A construction method to prevent moisture and alkali efflux at the base of GRC curtain wall panels

Abstract

The present invention specifically relates to a construction method for preventing moisture and alkali efflux at the root of a GRC curtain wall panel, which solves the problem that the two existing methods for solving moisture and alkali efflux at the root of a GRC curtain wall panel are high in cost and not durable. A construction method for preventing moisture and alkali efflux at the root of a GRC curtain wall panel, step S1: casting a U-shaped trough; step S2: installing a main exhaust pipe; step S4: making a cover assembly; step S5: fixing the cover assembly; step S6: installing a GRC curtain wall panel; step S7: casting a diffuser layer. The present invention fundamentally solves the moisture and alkali efflux problems of the GRC curtain wall panel; the silicone weather-resistant sealant layer and the SBS waterproof membrane layer 7 are used for sealing, thereby blocking the upward path of moisture on the GRC curtain wall panel. The construction method performs waterproofing or ventilation measures on the outside, inside, and root of the GRC curtain wall panel, respectively, and the blocking time is long, and no cleaning and maintenance by operators is required, thereby reducing costs.

Description

Technical Field

[0001] The invention relates to the technical field of building engineering, in particular to a construction method for preventing moisture and alkali efflorescence at the root of a GRC curtain wall panel. Background Art

[0002] GRC curtain wall panels have the advantages of being light in weight and extremely strong, and have certain fire resistance and good ductility. Currently, GRC curtain wall panels have been widely used in the entire construction industry, especially as decoration and insulation for the exterior walls of buildings.

[0003] During the construction of GRC curtain wall panels, they are installed from the top of the building's exterior wall to the outdoor green floor. The moisture under the green floor will rise along the capillary channels in the GRC curtain wall panels and evaporate from the surface of the GRC curtain wall panels. The soluble salts and alkalis in the soil and the GRC curtain wall panels will dissolve into the moisture. When the moisture evaporates, the dissolved salts and alkalis will crystallize on the surface and near the surface of the GRC curtain wall panels. When crystallizing, their volume expands slightly, and white crystals will form on the surface and near the surface of the GRC curtain wall panels, causing the GRC curtain wall panels to change color. In severe cases, the GRC curtain wall panels will become loose and eventually peel off layer by layer, seriously affecting the durability and quality of the GRC curtain wall panels.

[0004] Based on the above situation, the following two methods are usually used to solve the problem of moisture and alkali efflux at the root of GRC curtain wall panels: one is to use oxalic acid and acetic acid solutions to clean and decontaminate the GRC curtain wall surface, or directly replace the GRC curtain wall panels. This method has a large workload and high labor costs, and cannot fundamentally solve the problem; the second is to fill asphalt sealant and apply waterproof mortar and other moisture-proof layers between the scattered water and the GRC curtain wall panels to block the upward penetration of moisture from the green floor. This method is not long-lasting, especially in humid and rainy, cold and humid environments, which can easily lead to the failure of the moisture-proof layer.

[0005] Therefore, it is necessary to invent a construction method to prevent moisture and alkali efflux at the root of the GRC curtain wall panel to solve the above problems. Summary of the invention

[0006] In order to solve the problems of high cost and lack of durability of two existing methods for solving moisture and alkali efflorescence at the root of GRC curtain wall panels, the present invention provides a construction method for preventing moisture and alkali efflorescence at the root of GRC curtain wall panels.

[0007] The present invention is achieved by adopting the following technical solutions:

[0008] A construction method for preventing moisture and alkali efflorescence at the root of a GRC curtain wall panel is implemented by the following steps:

[0009] Step S1: Cast a U-shaped trough with the notch facing upward and arranged longitudinally on the outer side of the root of the foundation wall, and the end of the U-shaped trough extends to the inside of the greening floor, and the surface of the greening floor is provided with an exhaust pipe channel arranged vertically and connected to the U-shaped trough;

[0010] Step S2: installing curtain wall panel keels on the outer side of the foundation wall, and the curtain wall panel keels are located above the U-shaped trough;

[0011] Step S3: installing a main exhaust pipe arranged longitudinally in the inner cavity of the U-shaped trough body, and the end of the main exhaust pipe extends out of the exhaust pipe channel;

[0012] Step S4: making a cover plate assembly; the cover plate assembly comprises a cover plate matching the size of the U-shaped trough body, an SBS waterproofing membrane layer is fixed on the lower side of the cover plate, and the width of the SBS waterproofing membrane layer is greater than the width of the cover plate; a plurality of exhaust pipes arranged vertically and evenly distributed along the front and back are penetrated on the cover plate and the SBS waterproofing membrane layer;

[0013] Step S5: coating the upper surface of the U-shaped trough with a silicone weatherproof sealant layer, and bonding and fixing the cover plate assembly to the silicone weatherproof sealant layer, while connecting each exhaust pipe to the main exhaust pipe;

[0014] Step S6: Apply a silicone weatherproof sealant layer I between the cover plate and the curtain wall panel keel, and after the application is completed, install the GRC curtain wall panel at the bottom of the outer side of the curtain wall panel keel; then apply a silicone weatherproof sealant layer II on the outer side of the GRC curtain wall panel, and after the application is completed, fold the SBS waterproof membrane layer that exceeds the cover plate upward and bond it to the silicone weatherproof sealant layer II; at this time, the outer surface of the SBS waterproof membrane layer is flush with the side of the U-shaped trough; then complete the installation of the remaining GRC curtain wall panels;

[0015] Step S7: pouring a water dispersion layer between the SBS waterproofing membrane layer and the greening floor.

[0016] The structural design of the present invention is reasonable and reliable, and the problems of moisture regurgitation and alkali efflorescence of the GRC curtain wall panels are solved; the root of the GRC curtain wall panels is blocked by a silicone weather-resistant sealant layer, which blocks the upward extension path of moisture on the GRC curtain wall panels, and further blocks the reaction path of moisture and the GRC curtain wall panels; the addition of a hydrophobic material SBS waterproofing membrane layer can prevent the side of the GRC curtain wall panels from being eroded by moisture; the construction method takes waterproof or ventilation measures from the outside, inside and root of the GRC curtain wall panels respectively, and fundamentally solves the problems of moisture regurgitation and alkali efflorescence of the GRC curtain wall panels. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural schematic diagram of the present invention.

[0018] Figure 2 It is a side view schematic diagram of the present invention.

[0019] In the figure: 1-foundation wall, 2-U-shaped trough, 3-green floor, 4-curtain wall panel keel, 5-main exhaust pipe, 6-cover plate, 7-SBS waterproof membrane layer, 8-exhaust pipe, 9-silicone weathering sealant layer, 10-silicone weathering sealant layer I, 11-GRC curtain wall panel, 12-silicone weathering sealant layer II, 13-spreading layer, 14-observation channel, 15-sealing cover plate, 16-exhaust cap. DETAILED DESCRIPTION

[0020] GRC curtain wall panel alkali efflorescence principle: Since the GRC curtain wall panel contains quicklime, it reacts with excess water to generate slaked lime (calcium hydroxide), the reaction formula is:

[0021] CaO+H2O=Ca(OH)2

[0022] The slaked lime (calcium hydroxide) partially dissolves in water and ionizes to produce calcium ions and hydroxide ions, making the slurry alkaline. The reaction formula is:

[0023] Ca(0H)2=Ca 2 +20H 一

[0024] There are a lot of Ca(OH)2 crystals in the GRC curtain wall, accounting for about 30% to 35% of the hydration products. Ca(OH)2 dissolves and seeps out under the action of infiltrating rainwater and reacts with CO in the air. 2 Reaction, the reaction formula is:

[0025] Ca(OH)2+CO2+nH2O=CaCO3+(n+1)H2O

[0026] The generated CaCO3 adheres to the surface of the curtain wall panel and forms efflorescence phenomenon.

[0027] Based on the efflorescence principle, this construction method fundamentally blocks the upward extension of moisture, and ventilation equipment such as the main exhaust pipe 5 and the exhaust pipe 8 are set during construction to ensure that the inner side of the GRC curtain wall panel is in a ventilated and dry state; the U-shaped trough 2 and the cover plate assembly can effectively store and control underground water vapor and moisture to prevent the moisture from expanding outward; the root of the GRC curtain wall panel is sealed with a silicone weather-resistant sealant layer to block the upward extension path of moisture on the GRC curtain wall panel, thereby blocking the reaction path between moisture and the GRC curtain wall panel; the addition of a hydrophobic material SBS waterproof membrane layer 7 can prevent the side of the GRC curtain wall panel from being eroded by moisture; this construction method takes waterproof or ventilation measures from the outside, inside and root of the GRC curtain wall panel, fundamentally solving the problems of moisture regurgitation and efflorescence of the GRC curtain wall panel; and the blocking time is long, and there is no need for cleaning and maintenance by operators, which reduces costs.

[0028] A construction method to prevent moisture and alkali efflux at the root of GRC curtain wall panels, as shown in the following Figure 1 , Attachment Figure 2 As shown, the method is implemented by the following steps:

[0029] Step S1: Cast a U-shaped trough 2 with the notch facing upward and arranged longitudinally on the outer side of the root of the foundation wall 1, and the end of the U-shaped trough 2 extends to the inside of the greening floor 3, and the surface of the greening floor 3 is provided with an exhaust pipe channel arranged vertically and connected to the U-shaped trough 2;

[0030] When pouring the U-shaped trough 2, a 25 cm steel pipe welded steel plate is used as the inner formwork, and a 5 cm thick scaffolding board is used as the outer formwork; then C30P6 waterproof concrete is poured and vibrated with a small vibrator; when the concrete strength reaches more than 70%, the formwork is removed; the height of the U-shaped trough 2 is 20 cm, the ditch wall thickness is 5 cm, and the bottom plate thickness is 10 cm; and the U-shaped trough 2 extends 50 cm outside the water dispersion layer 13;

[0031] Step S2: installing a curtain wall panel keel 4 on the outer side of the basic wall 1, and the curtain wall panel keel 4 is located above the U-shaped trough 2;

[0032] When the concrete strength of the U-shaped trough 2 reaches 100%, the curtain wall panel keel 4 is installed;

[0033] Step S3: installing a main exhaust pipe 5 arranged longitudinally in the inner cavity of the U-shaped tank body 2, and an end of the main exhaust pipe 5 extends out of the exhaust pipe channel;

[0034] Step S4: making a cover plate assembly; the cover plate assembly comprises a cover plate 6 matching the size of the U-shaped trough 2, a SBS waterproofing membrane layer 7 is fixed to the lower side of the cover plate 6, and the width of the SBS waterproofing membrane layer 7 is greater than the width of the cover plate 6; a plurality of exhaust pipes 8 arranged vertically and evenly distributed front and back are provided on the cover plate 6 and the SBS waterproofing membrane layer 7;

[0035] The distance between two adjacent exhaust pipes 8 is 1m; the exhaust pipe 8 is a PVC pipe with a diameter of 5cm; the width of the SBS waterproof membrane layer 7 is equal to the width of the cover plate 6 plus the thickness of the water dispersion layer 13;

[0036] Step S5: coating the upper surface of the U-shaped trough 2 with a silicone weatherproof sealant layer 9, and bonding and fixing the cover plate assembly to the silicone weatherproof sealant layer 9, while connecting each exhaust pipe 8 with the main exhaust pipe 5;

[0037] The thickness of the silicone weatherproof sealant layer 9 is 3 cm; each exhaust pipe 8 is connected to the main exhaust pipe 5 by a three-way elbow connector;

[0038] Step S6: Apply a silicone weatherproof sealant layer I10 between the cover plate 6 and the curtain wall panel keel 4, and after the application is completed, install the GRC curtain wall panel 11 at the bottom of the outer side of the curtain wall panel keel 4; then apply a silicone weatherproof sealant layer II12 on the outer side of the GRC curtain wall panel 11, and after the application is completed, fold the SBS waterproof membrane layer 7 that exceeds the cover plate 6 upward and bond it to the silicone weatherproof sealant layer II12; at this time, the outer surface of the SBS waterproof membrane layer 7 is flush with the side of the U-shaped trough 2; then complete the installation of the remaining GRC curtain wall panels 11;

[0039] The thickness of the silicone weatherproof sealant layer I10 is 2 cm; and the junction between the foundation wall 1 and the cover plate 6 is filled with silicone weatherproof sealant to prevent moisture from penetrating;

[0040] Step S7: pouring a water dispersion layer 13 between the SBS waterproof membrane layer 7 and the greening floor 3.

[0041] The thickness of the water dispersion layer 13 is 15 cm; and the water dispersion layer 13 can also protect the SBS waterproof membrane layer 7;

[0042] As attached Figure 2 As shown, an observation channel 14 is opened on the greening floor 3 and is located directly above the U-shaped trough body 2 , and a sealing cover plate 15 is covered at the end of the observation channel 14 .

[0043] The structural design of the observation channel 14 and the sealing cover plate 15 facilitates the observation of the moisture in the inner cavity of the U-shaped trough body 2, and also facilitates the subsequent drying and discharge of the accumulated water in the inner cavity of the U-shaped trough body 2; the sealing cover plate 15 and the port of the observation channel 14 are filled with silicone weather-resistant sealant.

[0044] As attached Figure 2 As shown, an exhaust cap 16 is installed at the end of the main exhaust pipe 5.

[0045] In the description of the present invention, it is necessary to understand that the indicated orientation or positional relationship is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0046] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A construction method for preventing moisture and alkali efflorescence at the root of a GRC curtain wall panel, characterized in that: This method is implemented by the following steps: Step S1: a U-shaped trough (2) with an upward notch and arranged longitudinally is cast on the outer side surface of the root of the foundation wall (1), and the end of the U-shaped trough (2) extends to the inside of the greening floor (3), and an exhaust pipe channel arranged vertically and connected to the U-shaped trough (2) is opened on the surface of the greening floor (3); Step S2: installing a curtain wall panel keel (4) on the outer side of the foundation wall (1), and the curtain wall panel keel (4) is located above the U-shaped trough (2); Step S3: installing a main exhaust pipe (5) arranged in the longitudinal direction in the inner cavity of the U-shaped trough body (2), with the end of the main exhaust pipe (5) extending out of the exhaust pipe channel; Step S4: manufacturing a cover plate assembly; the cover plate assembly comprises a cover plate (6) having a size matching that of the U-shaped trough body (2); a SBS waterproofing coiled material layer (7) is fixed to the lower side of the cover plate (6); and the width of the SBS waterproofing coiled material layer (7) is greater than the width of the cover plate (6); and a plurality of exhaust pipes (8) are provided on the cover plate (6) and the SBS waterproofing coiled material layer (7) in a vertical direction and evenly distributed in the front and rear directions; Step S5: coating the upper surface of the U-shaped trough body (2) with a silicone weatherproof sealant layer (9), and bonding and fixing the cover plate assembly to the silicone weatherproof sealant layer (9), while connecting each exhaust pipe (8) to the main exhaust pipe (5); Step S6: a silicone weatherproof sealant layer I (10) is applied between the cover plate (6) and the curtain wall panel keel (4), and after the application is completed, a GRC curtain wall panel (11) is installed at the bottom of the outer side surface of the curtain wall panel keel (4); then a silicone weatherproof sealant layer II (12) is applied to the outer side surface of the GRC curtain wall panel (11), and after the application is completed, the SBS waterproofing membrane layer (7) that extends beyond the cover plate (6) is folded upward and bonded to the silicone weatherproof sealant layer II (12); at this time, the outer surface of the SBS waterproofing membrane layer (7) is flush with the side surface of the U-shaped trough body (2); and then the installation of the remaining GRC curtain wall panels (11) is completed; Step S7: pouring a water dispersion layer (13) between the SBS waterproofing membrane layer (7) and the greening floor (3).

2. A construction method for preventing moisture and alkali efflorescence at the root of a GRC curtain wall panel according to claim 1, characterized in that: An observation channel (14) is opened on the greening floor (3) and is located directly above the U-shaped trough body (2). The end of the observation channel (14) is covered with a sealing cover plate (15).

3. A construction method for preventing moisture and alkali efflorescence at the root of a GRC curtain wall panel according to claim 1, characterized in that: An exhaust cap (16) is installed at the end of the main exhaust pipe (5).

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