Construction method for temperature control and crack prevention of mass concrete of wind turbine foundation

Abstract

The present application relates to the technical field of building construction, in particular to a wind turbine foundation mass concrete temperature control and crack prevention construction method, comprising: steel mesh, circulating cooling system, flow regulating component, stress feedback component and external adjusting component, the method specifically comprises the following steps. The mechanical linkage of the stress feedback component and the flow regulating component realizes double protection: even if the internal temperature of the concrete has not reached the phase transition temperature, when the concrete generates huge tensile stress due to constraints, the stress is transmitted to the rotating rod through the reinforcing steel bar, the small tensile deformation of the reinforcing steel bar is enlarged to significant displacement by the lever principle of the rotating rod, the push ring and the lifting cover are forced to move upwards, the large-flow heat dissipation is opened in advance in the critical state before the crack occurs, the crack prevention blind area of the temperature not exceeding the standard but the stress exceeding the limit is eliminated, and the cracking is prevented.

Description

Technical Field

[0001] This invention relates to the field of building construction technology, specifically to a method for temperature-controlled and crack-preventing construction of large-volume concrete for wind turbine foundations in wind farms. Background Technology

[0002] As the core load-bearing component supporting the upper tower and blades, the wind turbine foundation is typically constructed using large-volume concrete casting. Due to the large volume of concrete, thick structural dimensions, and dense reinforcement of the wind turbine foundation, it is highly susceptible to significant temperature and shrinkage stresses under the combined effects of hydration heat release and external temperature differences. When the internal tensile stress exceeds the tensile strength of the concrete, it can lead to through-cracks or surface cracks, seriously threatening the long-term durability and structural safety of the wind turbine foundation.

[0003] Currently, the main temperature control and crack prevention measures for large-volume concrete foundations for wind turbines are: covering the concrete surface with insulation material to slow down the heat dissipation rate, and pre-embedding cooling water pipes inside, using external water pumps to circulate water and remove the heat of hydration.

[0004] However, existing cooling water flow regulation methods mostly rely on feedback data from embedded temperature sensors, with construction personnel manually or semi-automatically adjusting valve openings. Because large-volume concrete conducts heat slowly, temperature monitoring data often lags behind actual thermal stress development, leading to frequent instances of "overcooling" or "undercooling." Overcooling exacerbates the internal and external temperature difference, triggering new temperature cracks, while undercooling fails to effectively reduce peak temperature rises, making crack prevention difficult to guarantee. Summary of the Invention

[0005] The purpose of this invention is to provide a method for temperature-controlled crack prevention construction of large-volume concrete for wind turbine foundations in wind farms, so as to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a method for temperature-controlled crack prevention construction of large-volume concrete for wind turbine foundations in wind farms, comprising: wire mesh, a circulating cooling system, a flow regulating component, a stress feedback component, and an external adjustment component, wherein the method specifically includes the following steps; S1. Construction preparation: Based on the dimensions of the large-volume concrete structure of the wind turbine foundation and the environmental conditions, conduct temperature field and stress field simulation calculations, determine the temperature control index and the layout scheme of the circulating cooling system, and lay the steel cage. S2. Concrete pouring: A layered continuous pouring process is adopted to control the thickness of each layer and the time interval between the upper and lower layers. S3. Internal water cooling: During the pouring process, steel wire mesh and a circulating cooling system are embedded simultaneously. After the concrete has initially set, water is circulated through the circulating cooling system to cool the inside of the concrete foundation. The flow regulating component is set at the inner end of the circulating cooling system. The flow regulating component automatically adjusts the cooling water flow rate according to the temperature inside the concrete foundation to perform adaptive heat dissipation control. S4. Internal stress feedback: During the pouring process, a stress feedback component is pre-embedded. One end of the stress feedback component is inserted into the flow regulating component, and the other end is rigidly connected to the steel cage. The stress feedback component is used to adaptively regulate the heat dissipation of the tensile stress inside the concrete foundation. S5. External thermal insulation and moisture retention: After the concrete has set, cover the external adjustment components in a timely manner, and dynamically adjust the thickness of the insulation layer or spray cooling water according to changes in ambient temperature and concrete surface temperature.

[0007] This invention also includes the following technical features: In one embodiment of the present invention, the temperature control indicators in step S1 include: concrete pouring temperature ≤30℃, maximum internal temperature of concrete ≤70℃, temperature difference between inside and outside concrete ≤25℃, and concrete cooling rate ≤2℃ / d.

[0008] In one embodiment of the present invention, the circulating cooling system in step S3 includes a circulating water pipe, which is coiled inside the concrete foundation and fixed above the reinforcing cage. One end of the circulating water pipe is connected to an inlet pipe through an installation pipe, and the other end of the circulating water pipe is fixedly installed with an outlet pipe. The ends of the inlet pipe and the outlet pipe that are away from the circulating water pipe are both located outside the concrete foundation.

[0009] In one embodiment of the present invention, the circulating water pipe includes an inner pipe, one end of which is fixedly connected and communicates with an installation pipe, and the other end of which is fixedly connected and communicates with an outlet pipe. A plurality of outer pipes and protruding pipes are fixedly connected to the outer end of the inner pipe. The outer pipes and protruding pipes are arranged in a crisscross pattern. The outer pipes are filled with a solid-liquid phase change material. An inlet valve is fixedly installed on the side wall of the protruding pipe near the inlet pipe, and a one-way outlet valve is fixedly installed on the side wall of the protruding pipe near the outlet pipe.

[0010] In one embodiment of the present invention, the flow regulating component in step S3 includes an regulating block. The regulating block is annular and fixed on the inner wall of the mounting pipe. The outer side wall of the regulating block has a plurality of water outlet holes arranged in a circle. A plurality of temperature conducting components are uniformly fixedly installed inside the regulating block. A lifting cover is installed on the upper end of the temperature conducting components through a second telescopic rod. A thermal spring is installed inside the second telescopic rod. When the thermal spring is heated and elongated, it pushes the lifting cover and the upper end of the regulating block to separate, so that the flow cross-sectional area of ​​the mounting pipe increases with the increase of temperature. When the cross-sectional area of ​​the cooling water flow in the installation pipe increases, the water pressure of the cooling water in the inner pipe increases, and the inlet valve is opened, allowing the cooling water to enter the convex pipe. After flowing in the convex pipe, the cooling water is discharged into the inner pipe through the one-way outlet valve.

[0011] In one embodiment of the present invention, the temperature-conducting component includes a fixing strip made of heat-insulating material. The fixing strip is fixed inside the adjusting block, and a heat-conducting block is fixedly installed at one end of the fixing strip. The heat-conducting block is embedded in the outer end of the adjusting block. The other end of the fixing strip is located inside the inner ring of the adjusting block. A heat-conducting strip is fixedly installed inside the fixing strip. One end of the heat-conducting strip is fixedly connected to the heat-conducting block, and the other end is fixedly connected to a thermal spring.

[0012] In one embodiment of the present invention, the wire mesh has two sides, and when pouring concrete, the two layers of wire mesh are respectively laid on the upper and lower ends of the circulating water pipe.

[0013] In one embodiment of the present invention, the stress feedback component in step S4 includes a sleeve, a rotating rod and a push ring. Multiple sleeves and rotating rods are provided. One end of the sleeve is obliquely fixed on the outer wall of the connection between the circulating water pipe and the installation pipe, and penetrates the side wall of the circulating water pipe. The push ring is located inside the inner ring of the adjusting block, and the upper end of the push ring is fixed to the lower end of the lifting cover by a connecting column. One end of the rotating rod rotates within the adjusting block via a torsion spring and is connected to a ball head via an adjusting assembly. The upper outer wall of the ball head slides in contact with the lower outer wall of the push ring. The other end of the rotating rod is inserted into the sleeve and fixedly connected to the reinforcing cage.

[0014] In one embodiment of the present invention, the adjusting assembly includes a fixed cylinder fixed to the upper end of the rotating rod, a movable rod slidably connected inside the fixed cylinder, the movable rod being fixed by bolts, and the upper end of the movable rod being fixedly connected to the lower end of the ball head.

[0015] In one embodiment of the present invention, the external adjustment component in step S4 includes a water bladder, an inflatable air bladder is fixedly installed at the lower end of the water bladder, and a plurality of round tubes are uniformly fixedly installed at the lower end of the air bladder, the inner port of the round tubes being connected to the interior of the water bladder through a connecting pipe.

[0016] Compared with the prior art, the beneficial effects of the present invention are: This invention achieves dual protection through the mechanical linkage of the stress feedback component and the flow regulation component: even if the internal temperature of the concrete has not yet reached the phase change temperature, when the concrete generates huge tensile stress due to constraint, the stress is transmitted to the rotating rod through the steel bar. Utilizing the lever principle of the rotating rod, the small tensile deformation of the steel bar is amplified into a significant displacement, forcibly pushing the push ring and the lifting cover to move upward. This opens up a large flow of heat dissipation in advance at the critical state before cracks occur, eliminating the crack prevention blind zone where the temperature has not exceeded the standard but the stress has exceeded the limit, thus preventing cracking. This invention utilizes a thermal spring and mechanical lever structure, completely eliminating the dependence on external power supply and electronic sensors. When the temperature reaches the set value, the thermal spring automatically extends to push open the valve; after the temperature drops, it automatically resets, eliminating the hours-level lag error caused by traditional manual temperature measurement and manual valve adjustment. The circulating water pipe integrates phase change materials and variable flow control. The solid-liquid phase change material inside the outer pipe absorbs heat and melts during the peak of hydration heat, slowing down the rate of heat transfer to the cooling water. When the temperature drops sharply at night, it solidifies and releases heat, smoothing out temperature fluctuations between the inside and outside and avoiding the surface cold shock problem that is common in traditional water cooling. After the lifting cover is opened due to temperature or stress, the water flow cross-sectional area increases and the water pressure rises, pushing open the inlet valve to allow cooling water to enter the convex pipe for powerful heat exchange. This achieves an automatic control mode, which reduces the peak temperature rise and avoids secondary temperature stress caused by excessively rapid cooling. By laying external adjustment components on the concrete surface, the tedious work of frequent manual watering required by traditional geotextile covering is replaced, ensuring the continuity and uniformity of curing. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the invention and the main concrete structure. Figure 2 This is a perspective view of the overall structure of the present invention; Figure 3 This is a schematic diagram of the steel wire mesh and circulating water pipe structure of the present invention; Figure 4 This is a schematic diagram of the cross-section of the circulating water pipe of the present invention; Figure 5 This is a schematic diagram of the cross-sectional structure of the water inlet valve of the present invention; Figure 6 This is a schematic diagram showing the connection between the installation pipe, the circulating water pipe, and the inlet pipe of the present invention; Figure 7 This is a schematic diagram of the cross-sectional structure of the installation pipe and the water inlet pipe of the present invention; Figure 8 For the present invention Figure 7 Enlarged view of the structure of region A in the middle; Figure 9 This is a schematic cross-sectional view of the flow regulating component of the present invention; Figure 10 This is a schematic diagram of the external adjustment component structure of the present invention; Figure 11 This is a schematic cross-sectional view of the external adjustment component of the present invention; Figure 12 This is a schematic diagram of the installation of the stress feedback component of the present invention; Figure 13 This is a bottom view of the stress feedback component of the present invention; Figure 14 This is a schematic diagram of the internal structure of the adjusting block of the present invention; Figure 15 This is an enlarged view of the internal structure of the adjusting block of the present invention.

[0018] In the picture: 10. Wire mesh; 20. Circulating water pipe; 201. Inner pipe; 202. Outer pipe; 203. Convex pipe; 204. Solid-liquid phase change material; 205. Inlet valve; 2051. Support rod; 2052. Circular plate; 2053. First telescopic rod; 2054. Sealing cap; 2055. Return spring; 206. One-way outlet valve; 21. Mounting pipe; 22. Inlet pipe; 23. Outlet pipe; 30. Adjusting block; 31. Water outlet; 32. Protective cover; 33. Fixing strip; 331. Heat-conducting strip; 332. Heat-conducting block; 34. Second telescopic rod; 35. Thermal spring; 36. Lifting cover; 40. Sleeve; 401. Shaft; 41. Rotating rod; 42. Push ring; 43. Connecting post; 44. Fixed cylinder; 45. Moving rod; 46. Ball head; 50. Water bladder; 501. Water injection pipe; 51. Air bladder; 52. Connecting pipe; 53. Round pipe; 54. Anti-clogging plate; 55. Water outlet; 60. Concrete foundation. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of the present invention clear and complete, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only some, not all, embodiments of the present invention, and are merely illustrative of the embodiments of the present invention. They are not intended to limit the embodiments of the present invention. All other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] Please see Figures 1 to 15 The present invention provides a technical solution: a method for temperature control and crack prevention construction of large-volume concrete for wind turbine foundations in wind farms, including a wire mesh 10, a circulating cooling system, a flow regulating component, a stress feedback component, and an external adjustment component. The method specifically includes the following steps. S1. Construction Preparation: Based on the dimensions of the large-volume concrete structure of the wind turbine foundation and environmental conditions, temperature and stress field simulation calculations were performed to determine the temperature control parameters and the layout scheme of the circulating cooling system. Reinforcing cages were then laid. The temperature control parameters included: concrete pouring temperature ≤30℃, maximum internal concrete temperature ≤70℃, internal and external temperature difference ≤25℃, and concrete cooling rate ≤2℃ / d. Midas FEA software was used for temperature field simulation to determine the following temperature control parameters: pouring temperature ≤28℃, maximum internal temperature ≤68℃, internal and external temperature difference ≤23℃, and cooling rate ≤1.8℃ / d. Φ42×2.5mm HDPE pipes were used for cooling, with a horizontal spacing of 90cm and a serpentine layout. S2. Concrete pouring: A layered continuous pouring process is adopted, controlling the thickness of each layer and the time interval between covering the upper and lower layers. A sunshade is set up in the aggregate stockpile, and the temperature is sprayed to 26℃. Ice is added to the mixing water, the outlet temperature is 24.5℃, and the placement temperature is 27.2℃. A pushing type continuous pouring is adopted, with each layer being 40cm thick. The covering interval is controlled within 4 hours (initial setting time is 6 hours). The vibrator is inserted 5cm into the lower layer. S3. Internal Water Cooling: During the pouring process, a wire mesh 10 and a circulating cooling system are simultaneously embedded. After the concrete initially sets, water is circulated through the circulating cooling system to cool the interior of the concrete foundation 60. The flow regulating component is located at the inner end of the circulating cooling system. The flow regulating component automatically adjusts the cooling water flow rate according to the internal temperature of the concrete foundation 60, performing adaptive heat dissipation control. Water circulation begins 8 hours after pouring. During the heating period (0-48h), the internal temperature rise rate reaches 1.8℃ / h, and the inlet water temperature is adjusted to 18℃. During the peak period (48-72h), when the internal temperature rises and exceeds 50℃, the flow regulating component is automatically triggered and the water flow cross-section is increased, with the inlet and outlet water temperature difference controlled at 8℃. During the cooling period (after 72h), the inlet water temperature is gradually increased to 25℃, with a measured cooling rate of 1.6℃ / d, until the internal temperature of the concrete foundation 60 is below 50℃, at which point the flow regulating component automatically closes, reducing the cooling water flow cross-section. S4. Internal Stress Feedback: During the pouring process, a stress feedback component is pre-embedded. One end of the stress feedback component is inserted into the flow regulating component, and the other end is rigidly connected to the reinforcing cage. The stress feedback component is used to adaptively regulate the heat dissipation of the tensile stress inside the concrete foundation 60. When the temperature inside the concrete does not reach the 50℃ required for the flow regulating component to automatically activate, and a huge stress is generated inside the concrete foundation 60, the stress will directly act on the horizontal reinforcing bars of the reinforcing cage. The reinforcing bars will transfer the stress to the stress feedback component, which will force the flow regulating component to open, increase the flow cross-section of the cooling water, and accelerate the heat dissipation effect inside the concrete foundation 60.

[0021] S5. External Thermal Insulation and Moisture Retention: After the concrete has set, promptly cover the external regulating components and dynamically adjust the insulation layer thickness or spray cooling water according to changes in ambient temperature and concrete surface temperature. When the temperature difference between the external environment and the measured surface of the concrete foundation 60 is greater than 16℃, inflate the external regulating components, increasing the volume of the airbag 51 for insulation. When the temperature difference is less than 16℃, deflate the airbag 51. When the external temperature is greater than 30℃, spray water through the waterbag 50 every 1-2 hours; when the external temperature is between 15℃ and 30℃, spray water through the waterbag 50 every 3-4 hours; when the external temperature is less than 15℃, spray water through the waterbag 50 every 6-8 hours.

[0022] In step S3, the circulating cooling system includes a circulating water pipe 20, which is coiled inside the concrete foundation 60 and fixed above the reinforcing cage. The circulating water pipe 20 can be laid in multiple layers according to the actual thickness of the concrete foundation 60, with each layer spaced 60cm apart. One end of the circulating water pipe 20 is connected to an inlet pipe 22 through an installation pipe 21, and the other end of the circulating water pipe 20 is fixedly installed with an outlet pipe 23. The ends of the inlet pipe 22 and the outlet pipe 23 that are away from the circulating water pipe 20 are both located outside the concrete foundation 60. The outer end of the inlet pipe 22 is connected to an external water pipe. Cooling water enters the inlet pipe 22 through the external water pipe, flows in the circulating water pipe 20 and carries away the heat in the concrete foundation 60, and then flows out from the outlet pipe 23 and is collected.

[0023] like Figures 3-5 As shown, in one embodiment, the circulating water pipe 20 includes an inner pipe 201. One end of the inner pipe 201 is fixedly connected to and communicates with the installation pipe 21, and the other end is fixedly connected to and communicates with the outlet pipe 23. The diameters of the installation pipe 21 and the inlet pipe 22 are larger than the diameter of the inner pipe 201. Multiple outer pipes 202 and protruding pipes 203 are fixedly connected to the outer end of the inner pipe 201. The outer pipes 202 and protruding pipes 203 are arranged in a crisscross pattern. The outer pipes 202 are filled with a solid-liquid phase change material 204. The solid-liquid phase change material 204 absorbs heat and melts. When the heat of hydration of concrete... When the peak temperature arrives, the solid-liquid phase change material 204 first absorbs heat and melts, slowing down the rate at which the cooling water carries away the heat and preventing cold shock that could cause the concrete to crack. When the nighttime temperature drops sharply, the solid-liquid phase change material 204 solidifies and releases heat, preventing the concrete from cracking due to excessive temperature difference between the inside and outside. The heat-releasing solidification of the convex tube 203 increases the contact area with the concrete foundation 60. A water inlet valve 205 is fixedly installed on the side wall of the convex tube 203 near the water inlet pipe 22, and a one-way water outlet valve 206 is fixedly installed on the side wall of the convex tube 203 near the water outlet pipe 23.

[0024] The inlet valve 205 includes a cylinder and multiple support rods 2051 disposed at the inner end of the cylinder. A circular plate 2052 is fixedly installed between the support rods 2051. A sealing cover 2054 is installed on the upper end of the circular plate 2052 through a first telescopic rod 2053. A return spring 2055 is fixedly installed between the circular plate 2052 and the sealing cover 2054. The return spring 2055 is sleeved on the outer end of the first telescopic rod 2053. When the return spring 2055 is in a balanced state, the sealing cover 2054 covers one end of the cylinder and is located inside the convex tube 203. The sealing cover 2054 prevents the cooling water in the inner tube 201 from entering the convex tube 203.

[0025] like Figures 7-8 In some embodiments, the flow regulating component in step S3 includes an adjusting block 30, which is annular and fixed to the inner wall of the mounting pipe 21. The outer side wall of the adjusting block 30 has multiple circumferentially arranged water outlet holes 31. Cooling water enters the mounting pipe 21 and enters the inner pipe 201 through the water outlet holes 31. Multiple temperature conducting components are uniformly fixedly installed inside the adjusting block 30. A lifting cover 36 is installed on the upper end of the temperature conducting components through a second telescopic rod 34. An O-ring is provided at the movable part of the second telescopic rod 34 to seal it. A thermal spring 35 is installed inside the second telescopic rod 34. The thermal spring 35 is made of shape memory alloy. The thermal spring 35 elongates at a temperature of 50°C. When the temperature inside the concrete foundation 60 reaches or exceeds 50°C, the thermal spring 35 elongates due to heat, pushing the lifting cover 36 and the upper end of the adjusting block 30 to separate. Cooling water can pass through the inner ring of the adjusting block 30, so that the flow cross-sectional area of ​​the mounting pipe 21 increases with the increase of temperature. When the cross-sectional area of ​​the cooling water flow in the installation pipe 21 increases, the water pressure of the cooling water in the inner pipe 201 increases. The water pressure exerts a pushing force on the sealing cover 2054, and the applied pushing force is greater than the pulling force of the return spring 2055 on the sealing cover 2054, pushing the sealing cover 2054 away from the cylinder. The inlet valve 205 opens, and the cooling water enters the convex pipe 203. After flowing in the convex pipe 203, it is discharged into the inner pipe 201 through the one-way outlet valve 206, further and quickly removing the heat in the concrete foundation 60, rapidly cooling the interior of the concrete foundation 60, and preventing the concrete foundation 60 from cracking.

[0026] like Figures 7-8In some embodiments, the temperature-conducting component includes a fixing strip 33 made of heat-insulating material. The fixing strip 33 is fixed inside the adjusting block 30, and a heat-conducting block 332 is fixedly installed at one end. The heat-conducting block 332 is embedded in the outer end of the adjusting block 30 and fits against the inner wall of the mounting tube 21. The other end of the fixing strip 33 is located inside the inner ring of the adjusting block 30. A heat-conducting strip 331 is fixedly installed inside the fixing strip 33. One end of the heat-conducting strip 331 is fixedly connected to the heat-conducting block 332, and the other end is fixedly connected to the thermal spring 35. Both the heat-conducting block 332 and the heat-conducting strip 331 are made of heat-conducting metal. When the concrete foundation 60 heats up, it transfers the heat to the installation pipe 21. The installation pipe 21 then transfers the heat to the heat-conducting block 332 and the heat-conducting strip 331. The heat-conducting strip 331 then transfers the heat to the thermal spring 35. When the temperature inside the concrete foundation 60 reaches or exceeds 50°C, the thermal spring 35 extends and pushes the lifting cover 36 away from the adjusting block 30, increasing the flow cross-section of the cooling water. At the same time, the cooling water enters the inner pipe 201, increasing the water pressure inside the inner pipe 201. It also pushes open the inlet valve 205, allowing the cooling water to enter the convex pipe 203, quickly cooling the inside of the concrete foundation 60, eliminating temperature differences, and preventing cracking.

[0027] like Figure 8 and Figure 9 As shown, in some embodiments, a protective cover 32 is fixedly installed on the upper end of the adjusting block 30 by a column. The diameter of the protective cover 32 is larger than the diameter of the inner ring of the adjusting block 30. When the thermal spring 35 drives the lifting cover 36 to move upward, the lifting cover 36 is located inside the protective cover 32, so as to prevent the cooling water flow from acting directly on the outer end of the lifting cover 36.

[0028] like Figures 1-3 As shown, in one embodiment, the wire mesh 10 has two sides. When pouring concrete, the two layers of wire mesh 10 are laid on the upper and lower ends of the circulating water pipe 20 respectively. The setting of the wire mesh 10 further improves the crack resistance of the concrete foundation 60.

[0029] like Figures 12-15 As shown, in one embodiment, the stress feedback component in step S4 includes a sleeve 40, a rotating rod 41, and a push ring 42. Multiple sleeves 40 and rotating rods 41 are provided. One end of the sleeve 40 is inclined and fixed on the outer wall of the connection between the circulating water pipe 20 and the installation pipe 21, and penetrates the side wall of the circulating water pipe 20. The other end is sleeved on the fixed connection point of the steel cage of the rotating rod 41. The push ring 42 is located inside the inner ring of the adjusting block 30. The upper end of the push ring 42 is fixed to the lower end of the lifting cover 36 through the connecting column 43. When the push ring 42 moves upward, it can drive the lifting cover 36 to move upward. One end of the rotating rod 41 rotates within the adjusting block 30 via a torsion spring. One end of the rotating rod 41 is rotatably connected to a rotating shaft 401, which is fixed to the inner wall of the inner ring of the adjusting block 30. Both ends of the torsion spring are fixed to the outer wall of the rotating shaft 401 and the outer wall of the rotating rod 41. The rotating rod 41 rotates within the adjusting block 30 by compressing the torsion spring. The rotating rod 41 is connected to a ball head 46 via an adjusting assembly. The upper outer wall of the ball head 46 slides in contact with the lower outer wall of the push ring 42. The other end of the rotating rod 41 is inserted into the sleeve 40 and fixedly connected to the reinforcing cage. When the concrete foundation 60 heats up, even if the temperature does not reach 50°C, a huge tensile stress is generated inside the concrete foundation 60. This tensile stress will directly act on the reinforcing cage, causing the reinforcing bars to attempt to elongate. Because of the bond between the reinforcing steel and the surrounding concrete, the reinforcing steel will undergo slight tensile deformation. Even if the reinforcing steel only elongates by 0.2 mm, through the lever amplification effect of the rotating rod 41 (e.g., a lever arm ratio of 1:20), it can be converted into a displacement of 4 mm for the rotating rod 41, pushing the lifting cover 36 away from the adjusting block 30, increasing the flow cross-section of the cooling water. At the same time, the cooling water enters the inner pipe 201, increasing the water pressure in the inner pipe 201, and also pushes open the water inlet valve 205, allowing the cooling water to enter the convex pipe 203, quickly cooling the inside of the concrete foundation 60, eliminating temperature differences, and preventing cracking.

[0030] like Figure 15 As shown, in one embodiment, the adjusting assembly includes a fixed cylinder 44 fixed to the upper end of the rotating rod 41. A movable rod 45 is slidably connected inside the fixed cylinder 44. A bolt is threaded to the upper end of the fixed cylinder 44. By tightening the bolt, the inner end of the fixed cylinder 44 is brought into close contact with the side wall of the movable rod 45, thus fixing the movable rod 45 in place. The upper end of the movable rod 45 is fixedly connected to the lower end of the ball head 46, allowing adjustment of the distance between the ball head 46 and the push ring 42. This allows construction personnel to fine-tune the stress-lift cover 36 transmission coefficient on-site according to different concrete mix proportions and reinforcement ratios. For example, for high-strength concrete (brittle and prone to cracking), the sensitivity is increased; for low-grade concrete, the sensitivity is decreased.

[0031] like Figure 1 , Figure 10 and Figure 11As shown, in some embodiments, the external adjustment component in step S4 includes a water bladder 50. A water injection pipe 501 is fixedly installed on one side of the upper end of the water bladder 50, through which cooling water can be injected into the water bladder 50. An inflatable air bladder 51 is fixedly installed at the lower end of the water bladder 50. Multiple round pipes 53 are uniformly fixedly installed at the lower end of the air bladder 51. The inner ports of the round pipes 53 are connected to the interior of the water bladder 50 through connecting pipes 52. When it is necessary to spray water to cool the surface of the concrete foundation 60, water is injected into the water bladder 50, and air is injected at the same time. The gas inside the bladder 51 is discharged. Under the gravity of the water bladder 50 and the cooling water, the air bladder 51 adheres tightly to the surface of the concrete foundation 60. At the same time, the cooling water is evenly discharged to the surface of the concrete foundation 60 through the connecting pipe 52 and the round pipe 53. Because the air bladder 51 adheres tightly to the surface of the concrete foundation 60, it slows down the flow rate of the cooling water, allowing the concrete foundation 60 to maintain cooling water for a long time. Moreover, the temperature of the cooling water inside the water bladder 50 is transferred to the concrete foundation 60 through the air bladder 51, increasing the heat dissipation effect on the surface of the concrete foundation 60.

[0032] When the external ambient temperature is low at night and insulation of the concrete foundation surface 60 is required, the airbag 51 is inflated, and the airbag 51 expands (as shown in the image). Figure 11 As shown in the figure, the thickness of the airbag 51 is increased, and the air has a good heat insulation and heat preservation effect, so as to avoid the temperature difference between the inside and outside of the concrete foundation 60 being too large.

[0033] like Figure 11 As shown, in one embodiment, an anti-blocking plate 54 is fixedly installed at the bottom end of the circular tube 53, and multiple water outlets 55 are evenly opened on the bottom side wall of the circular tube 53 to prevent the lower end of the circular tube 53 from being blocked, so that cooling water can flow out from the water outlets 55.

[0034] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

[0035] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus.

Claims

1. A method for temperature-controlled and crack-prevention construction of large-volume concrete for wind turbine foundations in wind farms, characterized in that... include: The method specifically includes: wire mesh (10), circulating cooling system, flow regulating component, stress feedback component, and external adjustment component. Includes the following steps; S1. Construction preparation: Based on the dimensions of the large-volume concrete structure of the wind turbine foundation and the environmental conditions, conduct temperature field and stress field simulation calculations, determine the temperature control index and the layout scheme of the circulating cooling system, and lay the steel cage. S2. Concrete pouring: A layered continuous pouring process is adopted to control the thickness of each layer and the time interval between the upper and lower layers. S3, Internal water cooling: During the pouring process, steel wire mesh (10) and a circulating cooling system are simultaneously embedded, and after the concrete has initially set, water is circulated through the circulating cooling system to cool the inside of the concrete foundation (60). The flow regulating component is set at the inner end of the circulating cooling system. The flow regulating component automatically adjusts the cooling water flow rate according to the temperature inside the concrete foundation (60) to perform adaptive heat dissipation control. S4, Internal stress feedback: During the pouring process, a stress feedback component is pre-embedded. One end of the stress feedback component is inserted into the flow regulating component, and the other end is rigidly connected to the steel cage. The stress feedback component is used to adaptively regulate the heat dissipation of the tensile stress inside the concrete foundation (60). S5. External thermal insulation and moisture retention: After the concrete has set, cover the external adjustment components in a timely manner, and dynamically adjust the thickness of the insulation layer or spray cooling water according to changes in ambient temperature and concrete surface temperature.

2. The method for temperature-controlled crack prevention construction of large-volume concrete for wind turbine foundations in wind farms according to claim 1, characterized in that: The temperature control parameters mentioned in step S1 include: concrete pouring temperature ≤30℃, maximum internal temperature of concrete ≤70℃, temperature difference between inside and outside concrete ≤25℃, and concrete cooling rate ≤2℃ / d.

3. The method for temperature-controlled crack prevention construction of large-volume concrete for wind turbine foundations in wind farms according to claim 1, characterized in that: The circulating cooling system in step S3 includes a circulating water pipe (20), which is coiled inside the concrete foundation (60) and fixed above the steel cage. One end of the circulating water pipe (20) is connected to an inlet pipe (22) through an installation pipe (21), and the other end of the circulating water pipe (20) is fixedly installed with an outlet pipe (23). The ends of the inlet pipe (22) and the outlet pipe (23) away from the circulating water pipe (20) are both located outside the concrete foundation (60).

4. The method for temperature-controlled crack prevention construction of large-volume concrete for wind turbine foundations in wind farms according to claim 3, characterized in that: The circulating water pipe (20) includes an inner pipe (201). One end of the inner pipe (201) is fixedly connected to and communicates with the installation pipe (21), and the other end is fixedly connected to and communicates with the outlet pipe (23). Multiple outer pipes (202) and protruding pipes (203) are fixedly connected to the outer end of the inner pipe (201). The outer pipes (202) and protruding pipes (203) are arranged in a cross manner. The outer pipes (202) are filled with solid-liquid phase change material (204). An inlet valve (205) is fixedly installed on the side wall of the protruding pipe (203) near the inlet pipe (22). A one-way outlet valve (206) is fixedly installed on the side wall of the protruding pipe (203) near the outlet pipe (23).

5. The method for temperature-controlled crack prevention construction of large-volume concrete for wind turbine foundations in wind farms according to claim 4, characterized in that: The flow regulating component in step S3 includes an adjusting block (30), which is annular and fixed on the inner wall of the mounting pipe (21). The outer side wall of the adjusting block (30) is provided with a plurality of water outlet holes (31) arranged in a circle. A plurality of temperature conducting components are uniformly fixedly installed inside the adjusting block (30). A lifting cover (36) is installed on the upper end of the temperature conducting component through a second telescopic rod (34). A thermal spring (35) is installed inside the second telescopic rod (34). When the thermal spring (35) is heated and elongated, it pushes the lifting cover (36) and the upper end of the adjusting block (30) to separate, so that the flow cross-sectional area of ​​the mounting pipe (21) increases with the increase of temperature. When the cross-sectional area of ​​the cooling water flow in the installation pipe (21) increases, the water pressure of the cooling water in the inner pipe (201) increases, and the inlet valve (205) is opened. The cooling water enters the convex pipe (203), flows in the convex pipe (203), and is discharged into the inner pipe (201) through the one-way outlet valve (206).

6. The method for temperature-controlled crack prevention construction of large-volume concrete for wind turbine foundations in wind farms according to claim 5, characterized in that: The temperature-conducting component includes a fixing strip (33), which is made of heat-insulating material. The fixing strip (33) is fixed inside the adjusting block (30). A heat-conducting block (332) is fixedly installed at one end. The heat-conducting block (332) is embedded in the outer end of the adjusting block (30). The other end of the fixing strip (33) is located inside the inner ring of the adjusting block (30). A heat-conducting strip (331) is fixedly installed inside the fixing strip (33). One end of the heat-conducting strip (331) is fixedly connected to the heat-conducting block (332), and the other end is fixedly connected to the thermal spring (35).

7. The method for temperature-controlled crack prevention construction of large-volume concrete for wind turbine foundations in wind farms according to claim 1, characterized in that: The wire mesh (10) has two sides. When pouring concrete, the two layers of wire mesh (10) are laid on the upper and lower ends of the circulating water pipe (20).

8. The method for temperature-controlled crack prevention construction of large-volume concrete for wind turbine foundations in wind farms according to claim 1, characterized in that: The stress feedback component in step S4 includes a sleeve (40), a rotating rod (41), and a push ring (42). Multiple sleeves (40) and rotating rods (41) are provided. One end of the sleeve (40) is obliquely fixed on the outer wall of the connection between the circulating water pipe (20) and the installation pipe (21), and penetrates the side wall of the circulating water pipe (20). The push ring (42) is located inside the inner ring of the adjusting block (30), and the upper end of the push ring (42) is fixed to the lower end of the lifting cover (36) by the connecting column (43); One end of the rotating rod (41) rotates within the adjusting block (30) via a torsion spring and is connected to a ball head (46) via an adjusting assembly. The upper outer wall of the ball head (46) and the lower outer wall of the push ring (42) slide in contact. The other end of the rotating rod (41) is inserted into the sleeve (40) and fixedly connected to the reinforcing cage.

9. The method for temperature-controlled crack prevention construction of large-volume concrete for wind turbine foundations in wind farms according to claim 8, characterized in that: The adjustment assembly includes a fixed cylinder (44) fixed to the upper end of the rotating rod (41), and a movable rod (45) is slidably connected inside the fixed cylinder (44). The movable rod (45) is fixed by bolts, and the upper end of the movable rod (45) is fixedly connected to the lower end of the ball head (46).

10. The method for temperature-controlled crack prevention construction of large-volume concrete for wind turbine foundations in wind farms according to claim 1, characterized in that: The external adjustment component in step S4 includes a water bladder (50), an inflatable air bladder (51) is fixedly installed at the lower end of the water bladder (50), and a plurality of round tubes (53) are uniformly fixedly installed at the lower end of the air bladder (51). The inner port of the round tubes (53) is connected to the interior of the water bladder (50) through a connecting pipe (52).

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