Formwork embedded type dam face permanent heat preservation protection module and prefabrication and construction method

Abstract

The invention discloses a template embedded type dam face permanent heat preservation protection module and a prefabrication and construction method. Comprising a heat preservation core layer, a facing anti-seepage protection layer is arranged on the side, close to a concrete pouring formwork, of the heat preservation core layer, an internal pressure-bearing protection layer is arranged on the side, close to dam surface layer crack limiting steel bars, of the heat preservation core layer, and a thermal broken bridge supporting keel is arranged in the heat preservation core layer; an anchoring device is arranged in the area between the internal pressure-bearing protection layer and the dam surface layer crack limiting steel bars. The modular prefabrication and construction method is adopted, the prefabrication and installation method of a single module is simple and efficient, details such as anchoring protection measures are fully considered, the engineering construction operability is high, convenience and high efficiency are achieved, and the construction time of the heat preservation layer is greatly saved.

Description

Technical Field

[0001] The invention relates to the technical field of thermal insulation and protection of dam concrete in water conservancy projects, in particular to a template embedded permanent thermal insulation and protection module for dam surfaces and a prefabrication and construction method thereof. Background Art

[0002] When constructing concrete dams in extremely cold regions, the poured concrete needs to be insulated in a timely manner to prevent adverse factors such as cold waves, sudden drops in temperature, and large temperature differences between day and night from causing large fluctuations in the surface temperature of the dam concrete, reduce the temperature difference between the inside and outside of the concrete, and prevent the temperature stress caused by the large temperature difference from causing cracks in the dam.

[0003] Traditional insulation technology involves permanently insulating the concrete dam surface after the formwork is removed. For example, Chinese patent CN102505664B, a method for anti-aging dam concrete, first provides permanent insulation by covering it with polyethylene foam, insulation wool, adhesively bonded polystyrene boards, or spraying polyurethane rigid foam. The insulation layer is then covered with a layer of anti-aging paint, polyurea, or polymer mortar to protect it from extrusion, pulling, and impact caused by frozen reservoir water, aging and discoloration caused by solar radiation, and damage or fire caused by other construction operations. Alkali-resistant fiberglass mesh or wire mesh is laid in the middle of the protective layer for reinforcement, and anchored to the dam concrete using anchor bolts and other components. This provides permanent insulation and protection for the concrete dam surface.

[0004] Although the traditional permanent thermal insulation protection scheme for dam surface has played a certain protective role for dam concrete, it still has some deficiencies that need to be improved and optimized based on engineering practice experience and results. These deficiencies are mainly reflected in the following three aspects:

[0005] (1) There is a lag in thermal insulation protection and the dam concrete is at risk of cracking;

[0006] Traditional permanent insulation solutions rely on a clean dam surface after formwork removal. However, formwork removal cannot proceed until the newly poured concrete has initially set and its strength has reached the required level for removal. This results in a delay in dam insulation. Dam concrete, with its low early strength, is more susceptible to cracking due to thermal tensile stresses, necessitating timely permanent insulation.

[0007] (2) There are many on-site thermal insulation and protection procedures, which require high-altitude cross-operation and are difficult to construct;

[0008] Traditional dam insulation and protection systems are composed of a combination of various processes to address the adverse effects of large temperature differences, high water pressure, and reservoir water freezing. Each process involves multiple steps, making the process relatively complex. Furthermore, there are many restrictions during construction. For example, whether spraying polyurethane, polyurea, or anti-aging paint, the base surface must be kept clean and dry. Furthermore, insulation and protection construction overlap with pouring operations, significantly interfering with each other, making construction difficult and posing a high safety risk.

[0009] (3) The construction environment is complex, there are many interference factors, and the quality is difficult to control;

[0010] Traditional dam surface insulation and protection construction is significantly influenced by subjective factors, making quality difficult to control. Furthermore, strong winds often occur on site, and polyurethane materials are easily blown away and dispersed during spraying operations on the dam surface. This not only wastes materials and pollutes the environment, but also results in uneven spraying thickness and poor quality control. When applying the polymer mortar protective layer to the insulation layer, it is important to avoid water erosion. After initial setting, timely watering and curing are required to ensure the overall quality of the dam concrete insulation and protection system. Dam construction sites are complex, with numerous interfering factors, making quality control difficult.

[0011] It can be seen that the traditional thermal insulation protection scheme has a lag in the thermal insulation construction, which leads to the risk of cracking of the dam concrete; and the construction technology and procedures are complex, and are affected by many environmental interference factors, making construction difficult; most of the work requires high-altitude operations and cross-operations, and the risk factor is high. A new solution is needed to achieve better protection of the dam concrete.

[0012] In this context, some experts and scholars have proposed the idea of ​​a non-removal formwork. For example, in the field of construction, the Chinese patent CN202222438817.X - Thermal insulation structure integrated non-removal formwork installation system, proposes to use thermal insulation board core material and composite lightweight mortar protective layer to form a non-removal formwork, and fix the non-removal formwork to the outside of the inner membrane through screws, leaving a gap between the inner formwork and the thermal insulation formwork; then cast concrete in the gap; finally, remove the external limiting screws. This method is suitable for the exterior wall projects of civil construction projects, but is not suitable for large-volume concrete pouring such as water conservancy project dams. There is also a Chinese patent with application number CN202410402902.1, "A permanent intelligent thermal insulation formwork for concrete on the surface of a dam body and its production and construction method", which solves the problem that spraying or gluing thermal insulation materials cannot cover the dam concrete in time by sequentially arranging steel formwork, hydrophobic protective layer, transition layer and intelligent thermal insulation layer from the outside to the inside. This method focuses on using temperature sensors to monitor the surface temperature of the dam concrete, the internal temperature of the intelligent insulation layer, and the ambient temperature. It then controls a voltage regulator to output a certain voltage to both sides of the intelligent insulation layer, using conductive materials to convert electrical energy into thermal energy, thereby regulating the temperature of the intelligent insulation layer. However, no specific parameters or solutions are provided for this implementation. Similarly, Chinese invention CN 114892666 B, A Permanent Insulation Formwork Structure for Dam Concrete and Its Construction Method, proposes a structure comprising steel trusses, steel formwork, insulation formwork, and reinforcement bundles. During dam pouring, the steel trusses and steel formwork are first arranged, and then the insulation formwork is secured to the inside of the formwork using reinforcement bars. After concrete pouring is completed, the outer supporting structure, steel trusses and steel formwork, are removed.

[0013] Although the above patents have proposed some solutions for non-removal formwork, they are still in the preliminary conception stage. Specific issues regarding application in engineering need to be further studied, and a feasible, effective and complete technical system has not been formed. For example, the surface area of ​​the dam is large, so how to achieve seamless installation during layout; the thermal insulation performance of the thermal insulation material will be weakened after absorbing water, and no effective anti-seepage protection measures have been proposed; and thermal insulation materials such as polyurethane rigid foam are closed-cell structures. After compression and deformation, the closed-cell structure is destroyed, and the thermal insulation performance will be significantly reduced. The existing technology has defects in the protection of thermal insulation materials. The concrete pouring process of water conservancy project dams is complex, and the solutions described in the above patents have great limitations. There is no specific implementation plan for the materials, structure, size, layout and installation of the non-removal formwork, and it cannot adapt to the conditions and various needs of on-site construction. It is like a castle in the air and cannot be implemented in actual engineering for the time being. It is mainly reflected in the following aspects:

[0014] (1) The material of the inner and outer protective layers directly affects the weight of the non-disassembly formwork structure. In a field test of a non-disassembly formwork carried out on a certain project, in order to ensure the strength and overall aesthetics of the panel, the weight exceeded 2000kg. During installation, the formwork itself was too heavy, which not only made construction difficult and slow, but also faced the situation of being unable to install and stopping work. Finally, during the concrete pouring, the connecting fixing rods fell off and collapsed, posing a very serious safety hazard.

[0015] (2) The currently commonly used insulation materials with excellent thermal insulation performance have relatively low compressive strength compared to concrete. The height of a single-bin pouring layer of dam concrete is generally about 3m. When the concrete is put into the bin and vibrated, it will generate large lateral pressure and impact force of coarse aggregate. If there is no effective protection, it will be squeezed and deformed. Although the existing technology such as Chinese invention CN 114892666B - A permanent insulation template structure for dam concrete and its construction method has taken into account the protection problem of impact force, it offsets the impact force of coarse aggregate by arranging a protective layer in the inner layer of the insulation material. However, the lateral pressure is not considered enough. The lateral pressure of the concrete first acts on the protective layer, and then is directly transmitted to the insulation material in the middle through the protective layer, which will cause the insulation layer to be compressed and deformed.

[0016] (3) Insulation materials such as polyurethane rigid foam are mostly closed-cell structures. The cells generally contain low-boiling-point gases with a thermal conductivity lower than that of air. The comprehensive thermal conductivity is generally lower than that of air. Existing literature shows that at 50 kg / m 3 At this density, gas-phase thermal conductivity accounts for approximately 70% of the total thermal conductivity of polyurethane. If the insulation layer is deformed under pressure, the closed-cell structure will be destroyed, and its thermal insulation performance will be significantly reduced. Relevant experimental studies have shown that the reduction in thermal insulation performance is not linearly related to the thickness compression value. Existing technologies do not fully understand the weakening of thermal insulation performance after deformation of thermal insulation materials, and the corresponding protective measures are also inadequate. A large-scale project in the extremely cold northwest region of China attempted this ten years ago, but ultimately failed to achieve engineering application due to deformation and shedding of the insulation layer.

[0017] (4) All insulation materials have a certain degree of water absorption, and the thermal conductivity coefficient increases significantly after absorbing water, which greatly reduces the insulation effect. The non-disassembly formwork is made of prefabricated blocks of different sizes that are spliced ​​and installed in the warehouse. The joints become obvious leakage channels, and no effective structure or treatment method has been proposed in the existing technology. Secondly, the outer protective layer of the existing non-disassembly formwork design is relatively thin, and no effective anti-seepage measures have been proposed. It is easy to leak under the action of high head pressure, which will weaken the protective capacity of the dam's insulation layer.

[0018] In summary, traditional dam concrete thermal insulation technologies have shortcomings and need improvement. Existing solutions for removing formwork have significant structural limitations, leading to failure during the pilot phase. They offer only preliminary concepts and frameworks, but lack concrete, implementable parameters, technical indicators, and construction methods. These solutions fail to meet the requirements of dam concrete pouring and are therefore unsuitable for application in hydropower and water conservancy dam construction. Therefore, research into permanent thermal insulation and anti-seepage technologies suitable for hydropower dams is crucial. Summary of the Invention

[0019] The purpose of the present invention is to overcome the above-mentioned shortcomings and provide a template embedded permanent thermal insulation protection module for dam surface and its prefabrication and construction methods to solve the problems raised in the background technology.

[0020] In order to solve the above technical problems, the technical solution adopted by the present invention is: a template embedded permanent thermal insulation protection module for the dam surface, including a thermal insulation core layer, a decorative anti-seepage protection layer is provided on the side of the thermal insulation core layer close to the concrete pouring template, an internal pressure-bearing protection layer is provided on the side of the thermal insulation core layer close to the surface crack-limiting steel bars of the dam, a thermal-breaking bridge support keel is provided inside the thermal insulation core layer, and an anchoring device is provided in the area between the internal pressure-bearing protection layer and the surface crack-limiting steel bars of the dam.

[0021] Preferably, the surface anti-seepage protective layer is provided with a hydrophobic anti-icing coating, a cement-based anti-seepage coating and a matrix protective layer in sequence from the side in contact with the concrete casting formwork toward the inner side of the dam; the matrix protective layer includes a first fiber cement board and a first steel mesh arranged in the first fiber cement board.

[0022] Preferably, the internal pressure-bearing protective layer includes a second fiber cement board and a second steel mesh arranged in the second fiber cement board.

[0023] Preferably, the thermal bridge support keel includes a first anchor nut arranged in the decorative anti-seepage protective layer and a second anchor nut arranged in the internal pressure-bearing protective layer. The first anchor nut and the second anchor nut are threadedly matched with the two ends of the insulation screw, and the thread directions of the first anchor nut and the second anchor nut are opposite.

[0024] Preferably, a groove or step is provided on the side of the thermal insulation screw close to the first anchor nut, and an outer limiting flange is passed through the groove or step, which is in contact with the decorative anti-seepage protective layer; a groove or step is provided on the side of the thermal insulation screw close to the second anchor nut, and an inner limiting flange is passed through the groove or step, which is in contact with the internal pressure-bearing protective layer.

[0025] Preferably, the anchoring device includes an adjustable support rod provided between the internal pressure-bearing protective layer and the crack-limiting steel bars on the surface of the dam, and an anchor bar threadedly connected to the outer side of the second anchor nut.

[0026] Preferably, insertion holes for installing concrete casting formwork anchor bolts and concrete casting formwork support legs are provided in the concrete casting formwork, the surface anti-seepage protective layer, the thermal insulation core layer and the internal pressure-bearing protective layer. The concrete casting formwork anchor bolts are threadedly engaged with one end of the positioning cone, and the other end of the positioning cone is connected to the surface crack-limiting steel bars of the dam through a serpentine anchor bar; the concrete casting formwork support legs are fixedly connected to the concrete casting formwork bracket.

[0027] Preferably, one end of the thermal insulation core layer is higher than the end plane of the decorative anti-seepage protective layer and the internal pressure-bearing protective layer, forming a tenon structure; the other opposite end of the thermal insulation core layer is lower than the end plane of the decorative anti-seepage protective layer and the internal pressure-bearing protective layer, forming a tenon structure; each two adjacent template-embedded dam surface permanent thermal insulation protection modules are connected by the cooperation of the tenon structure and the tenon structure.

[0028] In addition, the present invention also discloses a prefabrication method of the above-mentioned template embedded dam surface permanent thermal insulation protection module, which comprises the following steps:

[0029] Step 1: Parameter determination;

[0030] Step 1.1: Determine the thickness of the insulation core layer based on the equivalent heat release coefficient of the insulation layer required by the dam design;

[0031]

[0032] Where: δ is the thickness of the insulation core layer, unit is m; γ is the thermal conductivity, unit is W / (m·K); β is the equivalent heat release coefficient, unit is W / m 2 K: k is the correction value: k is 1 to 1.2. When the adhesive joint is airtight, k is 1.2.

[0033] Step 1.2: Calculate the lateral pressure during dam concrete pouring, check this against the shear strength of the fiber cement board used for the facing anti-seepage protective layer and the internal pressure-bearing protective layer, and determine the thickness of the fiber cement board.

[0034] The flexural strength of 1cm fiber cement board is 12MPa. max ×10 -3 When <12, the thickness H of the fiber cement board is 1 cm;

[0035] When P max ×10 -3 When ≥12, the thickness H of the fiber cement board is calculated as follows:

[0036]

[0037] Where H: thickness of fiber cement board, unit: m; P max: Maximum lateral pressure of concrete, unit: kPa;

[0038] Step 1.3: Based on the thickness of the insulation core layer δ and the thickness of the fiber cement board H, calculate the total length of the insulation screw and the length of the thicker middle section as follows:

[0039]

[0040] L 中 =(δ-h Ⅰ -h Ⅱ );

[0041] Where: L is the length of the insulation screw, in m; δ is the thickness of the insulation core layer, in m; H Ⅰ H is the height of the first anchor nut, in m; Ⅱ is the height of the second anchor nut, in m; h Ⅰ is the thickness of the outer limiting flange, h Ⅱ is the thickness of the inner limit flange;

[0042] Step 1.4: Determine the size and weight of a single module;

[0043] Step 2: Manufacturing of surface anti-seepage protective layer;

[0044] Step 2.1: Mix XYPEX admixture, cement, fiber, and filler raw materials in a certain proportion and place them in a mixer to mix them thoroughly to form a uniform slurry.

[0045] Step 2.2: Pour the mixed slurry into the mold to half its height, then place the wire mesh into the slurry in the mold, keeping the wire mesh in the middle of the slurry; then secure the first anchor nuts to the wire mesh at the four corners of a square; finally, pour the mixed slurry into the mold to the thickness of the fiber cement board determined in step 1.2, and use a flattening machine and a pressing machine to flatten and press it, and then cure it to form;

[0046] Step 2.3: Cut and shape the fiber cement board according to the size determined in step 1.4, and reserve insertion holes for the concrete casting formwork anchor bolts and concrete casting formwork support legs at corresponding positions to obtain the base protective layer;

[0047] Step 2.4: Apply a layer of XYPEX anti-seepage material on the smooth surface of the base protective layer to obtain a cement-based anti-seepage coating;

[0048] Step 2.5: Apply a layer of hydrophobic coating on the surface of the cement-based anti-seepage coating to obtain a hydrophobic anti-icing coating;

[0049] Step 3: Manufacturing of internal pressure-bearing protective layer:

[0050] Step 3.1: Mix XYPEX admixture, cement, fiber, and filler raw materials in a certain proportion and place them in a mixer to mix them thoroughly to form a uniform slurry.

[0051] Step 3.2: Pour the mixed slurry into the mold to half its height, then place the wire mesh into the slurry in the mold, keeping it in the middle of the slurry. Arrange the second anchor nuts in a square pattern on the wire mesh at the four corners, with the positions corresponding to the first anchor nuts. Finally, pour the mixed slurry into the mold to the fiber cement board thickness determined in step 1.2, and use a flattening machine and a press to flatten and press it, and then cure it to form.

[0052] Step 3.3: Determine the dimensions according to step 1.4, cut and shape the fiber cement board, and reserve insertion holes for the concrete casting formwork anchor bolts and concrete casting formwork support legs at the corresponding positions to obtain the internal pressure-bearing protective layer;

[0053] Step 4: pouring and extruding the insulation core layer;

[0054] Step 4.1: Insert the two limiting flanges into the two ends of the insulation screw respectively;

[0055] Step 4.2: Place the rough surface of the facing anti-seepage protective layer and the rough surface of the internal pressure-bearing protective layer parallel to each other. Screw the threaded sections of multiple insulation screws into the first anchor nut and the second anchor nut, respectively, to connect the facing anti-seepage protective layer and the internal pressure-bearing protective layer to form a whole. Then, use a template to seal all four sides, leaving only one pouring port, to form a six-sided sealed casting mold.

[0056] Step 4.3: Using a one-step casting and extrusion molding process, the interior of the mold is densely filled with polyurethane rigid foam insulation material; after the shape is finalized, the surrounding templates are removed;

[0057] Step 4.4: Use tools to drill through the reserved holes for the concrete pouring formwork anchor bolts and concrete pouring formwork support legs on the facing anti-seepage protective layer and the internal pressure-bearing protective layer, and drill through the insulation core layer;

[0058] Step 4.5: Cut and trim the four sides, and form a mortise and tenon structure according to the principle of upper and lower correspondence and left and right correspondence, so as to form a seamless connection when multiple modules are spliced ​​and installed.

[0059] The present invention also discloses a construction method of the template embedded dam surface permanent thermal insulation protection module, which is characterized in that it comprises the following steps:

[0060] Step 1: Transportation and hoisting;

[0061] According to the dam concrete pouring schedule, the prefabricated template embedded dam surface permanent insulation protection modules are transported in batches to the construction site warehouse. Then, based on the daily concrete storage area, these modules are hoisted and transported to the storage surface via a cable crane.

[0062] Step 2: Template embedded splicing installation:

[0063] Step 2.1: After the concrete casting formwork is erected, the module's surface anti-seepage protective layer is placed close to the casting formwork, and a balancing cushion is laid between the inside of the concrete casting formwork and the outer surface of the module. This cushion acts as a buffer for the module's surface protective layer during concrete pouring, preventing it from cracking under pressure. It also prevents the release agent and oil stains on the concrete casting formwork from contaminating the surface anti-seepage protective layer and preventing the two from sticking together when the formwork is removed. During arrangement, the concrete casting formwork anchor bolts and concrete casting formwork support legs are passed through the reserved insertion holes into the bin, and the concrete casting formwork anchor bolts are threaded into one end of the positioning cone. At this time, the other end of the positioning cone is connected to the dam surface crack-limiting steel bars via serpentine anchor bars.

[0064] Step 2.2: Install adjacent modules in accordance with the principle of corresponding mortise and tenon joints. Before joining, apply adhesive evenly to the surface of the tenon joints, then insert the tenons into the corresponding mortise grooves to ensure seamless connection between adjacent modules.

[0065] Step 2.3: Adjust the length of the adjustable support rods according to the actual distance between the assembled modules and the dam surface crack-limiting steel bars, and secure them in place to prevent the modules from shifting or falling into the silo due to the concrete pouring and vibration.

[0066] Step 2.4: Screw the threaded ends of multiple anchor bars into the second anchor nut of the internal pressure-bearing protective layer, with the other ends facing into the silo. After the concrete is poured, the anchor bars and the dam body form a whole, thereby firmly fixing the template-embedded permanent insulation protection module.

[0067] Step 2.5: Use edge protection covers to temporarily seal the top surface of the uppermost module. This prevents the concrete slurry from contaminating the module's mortise and tenon joints during pouring and prevents damage to the insulation core during flushing.

[0068] Step 3: Inspection and sealing;

[0069] Step 3.1: When removing the concrete pouring formwork after concrete pouring, first unscrew the concrete pouring formwork anchor bolts connected to the positioning cone on the outside, and lift the concrete pouring formwork upward along the module surface; after the upper formwork support and panel are installed, remove the concrete pouring formwork support legs of the lowest formwork support from the insertion holes, finally exposing the surface anti-seepage protective layer of the silo concrete dam surface;

[0070] Step 3.2: Use the tool to hang on the bracket of the upper formwork, and people go down to the dam surface along the tool to inspect and seal;

[0071] Step 3.3: After the formwork of the next warehouse is erected, remove the protective cover on the top of the installed module, and install the new module on the top of the installed module according to the mortise and tenon structure. Then repeat the above steps. When the dam is poured, the permanent insulation protection module embedded in the formwork of the entire dam surface is also arranged, realizing the protection of the dam concrete throughout its life cycle.

[0072] Beneficial effects of the present invention:

[0073] 1. The structure of the present invention is scientific and reasonable, and fully considers the lateral pressure and coarse aggregate impact force when the concrete is vibrated into the silo. The load is evenly transferred from the internal pressure-bearing protective layer to the decorative anti-seepage protective layer through the thermal bridge support keel, and then transmitted from the decorative anti-seepage protective layer to the outer casting formwork. The internal thermal insulation core layer will not be squeezed and deformed.

[0074] 2. The present invention can calculate the size, thickness and other parameters of a single module according to the actual engineering situation, which not only meets the load bearing capacity requirements but also takes into account the structure and characteristics of the dam casting template, and has good engineering adaptability.

[0075] 3. The present invention can avoid the joints that exist during modular construction through the mortise and tenon structure, and can realize modular seamless splicing installation, so that the dam's thermal insulation and anti-seepage protection layer becomes a whole, preventing the joints from becoming weak links in thermal insulation protection, and providing better thermal insulation and anti-seepage performance, thereby providing better protection for the dam.

[0076] 4. This system adopts modular prefabrication and construction methods. The prefabrication and installation methods of a single module are simple and efficient, and full consideration is given to details such as anchoring protection measures. The construction is highly operable, convenient and efficient, which greatly saves the construction time of the insulation layer.

[0077] 5. The present invention has many functions. In addition to the main thermal insulation function, by adding cement-based admixtures to the surface anti-seepage protective layer, arranging an anti-seepage coating on the surface, and adding a hydrophobic anti-icing layer in the water level change area, the system has an integrated structure and function of thermal insulation and anti-seepage protection.

[0078] 6. The template-embedded permanent thermal insulation protection module of the present invention has an internal pressure-bearing protective layer with high structural strength and good flexural resistance. It can withstand the lateral pressure generated by the silo and vibration during the pouring of dam concrete, as well as the impact force of coarse aggregate in the four-graded concrete, to prevent damage to the system.

[0079] 7. The present invention proposes a thermally broken bridge support keel structure that can evenly transfer the concrete load from the inner protective layer through the thermally broken bridge support keel structure to the outer protective layer during pouring, and further to the concrete pouring formwork. This prevents extrusion deformation of the central insulation core layer and avoids the weakening of the insulation performance caused by compression deformation of the insulation core layer. Similarly, after the dam is completed and put into operation, it can reversely transfer the high head pressure of the reservoir area to the dam concrete, providing excellent protection for the insulation core layer.

[0080] 8. Compared with the existing non-removal formwork technology, the materials and structures used in the present invention will not penetrate to the outer surface, and can form a good thermal bridge between the dam concrete and the external environment, reducing the adverse effects of ambient temperature on the temperature of the dam concrete.

[0081] 9. The modular prefabrication and installation technical solution proposed in the present invention can not only shift the workload of dam thermal insulation protection forward and complete the module prefabrication work in the factory; it is also light in weight, modular in installation, and convenient and efficient in construction. It can well adapt to the dam concrete pouring construction and realize the synchronization of permanent insulation and dam concrete pouring.

[0082] 10. This invention prefabricates modules in a factory, eliminating the complex construction environment associated with on-site operations, resulting in better quality control and lower costs. It also avoids high-altitude cross-operation, providing a high safety factor and significantly reducing the workload of thermal insulation and protection, promoting technological innovation and delivering significant economic and social benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0083] Figure 1 This is a structural diagram of a template-embedded permanent thermal insulation protection module for dam surfaces;

[0084] Figure 2 for Figure 1 A schematic diagram of the enlarged structure of the middle surface anti-seepage protective layer;

[0085] Figure 3 for Figure 1 A schematic diagram of the enlarged structure of the internal pressure-bearing protective layer;

[0086] Figure 4 for Figure 1 A schematic diagram of the enlarged structure of the medium-heat thermal bridge support keel;

[0087] Figure 5 This is a structural diagram of the connection between the concrete pouring formwork, the concrete pouring formwork support, and the formwork-embedded dam surface permanent thermal insulation protection module;

[0088] Figure 6 This is a schematic diagram of the upper and lower layers of embedded dam surface permanent insulation protection modules connected to each other through tenon and mortise structures. DETAILED DESCRIPTION

[0089] The present invention will be described in further detail below with reference to the accompanying drawings and specific embodiments.

[0090] Example 1:

[0091] like Figure 1-6 As shown: A template embedded permanent thermal insulation protection module for the dam surface, including a thermal insulation core layer 4, a decorative anti-seepage protection layer 1 is provided on the side of the thermal insulation core layer 4 close to the concrete pouring template 6, an internal pressure-bearing protection layer 2 is provided on the side of the thermal insulation core layer 4 close to the dam surface crack-limiting steel bars 7, a thermal-breaking bridge support keel 3 is provided inside the thermal insulation core layer 4, and an anchoring device 5 is provided in the area between the internal pressure-bearing protection layer 2 and the dam surface crack-limiting steel bars 7.

[0092] Preferably, the surface anti-seepage protective layer 1 is provided with a hydrophobic anti-icing coating 1.1, a cement-based anti-seepage coating 1.2 and a base protective layer 1.3 in sequence from the side in contact with the concrete casting formwork 6 toward the inner side of the dam; the base protective layer 1.3 includes a first fiber cement board 1.3.1 and a first steel wire mesh 1.3.2 arranged in the first fiber cement board 1.3.1.

[0093] In this embodiment, the base protective layer is a fiber cement board pressed from raw materials such as fiber and cement, with a thickness ranging from 10 to 50 mm. The thickness of the base protective layer in the decorative anti-seepage protective layer is the same as the thickness of the internal pressure-bearing protective layer, which is calculated based on the lateral pressure of the concrete.

[0094] During pressing, XYPEX admixture is added to the slurry at a ratio of 1% to 3% of the cement dosage, which can achieve a good anti-seepage effect.

[0095] Preferably, one or more layers of steel mesh are arranged inside the substrate protective layer, the mesh opening of the steel mesh is 2 to 4 cm, and the wire diameter of the steel mesh is 0.8 to 1.5 mm.

[0096] Inside the base protective layer, multiple first anchor nuts are arranged at intervals of 500mm. The nuts are made of stainless steel, carbon steel or nylon. The inner diameter of the first anchor nut is 10mm, and the height is 1 / 2 of the thickness of the fiber cement board. One side of the first anchor nut is flush with the inner surface of the base protective layer, and the other side is located in the center of the fiber cement layer, pressing the wire mesh. First, the force borne by the first anchor nut is transmitted more evenly to the fiber cement board to prevent damage caused by excessive local stress; second, the height of the first anchor nut is only half of the fiber cement board, and the outer surface of the base protective layer is not damaged, maintaining its beauty and overall protective performance; third, there are no protrusions on the inner surface, which facilitates the batch stacking and transportation of prefabricated modules and reduces transportation costs.

[0097] The base protective layer has a rough, hairy surface on one side and a smooth surface on the other. The smooth surface faces outward, enhancing the smoothness and aesthetics of the dam's surface while also reducing ice buildup and the pull force of ice on the base protective layer. The rough, hairy surface faces inward, improving adhesion to the insulation core and enhancing the durability of the overall structure.

[0098] The outer surface of the base protective layer is coated with a cement-based anti-seepage coating made of XYPEX concentrate. The thickness of the coating is 1 to 2 mm. This further enhances its anti-seepage capability and prevents high head pressure from penetrating through the base protective layer and entering the insulation core layer when used on the upstream side of the dam, thereby weakening its thermal insulation performance.

[0099] To protect against pull-out damage caused by freezing reservoir water in severely cold regions, the exterior of the anti-seepage layer is coated with a hydrophobic coating made of an organic fluorocarbon resin or silicone oligomer, with a thickness of 0.1 to 0.5 mm. The hydrophobic coating forms a protective film on the surface of the base protective layer, preventing water penetration and protecting it from damage caused by reservoir water. This prevents and reduces surface ice formation and improves its freeze-thaw resistance.

[0100] Preferably, the internal pressure-bearing protective layer 2 includes a second fiber cement board 2.1 and a second steel mesh 2.2 arranged in the second fiber cement board 2.1.

[0101] The main function of the internal pressure-bearing protective layer is to protect the thermal insulation core layer to prevent it from being damaged by the lateral extrusion force during concrete entry and vibration and the impact force of aggregates. This requires that the base protective layer itself has good flexural strength and impact resistance.

[0102] The internal pressure-bearing protective layer is a fiber cement board made by pressing raw materials such as fiber and cement. During the pressing process, XYPEX admixture is added to the slurry. The adding ratio is 1% to 3% of the cement dosage, which can achieve a good anti-seepage effect.

[0103] The thickness of the fiber cement board determines its flexural strength and impact resistance, and must be greater than the lateral pressure during dam concrete pouring. The thickness of the fiber cement board ranges from 20 to 50 mm, and the specific thickness is determined by calculation.

[0104] According to the ACI 347-04 Guide to Concrete Casting Formwork, when the slump value of concrete is ≤175mm, and the placement height under normal vibration is ≤4.2m, and the placement rate is <21.m / h, the lateral pressure of concrete is calculated according to the following formula.

[0105]

[0106] Among them, P max : Maximum lateral pressure of concrete, unit kPa; C w : Unit weight coefficient, w: concrete density, unit: kg / m 3 ; C c : chemical coefficient, value is 1.2; R: concrete pouring rate, unit is m / h; T: concrete temperature during placement, unit is ℃; and after testing, the performance indicators of 10mm thick fiber cement board are as follows:

[0107] Table 1 10mm fiber cement board related technical parameters

[0108]

[0109] As shown in Table 1, the flexural strength of the 10 mm fiber cement board is 12 MPa.

[0110] Working condition 1: When P max ×10 -3 When <12, the thickness H of the fiber cement board is 10 mm;

[0111] Working condition 2: When P max ×10 -3 When ≥12, the thickness H of the fiber cement board is calculated according to the following formula:

[0112]

[0113] Where H: thickness of fiber cement board, unit: m; P max : Maximum lateral pressure of concrete, unit: kPa.

[0114] One or more layers of steel mesh are arranged inside the internal pressure-bearing protective layer. The mesh opening of the steel mesh is 2 to 4 cm, and the wire diameter of the steel mesh is 0.8 to 1.5 mm.

[0115] A plurality of second anchor nuts are arranged inside the internal pressure-bearing protective layer at intervals of 500 mm, and the positions and quantities of the second anchor nuts correspond one-to-one to the first anchor nuts in the finishing anti-seepage protective layer.

[0116] The second anchor nut is made of stainless steel, carbon steel, or nylon. Its inner diameter is 10 mm, and its height is the same as the thickness of the fiber cement board. It is placed across the internal pressure-bearing protective layer, with one side flush with the inner surface of the layer and the other side flush with the outer surface. There are no protrusions on either side, facilitating bulk stacking and transportation of prefabricated modules.

[0117] Both sides of the fiber cement board have rough surfaces, which not only facilitates good bonding with the polyurethane material of the insulation core layer, but also allows the extrusion and impact forces generated during concrete pouring and vibration to be evenly distributed, making the overall pressure-bearing capacity of the insulation protection system more uniform, thereby increasing its compressive resistance and durability.

[0118] Preferably, the thermal bridge support keel 3 includes a first anchor nut 3.1 arranged in the decorative anti-seepage protective layer 1 and a second anchor nut 3.2 arranged in the internal pressure-bearing protective layer 2. The first anchor nut 3.1 and the second anchor nut 3.2 are threadedly matched with the two ends of the insulation screw 3.3, and the thread directions of the first anchor nut 3.1 and the second anchor nut 3.2 are opposite.

[0119] Preferably, a groove or step is provided on the side of the thermal insulation screw 3.3 close to the first anchor nut 3.1, and an outer limiting flange 3.4 in contact with the decorative anti-seepage protective layer 1 is passed through the groove or step; a groove or step is provided on the side of the thermal insulation screw 3.3 close to the second anchor nut 3.2, and an inner limiting flange 3.5 in contact with the internal pressure-bearing protective layer 2 is passed through the groove or step.

[0120] The insulation screw features a double-threaded structure with thin ends and a thick center. The diameters are 10mm at each end and 20mm in the center. The offset created by this diameter change is used to clamp the limiting flange to the surface of the surface's anti-seepage protective layer and the internal pressure-bearing protective layer, increasing the load-bearing area and preventing localized damage.

[0121] The material is nylon or basalt fiber composite reinforcement, which has the advantages of high strength, good thermal insulation and strong corrosion resistance, forming a thermal bridge structure to prevent the external environment temperature changes from being transmitted to the interior of the concrete through the screw.

[0122] The limiting flange is an iron or steel O-shaped gasket with an inner diameter of 10mm, an outer diameter of 100mm, and a thickness of 5mm. The limiting flange prevents the insulation core from being compressed and deformed by the pressure. Furthermore, the gasket's diameter is significantly larger than that of the insulation screw, increasing the load-bearing area and preventing localized pressure damage to the inner and outer fiber cement boards.

[0123] First, insert the two ends of multiple insulation screws into the limiting flanges, and then screw them into the nuts of the surface anti-seepage protective layer and the internal pressure-bearing protective layer respectively, serving as a supporting skeleton to connect the inner and outer layers to form a whole.

[0124] The length of the insulation screw is obtained by calculation: according to the thickness of the insulation core layer δ and the thickness of the fiber cement board H, the total length of the insulation screw and the length of the thicker middle section are calculated according to the following formula.

[0125]

[0126] L 中=(δ-h Ⅰ -h Ⅱ );

[0127] Where: L is the length of the insulation screw, in m; δ is the thickness of the insulation core layer, in m; H Ⅰ H is the height of the first anchor nut, in m; Ⅱ is the height of the second anchor nut, in m; h Ⅰ is the thickness of the outer limiting flange, h Ⅱ is the thickness of the inner limiting flange, h Ⅰ =h Ⅱ =0.005m.

[0128] During concrete pouring, the lateral extrusion and impact forces generated by vibration first act on the internal pressure-bearing protective layer. When the insulation core layer is subjected to a large load and may experience compression deformation, the limiting flange close to the internal pressure-bearing protective layer begins to bear force, first transferring the load of the internal pressure-bearing protective layer to the insulation screw. This load is then transferred through the insulation screw to the limiting flange close to the outer decorative anti-seepage protective layer. Finally, the limiting flange evenly transfers the load to the decorative anti-seepage protective layer. The thermal bridge supports the keel structure, effectively protecting the central insulation core layer.

[0129] Preferably, the anchoring device 5 comprises an adjustable support rod 5.1 provided between the internal pressure-bearing protective layer 2 and the dam surface crack-limiting steel bar 7 and an anchor bar 5.2 threadedly connected to the outer side of the second anchor nut 3.2.

[0130] The adjustable support rod is used to temporarily fix the permanent thermal insulation and anti-seepage protection module of the dam surface arranged against the inner side of the concrete casting formwork. One end is supported on the internal pressure-bearing protective layer of the module, and the other end is supported on the concrete base surface or crack-limiting steel bars in the bin. Adjusting the length of the adjustable support rod keeps the module close to the formwork to prevent it from shifting or overturning due to the entry of concrete and vibration. When the concrete in the bin is poured to a certain height, the module is pressed against the formwork by the side pressure of the concrete itself, and the adjustable support rod is retracted to fix the next layer of modules. In this embodiment, the adjustable support rod can adopt a spring-clip telescopic rod. After each length adjustment, the length is locked by the cooperation of the spring clip and the corresponding hole.

[0131] The anchor bar is a serpentine structure with a thread at one end. The thread diameter matches the second anchor nut. The anchor bar length ranges from 15cm to 50cm. It can be made of high-strength materials such as steel, iron, nylon, and basalt fiber.

[0132] Once the permanent thermal insulation and anti-seepage protection module is installed and secured, the threaded end of the anchor bar is screwed into the second anchor nut, with the serpentine end facing inward. When concrete is poured in the silo to the height of the anchor bar, the serpentine anchor bar is completely encased in concrete. Once the concrete solidifies, the serpentine anchor bar securely fastens the permanent thermal insulation and anti-seepage protection module to the dam surface.

[0133] Preferably, the concrete casting formwork 6, the surface anti-seepage protective layer 1, the thermal insulation core layer 4, and the internal pressure-bearing protective layer 2 are provided with insertion holes for installing the concrete casting formwork anchor bolts 8 and concrete casting formwork support legs 9. The concrete casting formwork anchor bolts 8 are threadedly engaged with one end of a positioning cone 10, the other end of which is connected to the dam surface crack-limiting steel bars 7 via a serpentine anchor bar 11. The concrete casting formwork support legs 9 are fixedly connected to the concrete casting formwork brackets 12. Currently, the formwork for dam concrete casting must be secured using anchor bolts, positioning cones, and anchor bars. The concrete casting formwork support legs 9 and the concrete casting formwork brackets 12 can bear the weight of the entire formwork and the module, and the concrete casting formwork anchor bolts 8 can fix the module and the formwork together, play a certain supporting role, and prevent the module from tipping into the warehouse. In order to make the formwork embedded dam surface permanent insulation protection module better adapt to the dam concrete pouring, according to the structural characteristics of the construction steel formwork, concrete casting formwork anchor bolt insertion holes and concrete casting formwork support leg insertion holes are reserved in each module, and their size and quantity are determined according to the structure of the external formwork.

[0134] Preferably, if Figure 6 As shown, one end of the thermal insulation core layer 4 is higher than the end planes of the finishing anti-seepage protective layer 1 and the internal pressure-bearing protective layer 2, forming a tenon structure; the other opposite end of the thermal insulation core layer 4 is lower than the end planes of the finishing anti-seepage protective layer 1 and the internal pressure-bearing protective layer 2, forming a tenon structure; each two adjacent template-embedded dam surface permanent thermal insulation protection modules are connected by the cooperation of the tenon structure and the tenon structure.

[0135] In this embodiment, the insulation core layer is made of polyurethane rigid foam insulation material, styrene board material, or polyethylene foam material, and is formed by a one-step casting and extrusion molding process. The thickness of the insulation core layer is determined according to the dam design requirements and can be between 3 and 15 cm.

[0136] Determine the thickness of the insulation core layer based on the equivalent heat release coefficient of the insulation layer required by the dam design;

[0137]

[0138] Where: δ is the thickness of the insulation core layer, unit is m; γ is the thermal conductivity, unit is W / (m·K); β is the equivalent heat release coefficient, unit is W / m 2K: k is the correction value: k ranges from 1 to 1.2. When the adhesive joint is airtight, k is set to 1.2.

[0139] According to the equivalent heat release coefficient required by the dam design, the thickness δ of the insulation core layer can be calculated using the above formula.

[0140] The thermal insulation core layer, the surface anti-seepage protective layer and the internal pressure-bearing protective layer form an integral whole, and a mortise and tenon structure is formed around the perimeter, with the groove depth and tenon length both being 5cm.

[0141] When carrying out modular splicing and installation on site, first use foam glue, structural glue and other adhesives to apply on the surface of the tenon and mortise, and then splice the tenons and mortise of adjacent modules one by one to achieve seamless connection of multiple modules and prevent environmental temperature fluctuations from having an adverse effect on the dam concrete through the joints.

[0142] Preferably, the top surface of the topmost thermal insulation core layer 4, the surface anti-seepage protective layer 1 and the internal pressure-bearing protective layer 2 is also provided with an edge sealing protective cover 13. The edge sealing protective cover 13 is used to temporarily seal the top surface of the topmost module to prevent the concrete slurry from contaminating the mortise and tenon structure of the module during pouring, and to prevent damage to the thermal insulation core layer during flushing. The groove structure of the edge sealing protective cover corresponds to the tenon of the module. After all the modules of the warehouse are spliced, installed and fixed, the edge sealing protective cover is used to cover the tenon of the module. This not only prevents the concrete slurry from contaminating the mortise and tenon structure of the module during pouring, but also prevents damage to the thermal insulation core layer during flushing. It is removed when the permanent thermal insulation and anti-seepage protection module of the dam surface of the next warehouse is spliced ​​and installed.

[0143] Example 2: A method for prefabricating a template-embedded permanent thermal insulation protection module for a dam surface, comprising the following steps:

[0144] Step 1: Parameter determination;

[0145] Step 1.1: Determine the thickness of the insulation core layer based on the equivalent heat release coefficient of the insulation layer required by the dam design;

[0146]

[0147] Where: δ is the thickness of the insulation core layer, unit is m; γ is the thermal conductivity, unit is W / (m·K); β is the equivalent heat release coefficient, unit is W / m 2 K: k is the correction value: k is 1 to 1.2. When the adhesive joint is airtight, k is 1.2.

[0148] Step 1.2: Calculate the lateral pressure during dam concrete pouring, check this against the shear strength of the fiber cement board used for the facing anti-seepage protective layer and the internal pressure-bearing protective layer, and determine the thickness of the fiber cement board.

[0149] According to the ACI 347-04 Guide to Concrete Formwork, when the concrete slump value is ≤175mm, and the placement height under normal vibration is ≤4.2m, and the placement rate is <21.m / h, the lateral pressure of the concrete is calculated as follows:

[0150]

[0151] Where P max : Maximum lateral pressure of concrete, unit kPa; C w : Unit weight coefficient, w: concrete density, unit: kg / m 3 ; C c : chemical coefficient, value is 1.2; R: concrete pouring rate, unit is m / h; T: concrete temperature during placement, unit is ℃;

[0152] The flexural strength of 1cm fiber cement board is 12MPa. max ×10 -3 When <12, the thickness H of the fiber cement board is 1 cm;

[0153] When P max ×10 -3 When ≥12, the thickness H of the fiber cement board is calculated as follows:

[0154]

[0155] Where H: thickness of fiber cement board, unit: m; P max : Maximum lateral pressure of concrete, unit kPa; Step 1.3: Based on the thickness of the insulation core layer δ and the thickness of the fiber cement board H, calculate the total length of the insulation screw and the length of the thicker middle section according to the following formula.

[0156]

[0157] L 中 =(δ-h Ⅰ -h Ⅱ );

[0158] Where: L is the length of the insulation screw, in m; δ is the thickness of the insulation core layer, in m; H Ⅰ H is the height of the first anchor nut, in m; Ⅱ is the height of the second anchor nut, in m; h Ⅰ is the thickness of the outer limiting flange, h Ⅱ is the thickness of the inner limiting flange, h Ⅰ =h Ⅱ =0.005m.

[0159] Step 1.4: Determine the size and weight of a single module.

[0160] 80% of the formwork used for concrete pouring in water conservancy dams is large, standard-sized steel formwork, such as Doka formwork. For this, modular design and calculations are based on the structural characteristics of the large formwork (size, size and number of positioning cones, position and length of support legs, etc.), and the principle of evenly dividing the individual formwork blocks. Each module is controlled to be a square or rectangular with a side length of 1000mm to 3000mm, and a weight of 50 to 500kg. The dimensions of the individual insulation and anti-seepage protection modules, the size and number of reserved positioning cone holes, and the size and location of the reserved formwork support leg insertion holes are determined to match the large formwork, enabling large-scale installation at the construction site.

[0161] For the remaining small and special-shaped templates, they are categorized by size, location, and quantity. For large quantities of uniformly sized components, the modules are designed and produced exactly according to the small templates and then transported to the site for installation. For smaller quantities and varying sizes, standardized modules are cut on-site using tools such as cutting machines and then installed and secured inside the special-shaped templates.

[0162] Step 2: Fabrication of surface anti-seepage protective layer

[0163] Step 2.1: Mix XYPEX admixture, cement, fiber, filler and other raw materials in a certain proportion and send them into a mixer for stirring to ensure that all raw materials are fully mixed to form a uniform slurry.

[0164] Step 2.2: Pour the mixed slurry into the mold to half the height, then place the wire mesh into the slurry in the mold, keeping the wire mesh in the middle of the slurry; then fix the first anchor nut on the wire mesh at the four corners of a square, and ensure that the spacing between adjacent bolts is 500mm; finally, pour the mixed slurry into the mold to the standard height (the thickness of the fiber cement board determined in step 1.2), and use a 7000-ton flattening machine and a pressing machine to flatten and press it, and then maintain the shape.

[0165] Step 2.3: Determine the size according to step 1.4, cut and shape the fiber cement board, and reserve insertion holes for the concrete casting formwork anchor bolts and concrete casting formwork support legs at corresponding positions to obtain the base protective layer.

[0166] Step 2.4: Apply 1-2 mm of XYPEX anti-seepage material on the smooth surface of the base protective layer to obtain a cement-based anti-seepage coating.

[0167] Step 2.5: Apply a layer of hydrophobic coating on the surface of the anti-seepage coating. The material of the hydrophobic coating is organic fluorocarbon resin or organic silicon oligomer. The thickness of the hydrophobic coating is 0.1 to 0.5 mm to obtain a hydrophobic anti-icing coating.

[0168] Step 3: Fabrication of internal pressure-bearing protective layer

[0169] Step 3.1: Mix XYPEX admixture, cement, fiber and filler in a certain proportion and put them into a mixer to mix them to ensure that all raw materials are fully mixed to form a uniform slurry.

[0170] Step 3.2: Pour the mixed slurry into the mold to half the height, then place the wire mesh into the slurry in the mold, keeping the wire mesh in the middle of the slurry; then arrange the second anchor nuts in a square at the four corners and fix them on the wire mesh, and ensure that the spacing between adjacent bolts is 500mm, and the arrangement position corresponds to the first anchor nut one by one; finally, inject the mixed slurry into the mold to the standard height (the thickness of the fiber cement board determined in step 1.2), and use a 7000-ton flattening machine and a pressing machine to flatten and press, and then maintain the shape.

[0171] Step 3.3: Determine the size according to step 1.4, cut and shape the fiber cement board, and reserve insertion holes for the concrete casting formwork anchor bolts and concrete casting formwork support legs at the corresponding positions to obtain the internal pressure-bearing protective layer.

[0172] Step 4: Casting and extrusion of insulation core layer

[0173] Step 4.1: Insert the two limiting flanges into the two ends of the insulation screw respectively.

[0174] Step 4.2: Place the rough surface of the facing anti-seepage protective layer parallel to the rough surface of the internal pressure-bearing protective layer. Thread the threaded sections of multiple insulation screws into the first and second anchor nuts, respectively, to connect the facing anti-seepage protective layer and the internal pressure-bearing protective layer into a single unit. Then, seal the entire surface with a template, leaving only one pouring port, to create a six-sided, airtight casting mold.

[0175] Step 4.3: Use the pouring and extrusion one-step molding process to fill the inside of the mold with polyurethane rigid foam insulation material; after the shape is finalized, remove the templates around it.

[0176] Step 4.4: Use power tools, electric saws and other tools to insert the reserved concrete pouring formwork anchor bolts and concrete pouring formwork support legs into the holes on the surface anti-seepage protective layer and the internal pressure-bearing protective layer, and drill through the insulation core layer. The hole size should be consistent with the protective layer.

[0177] Step 4.5: Use tools such as electric saws and hand saws to cut and trim the four sides, and form a mortise and tenon structure according to the principle of upper and lower correspondence and left and right correspondence, so as to form a seamless connection when multiple modules are spliced ​​and installed.

[0178] Example 3: A construction method for a template-embedded permanent thermal insulation protection module for a dam surface, comprising the following steps:

[0179] Step 1: Transportation and hoisting;

[0180] According to the dam concrete pouring schedule, the prefabricated template embedded permanent insulation modules for the dam surface are transported in batches to the construction site warehouse. Then, based on the daily concrete storage area, these modules are hoisted and transported to the storage surface via a cable crane.

[0181] Step 2: Embedded splicing installation of template;

[0182] Step 2.1: After the concrete pouring formwork is erected, the module's anti-seepage protective layer is placed against the concrete pouring formwork. A balancing cushion layer is laid between the inside of the concrete pouring formwork and the module's outer surface. This balancing cushion layer can be made of foam pads, plywood, polyethylene film, PET film, or EVA film. This cushion layer acts as a buffer for the module's protective layer during concrete pouring, preventing it from cracking under pressure. It also prevents release agents and oil stains from the concrete pouring formwork from contaminating the protective layer and preventing adhesion when the formwork is removed. During placement, insert the positioning cone and formwork support legs through the reserved holes into the warehouse.

[0183] Step 2.2: Install adjacent modules according to the corresponding mortise and tenon joint structure. Before joining, apply an adhesive such as structural adhesive or foam adhesive evenly to the tenon surface. Then insert the tenon into the corresponding mortise groove to ensure a seamless connection between adjacent modules.

[0184] Step 2.3: Use support rods, pads, etc. to fix the assembled modules on the concrete surface or the surface crack-limiting steel bars in the silo to prevent the modules from shifting or deviating from the concrete pouring formwork and falling into the silo when the concrete is put into the silo and vibrated.

[0185] Step 2.4: Screw the threaded ends of multiple serpentine anchor bars into the second anchor nut of the internal pressure-bearing protective layer, with the other ends facing into the warehouse. After the concrete is poured, the serpentine anchor bars and the dam body form a whole, firmly fixing the embedded dam surface permanent insulation and anti-seepage protection integrated system module.

[0186] Step 2.5: Use edge protection covers to temporarily seal the top surface of the uppermost module to prevent the concrete slurry from contaminating the mortise and tenon joint structure of the module during pouring, and to prevent damage to the insulation core layer during flushing.

[0187] Step 3: Inspection and sealing;

[0188] Step 3.1: When removing the concrete pouring formwork after concrete pouring, first unscrew the concrete pouring formwork anchor bolts connected to the positioning cone on the outside, and lift the concrete pouring formwork upward along the module surface; after the upper formwork support and panel are installed, remove the concrete pouring formwork support legs of the lowest formwork support from the insertion hole, finally exposing the decorative anti-seepage protective layer of the concrete dam surface of the warehouse.

[0189] Step 3.2: Use a ladder or other tool to hang from the upper formwork support and descend to the dam surface for inspection and sealing. First, use polyurethane foam to seal the positioning cone holes and the formwork support leg insertion holes. When the seal is 1 cm from the surface, use polymer mortar to seal it. Then, apply a 1-2 mm thick layer of XYPEX anti-seepage material to the surface. Finally, apply a 0.1-0.5 mm thick layer of hydrophobic material. This completes the permanent thermal insulation and anti-seepage protective layer for the concrete dam surface.

[0190] Step 3.3: After the formwork of the next warehouse is erected, remove the protective cover on the top of the installed module, and install the new module on the top of the installed module according to the mortise and tenon structure. Then repeat the above steps. When the dam is poured, the permanent thermal insulation protection module embedded in the formwork of the entire dam surface is also arranged, realizing the protection of the dam concrete throughout its life cycle.

[0191] The above embodiments are merely preferred technical solutions of the present invention and should not be construed as limiting the present invention. The scope of protection of the present invention shall be the technical solutions set forth in the claims, including equivalent alternatives to the technical features of the technical solutions set forth in the claims. In other words, equivalent alternatives and improvements within this scope are also within the scope of protection of the present invention.

Claims

1. A template embedded permanent thermal insulation protection module for dam surface, comprising a thermal insulation core layer (4), characterized in that: The side of the thermal insulation core layer (4) close to the concrete casting formwork (6) is provided with a decorative anti-seepage protective layer (1), the side of the thermal insulation core layer (4) close to the dam surface crack-limiting steel bars (7) is provided with an internal pressure-bearing protective layer (2), a thermal break bridge support keel (3) is provided inside the thermal insulation core layer (4), and an anchoring device (5) is provided in the area between the internal pressure-bearing protective layer (2) and the dam surface crack-limiting steel bars (7).

2. A template embedded permanent thermal insulation protection module for dam surface according to claim 1, characterized in that: The surface anti-seepage protective layer (1) is provided with a hydrophobic anti-icing coating (1.1), a cement-based anti-seepage coating (1.2) and a base protective layer (1.3) in sequence from the side in contact with the concrete casting template (6) toward the inner side of the dam; the base protective layer (1.3) comprises a first fiber cement board (1.3.1) and a first steel wire mesh (1.3.2) arranged in the first fiber cement board (1.3.1).

3. The template embedded permanent thermal insulation protection module for dam surface according to claim 1 is characterized by: The internal pressure-bearing protective layer (2) comprises a second fiber cement board (2.1) and a second steel wire mesh (2.2) arranged inside the second fiber cement board (2.1).

4. The template embedded permanent thermal insulation protection module for dam surface according to claim 1 is characterized by: The thermal break bridge support keel (3) comprises a first anchor nut (3.1) arranged in the surface anti-seepage protective layer (1) and a second anchor nut (3.2) arranged in the internal pressure-bearing protective layer (2); the first anchor nut (3.1) and the second anchor nut (3.2) are threadedly matched with two ends of the thermal insulation screw (3.3); the thread directions of the first anchor nut (3.1) and the second anchor nut (3.2) are opposite.

5. A template embedded permanent thermal insulation protection module for dam surface according to claim 4, characterized in that: The insulating screw (3.3) is provided with a groove or a step on a side close to the first anchor nut (3.1), and an outer limiting flange (3.4) in contact with the surface anti-seepage protective layer (1) is penetrated through the groove or the step; the insulating screw (3.3) is provided with a groove or a step on a side close to the second anchor nut (3.2), and an inner limiting flange (3.5) in contact with the internal pressure-bearing protective layer (2) is penetrated through the groove or the step.

6. The template embedded permanent thermal insulation protection module for dam surface according to claim 1 is characterized by: The anchoring device (5) comprises an adjustable support rod (5.1) arranged between the internal pressure-bearing protective layer (2) and the dam surface crack-limiting steel bars (7), and an anchor bar (5.2) threadedly connected to the outer side of the second anchor nut (3.2).

7. The template embedded permanent thermal insulation protection module for dam surface according to claim 1 is characterized by: Insertion holes for installing concrete casting template anchor bolts (8) and concrete casting template support legs (9) are provided in the concrete casting template (6), the surface anti-seepage protective layer (1), the thermal insulation core layer (4) and the internal pressure-bearing protective layer (2); the concrete casting template anchor bolts (8) are threadedly matched with one end of the positioning cone (10); the other end of the positioning cone (10) is connected to the dam surface crack-limiting steel bars (7) through a serpentine anchor bar (11); the concrete casting template support legs (9) are fixedly connected to the concrete casting template brackets (12).

8. The template embedded permanent thermal insulation protection module for dam surface according to claim 1 is characterized by: One end of the thermal insulation core layer (4) is higher than the end planes of the facing anti-seepage protective layer (1) and the internal pressure-bearing protective layer (2), forming a tenon structure; the other opposite end of the thermal insulation core layer (4) is lower than the end planes of the facing anti-seepage protective layer (1) and the internal pressure-bearing protective layer (2), forming a tenon structure; and each two adjacent template-embedded dam surface permanent thermal insulation protection modules are connected by the cooperation of the tenon structure and the tenon structure.

9. A method for prefabricating the template-embedded permanent thermal insulation protection module for dam surface according to any one of claims 1 to 8, characterized in that: It includes the following steps: Step 1: Parameter determination; Step 1.1: Determine the thickness of the insulation core layer according to the equivalent heat release coefficient of the insulation layer required by the dam design; Where: δ is the thickness of the insulation core layer, unit is m; γ is the thermal conductivity, unit is W / (m·K); β is the equivalent heat release coefficient, unit is W / m 2 ·K; k is the correction value: k is 1 to 1.

2. When the adhesive joint is airtight, k=1.2; Step 1.2: Calculate the lateral pressure during dam concrete pouring, check it with the shear strength of the fiber cement board of the facing anti-seepage protective layer and the internal pressure-bearing protective layer, and determine the thickness of the fiber cement board; The flexural strength of 1cm fiber cement board is 12MPa. max ×10 -3 When <12, the thickness H of the fiber cement board is 1 cm; When P max ×10 -3 When ≥12, the thickness H of the fiber cement board is calculated as follows: Where H: thickness of fiber cement board, unit: m; P max : Maximum lateral pressure of concrete, unit: kPa; Step 1.3: According to the thickness of the insulation core layer δ and the thickness of the fiber cement board H, the total length of the insulation screw and the length of the thicker middle section are calculated as follows: L 中 =(δ-h Ⅰ -h Ⅱ ); Where: L is the length of the insulation screw, in m; δ is the thickness of the insulation core layer, in m; H Ⅰ H is the height of the first anchor nut, in m; Ⅱ is the height of the second anchor nut, in m; h Ⅰ h is the thickness of the outer limit flange, Ⅱ is the thickness of the inner limit flange; Step 1.4: Determine the size and weight of a single module; Step 2: Manufacturing of surface anti-seepage protective layer; Step 2.1: Mix the XYPEX admixture, cement, fiber and filler raw materials in a certain proportion and send them into a mixer for stirring to ensure that all raw materials are fully mixed to form a uniform slurry; Step 2.2: Inject the mixed slurry into the mold to half the height, then put the wire mesh into the slurry in the mold, keeping the wire mesh in the middle of the slurry; then arrange the first anchor nut in a square shape and fix it on the wire mesh; finally, inject the mixed slurry into the mold to the thickness of the fiber cement board determined in step 1.2, and use a flattening machine and a pressing machine to flatten and press it, and then maintain and shape it; Step 2.3: Cut and shape the fiber cement board according to the size determined in step 1.4, and reserve insertion holes for the concrete casting formwork anchor bolts and the concrete casting formwork support legs at corresponding positions to obtain a base protective layer; Step 2.4: Apply a layer of XYPEX anti-seepage material on the smooth surface of the base protective layer to obtain a cement-based anti-seepage coating; Step 2.5: Apply a layer of hydrophobic coating on the surface of the cement-based anti-seepage coating to obtain a hydrophobic anti-icing coating; Step 3: Manufacturing of internal pressure-bearing protective layer: Step 3.1: Mix the XYPEX admixture, cement, fiber and filler raw materials in a certain proportion and send them into a mixer for stirring to ensure that all raw materials are fully mixed to form a uniform slurry; Step 3.2: Inject the mixed slurry into the mold to half the height, then put the wire mesh into the slurry in the mold, keeping the wire mesh in the middle of the slurry; then arrange the second anchor nut in a square shape and fix it on the wire mesh, with the arrangement position corresponding to the first anchor nut; finally, inject the mixed slurry into the mold to the thickness of the fiber cement board determined in step 1.2, and use a flattening machine and a pressing machine to flatten and press it, and then maintain and shape it; Step 3.3: Determine the size according to step 1.4, cut the fiber cement board into shape, and reserve insertion holes for the concrete casting formwork anchor bolts and the concrete casting formwork support legs at corresponding positions to obtain an internal pressure-bearing protective layer; Step 4: pouring and extruding the insulation core layer; Step 4.1: Insert the two limiting flanges into the two ends of the insulation screw respectively; Step 4.2: Place the rough surface of the facing anti-seepage protective layer and the rough surface of the internal pressure-bearing protective layer in parallel, screw the threaded sections at both ends of the multiple heat-insulating screws into the first anchor nut and the second anchor nut respectively, and connect the facing anti-seepage protective layer and the internal pressure-bearing protective layer to form a whole; then use a template to seal the surroundings, leaving only one pouring port, to form a 6-sided sealed casting mold; Step 4.3: Use the pouring and extrusion one-step molding process to fill the inside of the mold with polyurethane rigid foam insulation material; remove the templates around it after the molding is finalized; Step 4.4: Use tools to drill through the reserved holes for the concrete casting template anchor bolts and the concrete casting template support legs on the facing anti-seepage protective layer and the internal pressure-bearing protective layer, and drill through the insulation core layer; Step 4.5: Cut and trim the four sides, and form a mortise and tenon structure according to the principle of upper and lower correspondence and left and right correspondence, so as to form a seamless connection when multiple modules are spliced ​​and installed.

10. A construction method for the template embedded permanent thermal insulation protection module for dam surface according to any one of claims 1 to 8, characterized in that: It includes the following steps: Step 1: Transportation and hoisting; According to the dam concrete pouring progress, the prefabricated template embedded dam surface permanent insulation protection modules are transported in batches to the construction site warehouse; then, according to the daily concrete storage area, these modules are hoisted and transported to the warehouse surface by cable crane; Step 2: Template embedded splicing installation: Step 2.1: After the concrete casting formwork is erected, the surface anti-seepage protective layer of the above-mentioned module is arranged close to the casting formwork, and a balancing cushion is laid between the inner side of the concrete casting formwork and the outer surface of the module. First, it plays a buffering role on the surface protection layer of the module during concrete casting to prevent it from being ruptured under pressure; second, it prevents the release agent and oil stains on the concrete casting formwork from polluting the surface anti-seepage protective layer and avoids the two from being bonded together when the formwork is removed; when arranging, the concrete casting formwork anchor bolts and the concrete casting formwork support legs are passed through the reserved insertion holes into the warehouse, and the concrete casting formwork anchor bolts are threadedly connected to one end of the positioning cone. At this time, the other end of the positioning cone is connected to the surface crack-limiting steel bar of the dam through a serpentine anchor bar; Step 2.2: Install adjacent modules in accordance with the principle of corresponding mortise and tenon joint structures; before joining, apply adhesive evenly on the surface of the tenon, and then insert the tenon into the corresponding tenon groove to ensure seamless connection between adjacent modules up, down, left, and right; Step 2.3: Adjust the length of the adjustable support rods according to the actual distance between the assembled modules and the surface crack-limiting steel bars of the dam, and install and fix them to prevent the modules from shifting or deviating from the concrete pouring template and falling into the warehouse when the concrete is put into the warehouse and vibrated; Step 2.4: Screw the threaded ends of multiple anchor bars into the second anchor nut of the internal pressure-bearing protective layer, with the other end facing the interior of the bin. After the concrete is poured, the anchor bars and the dam body form a whole, thereby firmly fixing the template-embedded permanent thermal insulation protection module of the dam surface; Step 2.5: Use edge sealing protection cover to temporarily seal the top surface of the uppermost module to prevent the concrete slurry from contaminating the mortise and tenon structure of the module during pouring, and to prevent the insulation core layer from being damaged during flushing; Step 3: Inspection and sealing; Step 3.1: When removing the concrete pouring formwork after concrete pouring, first unscrew the concrete pouring formwork anchor bolts connected to the positioning cone on the outside, and lift the concrete pouring formwork upward along the module surface; after the upper formwork support and panel are installed, remove the concrete pouring formwork support legs of the lowest formwork support from the insertion hole, and finally expose the surface anti-seepage protective layer of the silo concrete dam surface; Step 3.2: Use the tool to hang on the bracket of the upper template, and people go down to the dam surface along the tool to inspect and seal; Step 3.3: After the formwork of the next warehouse is erected, remove the protective cover on the top of the installed module, and install the new module on the top of the installed module according to the mortise and tenon structure, and then repeat the above steps. When the dam is poured, the permanent thermal insulation protection module embedded in the formwork of the entire dam surface is also arranged, realizing the protection of the dam concrete throughout its life cycle.

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