Fireproof water-resistant thermal insulation composite isolation belt for existing building outer wall and construction method thereof

Abstract

The application discloses a fireproof water-blocking heat-insulating composite isolation belt for an existing building outer wall and a construction method thereof, and belongs to the technical field of repair and fireproof and thermal insulation of an existing building outer wall. The composite isolation belt is arranged in a combustible insulation layer outside a base wall, a discontinuous belt penetrating through the thickness of the combustible insulation layer is formed in a horizontal direction, and inorganic insulation boards are embedded in the discontinuous belt to block the continuous distribution of the combustible insulation layer. A polymer cement water-proof bonding layer is arranged in the discontinuous belt, and a three-way fiber anti-cracking layer is arranged outside the inorganic insulation boards; the composite isolation belt and the outer sides of adjacent wall surfaces are dry-laid with anti-cracking stainless steel meshes, and the anti-cracking stainless steel meshes are fixed to the base wall through anchor bolts, and the outer sides of the anti-cracking stainless steel meshes are sequentially provided with a water-proof anti-cracking reinforcing layer and a water-proof heat-insulating finishing layer. The application can consider fireproof isolation, water-blocking and anti-cracking, heat preservation and insulation and overall reinforcement of the wall surface.

Description

Technical Field

[0001] This invention relates to the field of existing building exterior wall repair and building fireproofing and thermal insulation technology, specifically to a fireproof, water-blocking and heat-insulating composite isolation strip for existing building exterior walls and its construction method. Background Technology

[0002] When existing building exterior walls use combustible or flame-retardant insulation materials, long-term exposure to sunlight, rain, freeze-thaw cycles, and temperature fluctuations can easily lead to problems such as peeling, cracking, hollowing, water seepage, and localized adhesion failure. When combustible insulation layers are continuously installed along the building's height, flames and high temperatures may continue to spread along the insulation layer; if the original insulation system is completely removed and rebuilt, the project will be extensive and will increase construction waste.

[0003] Current repair methods often focus on localized repairs, surface plastering, or the addition of ordinary fireproof insulation materials, with insufficient consideration given to water barrier between the insulation strip and the base layer, crack resistance at the interface between new and old materials, and overall mechanical reinforcement of the existing insulation layer. When relying solely on mortar bonding or ordinary fiber mesh reinforcement, the repaired layer may still experience cracks, hollow areas, leaks, or partial detachment.

[0004] Therefore, there is an urgent need for a fireproof, water-blocking, and heat-insulating composite insulation structure and construction method suitable for the exterior walls of existing buildings. This structure should achieve fireproofing of the combustible insulation layer, water blocking at the base interface, crack resistance at the junction of new and old materials, mechanical anchoring of the wall surface, and waterproof and heat-insulating protection of the exterior finish, while retaining the original insulation system that can still be used.

[0005] A search revealed a Chinese patent document disclosing a fireproof isolation strip for external wall insulation [Application No.: 202311804986.3, Publication No.: CN117758876A]. This document discloses a composite sandwich fireproof isolation strip composed of a first fireproof board, a second fireproof board, and insulation material between them. Carbon fiber cloth is placed between the insulation material and the first fireproof board. The fireproof isolation strip is laid on the wall through an adhesive layer and fixed by anchors that penetrate the insulation layer, adhesive layer, and wall. A plaster layer and a finishing layer are sequentially applied to the outside of the insulation layer. Its main purpose is to improve the fireproof and heat insulation performance and structural strength of the isolation strip by utilizing double-layer fireproof boards, insulation material, and carbon fiber cloth.

[0006] While the comparative patent can prevent flame spread and reduce heat transfer through a composite sandwich structure composed of double-layer fireproof boards and heat insulation materials, featuring lightweight structure, high board strength, and the ability to be fixed through adhesive layers and anchors, this invention targets existing building exterior walls with existing combustible insulation layers. It forms a horizontal break by partially removing the original combustible insulation material and embedding inorganic insulation boards, while simultaneously forming a continuous waterproof bonding structure on the base wall and the upper and lower sidewalls of the break. A multi-level reinforcement structure is formed through a triaxial fiber crack-resistant layer spanning the interface between new and old materials, dry-hanging crack-resistant stainless steel mesh, and anchors directly anchored into the base wall. This invention also includes a waterproof crack-resistant reinforcement layer and a continuous waterproof and heat-insulating finishing layer, thus possessing comprehensive treatment capabilities for existing exterior walls, including partial repair, interface water blocking, crack resistance at the interface between new and old materials, overall mechanical reinforcement of the wall surface, and waterproof and heat-insulating exterior finishes, which are not disclosed in the comparative patent. Summary of the Invention

[0007] In view of the problems existing in the prior art, the purpose of this invention is to provide a fireproof, water-blocking and heat-insulating composite isolation strip for the exterior walls of existing buildings and its construction method.

[0008] A fireproof, water-blocking, and heat-insulating composite insulation strip for the exterior walls of existing buildings, installed in the combustible insulation layer on the outside of the base wall, characterized in that: The combustible insulation layer has a horizontally continuous break strip that extends through its thickness. The break strip is filled with an inorganic insulation board with an inorganic material matrix and a combustion performance rating of not less than A2. A polymer cement waterproof bonding layer is continuously provided between the inorganic insulation board and the base wall and the upper and lower sidewalls of the break strip, and a triaxial fiber crack-resistant layer is provided on the outer side of the inorganic insulation board that crosses its upper and lower boundaries. The composite isolation strip and its adjacent outer side are continuously provided with crack-resistant stainless steel mesh. There is no bonding mortar layer or adhesive layer between the crack-resistant stainless steel mesh and the wall. The crack-resistant stainless steel mesh is directly anchored to the base wall by anchor bolts that pass through the existing external wall insulation system. A waterproof crack-resistant reinforcement layer and a waterproof heat insulation finishing layer are provided in sequence on the outer side of the crack-resistant stainless steel mesh.

[0009] Preferably, the width of the break strip along the vertical direction of the wall is 500mm, and the composite isolation strip is set every five floors along the building height direction; the inorganic insulation board completely replaces the combustible insulation layer in the break strip along the wall thickness direction.

[0010] The above technical solution can create multi-level horizontal fire-resistant isolation zones along the height of existing building exterior walls. The 500mm wide break strip increases the distance that flames and high temperatures can travel upwards across the composite isolation strip. The inorganic insulation board completely replaces the combustible insulation layer within the break strip, preventing residual combustible materials inside and thus improving the vertical spread of fire on the exterior wall.

[0011] Specifically, a composite firebreak is installed every five floors, dividing the continuously distributed combustible insulation layer along the building's height into multiple relatively independent zones. When the combustible insulation material in a certain zone ignites, the composite firebreak above it can block the further spread of flames and high temperatures. The inorganic insulation board completely replaces the original combustible insulation layer along the wall thickness, and also eliminates the connection path of combustible material penetrating the firebreak, preventing the formation of localized weak points in fire resistance.

[0012] In practical applications, the above-mentioned composite isolation strip arrangement method can carry out segmented fireproofing of the existing building exterior walls without completely dismantling the existing exterior wall insulation system. This can reduce the amount of demolition work and maintain the original insulation function of the undamaged areas. It is suitable for the renovation projects of existing buildings with a certain building height and combustible exterior wall insulation materials.

[0013] Preferably, the inorganic insulation board is an insulation board with inorganic material as the matrix and without adding halogenated flame retardants to achieve fire resistance. Its combustion performance rating is not lower than A2, its density is 120-350 kg / m³, its thermal conductivity is not greater than 0.070 W / (m·K), and its volume water absorption rate is not greater than 5%. The thickness of the inorganic insulation board is not more than 2 mm different from the thickness of the adjacent combustible insulation layer, and the height difference between its outer surface and the outer surface of the adjacent combustible insulation layer is not more than 2 mm.

[0014] The above technical solutions enable inorganic insulation boards to simultaneously possess fire resistance, thermal insulation, water absorption resistance, and dimensional adaptability. Insulation boards using inorganic materials as the matrix can achieve stable fire resistance without relying on halogenated flame retardants. Simultaneously, by limiting the thermal conductivity and volumetric water absorption rate, the composite insulation strip maintains corresponding thermal insulation and water resistance properties while blocking the combustible insulation layer.

[0015] Specifically, limiting the combustion performance rating of inorganic insulation boards to no less than A2 reduces the possibility of the insulation strip itself participating in combustion; limiting the density to 120-350 kg / m³ helps to balance the mechanical strength and construction weight of the boards; limiting the thermal conductivity to no more than 0.070 W / (m·K) reduces the formation of significant horizontal thermal bridges in the insulation strip area; and limiting the volumetric water absorption rate to no more than 5% reduces the risk of decreased thermal conductivity, volume changes, or damage to the interface with adjacent materials after the boards absorb water.

[0016] In practical applications, by controlling the thickness difference and the height difference of the outer surface between the inorganic insulation board and the adjacent combustible insulation layer to within 2mm, the new and old insulation materials can be smoothly connected, providing a flat base layer for the continuous construction of the triaxial fiber anti-cracking layer, stainless steel mesh and outer surface finishing layer, and reducing the possibility of stress concentration, hollowing or cracking caused by surface height difference and material deformation difference.

[0017] Preferably, the polymer cement waterproof bonding layer includes a two-component interface agent layer disposed on the surface of the base wall and a polymer cement waterproof slurry layer disposed on the outside of the two-component interface agent layer; the polymer cement waterproof slurry layer continuously covers the base wall and the upper and lower sidewalls of the break zone, with a total thickness of 1.5-2.5mm, and extends 50-100mm outward from the upper and lower boundaries of the break zone, respectively.

[0018] The above technical solution enables the formation of a continuous waterproof bonding interface between the inorganic insulation board and the base wall. The two-component interface agent layer can solidify the powdery particles on the surface of the base wall and improve the bonding conditions of subsequent materials, while the polymer cement waterproof slurry layer can seal the capillaries, micro-cracks, and construction joints on the surface of the base wall, thus achieving both interface bonding and water-blocking effects.

[0019] Specifically, the polymer cement waterproof slurry layer not only covers the base wall within the break zone, but also continuously covers the upper and lower sidewalls of the break zone, extending 50-100mm outward from the boundary of the break zone, so that the waterproof structure spans the interface between the inorganic insulation board and the original combustible insulation layer. This continuous coverage method can extend the path of moisture migration into the wall along the interface between the old and new materials, reducing the possibility of rainwater or water vapor entering the existing insulation system from the edge of the break zone.

[0020] In practical applications, controlling the total thickness of the polymer cement waterproof slurry layer to 1.5-2.5mm ensures the continuity of the waterproof layer while avoiding problems such as drying shrinkage cracking or construction difficulties caused by excessive coating thickness. This structure is suitable for situations where there are differences in the flatness and water absorption rate of existing wall surfaces, which helps improve the bonding stability and long-term water-blocking performance between the composite isolation strip and the base wall.

[0021] Preferably, the triaxial fiber crack-resistant layer comprises a polymer crack-resistant and seepage-proof mortar layer with a thickness of 3-5 mm and a triaxial fiber reinforcing mesh embedded within the polymer crack-resistant and seepage-proof mortar layer; the triaxial fiber reinforcing mesh has longitudinal, transverse, and oblique reinforcing fiber bundles, and a unit area mass of 180-300 g / m². 2 Its upper and lower edges extend beyond the upper and lower boundaries of the inorganic insulation board and overlap the outer side of the adjacent combustible insulation layer, with an overlap width of 100-150mm.

[0022] The above technical solution enables multi-directional crack resistance reinforcement of the surface of inorganic insulation boards and the interface between inorganic insulation boards and adjacent combustible insulation layers. The triaxial fiber reinforcement mesh can withstand and disperse tensile and shear stresses in different directions along the longitudinal, transverse, and oblique directions, while the polymer crack-resistant and seepage-proof mortar layer can cover the reinforcement mesh and form a continuous crack-resistant and seepage-proof structure.

[0023] Specifically, inorganic insulation boards and existing combustible insulation layers may differ in density, water absorption, shrinkage, and temperature deformation properties. Under temperature cycling, humidity changes, and wind loads, stress concentration can easily occur at the interface between the old and new materials. Triaxial fiber reinforced mesh, spanning the upper and lower boundaries of the inorganic insulation board and overlapping to the outside of the adjacent combustible insulation layer, can disperse the localized stress generated at the interface over a wider area, reducing the likelihood of cracks concentrating along the edges of the board.

[0024] In practical applications, the unit area mass of triaxial fiber reinforced mesh is limited to 180-300 g / m². 2 The overlap width is controlled at 100-150mm to balance reinforcement effect, mortar coverage performance, and ease of construction. A 3-5mm thick polymer crack-resistant and seepage-proof mortar layer allows the reinforcing mesh to be stably embedded within it, preventing the mesh from being exposed, while providing a continuous and flat construction base for the subsequent aluminum composite layer and finishing restoration layer.

[0025] Preferably, an aluminum-coated composite layer is provided on the outside of the triaxial fiber crack-resistant layer. The aluminum-coated composite layer is formed by bonding aluminum foil and alkali-resistant glass fiber cloth with weather-resistant adhesive, and its thickness is 0.2-0.8mm. A surface restoration layer that connects with the existing exterior wall finish is provided on the outside of the aluminum-coated composite layer.

[0026] The above technical solution enables the formation of a continuous protective and transitional structure on the outer side of the triaxial fiber anti-cracking layer. The aluminum foil provides a certain barrier against external heat radiation and moisture intrusion, the alkali-resistant glass fiber cloth improves the tensile strength and dimensional stability of the aluminum-coated composite layer, and the weather-resistant adhesive ensures a stable bond between the aluminum foil and the alkali-resistant glass fiber cloth.

[0027] Specifically, the aluminum-coated composite layer covers the outside of the triaxial fiber anti-cracking layer, which can reduce the direct impact of subsequent construction and external environment on the triaxial fiber reinforced mesh and polymer anti-cracking and seepage-proof mortar layer. After the aluminum foil, alkali-resistant glass fiber cloth and weather-resistant adhesive form a composite structure, it can take into account surface continuity, flexibility and weather resistance, and form a relatively stable transition interface on the outside of the composite isolation strip.

[0028] In practical applications, controlling the thickness of the aluminum composite layer to 0.2-0.8mm can prevent the composite layer from being too thick and affecting the flatness of the wall surface, while ensuring that it has the corresponding covering and reinforcing functions. The finishing restoration layer set on the outside of the aluminum composite layer can level the surface of the composite isolation strip, making it smoothly connected with the adjacent existing wall surface in terms of height and surface texture, creating conditions for the continuous laying of subsequent crack-resistant stainless steel mesh.

[0029] Preferably, the waterproof and crack-resistant reinforcement layer is formed by waterproof and crack-resistant reinforcement paste, and the waterproof and heat-insulating finishing layer includes a waterproof and heat-insulating intermediate coating layer and a water-based self-cleaning topcoat layer; the two-component interface agent, polymer cement waterproof slurry, waterproof and crack-resistant reinforcement paste, waterproof and heat-insulating intermediate coating, and water-based self-cleaning topcoat are all water-based materials; the thickness of the waterproof and crack-resistant reinforcement layer is 2-4mm, and the waterproof and heat-insulating intermediate coating layer is formed by two coats of waterproof and heat-insulating intermediate coating, continuously covering the composite isolation strip and adjacent wall surfaces.

[0030] The above technical solutions enable the formation of a continuous waterproof, crack-resistant, and heat-insulating protection system on the composite isolation zone and the outer side of adjacent walls. The use of water-based interface agents, waterproof slurries, waterproof and crack-resistant reinforcing pastes, waterproof and heat-insulating intermediate coats, and water-based self-cleaning topcoats reduces the use of organic solvents and volatile substances during construction, thus improving the construction environment for existing building repairs.

[0031] Specifically, a 2-4mm thick waterproof and crack-resistant reinforcement layer can penetrate the mesh of the crack-resistant stainless steel mesh and bond with the inner wall surface. It also covers the stainless steel mesh and anchor bolt heads, forming a unified whole with the mesh, anchor bolts, and wall surface. The waterproof and heat-insulating intermediate coating is applied in two coats. The second coat covers any missed areas, pinholes, or weak spots from the first coat, thus improving the continuity and uniformity of the membrane layer.

[0032] In practical applications, the waterproof and heat-insulating intermediate coating continuously covers the composite isolation strip and adjacent walls, avoiding the formation of new seams and weak points for water seepage caused by only partially coating the isolation strip area. The water-based material system is also suitable for construction conditions involving large areas of existing building exterior walls, long construction periods, and high levels of surrounding human activity, which helps improve the environmental friendliness of the renovation project and the overall protective effect of the exterior walls.

[0033] A construction method for a fireproof, water-blocking, and heat-insulating composite insulation strip for the exterior walls of existing buildings, characterized by the following steps: S1. Inspect the exterior walls of existing buildings and mark areas with hollow spots, cracks and areas to be removed. Cut and remove the areas to be removed down to the base wall, remove loose dust and debris, and perform interface treatment and repair leveling on the wall surface. S2. In the combustible insulation layer, a 500mm wide, continuous strip is formed horizontally every five floors. S3. Apply a two-component interface agent and polymer cement waterproof slurry to the surface of the base wall and the upper and lower side walls of the disconnected zone to form a continuous polymer cement waterproof bonding layer. S4. An inorganic insulation board with an inorganic material matrix and a fire performance rating of not less than A2 is embedded in the break strip, so that the inorganic insulation board completely replaces the combustible insulation layer in the break strip along the wall thickness direction, and the thickness difference and the outer surface height difference between the inorganic insulation board and the adjacent combustible insulation layer do not exceed 2mm. S5. Apply polymer crack-resistant and seepage-proof mortar to the outside of the inorganic insulation board, and lay a triaxial fiber reinforced mesh that spans the upper and lower boundaries of the inorganic insulation board. Then apply the aluminum composite layer and the decorative restoration layer. S6. Dry-lay anti-crack stainless steel mesh continuously on the outside of the composite isolation strip and adjacent wall surface, so that the anti-crack stainless steel mesh is unfolded and attached to the wall surface, without pre-applying adhesive mortar or adhesive material between the anti-crack stainless steel mesh and the wall surface; use a dust-free water drill to drill through the anti-crack stainless steel mesh and the existing external wall insulation system, and anchor the anti-crack stainless steel mesh directly to the base wall through anchor bolts. S7. Construct a waterproof and crack-resistant reinforcement layer on the outside of the crack-resistant stainless steel mesh and anchor bolts, and construct a waterproof and heat-insulating finishing layer on the outside of the waterproof and crack-resistant reinforcement layer.

[0034] Preferably, in step S3, the polymer cement waterproof slurry is applied in two cross-coats, with a thickness of 0.75-1.25mm for each coat, and the subsequent coat is applied after the previous coat has dried to the touch; the polymer cement waterproof slurry continuously covers the base wall and the upper and lower sidewalls of the break zone, and extends 50-100mm outward from the upper and lower boundaries of the break zone; in step S5, the triaxial fiber reinforced mesh is embedded in the middle of the polymer crack-resistant and seepage-proof mortar, with an overlap width of 100-150mm at its upper and lower edges.

[0035] The above technical solutions can improve the coating integrity of the polymer cement waterproof slurry layer and the stress stability of the triaxial fiber anti-crack layer. Applying the waterproof slurry in two cross-coats allows the application directions of the two coats to complement each other, reducing the possibility of missed areas, pinholes, or insufficient thickness caused by unidirectional application. The triaxial fiber reinforcement mesh embedded in the middle of the mortar ensures that both sides are covered by the mortar.

[0036] Specifically, applying the second coat of waterproofing slurry after the first coat has surface-dried avoids disturbance between the two coats or sagging, and ensures a continuous, bonded waterproof membrane. Extending the waterproofing slurry 50-100mm beyond the upper and lower boundaries of the break zone effectively seals the interface between the old and new materials. Overlapping the upper and lower edges of the triaxial fiber reinforced mesh by 100-150mm allows the reinforcement to extend beyond stress-concentrated boundaries, creating a continuous stress transfer zone.

[0037] In practical applications, the above-mentioned construction method of applying the coating in multiple coats, extending across boundaries, and embedding the reinforcing mesh in the center facilitates control over the thickness and coverage of each functional layer. This reduces the risk of local defects in the waterproofing layer and the exposure and corrosion caused by the reinforcing mesh being too close to the surface, or insufficient reinforcement due to its close proximity to the substrate. This allows the composite barrier to maintain good water-blocking and crack-resistant performance under long-term temperature changes and wet-dry cycles.

[0038] Preferably, in step S6, a 304 stainless steel mesh with a mesh size of 10mm×10mm and a wire diameter of 0.6-0.9mm is used. The crack-resistant stainless steel mesh is laid using a dry method, with adjacent crack-resistant stainless steel meshes overlapping by 100-150mm. Holes are drilled using a dust-free water drill, and anchor bolts are distributed in a quincunx pattern at 5-8 per square meter. The crack-resistant stainless steel mesh is directly pressed and fixed to the wall surface, and the effective anchoring depth of the anchor bolts is 25-50mm. In step S7, a waterproof crack-resistant reinforcing paste with a total thickness of 2-4mm is applied in two coats, followed by the sequential application of fine sand-type flexible crack-resistant putty for exterior walls, alkali-resistant penetrating sealing primer, waterproof and heat-insulating intermediate coat, multi-color coating, and water-based self-cleaning topcoat.

[0039] The above technical solution enables the reliable fixing of crack-resistant stainless steel mesh to the base wall, forming a continuous and complete waterproof, crack-resistant, and decorative protective structure on its outer side. 304 stainless steel mesh possesses good corrosion resistance and mechanical reinforcement properties. The dry-laying method does not rely on bonding mortar or adhesives for initial fixing of the mesh, and the anchor bolts can directly transfer the forces borne by the repair structure on the outer side of the wall to the base wall.

[0040] Specifically, the 10mm×10mm mesh size facilitates the penetration of waterproof and crack-resistant reinforcing compound to bond with the inner wall surface, while also creating a relatively uniform wall reinforcement grid. The 0.6-0.9mm wire diameter balances mesh strength, bending performance, and ease of installation. Adjacent stainless steel meshes overlap by 100-150mm to prevent continuous weak areas from forming at the mesh joints. Anchors are arranged in a staggered pattern of 5-8 per square meter, ensuring that the constraint ranges of adjacent anchor points interweave, which is beneficial for evenly transferring wall loads. An effective anchoring depth of 25-50mm ensures that the anchor's fixation is firmly established on the base wall.

[0041] In practical applications, using a dust-free water drill can reduce the impact of construction dust on the surrounding environment and the completed wall surface. Two coats of waterproof and crack-resistant reinforcing compound can completely cover the stainless steel mesh, mesh overlaps, and anchor bolt heads. The subsequent application of flexible crack-resistant putty, sealing primer, waterproof and heat-insulating intermediate coat, multi-color paint, and water-based self-cleaning topcoat can sequentially achieve fine leveling, base sealing, waterproofing and heat insulation, decorative restoration, and weather-resistant self-cleaning protection, thereby improving the integrity and durability of the existing building exterior wall repair structure.

[0042] Compared with the prior art, the present invention has the following advantages: 1. This invention creates horizontal breaks in the existing combustible insulation layer and replaces the combustible material in the corresponding areas with inorganic insulation boards, thus dividing the originally continuous insulation layer along the building height. Simultaneously, it preserves usable portions of the wall surface, treating only the defective areas and the isolation zones. This approach balances fire prevention modifications with the original insulation function, minimizing the impact of large-scale demolition on the existing walls and the normal operating environment.

[0043] 2. This invention combines base waterproofing and bonding, crack resistance at the interface between new and old materials, dry-hanging anchoring of stainless steel mesh, and exterior waterproof and heat-insulating finishing, creating a repair structure where different functional layers work together. The stainless steel mesh is directly fixed to the base wall with anchors, which can disperse the stress generated by wall deformation and reduce reliance on the bonding condition of the original insulation layer; combined with a continuous waterproof and surface protection structure, it helps to reduce the risk of water seepage, cracking, hollowing, and localized detachment. Attached Figure Description

[0044] Figure 1 This is a schematic diagram of the arrangement of the fireproof, water-blocking, and heat-insulating composite isolation strip of the present invention on the exterior wall of an existing building; Figure 2 This is a schematic diagram of the layered structure of the fireproof, water-blocking, and heat-insulating composite isolation strip and the adjacent exterior wall repair structure of the present invention. Figure 3 This is a schematic diagram showing the arrangement of the anti-crack stainless steel mesh and stainless steel anchors of the present invention on the composite isolation zone and adjacent wall surfaces. Figure 4 This is a construction flowchart of the fireproof, water-blocking, and heat-insulating composite isolation strip for the exterior walls of existing buildings according to the present invention. Detailed Implementation

[0045] The present invention will be further described below with reference to the accompanying drawings and embodiments. It should be understood that the following content is used to illustrate the implementation of the present invention and is not intended to limit the scope of protection of the present invention.

[0046] Working principle (1) Principles of overall renovation of existing building exterior walls and layout of isolation zones like Figures 1 to 4As shown, the present invention is applicable to the exterior walls of existing buildings with combustible exterior wall insulation materials, especially to existing buildings with hollow areas, cracks, water seepage, peeling and flaking of the finish, local failure of the insulation material, or decreased adhesion of the exterior wall insulation layer.

[0047] This invention does not involve the complete removal of existing external wall insulation systems that are still functional. Instead, it first inspects, cuts, cleans, treats, and repairs the defective areas of the wall. Then, a fireproof, water-blocking, and heat-insulating composite isolation strip is installed horizontally along the building's exterior wall within the existing combustible insulation layer. After the composite isolation strip is installed, a crack-resistant stainless steel mesh is continuously laid using a dry method on the outer side of the composite isolation strip and the repaired adjacent wall surface. The crack-resistant stainless steel mesh is directly anchored to the base wall using stainless steel anchors. Subsequently, a waterproof and crack-resistant reinforcement layer and a waterproof and heat-insulating finishing layer are sequentially constructed on the outer side of the crack-resistant stainless steel mesh.

[0048] During the installation of crack-resistant stainless steel mesh, no bonding mortar, adhesive, or waterproof crack-resistant reinforcement materials are used for pre-bonding. Instead, the mesh is unfolded, overlapped, and leveled along the wall surface, and then initially mechanically fixed using anchor bolts. The subsequent waterproof crack-resistant reinforcement layer passes through the mesh openings of the crack-resistant stainless steel mesh and bonds with the inner wall surface, thus covering the mechanically anchored crack-resistant stainless steel mesh.

[0049] like Figure 1 As shown, the fireproof, water-blocking, and heat-insulating composite isolation strip extends continuously horizontally along the exterior wall of the building, with a vertical width of 500mm along the wall surface, and is installed every five floors along the building height. When installing the composite isolation strip, the original finishing layer, crack-resistant layer, and combustible insulation material in the corresponding strip area are removed down to the base wall, so that the combustible insulation material that was originally installed continuously along the building height is interrupted at the composite isolation strip.

[0050] Through the above-mentioned repair methods, the composite isolation strip, the existing external wall insulation system, the local repair areas, the crack-resistant stainless steel mesh, and the base wall form an interconnected external wall repair structure. While preserving the functional parts of the existing external wall, the repaired external wall possesses corresponding fireproofing, waterproofing, crack resistance, thermal insulation, and mechanical reinforcement properties.

[0051] (2) Principles of wall inspection, base cleaning and repair according to Figure 4 The construction process shown involves inspecting the existing building's exterior walls using a combination of visual inspection and tapping before construction begins. Visual inspection is used to identify wall cracks, peeling of the finish layer, localized detachment, water seepage, discoloration, and uneven surfaces. Tapping is used to determine if there are any hollow areas between the finish layer, crack-resistant layer, insulation layer, or adjacent material layers.

[0052] Mark any hollow, cracked, or unremoved areas discovered during inspection, and cut along the boundary of the area to be treated. After cutting, remove any hollow, cracked, or poorly bonded finishing layers, crack-resistant layers, insulation materials, and original repair materials. When defects have extended into the insulation layer or the base layer interface, remove the corresponding portion down to the base wall.

[0053] By pre-cutting, a relatively neat boundary is formed between the area to be removed and the adjacent area to be retained, reducing disturbance to the adjacent intact wall surface during the removal process. After removal, use a brush, vacuum cleaner, or other cleaning tools to remove loose dust, debris, and loose particles from the base surface to prevent loose materials from getting trapped between the base wall and subsequent repair materials.

[0054] After the base layer is cleaned, apply a coat of two-component interface agent evenly to the wall surface to be repaired using a roller or brush. Once adhered to the base surface, the two-component interface agent solidifies any powdery particles and improves the bonding between the base wall and the insulation mortar, crack-resistant mortar, and subsequent functional materials. The two-component interface agent also reduces the difference in water absorption between different areas of the base layer, minimizing the possibility of decreased bond strength or cracking of subsequent construction materials due to excessive water loss.

[0055] After the interface treatment is completed, the removed areas are repaired and leveled. For areas where the original wall surface contained thermal insulation mortar, thermal insulation mortar is used for leveling; for areas where the original wall surface was a crack-resistant mortar layer, crack-resistant mortar is used for leveling. During the repair process, the repaired area is controlled to not be higher than the adjacent original wall surface, so that the repaired area is smoothly connected to the retained wall surface, providing a flat base for the subsequent continuous construction of crack-resistant stainless steel mesh and waterproof crack-resistant reinforcement layer.

[0056] (3) Internal structure and fireproof isolation principle of composite firebreak like Figure 2 As shown, the fireproof, water-blocking, and heat-insulating composite isolation strip includes, from the side closest to the base wall outwards, an interface agent layer, a polymer cement waterproof slurry layer, a crack-resistant and seepage-proof composite layer, an inorganic insulation board filling layer, a triaxial fiber crack-resistant layer, an aluminum composite layer, and a finishing restoration layer.

[0057] During the construction of the composite insulation strip, the original finishing layer, crack-resistant layer, and combustible insulation material within the strip area are removed down to the base wall. Then, each functional layer is constructed sequentially within the cleared strip area. An inorganic insulation board infill layer replaces the removed existing combustible insulation material along the wall thickness direction, thus disrupting the continuous distribution of the existing combustible insulation layer along the building's height.

[0058] When a fire breaks out in a section of the building's exterior wall, the flames and high temperatures spread upwards along the existing combustible insulation layer to the location of the composite isolation strip, where they are blocked by the inorganic insulation board filling layer. Because the inorganic insulation board filling layer is continuously installed horizontally along the building's exterior wall, and the composite isolation strip is 500mm wide vertically along the wall surface, the flames must pass through a flame-retardant zone of corresponding width before continuing to spread upwards along the combustible insulation material, thus slowing the upward spread of the flames and high temperatures along the exterior wall insulation system.

[0059] Composite firebreaks are installed every five floors along the building's height, creating multi-level horizontal firebreak zones on the building's exterior walls. Even if combustible insulation materials near a certain floor ignite, the composite firebreaks above can prevent the fire from spreading further.

[0060] In addition to its fire-retardant properties, the inorganic insulation board filling layer also provides thermal insulation. The thickness of the inorganic insulation board is determined based on the thickness of the adjacent existing combustible insulation layer, ensuring a smooth transition between their outer surfaces. Replacing combustible insulation materials in the corresponding area with inorganic insulation boards avoids the formation of significant horizontal thermal bridges that can occur when using ordinary cement mortar or other dense materials with high thermal conductivity.

[0061] (4) The principle of interfacial bonding, water blocking and heat insulation of composite isolation strip like Figure 2 As shown, the interface agent layer is applied to the surface of the base wall to consolidate the base layer within the construction area of ​​the composite isolation strip and improve the bonding reliability between the polymer cement waterproof slurry layer and the base wall.

[0062] The polymer cement waterproof slurry layer is applied to the outside of the interface agent layer. After curing, the polymer cement waterproof slurry forms a continuous waterproof layer, which is used to seal the capillaries, micro-cracks and construction interfaces on the surface of the base wall, reducing the penetration of external moisture into the wall along the interface between the composite isolation strip and the base wall.

[0063] The polymer cement waterproof slurry layer can also reduce the migration of moisture or water vapor along the interface between the base wall and the insulation layer, so that the composite isolation strip can form a horizontal fireproof barrier while blocking the migration path of moisture inside the external wall insulation system.

[0064] When polymer cement waterproof slurry is applied in multiple coats, each coat is applied only after the previous coat has reached a sufficiently dry state. This multi-coat application reduces the likelihood of missed areas, pinholes, or insufficient thickness in the waterproof layer, ensuring a continuous water-resistant interface.

[0065] The crack-resistant and seepage-proof composite layer is installed on the outside of the polymer cement waterproof slurry layer to protect it and serve as a transition layer between the base wall and the inorganic insulation board filling layer. When the base wall and the inorganic insulation board deform to varying degrees due to temperature changes, humidity changes, or material shrinkage, the crack-resistant and seepage-proof composite layer can buffer the corresponding deformation, reducing the possibility of micro-cracks in the base wall directly transmitting to the outer surface of the composite isolation strip.

[0066] The inorganic insulation board filling layer maintains the thermal insulation performance of the composite insulation zone from within the wall structure, while the outer waterproof and thermal insulation intermediate coating reduces the transfer of moisture and external heat from the exterior wall surface to the interior of the wall. The combination of the inorganic insulation board filling layer and the waterproof and thermal insulation intermediate coating reduces the difference in thermal performance between the composite insulation zone and the adjacent existing insulation wall surface.

[0067] (5) Crack resistance enhancement and surface restoration principle at the interface between new and old materials The inorganic insulation board filling layer and the adjacent existing combustible insulation layer may differ in density, water absorption, shrinkage rate, and temperature deformation performance. Under the influence of diurnal temperature differences, seasonal temperature differences, wind loads, and deformation of the base wall, relative deformation may occur between the inorganic insulation board filling layer and the adjacent existing combustible insulation layer, resulting in tensile or shear stress at the interface.

[0068] The triaxial fiber crack-resistant layer is applied to the outside of the inorganic insulation board's filling layer to improve the crack resistance of the inorganic insulation board surface and the interface between the inorganic insulation board and adjacent existing insulation systems. The triaxial fiber crack-resistant layer has a reinforcing structure distributed along the horizontal, vertical, and oblique directions, which can withstand and disperse tensile and shear stresses generated in different directions.

[0069] When slight relative displacement occurs at the interface between new and old materials, the triaxial fiber anti-crack layer can transfer the localized stress at the interface to the surrounding area, reducing the possibility of cracks concentrating along the edge of the inorganic insulation board and improving the integrity of the outer surface of the inorganic insulation board.

[0070] The aluminum composite layer is placed outside the triaxial fiber crack-resistant layer to cover and protect it, forming a continuous surface transition layer on the outside of the composite isolation strip. The surface restoration layer is placed outside the aluminum composite layer to level the surface of the composite isolation strip, ensuring a smooth transition between the construction area and adjacent existing walls in terms of flatness and surface texture, thus providing a flat foundation for the continuous laying of the crack-resistant stainless steel mesh.

[0071] (6) The overall reinforcement principle of crack-resistant stainless steel mesh and stainless steel anchors like Figure 2 and Figure 3As shown, after the partial repair of the wall and the construction of the fireproof, water-blocking and heat-insulating composite isolation strip are completed, a crack-resistant stainless steel mesh is continuously laid on the outside of the composite isolation strip and the repaired adjacent wall using a dry method.

[0072] The crack-resistant stainless steel mesh has a mesh size of 10mm×10mm and continuously covers the composite isolation strip, local repair areas of the wall, and adjacent existing walls. When laying, unfold and stretch the crack-resistant stainless steel mesh along the wall so that the mesh is close to the wall. Do not pre-apply bonding mortar, waterproof crack-resistant reinforcement paste, or adhesive to the inside of the crack-resistant stainless steel mesh.

[0073] After continuously covering areas of different materials with crack-resistant stainless steel mesh, the composite isolation strip, the local repair area, and the adjacent existing external wall insulation system are connected into a whole in the wall direction. When the wall is subjected to temperature changes, wind loads, or base deformation, the crack-resistant stainless steel mesh can withstand and disperse the tensile stress in the repair layer, reducing stress concentration at the edge of the composite isolation strip or the boundary of the local repair.

[0074] After the crack-resistant stainless steel mesh is unfolded and overlapped, a dust-free water drill is used to drill holes through the mesh and the existing external wall insulation system, and stainless steel anchors are installed. At least five holes and anchors are installed per square meter of wall surface, arranged in a staggered pattern. During anchor installation, the crack-resistant stainless steel mesh is directly pressed against the wall surface to prevent noticeable warping, wrinkles, or large areas of gaps.

[0075] The quincunx arrangement causes the constraint ranges corresponding to adjacent anchor points to intersect, which helps to improve the uniformity of wall stress and load transfer and reduce the formation of continuous unrestrained areas on the wall.

[0076] Select stainless steel anchors of appropriate length based on the actual thickness of the existing building's exterior wall insulation layer. The anchors should pass through the crack-resistant stainless steel mesh, the wall repair layer, and the existing exterior wall insulation system before being anchored into the base wall. The effective anchoring of the stainless steel anchors relies on the base wall, rather than on the existing insulation layer, finishing layer, or adhesive materials to fix the crack-resistant stainless steel mesh.

[0077] When the bonding performance of the existing external wall insulation layer deteriorates locally, or when the repair layer is subjected to its own weight, wind load and temperature deformation, the force can be transferred from the outer reinforcement layer to the crack-resistant stainless steel mesh, and then from the crack-resistant stainless steel mesh to the base wall through stainless steel anchors, thereby reducing the risk of hollowing, cracking or falling off of the repair layer and the existing external wall insulation layer.

[0078] (7) Waterproof and crack-resistant reinforcement layer and exterior surface protection principle like Figure 2 As shown, after the crack-resistant stainless steel mesh and stainless steel anchors are dry-laid and mechanically anchored, two coats of waterproof and crack-resistant reinforcing paste are evenly applied to their outer side to form a waterproof and crack-resistant reinforcing layer.

[0079] The first coat of waterproof and crack-resistant reinforcing compound penetrates the mesh of the crack-resistant stainless steel mesh, bonding with the surface of the composite isolation strip, the local repair layer of the wall, and the adjacent original wall surface, and also covering the crack-resistant stainless steel mesh already fixed by anchor bolts. The second coat of waterproof and crack-resistant reinforcing compound covers the mesh patterns, joints, and local weak points formed after the first coat, and completely covers the crack-resistant stainless steel mesh and stainless steel anchor bolts, ensuring that the finished wall surface has no exposed mesh or anchor bolt heads.

[0080] After the waterproof and crack-resistant reinforcing paste cures, it forms a continuous waterproof and crack-resistant reinforcing layer. This layer integrates the crack-resistant stainless steel mesh, stainless steel anchors, and the wall surface into a unified whole. It also seals the mesh openings of the stainless steel mesh, the areas around the drilled holes of the stainless steel anchors, and the small pores on the wall surface, reducing the infiltration of rainwater into the interior of the wall along the anchor points or wall cracks.

[0081] The waterproof and crack-resistant reinforcement layer can also work together with the crack-resistant stainless steel mesh to withstand the tensile stress generated by wall deformation, so that the flexible deformation capability of the waterproof and crack-resistant material and the mechanical reinforcement capability of the crack-resistant stainless steel mesh complement each other.

[0082] Apply a layer of fine-sand-type flexible crack-resistant putty to the outside of the waterproof and crack-resistant reinforcement layer. The flexible crack-resistant putty is used to fill the texture, trowel marks, and minor unevenness on the surface of the waterproof and crack-resistant reinforcement layer, to finely level the wall surface, and to buffer minor deformations of the base layer.

[0083] After the flexible crack-resistant putty reaches the appropriate construction condition, apply a coat of alkali-resistant penetrating sealant evenly to its outer surface by roller or spray. The alkali-resistant penetrating sealant is used to seal the pores of the substrate, reduce the difference in water absorption between different areas of the substrate, and reduce the outward migration of alkaline substances from the substrate.

[0084] After the alkali-resistant and penetrating sealing primer is applied, two coats of waterproof and heat-insulating intermediate coat are evenly rolled onto its outer side. The first coat of waterproof and heat-insulating intermediate coat is used to form a continuous base film layer, and the second coat is used to supplement the film layer thickness and cover any local weak points that may have been present in the first coat.

[0085] After two coats of waterproof and heat-insulating intermediate paint cure, a continuous waterproof and heat-insulating intermediate coating is formed. The waterproof and heat-insulating intermediate coating can reduce the water absorption rate of the wall surface, reduce the penetration of rainwater into the interior repair structure, and slow down the transfer of solar radiation heat into the wall.

[0086] Two coats of multi-colored paint are evenly sprayed on the outer side of the waterproof and heat-insulating intermediate coating to ensure that the construction area of ​​the composite isolation strip, the local repair area of ​​the wall, and the original wall surface are coordinated in terms of color and decorative texture.

[0087] After the multi-color paint reaches the appropriate dry state, apply a coat of water-based self-cleaning topcoat evenly by roller or spray on its outer side. The water-based self-cleaning topcoat forms the outermost protective layer of the exterior wall, which is used to improve the water resistance, weather resistance and pollution resistance of the exterior wall finish, and reduce the erosion of the inner multi-color paint layer, waterproof and heat-insulating intermediate layer and waterproof and crack-resistant reinforcement layer by the external environment.

[0088] (8) Construction process and principle of integrated action like Figure 4 As shown, the construction process of this invention includes, in sequence, wall inspection and defect marking, cutting and removing the parts to be treated, cleaning the base layer, applying the interface agent, repairing and leveling the wall, applying the fireproof, water-blocking and heat-insulating composite isolation strip, dry laying of crack-resistant stainless steel mesh, dust-free drilling and fixing of stainless steel anchors, applying waterproof and crack-resistant reinforcement paste, applying flexible crack-resistant putty, applying alkali-resistant penetrating sealing primer, applying waterproof and heat-insulating intermediate coat, applying multi-color coating, and applying water-based self-cleaning topcoat.

[0089] The triaxial fiber anti-crack layer is used to improve the crack resistance of the inorganic insulation board infill layer and the interface between new and old materials. The anti-crack stainless steel mesh is laid using a dry method and is used to enhance the integrity of the repaired wall surface. Stainless steel anchors are used to directly anchor the anti-crack stainless steel mesh and the outer repair structure to the base wall. Through the combination of internal reinforcement of the composite isolation strip, overall wall surface reinforcement and mechanical anchoring of the base layer, the composite isolation strip and adjacent repaired wall surfaces maintain the corresponding structural stability and service durability.

[0090] This invention employs a combination of partial removal, partial repair, horizontal installation of composite isolation strips, and overall wall reinforcement. It does not require the complete removal of the existing external wall insulation system that still has usable performance, thus reducing the amount of original insulation materials, mortar, and finishing materials to be removed, and reducing the generation of construction waste.

[0091] The interface agent, polymer cement waterproof slurry, waterproof crack-resistant reinforcement paste, waterproof and heat-insulating intermediate coating and water-based self-cleaning topcoat used in the construction can be water-based materials. Construction equipment with dust collection or dust-free functions should be used for wall cutting and drilling to reduce dust diffusion and volatile substance emissions during the construction process.

[0092] Example 1: Overall Repair and Construction of Fireproof, Waterproof, and Heat-Insulating Composite Insulation Strip (1) Construction object This embodiment selects an existing building exterior wall with combustible external wall insulation material as the construction object. The existing building exterior wall consists of a base wall, a 50mm thick existing combustible insulation layer, a crack-resistant mortar layer, and the original finishing layer. The wall surface has local hollow areas, cracks, peeling finish, and rainwater seepage, but the existing insulation layer, except for the defective areas, is still usable.

[0093] Fire-resistant, water-blocking, and heat-insulating composite isolation strips are installed horizontally on the exterior walls of existing buildings. The width of the fire-resistant, water-blocking, and heat-insulating composite isolation strips is 500mm vertically along the wall surface, and one strip is installed every five floors along the building's height.

[0094] The interface agent, polymer cement waterproof slurry, waterproof and crack-resistant reinforcing paste, waterproof and heat-insulating intermediate coating, and water-based self-cleaning topcoat used in the construction are all water-based materials. Construction equipment equipped with dust collection devices was used for wall cutting and drilling.

[0095] (2) Wall inspection and defect handling The exterior walls of existing buildings are inspected using a combination of visual inspection and tapping, and areas with hollow spots, cracks, peeling finishes, and areas to be removed are marked.

[0096] Use cutting equipment to cut along the edge of the area to be removed, and then remove any hollow, cracked, or poorly bonded finishing layers, crack-resistant layers, and insulation materials. When the defects extend into the insulation layer or the base layer interface, remove the corresponding portion down to the base wall.

[0097] After the initial removal, use a brush and vacuum cleaner to remove loose dust, debris, and particles from the surface of the base layer. Apply a uniform coat of two-component interface agent to the cleaned wall surface to be repaired, using 0.15-0.25 kg / m² of interface agent per unit area. 2 .

[0098] After the two-component interface agent meets the conditions for subsequent construction, the removed areas are repaired. Areas where the original wall surface contained thermal insulation mortar are filled with thermal insulation mortar, while areas where the original wall surface was a crack-resistant mortar layer are leveled with crack-resistant mortar, ensuring that the repaired area is not higher than the adjacent original wall surface.

[0099] (3) Formation of the construction area of ​​the composite isolation zone The upper and lower boundary lines of the composite isolation zone are marked on the exterior wall of the existing building according to the set position, and the distance between the upper and lower boundary lines is 500mm.

[0100] Horizontal cuts are made along the upper and lower boundary lines to remove the original finishing layer, crack-resistant layer, and combustible insulation material between the two boundary lines down to the base wall, forming a strip-shaped construction area that extends continuously along the horizontal direction of the building's exterior wall.

[0101] Remove any remaining insulation material, dust, and debris from the strip construction area, and level the upper and lower edges of the strip construction area and the surface of the base wall.

[0102] (4) Construction of interface agent layer and polymer cement waterproof slurry layer Apply a single coat of two-component interface agent evenly by roller or brush to the surface of the base wall within the strip construction area to form an interface agent layer. The unit area dosage of the interface agent is 0.15-0.25 kg / m². 2 .

[0103] After the interface agent layer is surface dry, apply a two-component polymer cement waterproof slurry to its outer side. The polymer cement waterproof slurry is applied in two cross-coats. The thickness of the first coat is 0.8-1.0 mm. After the first coat is surface dry, apply the second coat, which is also 0.8-1.0 mm thick.

[0104] Two coats of polymer cement waterproofing slurry are applied to form a polymer cement waterproofing slurry layer with a total thickness of 1.6-2.0 mm. The polymer cement waterproofing slurry continuously covers the surface of the base wall within the strip construction area, and also covers the upper and lower sidewalls of the strip construction area.

[0105] (5) Construction of crack-resistant and seepage-proof composite layer After the polymer cement waterproof slurry layer meets the conditions for subsequent construction, polymer crack-resistant and seepage-proof mortar is applied to its outer side to form a crack-resistant and seepage-proof composite layer.

[0106] The thickness of the crack-resistant and seepage-proof composite layer is 3-4mm. During construction, the polymer crack-resistant and seepage-proof mortar is compacted and leveled to ensure a continuous bond between the crack-resistant and seepage-proof composite layer and the polymer cement waterproof slurry layer.

[0107] (6) Inorganic insulation board embedding construction This embodiment uses an inorganic insulation board with a thickness of 50mm, which is compatible with the thickness of the existing combustible insulation layer.

[0108] The inorganic insulation boards are cut to size according to the actual dimensions of the strip construction area, and then embedded horizontally along the exterior wall of the building into the strip construction area. Adjacent inorganic insulation boards are arranged closely together, with a gap width of no more than 3mm.

[0109] After the inorganic insulation board is installed, the height difference between its outer surface and the outer surface of the adjacent existing combustible insulation layer should not exceed 2mm. When the local height difference exceeds 2mm, the surface of the inorganic insulation board should be polished or local leveling should be performed using crack-resistant mortar.

[0110] Inorganic insulation boards replace the removed combustible insulation materials within the composite isolation zone, thereby interrupting the continuous distribution of the existing combustible insulation layer along the building height at the location of the composite isolation zone.

[0111] (7) Construction of triaxial fiber anti-cracking layer Apply the first layer of polymer crack-resistant mortar to the outside of the inorganic insulation board, and lay a triaxial fiber reinforced mesh while the polymer crack-resistant mortar is wet.

[0112] The triaxial fiber-reinforced mesh comprises reinforcing fiber bundles distributed along the horizontal, vertical, and diagonal directions, with a unit area mass of 180-240 g / m². 2 .

[0113] The triaxial fiber reinforced mesh covers the outer surface of the inorganic insulation board and extends beyond the upper and lower boundaries between the inorganic insulation board and the adjacent existing combustible insulation layer. The extension width of the triaxial fiber reinforced mesh on the outer side of the upper and lower boundaries is 100-150mm, and the overlap width between adjacent triaxial fiber reinforced meshes is not less than 100mm.

[0114] After the triaxial fiber reinforced mesh is laid, polymer anti-cracking mortar is applied to its outer side to embed the triaxial fiber reinforced mesh inside the polymer anti-cracking mortar, forming a triaxial fiber anti-cracking layer with a total thickness of 3-5mm.

[0115] (8) Construction of aluminum composite layer and decorative restoration layer After the three-dimensional fiber anti-cracking layer meets the construction conditions, an aluminum-adhesive composite layer is laid on its outer side. The aluminum-adhesive composite layer is formed by combining aluminum foil, alkali-resistant glass fiber cloth and water-based weather-resistant adhesive, and its total thickness is 0.3-0.6 mm.

[0116] The aluminum-plastic composite layer is laid continuously along the horizontal direction of the composite isolation strip, with an overlap width of 50-80mm between adjacent aluminum-plastic composite materials. During the laying process, the aluminum-plastic composite layer is compacted to avoid the formation of air bubbles, curling edges, or obvious wrinkles.

[0117] Apply a 2-3mm thick layer of polymer repair mortar to the outside of the aluminum composite layer to form a surface restoration layer. The outer surface of the surface restoration layer should smoothly connect with the adjacent existing wall surface.

[0118] (9) Dry-hanging installation of crack-resistant stainless steel mesh A crack-resistant stainless steel mesh was laid dry on the exterior wall surface after the composite isolation strip and partial wall repairs were completed.

[0119] This embodiment uses 304 stainless steel mesh with a mesh size of 10mm×10mm and a wire diameter of 0.7mm. The crack-resistant stainless steel mesh continuously covers the composite isolation strip, the local repair areas of the wall, and the adjacent existing wall.

[0120] During the installation process, no bonding mortar, waterproof crack-resistant reinforcement paste, or adhesive is applied between the crack-resistant stainless steel mesh and the wall. Instead, the crack-resistant stainless steel mesh is directly unfolded and stretched along the wall so that the mesh adheres to the wall and is then fixed by the stainless steel anchors installed later.

[0121] The overlap width between adjacent crack-resistant stainless steel meshes is 100mm. At inside and outside corners, the crack-resistant stainless steel mesh is continuously installed along the corner of the wall; when two pieces of crack-resistant stainless steel mesh are overlapped, the overlap width on both sides of the corner is not less than 100mm.

[0122] The crack-resistant stainless steel mesh should be laid out and anchored from the center outwards to prevent shifting during installation. After laying and anchoring, the crack-resistant stainless steel mesh should be flush against the wall without any noticeable curling, wrinkles, or large areas of gaps.

[0123] (10) Drilling and stainless steel anchor construction After the crack-resistant stainless steel mesh is unfolded and overlapped on the wall, a dust-free water drill is used to drill through the crack-resistant stainless steel mesh and the existing external wall insulation system.

[0124] In this embodiment, six holes are drilled per square meter of wall surface, arranged in a quincunx pattern. The drilling locations cover the middle, overlapping, and edge areas of the crack-resistant stainless steel mesh, as well as the corners of the wall. 100mm long stainless steel anchors are selected based on the thickness of the existing external wall insulation layer.

[0125] The stainless steel anchor bolt passes through the crack-resistant stainless steel mesh, the wall repair layer, and the existing external wall insulation system before being anchored into the base wall. Its effective anchoring depth into the base wall is 30mm.

[0126] During the installation of stainless steel anchors, the crack-resistant stainless steel mesh is directly pressed against the wall surface. After the anchors are installed, the crack-resistant stainless steel mesh is mechanically fixed by the stainless steel anchors, and the anchor heads do not loosen or protrude significantly. The crack-resistant stainless steel mesh does not rely on mortar or adhesive materials for initial fixation.

[0127] (11) Construction of waterproof and crack-resistant reinforcement layer After completing the dry laying of the crack-resistant stainless steel mesh and the mechanical fixing of the stainless steel anchors, apply two coats of waterproof crack-resistant reinforcing paste to the outside of the crack-resistant stainless steel mesh and stainless steel anchors.

[0128] The first coat of waterproof and crack-resistant reinforcing compound should be 1.5-2.0mm thick, allowing it to pass through the mesh of the crack-resistant stainless steel mesh and bond with the inner wall surface. At the same time, it should cover the crack-resistant stainless steel mesh and stainless steel anchors that have already been fixed by stainless steel anchors.

[0129] After the first coat meets the requirements for subsequent construction, apply a second coat of waterproof and crack-resistant reinforcing compound, with a thickness of 1.0-1.5mm. The two coats together form a waterproof and crack-resistant reinforcing layer with a total thickness of 2.5-3.5mm.

[0130] After the waterproof and crack-resistant reinforcement layer is completed, the crack-resistant stainless steel mesh and stainless steel anchors are completely covered, and the mesh and anchor heads are not exposed on the wall.

[0131] (12) Waterproof and heat-insulating finishing construction After the waterproof and crack-resistant reinforcement layer dries, apply a layer of fine sand-type flexible crack-resistant putty to its outer side. The thickness of the flexible crack-resistant putty should be 1.0-1.5mm.

[0132] After the flexible crack-resistant putty reaches the required application conditions, apply one coat of alkali-resistant penetrating sealant primer by roller or spray. The dosage of the alkali-resistant penetrating sealant primer per unit area is 0.10-0.15 kg / m². 2 .

[0133] After the alkali-resistant and penetrating sealing primer dries, apply two coats of waterproof and heat-insulating intermediate coat by roller. The unit area application rate of each coat of waterproof and heat-insulating intermediate coat is 0.20-0.30 kg / m². 2 The two coats are applied in directions that intersect each other.

[0134] After the waterproof and heat-insulating intermediate coating meets the construction conditions, spray two coats of multi-color paint on its outer side. After the multi-color paint is fully dry, apply one coat of water-based self-cleaning topcoat by roller or spray. The unit area usage of the water-based self-cleaning topcoat is 0.10-0.15 kg / m². 2 .

[0135] After construction is completed, natural curing should be carried out, and direct rainwater erosion and external impact should be avoided during the curing period.

[0136] Comparative Example 1: Conventional repairs without fireproof, water-blocking, and heat-insulating composite isolation strips Comparative Example 1 uses the same existing building exterior wall or exterior wall specimen with the same structure as Example 1.

[0137] Comparative Example 1 involves inspecting the wall surface, cutting and removing defective parts, cleaning the base layer, applying the interface agent, repairing the thermal insulation mortar, and leveling with crack-resistant mortar, but without setting a fireproof, water-blocking, and heat-insulating composite isolation strip in the existing combustible insulation layer.

[0138] After the wall repair is completed, lay ordinary alkali-resistant fiberglass mesh directly on the outside of the wall, and then apply ordinary crack-resistant mortar, flexible putty, sealing primer, multi-color paint and topcoat in sequence.

[0139] Comparative Example 1 does not include the inorganic insulation board filling layer, polymer cement waterproof slurry layer, triaxial fiber crack-resistant layer, crack-resistant stainless steel mesh, and stainless steel anchors.

[0140] Example 1 and Comparative Example 1 were compared to evaluate the role of the fireproof, water-blocking and heat-insulating composite isolation strip in blocking the continuous distribution of combustible insulation materials, preventing the fire from spreading upward along the outer wall, and maintaining the insulation performance of the isolation strip area.

[0141] Comparative Example 2: A water-blocking barrier was installed, but no overall water-resistant anchoring structure was used. Comparative Example 2 uses the same existing building exterior wall or exterior wall specimen with the same structure as Example 1.

[0142] Comparative Example 2 also establishes a 500mm wide strip along the horizontal direction of the building's exterior wall, and removes the combustible insulation material within the strip down to the base wall. Inorganic insulation boards of the same thickness as the existing combustible insulation layer are then embedded within the strip.

[0143] Unlike Example 1, Comparative Example 2 uses only ordinary bonding mortar between the inorganic insulation board and the base wall, without setting a polymer cement waterproof slurry layer and a crack-resistant and seepage-proof composite layer; the outer side of the inorganic insulation board is only laid with ordinary alkali-resistant glass fiber mesh, without setting a triaxial fiber crack-resistant layer, an aluminum-plastic composite layer and a crack-resistant stainless steel mesh.

[0144] Comparative Example 2 does not use stainless steel anchors to anchor the wall repair structure to the base wall. Instead, ordinary crack-resistant mortar, flexible putty, sealing primer, waterproof intermediate coat, multi-color paint and topcoat are applied sequentially on the outside of ordinary alkali-resistant fiberglass mesh.

[0145] Example 1 and Comparative Example 2 were compared to evaluate the effects of polymer cement waterproof slurry layer, crack-resistant and seepage-proof composite layer, triaxial fiber crack-resistant layer, crack-resistant stainless steel mesh and stainless steel anchors on the water-blocking, crack-resistant and overall reinforcement performance of the composite isolation strip.

[0146] Performance testing and comparison (1) Specimen setup In Example 1, Comparative Example 1, and Comparative Example 2, at least three sets of exterior wall specimens of the same size were prepared. Each set of specimens used the same base wall material, existing combustible insulation material, original insulation layer thickness, and curing conditions.

[0147] Apart from the differences in the technical features that need to be compared, the construction environment, curing time and testing conditions of each group of specimens are kept consistent.

[0148] (2) Testing items After the prescribed curing was completed, the fire resistance, waterproof performance, heat insulation performance, crack resistance and mechanical reinforcement performance of Example 1, Comparative Example 1 and Comparative Example 2 were tested.

[0149] Fire resistance can be evaluated by the flame spread height, the temperature rise on the unexposed side, or whether the combustible insulation material above the composite isolation strip continues to burn.

[0150] Waterproof performance can be evaluated by the amount of water absorbed per unit area, whether water seepage occurs on the back after continuous water spraying, the area of ​​water seepage, and the change in the moisture content of the wall.

[0151] Thermal insulation performance can be evaluated by measuring the temperature rise or heat flux density on the back side of the specimen under the same heat source and heating time conditions.

[0152] Crack resistance can be evaluated under the same thermal cycling, freeze-thaw cycling, or wet-dry cycling conditions by the maximum crack width, the number of cracks, and whether hollow areas occur.

[0153] Mechanical reinforcement performance can be evaluated by the tensile bond strength of the wall surface, the pull-out bearing capacity of the stainless steel anchors, and the extent of localized wall detachment.

[0154] Horizontal isolation zone Setting the width to 500mm Not set Setting the width to 500mm Inorganic insulation board set up Not set set up Polymer cement waterproof slurry layer set up Not set Not set Crack-resistant and seepage-proof composite layer set up Not set Not set Triaxial fiber crack-resistant layer set up Not set Not set Aluminum-coated composite layer set up Not set Not set Crack-resistant stainless steel mesh Setting up, dry laying Ordinary alkali-resistant fiberglass mesh Ordinary alkali-resistant fiberglass mesh Stainless steel anchors <![CDATA[Setting, 6 pieces / m 2 , directly fix the stainless steel mesh]]> Not set Not set Waterproof and crack-resistant reinforcing paste Twice Ordinary crack-resistant mortar Ordinary crack-resistant mortar Waterproof and heat-insulating intermediate coating Twice No setting or ordinary intermediate coating set up Water-based self-cleaning paint Once ordinary topcoat ordinary topcoat Flame spread height mm 680 2480 910 Is there ongoing burning above the firebreak? — no yes no Area of ​​water seepage on the back after continuous watering cm2 0 138 36 24-hour water absorption per unit area <![CDATA[kg / m 2 ]]> 0.21 1.16 0.62 Back side temperature rise under the same heating conditions ℃ 18.6 35.4 22.8 Maximum crack width after thermal cycling mm 0.06 0.44 0.23 Number of cracks after thermal cycling strip / m2 0.3 4.7 2.3 Tensile bond strength MPa 1.31 0.25 0.34 Anchor bolt single-point pull-out bearing capacity kN 1.74 not applicable not applicable Does hollowness or localized detachment occur? — no Localized hollowing and small areas of detachment occurred. Localized hollow areas were observed, but the product did not detach. The results in the table show that, under the same base wall, original insulation layer thickness, construction environment, curing time, and testing conditions, the flame spread height of Example 1 was 680 mm, significantly lower than that of Comparative Example 1 (2480 mm) and Comparative Example 2 (910 mm). Furthermore, no sustained combustion occurred above the composite isolation strip in Example 1. These results indicate that the continuously installed inorganic insulation board filling layer can interrupt the continuous distribution of combustible insulation material along the wall height and block the upward spread of flames.

[0155] Comparative Example 2 also uses inorganic insulation boards, so no continuous combustion occurred above its composite isolation strip. However, due to the absence of polymer cement waterproof slurry layer, crack-resistant and seepage-proof composite layer, triaxial fiber crack-resistant layer, and crack-resistant stainless steel mesh anchoring structure, its flame spread height is still greater than that of Example 1. This indicates that the continuous and stable connection of each material layer of the composite isolation strip is beneficial to maintaining the integrity of the isolation strip structure.

[0156] After continuous water spraying, no measurable seepage area appeared on the back of Example 1, and the water absorption per unit area in 24 hours was 0.21 kg / m². 2 The back surface area of ​​Comparative Example 1 with water seepage is 138 cm². 2 The water absorption rate per unit area in 24 hours is 1.16 kg / m². 2 The back surface of Comparative Example 2 has a water seepage area of ​​36 cm². 2 The water absorption rate per unit area in 24 hours is 0.62 kg / m². 2 The above results indicate that the polymer cement waterproof slurry layer, the waterproof and crack-resistant reinforcement layer, and the waterproof and heat-insulating finishing layer can respectively seal the water penetration path from the inside of the composite isolation zone and the outside of the wall.

[0157] Under the same heating conditions, the back temperature rise of Example 1 was 18.6°C, which was lower than that of Comparative Example 1 (35.4°C) and Comparative Example 2 (22.8°C). This indicates that the inorganic insulation board filling layer can maintain the thermal insulation performance of the isolation zone while forming a fireproof partition. The polymer waterproof structure and the outer waterproof and thermal insulation coating can further reduce the transfer of moisture and heat to the interior of the wall.

[0158] After the thermal cycling test, the maximum crack width in Example 1 was 0.06 mm, and the number of cracks was 0.3 / m. 2 No hollow areas or localized detachment were observed; in Comparative Example 1, the maximum crack width was 0.44 mm, and the number of cracks was 4.7 / m. 2 In contrast, localized hollowing and small-area detachment were observed; in Comparative Example 2, the maximum crack width was 0.23 mm, and the number of cracks was 2.3 / m. 2 Furthermore, localized hollow areas appeared. The above results indicate that the triaxial fiber crack-resistant layer can disperse the stress at the interface between the inorganic insulation board and the original combustible insulation layer. The dry-laid crack-resistant stainless steel mesh can establish a stable mechanical connection with the base wall through stainless steel anchors without relying on wet bonding, thereby improving the overall crack resistance of the repaired wall surface.

[0159] In Example 1, the tensile bond strength was 1.31 MPa, and the single-point pull-out bearing capacity of the stainless steel anchor was 1.74 kN, both of which maintained a stable wall connection. The crack-resistant stainless steel mesh was laid using a dry method and directly anchored to the base wall using six stainless steel anchors arranged in a quincunx pattern per square meter. This allowed the self-weight, wind load, and temperature deformation borne by the external repair structure to be transferred to the base wall through the crack-resistant stainless steel mesh and stainless steel anchors, reducing the risk of hollowing, cracking, and detachment of the existing external wall insulation system.

[0160] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0161] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0162] The above description is merely 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.

Claims

1. A fireproof, water-blocking, and heat-insulating composite insulation strip for the exterior walls of existing buildings, installed in the combustible insulation layer on the outside of the base wall, characterized in that: The combustible insulation layer has a horizontally continuous break strip that extends through its thickness. The break strip is filled with an inorganic insulation board with an inorganic material matrix and a combustion performance rating of not less than A2. A polymer cement waterproof bonding layer is continuously provided between the inorganic insulation board and the base wall and the upper and lower sidewalls of the break strip, and a triaxial fiber crack-resistant layer is provided on the outer side of the inorganic insulation board that crosses its upper and lower boundaries. The composite isolation strip and its adjacent outer side are continuously provided with crack-resistant stainless steel mesh. There is no bonding mortar layer or adhesive layer between the crack-resistant stainless steel mesh and the wall. The crack-resistant stainless steel mesh is directly anchored to the base wall by anchor bolts that pass through the existing external wall insulation system. A waterproof crack-resistant reinforcement layer and a waterproof heat insulation finishing layer are provided in sequence on the outer side of the crack-resistant stainless steel mesh.

2. The fireproof, water-blocking, and heat-insulating composite insulation strip for the exterior walls of existing buildings according to claim 1, characterized in that: The width of the break strip along the vertical direction of the wall is 500mm, and the composite isolation strip is set every five floors along the building height direction; the inorganic insulation board completely replaces the combustible insulation layer in the break strip along the wall thickness direction.

3. The fireproof, water-blocking, and heat-insulating composite insulation strip for the exterior walls of existing buildings according to claim 1, characterized in that: The inorganic insulation board is an insulation board with inorganic material as the matrix and no halogenated flame retardant is added to achieve fire resistance. Its combustion performance rating is not lower than A2, its density is 120-350 kg / m³, its thermal conductivity is not greater than 0.070 W / (m·K), and its volume water absorption rate is not greater than 5%. The thickness of the inorganic insulation board is not more than 2 mm different from the thickness of the adjacent combustible insulation layer, and the height difference between its outer surface and the outer surface of the adjacent combustible insulation layer is not more than 2 mm.

4. The fireproof, water-blocking, and heat-insulating composite insulation strip for the exterior walls of existing buildings according to claim 1, characterized in that: The polymer cement waterproof bonding layer includes a two-component interface agent layer disposed on the surface of the base wall and a polymer cement waterproof slurry layer disposed on the outside of the two-component interface agent layer; the polymer cement waterproof slurry layer continuously covers the base wall and the upper and lower sidewalls of the break zone, with a total thickness of 1.5-2.5mm, and extends 50-100mm to the outside of the upper and lower boundaries of the break zone respectively.

5. The fireproof, water-blocking, and heat-insulating composite insulation strip for the exterior walls of existing buildings according to claim 1, characterized in that: The triaxial fiber crack-resistant layer comprises a polymer crack-resistant and seepage-proof mortar layer with a thickness of 3-5 mm and a triaxial fiber reinforcing mesh embedded within the polymer crack-resistant and seepage-proof mortar layer; the triaxial fiber reinforcing mesh has longitudinal, transverse, and oblique reinforcing fiber bundles, with a unit area mass of 180-300 g / m². 2 Its upper and lower edges extend beyond the upper and lower boundaries of the inorganic insulation board and overlap the outer side of the adjacent combustible insulation layer, with an overlap width of 100-150mm.

6. The fireproof, water-blocking, and heat-insulating composite insulation strip for the exterior walls of existing buildings according to claim 5, characterized in that: An aluminum-coated composite layer is provided on the outside of the triaxial fiber anti-cracking layer. The aluminum-coated composite layer is formed by bonding aluminum foil and alkali-resistant glass fiber cloth with weather-resistant adhesive, and its thickness is 0.2-0.8mm. A surface restoration layer that connects with the existing exterior wall finish is provided on the outside of the aluminum-coated composite layer.

7. The fireproof, water-blocking, and heat-insulating composite insulation strip for the exterior walls of existing buildings according to claim 4, characterized in that: The waterproof and crack-resistant reinforcement layer is formed by waterproof and crack-resistant reinforcement paste, and the waterproof and heat-insulating finishing layer includes a waterproof and heat-insulating intermediate coating layer and a water-based self-cleaning topcoat layer; the two-component interface agent, polymer cement waterproof slurry, waterproof and crack-resistant reinforcement paste, waterproof and heat-insulating intermediate coating and water-based self-cleaning topcoat are all water-based materials. The thickness of the waterproof and crack-resistant reinforcement layer is 2-4mm, and the waterproof and heat-insulating intermediate coating is formed by two coats of waterproof and heat-insulating intermediate paint, which continuously covers the composite isolation strip and the adjacent wall surface.

8. A construction method for a fireproof, water-blocking, and heat-insulating composite isolation strip for the exterior walls of existing buildings, characterized in that, Includes the following steps: S1. Inspect the exterior walls of existing buildings and mark areas with hollow spots, cracks and areas to be removed. Cut and remove the areas to be removed down to the base wall, remove loose dust and debris, and perform interface treatment and repair leveling on the wall surface. S2. In the combustible insulation layer, a 500mm wide, continuous strip is formed horizontally every five floors. S3. Apply a two-component interface agent and polymer cement waterproof slurry to the surface of the base wall and the upper and lower side walls of the disconnected zone to form a continuous polymer cement waterproof bonding layer. S4. An inorganic insulation board with an inorganic material matrix and a fire performance rating of not less than A2 is embedded in the break strip, so that the inorganic insulation board completely replaces the combustible insulation layer in the break strip along the wall thickness direction, and the thickness difference and the outer surface height difference between the inorganic insulation board and the adjacent combustible insulation layer do not exceed 2mm. S5. Apply polymer crack-resistant and seepage-proof mortar to the outside of the inorganic insulation board, and lay a triaxial fiber reinforced mesh that spans the upper and lower boundaries of the inorganic insulation board. Then apply the aluminum composite layer and the decorative restoration layer. S6. Dry-lay anti-crack stainless steel mesh continuously on the outside of the composite isolation strip and adjacent wall surface, so that the anti-crack stainless steel mesh is unfolded and attached to the wall surface, without pre-applying adhesive mortar or adhesive material between the anti-crack stainless steel mesh and the wall surface; use a dust-free water drill to drill through the anti-crack stainless steel mesh and the existing external wall insulation system, and anchor the anti-crack stainless steel mesh directly to the base wall through anchor bolts. S7. Construct a waterproof and crack-resistant reinforcement layer on the outside of the crack-resistant stainless steel mesh and anchor bolts, and construct a waterproof and heat-insulating finishing layer on the outside of the waterproof and crack-resistant reinforcement layer.

9. The construction method according to claim 8, characterized in that: In step S3, the polymer cement waterproof slurry is applied in two cross-coats, with each coat having a thickness of 0.75-1.25mm. The second coat is applied after the first coat has dried to the touch. The polymer cement waterproof slurry continuously covers the base wall and the upper and lower sidewalls of the break zone, extending 50-100mm beyond the upper and lower boundaries of the break zone. In step S5, the triaxial fiber reinforced mesh is embedded in the middle of the polymer crack-resistant and seepage-proof mortar, with an overlap width of 100-150mm at its upper and lower edges.

10. The construction method according to claim 8, characterized in that: In step S6, 304 stainless steel mesh with a mesh size of 10mm×10mm and a wire diameter of 0.6-0.9mm is used. The crack-resistant stainless steel mesh is laid using a dry method, with adjacent crack-resistant stainless steel meshes overlapping by 100-150mm. Holes are drilled using a dust-free water drill, and anchor bolts are distributed in a quincunx pattern at 5-8 per square meter. The crack-resistant stainless steel mesh is directly pressed and fixed to the wall surface, and the effective anchoring depth of the anchor bolts is 25-50mm. In step S7, a waterproof crack-resistant reinforcing paste with a total thickness of 2-4mm is applied in two coats. Subsequently, fine sand-type flexible crack-resistant putty for exterior walls, alkali-resistant penetrating sealing primer, waterproof and heat-insulating intermediate coat, multi-color paint, and water-based self-cleaning topcoat are applied in sequence.

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