Construction concrete curing process

Abstract

The invention provides a construction concrete curing process, which relates to the technical field of building construction, and comprises the following steps: carrying out surface film forming treatment at the initial setting stage of concrete; laying a composite maintenance layer with water retention and reflection functions; the concrete humidity is monitored through an embedded humidity sensor, and humidity data is obtained; controlling a local water supplementing system to operate according to the humidity data; and dynamic temperature regulation is implemented in combination with the environment temperature. Pores in the surface of the concrete are sealed by the water-retaining film layer, so that the problem of early cracking caused by rapid evaporation of water is solved; water is evenly distributed through the composite maintenance layer, local dry-wet difference is eliminated, solar radiation is reflected, the surface temperature is lowered, and temperature stress cracks are reduced. The concrete humidity is monitored through the humidity sensor, water is supplemented according to needs, compared with regular spraying, the use amount of water resources is reduced, and the water saving effect is achieved; and the contradiction that the strength is reduced due to excessive water replenishing or shrinkage is caused due to insufficient water replenishing in traditional curing is also solved.

Description

Technical Field

[0001] The present invention relates to the technical field of building construction, and specifically relates to a construction concrete curing process. Background Art

[0002] Concrete curing is a key construction link to ensure its strength development, durability and crack resistance. Traditional curing methods mainly include natural sprinkling, covering with wet burlap or plastic film, etc. However, these methods have the following significant defects in practical applications:

[0003] Natural sprinkling curing relies on manual operation, and the water evaporation is fast. Especially in high-temperature or dry environments, it is easy to cause the concrete surface to lose water too quickly, leading to plastic shrinkage cracks; covering with wet burlap can delay water evaporation, but it requires frequent water replenishment, with high labor intensity and serious water resource waste; plastic film covering can reduce water loss, but local voids are easily formed between the film and the concrete surface, resulting in uneven curing, and the film is easily lifted or damaged by the wind, affecting the curing effect.

[0004] For mass concrete or in high-temperature environments, it is difficult for traditional methods to effectively control the temperature difference between the inside and outside of the concrete, and cracks are easily generated due to temperature stress. In the prior art, although spray cooling has a certain effect, it is easy to cause the surface water to be saturated, affecting the later strength of the concrete. Summary of the Invention

[0005] The purpose of the present invention is to provide a construction concrete curing process. The technical problem to be solved is how to achieve a water-saving, efficient, intelligent and controllable concrete curing process, regulate the temperature and humidity of the concrete under complex environmental conditions, and achieve the water-saving effect at the same time.

[0006] The present invention is achieved through the following technical solutions:

[0007] A construction concrete curing process includes the following steps:

[0008] Perform surface film-forming treatment during the initial setting stage of the concrete;

[0009] Lay a composite curing layer with water retention and reflection functions;

[0010] Monitor the humidity of the concrete through buried humidity sensors to obtain humidity data;

[0011] Control the operation of the local water replenishment system according to the above humidity data;

[0012] Implement dynamic temperature regulation in combination with the ambient temperature.

[0013] The water retention film formed in the initial setting stage can seal the fine pores on the concrete surface, reduce the water evaporation rate, effectively inhibit plastic shrinkage cracks, and solve the problem of early cracking caused by rapid water evaporation. Compared with simple water spraying curing, the film-forming agent can avoid the adverse effects of surface water saturation on the hydration reaction. By means of the composite curing layer, water is evenly distributed, local dry-wet differences are eliminated, solar radiation is reflected, the surface temperature is reduced, and temperature stress cracks are reduced. The humidity of the concrete is monitored by a humidity sensor, and water is replenished as needed, reducing the water resource consumption compared with regular spraying, achieving the effect of water conservation. It also solves the contradiction of "strength reduction caused by excessive water replenishment" or "shrinkage caused by insufficient water replenishment" in traditional curing. By the ambient temperature, atomized spraying is carried out during high-temperature periods to reduce the concrete surface temperature and control the temperature difference between the inside and outside of the concrete.

[0014] Further, the above surface film-forming treatment uses an acrylic-based film-forming agent, and the spraying amount is 0.1 - 0.2 kg / m², forming a water retention film layer with a thickness of 0.05 - 0.1 mm.

[0015] Further, 1 - 3 wt% of nano-silica particles with a particle size of 20 - 50 nm are added to the above acrylic-based film-forming agent.

[0016] Further, the above composite curing layer includes a water-absorbent non-woven fabric layer and a reflective aluminum foil film layer.

[0017] The above water-absorbent non-woven fabric layer directly contacts the concrete surface, and the weight of the water-absorbent non-woven fabric layer per square meter is greater than or equal to 200 g.

[0018] The above reflective aluminum foil film layer covers the upper surface of the water-absorbent non-woven fabric layer, and the reflectivity of the reflective aluminum foil film layer is greater than or equal to 85%.

[0019] Further, magnetic fixing strips are arranged at the edges of the above reflective aluminum foil film, and the above reflective aluminum foil film is connected to the embedded parts pre-buried in the concrete through the magnetic fixing strips.

[0020] Further, the above humidity sensors are arranged in a matrix, and the distance between adjacent humidity sensors is less than 2 m; the monitoring depth of the above humidity sensors is 10 - 15 mm.

[0021] Further, the above local water replenishment system includes:

[0022] A microporous water permeable pipe arranged in the composite curing layer, and the aperture of the above microporous water permeable pipe is 0.1 - 0.3 mm.

[0023] When any one of the above humidity sensors detects that the humidity is lower than 90%, the microporous water permeable pipe in the corresponding area of the humidity sensor is started to replenish water.

[0024] Further, the above dynamic temperature regulation includes:

[0025] When the above environmental temperature is greater than 30°C, start the atomizing spray system at a preset time period every day;

[0026] Arrange phase change material capsules in the above composite curing layer, and load phase change materials in the above phase change material capsules;

[0027] The phase change temperature of the above phase change material capsules is 28 - 32°C.

[0028] Furthermore, it also includes a curing quality monitoring step, which monitors the internal stress data of the concrete through buried optical fiber sensors, and dynamically adjusts the curing period according to the stress data.

[0029] Furthermore, the above curing period is 14 - 28 days, and the curing is terminated when the internal stress change rate of the concrete is less than 0.01 MPa / d for three consecutive days; the above internal stress change rate of the concrete is determined by the stress data.

[0030] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0031] The water retention film formed in the initial setting stage can seal the fine pores on the concrete surface, reduce the water evaporation amount, effectively inhibit plastic shrinkage cracks, and solve the early cracking caused by rapid water evaporation; compared with simple water spraying curing, the film-forming agent can avoid the adverse effects of surface water saturation on the hydration reaction; the water is evenly distributed through the composite curing layer, eliminating local dry-wet differences, reflecting solar radiation, reducing the surface temperature, and reducing temperature stress cracks. The humidity of the concrete is monitored through a humidity sensor, and water is replenished as needed, reducing the water resource consumption compared with timed spraying, achieving a water-saving effect; it also solves the contradiction of "strength reduction caused by excessive water replenishment" or "shrinkage caused by insufficient water replenishment" in traditional curing. Through the environmental temperature, atomizing spraying during high-temperature periods reduces the concrete surface temperature and controls the temperature difference between the inside and outside of the concrete. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the following will briefly introduce the drawings required in the embodiments. It should be understood that the following drawings only show some embodiments of the present invention, and therefore should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can also be obtained based on these drawings without creative efforts. In the drawings:

[0033] Figure 1 is the main flow chart. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0034] To make the purpose, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below in combination with the embodiments and the drawings. The illustrative embodiments and descriptions thereof of the present invention are only used to explain the present invention and are not used to limit the present invention.

[0035] Example:

[0036] Combined with Figure 1 , in the initial setting stage of concrete (2 - 4 hours after pouring), an acrylic-based film-forming agent (preferably adding 1% - 3% nano-silica) is used for surface spraying to form a water-retaining film layer with a thickness of 0.05 - 0.1 mm, effectively sealing the fine pores on the concrete surface and reducing water evaporation; a composite curing layer is covered on the concrete after the water-retaining film layer is formed. The composite curing layer includes a water-absorbent non-woven fabric and a reflective aluminum foil film. The water-absorbent non-woven fabric (gram weight ≥ 200 g / m²) is directly attached to the upper surface of the water-retaining film layer, evenly absorbing and slowly releasing water; the reflective aluminum foil film (reflectivity ≥ 85%) has its edges fixed by magnetic strips, and has functions of heat insulation, water retention and wind prevention.

[0037] Humidity sensors are arranged in a grid pattern (spacing ≤ 2m × 2m, burial depth 10 - 15 mm) to monitor the humidity of concrete in real time; microporous water pipes (pore diameter 0.1 - 0.3 mm) supply water at fixed points according to the data of humidity sensors, and automatically start watering when the humidity < 90%.

[0038] Phase change material capsules (paraffin type, phase change temperature 28 - 32 °C) are embedded in the composite curing layer to buffer temperature fluctuations; the atomizing spray system starts intermittently during high-temperature periods (10:00 - 16:00 when > 30 °C) to reduce the surface temperature of concrete; dynamic temperature control is achieved through phase change material capsules and the atomizing spray system.

[0039] The internal stress change of concrete is monitored by a fiber optic sensor. When the stress change rate is continuously < 0.01 MPa / d for 3 days, it is determined that the curing is qualified. Among them, the above-mentioned internal stress change rate of concrete is the ratio of adjacent stress data.

[0040] A reference usage scenario is for curing the concrete of the foundation slab of a high-rise building. Concrete grade: C40P8, pouring volume: 1200 m³, environmental conditions: maximum daytime temperature 35 °C, relative humidity 40%, wind speed 3 m / s; the specific implementation steps are as follows:

[0041] Three hours after concrete pouring, an electric sprayer was used to evenly spray an acrylic-nano silica composite film-forming agent (with a nano-SiO₂ content of 2%) at a dosage of 0.15 kg / m² to form a continuous water-retaining film layer with a thickness of approximately 0.08 mm. A polyester fiber non-woven fabric with a weight of 250 g / m² was selected. During laying, it was ensured that it was completely adhered to the concrete surface, and the overlapping width at the joints was ≥100 mm. An aluminum foil composite reflective film was laid, and the edges were fixed with magnetic rubber strips (at an interval of 500 mm), and the corners were strengthened for fixation. A humidity sensor of model SHT35 was selected and embedded in the concrete according to a 1.5 m × 1.5 m grid, with a burial depth of 12 mm. A temperature measurement optical cable was arranged along the steel mesh to monitor the ambient temperature. The humidity threshold was set at 90%. When the humidity at the monitoring point was <90%, the microporous water seepage pipe in the corresponding area was started, and the water replenishment time was 3 - 5 minutes per time. Paraffin / graphene composite phase change capsules (with a phase change temperature of 30°C) were used, and the arrangement density was 6 per m². When the surface temperature >32°C, the atomizing spray was turned on (lasting for 2 minutes each time, with an interval of 15 minutes). The inspection of the curing effect showed that the highest temperature inside the concrete was 56°C (compared with 62°C in the traditional curing control group), the surface humidity was maintained at 92 - 95%RH, and the maximum temperature difference between the inside and outside was 23°C (meeting the specification requirements). The quality inspection results were as follows: the compliance rate of the 28-day compressive strength was 100%, the surface cracks were 0.05 pieces / m² (compared with 0.4 pieces / m² in the control group), and the chloride ion penetration coefficient was <1000C.

[0042] A reference usage scenario for curing concrete pavement in high-temperature and arid areas. The concrete grade is C30, the construction area is 5000 m², and the environmental conditions are: the highest daytime temperature is 42°C, and the relative humidity is 25%. The specific implementation steps are as follows:

[0043] 3% nano-SiO₂ was added to the film-forming agent, the spraying amount was increased to 0.18 kg / m², the gram weight of the non-woven fabric was increased to 300 g / m², and an anti-ultraviolet coating was applied to the surface of the aluminum foil film. The phase change material capsules were increased to 8 per m², and the atomizing spray frequency was increased to once per hour to achieve temperature control optimization. After testing, the water evaporation amount was reduced by 65% (compared with traditional curing), no temperature cracks were found on the surface, and the curing period was shortened to 18 days (traditionally 25 days).

[0044] A reference usage scenario for curing concrete during winter construction. The concrete grade is C50, and the environmental conditions are: the average daily temperature is -5°C, and the lowest is -12°C. The specific implementation steps are as follows:

[0045] Adopt a low-temperature acrylate film-forming agent (cold-resistant to -20°C). For the lower layer of the composite curing layer, use 400 g / m² thickened non-woven fabric, for the middle layer, use aerogel thermal insulation felt, and for the upper layer, use aluminum foil reflective film; change the phase change material to octadecane (phase change temperature 28°C), and add an electric tracing heating system to assist in heat preservation; after testing, the internal temperature of the concrete is maintained above 15°C, the 28-day strength reaches 105% of the design value, and there are no frostbite marks on the surface.

[0046] The specific implementation manners described above further elaborate on the purpose, technical solutions, and beneficial effects of the present invention. It should be understood that the above are only the specific implementation manners of the present invention and are not used to limit the protection scope of the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the protection scope of the present invention.

Claims

1. A construction concrete curing process, characterized in that, It includes the following steps: Conduct surface film-forming treatment in the initial setting stage of concrete; Lay a composite curing layer with water retention and reflection functions; Monitor the humidity of concrete through buried humidity sensors to obtain humidity data; Control the operation of the local water replenishment system according to the humidity data; Implement dynamic temperature regulation in combination with the ambient temperature.

2. The construction concrete curing process according to claim 1, wherein: The surface film-forming treatment uses an acrylic-based film-forming agent, and the spraying amount is 0.1 - 0.2 kg / m², forming a water retention film layer with a thickness of 0.05 - 0.1 mm.

3. The construction concrete curing process according to claim 2, wherein: Add 1 - 3 wt% of nano-silica particles with a particle size of 20 - 50 nm to the acrylic-based film-forming agent.

4. The construction concrete curing process according to claim 1, characterized in that: The composite curing layer includes a water-absorbing non-woven fabric layer and a reflective aluminum foil film layer. The water-absorbing non-woven fabric layer directly contacts the concrete surface, and the weight of the water-absorbing non-woven fabric layer per square meter is greater than or equal to 200 g; The reflective aluminum foil film layer covers the upper surface of the water-absorbing non-woven fabric layer, and the reflectivity of the reflective aluminum foil film layer is greater than or equal to 85%.

5. The construction concrete curing process according to claim 4, characterized in that: A magnetic fixing strip is arranged at the edge of the reflective aluminum foil film, and the reflective aluminum foil film is connected to the embedded parts buried in the concrete through the magnetic fixing strip.

6. The construction concrete curing process according to claim 1, characterized in that: The humidity sensors are arranged in a matrix, and the distance between adjacent humidity sensors is less than 2 m; the monitoring depth of the humidity sensors is 10 - 15 mm.

7. The construction concrete curing process according to claim 1, characterized in that: The local water replenishment system includes: A microporous water permeable pipe arranged in the composite curing layer, and the aperture of the microporous water permeable pipe is 0.1 - 0.3 mm; When any one of the humidity sensors detects that the humidity is lower than 90%, start the water replenishment of the microporous water permeable pipe in the corresponding area of the humidity sensor.

8. The construction concrete curing process according to claim 1, characterized in that: The dynamic temperature regulation includes: When the ambient temperature is greater than 30°C, start the atomizing spraying system at a preset time period every day; Phase change material capsules are arranged in the composite curing layer, and phase change materials are loaded in the phase change material capsules; The phase change temperature of the phase change material capsules is 28 - 32°C.

9. The construction concrete curing process according to any one of claims 1 to 8, characterized in that: It also includes a curing quality monitoring step, monitor the internal stress data of the concrete through buried optical fiber sensors, and dynamically adjust the curing period according to the stress data.

10. The construction concrete curing process according to claim 9, wherein: The curing period is 14 - 28 days, and the curing is terminated when the internal stress change rate of the concrete is less than 0.01 MPa / d for 3 consecutive days; the internal stress change rate of the concrete is determined by the stress data.

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