure the bending radius and positioning of the steel bars. The bottom plate steel bars are laid out according to the center line, side lines and elevation control points. A welded grid sample frame is set up and a movable steel bar binding platform is used. The platform is equipped with a hydraulic lifting system and mobile tracks. The top arch steel bars are installed on anchor rods, which are constructed using an automated drilling machine. The steel bars are bent by pulling wires to form a sample frame. At the same time, the anchor rod reinforcement is increased to stabilize the structure. The seam steel bars pass through the holes reserved in the head template. The gaps are filled with calcium carbonate and the joints are staggered.

6. The method for constructing mirror concrete for the flow surface lining of a complex-shaped high-velocity flood discharge tunnel according to claim 1 is characterized in that: The embedded parts are constructed using an adjustable special-shaped purlin fixing template, which fixes the rubber waterstop and the copper waterstop. The joints of the rubber waterstop are connected using a hot melt welding machine, with an overlap length of ≥10cm, and the welding process is controlled by a temperature control system. The specifications of the copper waterstop are 460mm / 600mm in width and 1.2mm in thickness. The copper waterstop is welded using an argon arc welding machine, with a weld overlap length of ≥2cm.

7. The method for constructing mirror concrete for the flow surface lining of a complex-shaped high-velocity flood discharge tunnel according to claim 1 is characterized in that: The side wall concrete is fed into the warehouse using a large-slope heavy-load automatic material transport system; the large-slope heavy-load automatic material transport system includes a loading component, a power and drive component, an automatic control component, and a hopper and unloading component; the belt conveyor is connected to the power and drive component through a sprocket, the automatic control component controls the power and drive component through a PLC, and the power and drive component is connected to the hopper and unloading component through a mechanical arm; a weighing sensor and a speed sensor are fixedly installed inside the belt conveyor, the loading component uses a 10kV / 1400kW variable frequency drive belt conveyor, the belt width is 1.2m, and the belt is made of aramid fiber / carbon fiber; the power component is equipped with a shock-absorbing roller, a shock-absorbing spring / rubber shock absorber is fixedly installed inside the shock-absorbing roller, and limit elements are installed at both ends of the shock-absorbing roller; The concrete is transported to the site by a mixer truck from the mixing station. On site, an automated control system backhoe loader is used to shovel the concrete into the belt conveyor of the feeding system. An anti-overflow baffle is installed at the joint between the backhoe loader bucket and the belt conveyor. The belt width of the feeding system is 1.2m. The belt conveyor is equipped with a weighing sensor and a speed sensor. The concrete is transported to the transfer system on the top of the steel mold trolley through the belt conveyor. The transfer system consists of a rotatable distributor. The top transfer system delivers the concrete into the bin. The entire process is coordinated by the PLC automatic control system. The vertical height of the concrete falling in the bin should be controlled within 1.5m. When this height is exceeded, a chute / slow-down chute should be added.

8. The method for constructing mirror concrete for the flow surface lining of a complex-shaped high-velocity flood discharge tunnel according to claim 1 is characterized in that: The pouring of the top arch concrete starts from 2m below the arch line and pours upward to the arch top. The HTB90 concrete pump is used to pump the concrete into the warehouse. The concrete pump is equipped with an intelligent pumping control system. The pouring sequence is carried out in sequence. The hard overlap method is strictly adopted, and the overlap length is controlled at 3 to 5cm. During the overlap process, the vertical seam is inspected, polished, hemp-treated, cleaned, and affixed with transparent tape and double-sided tape; The side wall is cast in a flat and symmetrical manner. First, a 20cm thick secondary mortar-rich concrete is laid, and a 100mm diameter high-frequency vibrator is used for compaction. The vibrator is equipped with an intelligent monitoring system. The thickness of each embryonic layer is 0.5m, and it is vibrated through the working window. The top arch concrete is fed through a 150mm diameter pumping window. The window position is pre-set on the template and the periphery is sealed with a sealing ring. The pouring is required to be continuous and fast, with a paving thickness of 30-40cm, and the material is laid symmetrically. When the sealing hole is slurry, the pouring is stopped in time; The A100 vibrator is used for the first vibration with a vibration time of 60 seconds; the A70 vibrator is used for the re-vibration with a vibration time of 45 seconds, and the vibration is carried out at intervals of 20 minutes. The spacing between vibration points shall not exceed 1.5 times the effective vibration radius. The roughening of the cushion layer and side walls shall be carried out after the grouting of anchor bars. The roughening time is 8 to 12 hours after closing. A high-pressure water gun with a water pressure of 25MPa to 30MPa is used. The roughening depth reaches 2-3mm. The top of the side wall and the top arch are not roughened, and a riding edge protection of less than 30mm is used.

9. The method for constructing mirror concrete for the flow surface lining of a complex-shaped high-flow-rate spillway tunnel according to claim 3 is characterized in that: The concrete pouring is additionally vacuum treated. The vacuum treatment is mainly performed by installing a vacuum pipe on the composite formwork. Small exhaust holes are opened on the composite formwork. The vacuum pump and the composite formwork are connected by vacuum pipes and connecting pipes. An impeller and a working fluid are arranged inside the vacuum pump. The impeller rotates in the pump chamber. The working fluid forms a rotating liquid ring. The liquid ring and the impeller blades form a periodically changing volume. The vacuum pump generates negative pressure. The vacuum tank stores the extracted air and part of the water vapor. The vacuum degree is controlled between -0.06 and -0.08 MPa.

10. The method for constructing mirror concrete for the flow surface lining of a complex-shaped high-velocity flood discharge tunnel according to claim 6, characterized in that: The temperature control system adopts phase change material temperature control technology. During the concrete mixing process, 5%-15% of microencapsulated paraffin phase change materials, admixtures and first-grade fly ash are added to low-heat silicate cement to reduce the unit cement dosage and ultimately control the concrete hydration heat. The pouring is avoided during high temperature periods. A sunshade and a heat preservation device are used. At the same time, the ambient temperature of the pouring working surface is reduced by spraying / arranging air conditioners to reduce the concrete pouring temperature. A layer of heat insulation coating is applied on the concrete surface. The heat insulation coating adopts a ceramic-based heat insulation coating. There are a large number of tiny pores inside the heat insulation coating to prevent heat conduction. The initial cooling of the concrete is carried out by pre-buried cooling water pipes and cooling water cooling. The side wall section of the flood discharge tunnel adopts a "four-in-four-out" form to arrange the cooling water pipes, and the top arch section adopts a "two-in-two-out" form to arrange the cooling water pipes. The water flow rate in the low temperature season is 2.5m 3 / h, the water flow rate in high temperature season is 4.0m 3 / h; Multiple sedimentation tanks are built at the construction site. Wastewater first flows into the primary sedimentation tank, where larger suspended solids are removed through natural sedimentation. The primary sedimentation time is no less than 2 hours. After the primary sedimentation, the wastewater flows into the secondary sedimentation tank. Sand filter / activated carbon is added to the secondary sedimentation tank to remove fine suspended solids. The secondary sedimentation tank adopts an inclined plate sedimentation tank. The sedimentation tank is equipped with an automatic pH adjustment system. The pH sensor monitors the pH value of the wastewater and transmits the signal to the controller. The controller controls the dosing device to add a neutralizer to the wastewater according to the set pH value range (6-8).

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