阅读说明：本技术 大体积混凝土基础冬季施工减少内外温差的方法 (Method for reducing internal and external temperature difference during winter construction of mass concrete foundation ) 是由 彭磊加 杨景浩 李义贤 徐秀丽 刘涛 何静 于 2019-09-16 设计创作，主要内容包括：本发明公开了一种大体积混凝土基础冬季施工减少内外温差的方法,其包括以下步骤：步骤S1、铺设垫层；步骤S2、搭设模板框架；步骤S3、浇筑混凝土；步骤S4、混凝土的养护；步骤S5、拆除模板。本发明通过将大体积混凝土内部的热量传递至外部,进而实现无需设置额外的冷源或热源,即可达到降低大体积混凝土的内外温差的施工效果,保证施工质量,提高施工工效,降低施工成本。(The invention discloses a method for reducing internal and external temperature difference of mass concrete foundation in winter construction, which comprises the following steps: step S1, paving a cushion layer; step S2, setting up a template frame; step S3, pouring concrete; step S4, curing the concrete; and step S5, removing the template. According to the invention, the heat inside the mass concrete is transferred to the outside, so that the construction effect of reducing the temperature difference between the inside and the outside of the mass concrete can be achieved without arranging an additional cold source or a heat source, the construction quality is ensured, the construction efficiency is improved, and the construction cost is reduced.)

1. The method for reducing the internal and external temperature difference in the winter construction of the large-volume concrete foundation is characterized by comprising the following steps of:

step S1, paving a cushion layer: cleaning a foundation bearing platform, spreading a concrete cushion layer on the surface of the foundation bearing platform, doping an antifreezing agent into the concrete cushion layer, wherein the addition amount of the antifreezing agent is 1% of the total mass of the concrete cushion layer, and covering the surface of the concrete cushion layer with a flame-retardant heat-preservation quilt after the concrete cushion layer is vibrated and leveled;

step S2, setting up a template frame: after the concrete cushion is solidified and reaches the frost resistance strength, removing the heat preservation quilt, arranging a waterproof layer on the upper surface of the concrete cushion, binding a reinforcement cage on the upper surface of the waterproof layer, laying a plurality of radiating pipes in the reinforcement cage, correspondingly arranging a layer of radiating pipe on each layer of steel bar in the vertical direction, arranging a plurality of radiating pipes at intervals along the length direction of the reinforcement cage on any layer of steel bar, along the width direction of the reinforcement cage, wherein any two radiating pipes are not interfered with each other, and arranging a pre-embedded temperature measuring part on any radiating pipe to set a temperature measuring point; then, respectively coating templates on the periphery of the outer surface of the reinforcement cage;

wherein, any template comprises a template body, a heat-insulating layer and a buffer layer which are fixedly connected in sequence from the outside to the inside of the reinforcement cage; the heat preservation layer comprises a first shell and a second shell which are sleeved inside and outside, the first shell and the second shell are both of hollow three-dimensional structures, a hollow annular space is formed between the first shell and the second shell, one side of the annular space is provided with an air inlet which is communicated with an air outlet of an external air pump air compressor, and the other side of the annular space is provided with an air outlet which is communicated with an air inlet of the external air pump air compressor; white sand is filled in the first shell, and one side surface of the second shell, which is close to the template body, is fixedly connected with the side surface of the template body in a sealing manner; the buffer layer comprises an inner inflatable rubber layer and a steel plate body, two side surfaces of the rubber layer are respectively fixedly connected with the other side surface of the second shell in a sealing way, and one side surface of the steel plate body close to the template body is fixedly connected in a sealing way; the air charging hole of the rubber layer can be communicated with an air outlet of an external blower;

any radiating pipe is of a serpentine structure made of aluminum alloy and is of a double-layer structure with a hollow interlayer, a plurality of guide pipes are arranged on the pipe wall of the radiating pipe at intervals, one end of any guide pipe extends into the radiating pipe, and the other end of any guide pipe extends to the outside of the radiating pipe along the radial direction of the radiating pipe; the inner tubes of the radiating tubes penetrate through the two ends of the outer tube opposite to the inner tubes respectively and continue to extend into the adjacent first shell, the two ends of the inner tubes of the radiating tubes are sealed, and the two ends of the interlayers of the radiating tubes are communicated with the adjacent annular space respectively;

step S3, pouring concrete: the method comprises the following steps of adopting integral layered continuous casting, wherein the casting thickness of each layer of concrete is 500-800 mm, and vibrating after the casting of each layer of concrete is finished; within 3-4 h after the large-volume concrete is poured, the upper surface of the concrete is scraped by a horizontal scraping ruler, then the upper surface of the concrete is rolled for 2 times by an iron roller, then the upper surface of the concrete is rubbed and compacted by a trowel, and finally a sealing layer is coated on the upper surface of the concrete;

step S4, curing of concrete: after concrete pouring is finished, a horizontal scraper is used for scraping the upper surface of the concrete, an air blower is started to fill air into the rubber layer, an air pump air compressor is started to introduce circulating air into the annular space, and the temperature of the air introduced by the air pump air compressor is controlled according to the difference value between the temperature inside the concrete and the temperature of the upper surface of the concrete monitored in real time; covering a plurality of layers of geotextiles, a plurality of layers of plastic films and a plurality of layers of straw bags on the upper surface of the sealing layer in the step S3 to form an insulating layer; wherein, the geotextile is wetted by water before being laid;

step S5, removing the template: when the temperature difference between the surface temperature of the concrete and the lowest outdoor temperature is less than 20 ℃ and the temperature difference between the upper surface of the concrete and the center temperature of the concrete is less than 20 ℃, closing an air pump air compressor, stopping ventilation, and then removing the straw bags, the plastic films and the geotextiles layer by layer from top to bottom; and after the concrete is completely solidified and the strength meets the requirement, closing the air blower and removing the template.

2. The method for reducing the difference between the internal temperature and the external temperature during the winter construction of the mass concrete foundation as claimed in claim 1, wherein in step S2, two layers of scaffolds are erected outside the formwork from the inside to the outside, the horizontal distance between the inner scaffold and the formwork body is 300mm, the horizontal distance between the inner scaffold and the outer scaffold is 1050mm, and the peripheral outer surfaces of the outer scaffold are sealed by three-proofing cloth; in step S4, when the difference between the temperature inside the concrete and the temperature of the upper surface of the concrete exceeds 20 ℃, a fire is set between two layers of scaffolding and the fire is ignited.

3. The method of claim 2, wherein the reinforcement of the reinforcement cage is mechanically sleeved together.

4. The method for reducing the difference between the internal temperature and the external temperature during the winter construction of the mass concrete foundation as claimed in claim 3, wherein the concrete slurry used for pouring is Portland slag cement with low hydration heat.

5. The method for reducing the difference between the inside temperature and the outside temperature in winter construction of mass concrete foundation as claimed in claim 4, wherein the anti-freezing agent in step S1 is YNF-9B polycarboxylic acid anti-freezing agent.

6. The method for reducing the internal and external temperature difference during the winter construction of the mass concrete foundation as claimed in claim 5, wherein in the step S3, the vibrating after the concrete pouring of each layer is specifically as follows: the vibrating time is 15-20 s, the vibrating rod is inserted into the lower concrete part of the concrete, and the insertion depth is 50-100 mm.

Technical Field

The invention relates to the technical field of buildings. More particularly, the present invention relates to a method for reducing internal and external temperature differences in the winter construction of mass concrete foundations.

Background

The winter construction technology for mass concrete is to ensure the construction of mass concrete in cold winter, represents very important value for complex construction procedures and strict quality requirements and under the condition of ensuring safe construction, and increases value for project value by ensuring that the project schedule can reach production as soon as possible for subsequent equipment and process pipeline installation of the project.

With the continuous development of economy, the demand of coal chemical enterprises in China is increased year by year. In coal chemical engineering, large-volume commercial concrete occupies a large part, the construction period is short, the process is complex, winter construction cannot be avoided, construction sites are cold in winter, tests are brought to the construction of the large-volume commercial concrete, more scientific winter construction measures need to be taken, the construction process is reasonably arranged, advanced construction technology and construction technology are adopted, multiple measures are taken, the winter construction quality of the large-volume commercial concrete is ensured only by taking the measures, and the development of the large-volume concrete winter construction optimization technology is necessarily developed towards scale, standardization and internationalization.

Disclosure of Invention

An object of the present invention is to solve at least the above problems and to provide at least the advantages described later.

The invention also aims to provide a method for reducing the internal and external temperature difference of the mass concrete foundation in winter construction, which can achieve the construction effect of reducing the internal and external temperature difference of the mass concrete without arranging an additional cold source or heat source by transferring the heat inside the mass concrete to the outside, thereby ensuring the construction quality, improving the construction efficiency and reducing the construction cost.

To achieve these objects and other advantages in accordance with the purpose of the invention, there is provided a method for reducing internal and external temperature differences in winter construction of a mass concrete foundation, comprising the steps of:

step S1, paving a cushion layer: cleaning a foundation bearing platform, spreading a concrete cushion layer on the surface of the foundation bearing platform, doping an antifreezing agent into the concrete cushion layer, wherein the addition amount of the antifreezing agent is 1% of the total mass of the concrete cushion layer, and covering the surface of the concrete cushion layer with a flame-retardant heat-preservation quilt after the concrete cushion layer is vibrated and leveled;

step S2, setting up a template frame: after the concrete cushion is solidified and reaches the frost resistance strength, removing the heat preservation quilt, arranging a waterproof layer on the upper surface of the concrete cushion, binding a reinforcement cage on the upper surface of the waterproof layer, laying a plurality of radiating pipes in the reinforcement cage, correspondingly arranging a layer of radiating pipe on each layer of steel bar in the vertical direction, arranging a plurality of radiating pipes at intervals along the length direction of the reinforcement cage on any layer of steel bar, along the width direction of the reinforcement cage, wherein any two radiating pipes are not interfered with each other, and arranging a pre-embedded temperature measuring part on any radiating pipe to set a temperature measuring point; then, respectively coating templates on the periphery of the outer surface of the reinforcement cage;

wherein, any template comprises a template body, a heat preservation layer and a buffer layer which are sequentially overlapped from the outside to the inside of the reinforcement cage; the heat preservation layer comprises a first shell and a second shell which are sleeved inside and outside, the first shell and the second shell are both of hollow three-dimensional structures, a hollow annular space is formed between the first shell and the second shell, one side of the annular space is provided with an air inlet which is communicated with an air outlet of an external air pump air compressor, and the other side of the annular space is provided with an air outlet which is communicated with an air inlet of the external air pump air compressor; white sand is filled in the first shell, and one side surface of the second shell, which is close to the template body, is fixedly connected with the side surface of the template body in a sealing manner; the buffer layer comprises an inner inflatable rubber layer and a steel plate body, two side surfaces of the rubber layer are respectively fixedly connected with the other side surface of the second shell in a sealing way, and one side surface of the steel plate body close to the template body is fixedly connected in a sealing way; the air charging hole of the rubber layer can be communicated with an air outlet of an external blower;

any radiating pipe is of a serpentine structure made of aluminum alloy and is of a double-layer structure with a hollow interlayer, a plurality of guide pipes are arranged on the pipe wall of the radiating pipe at intervals, one end of any guide pipe extends into the radiating pipe, and the other end of any guide pipe extends to the outside of the radiating pipe along the radial direction of the radiating pipe; the inner tubes of the radiating tubes penetrate through the two ends of the outer tube opposite to the inner tubes respectively and continue to extend into the adjacent first shell, the two ends of the inner tubes of the radiating tubes are sealed, and the two ends of the interlayers of the radiating tubes are communicated with the adjacent annular space respectively;

step S3, pouring concrete: the method comprises the following steps of adopting integral layered continuous casting, wherein the casting thickness of each layer of concrete is 500-800 mm, and vibrating after the casting of each layer of concrete is finished; within 3-4 h after the large-volume concrete is poured, the upper surface of the concrete is scraped by a horizontal scraping ruler, then the upper surface of the concrete is rolled for 2 times by an iron roller, then the upper surface of the concrete is rubbed and compacted by a trowel, and finally a sealing layer is coated on the upper surface of the concrete;

step S4, curing of concrete: after concrete pouring is finished, a horizontal scraper is used for scraping the upper surface of the concrete, an air blower is started to fill air into the rubber layer, an air pump air compressor is started to introduce circulating air into the annular space, and the temperature of the air introduced by the air pump air compressor is controlled according to the difference value between the temperature inside the concrete and the temperature of the upper surface of the concrete monitored in real time; covering a plurality of layers of geotextiles, a plurality of layers of plastic films and a plurality of layers of straw bags on the upper surface of the sealing layer in the step S3 to form an insulating layer; wherein, the geotextile is wetted by water before being laid;

step S5, removing the template: when the temperature difference between the surface temperature of the concrete and the lowest outdoor temperature is less than 20 ℃ and the temperature difference between the upper surface of the concrete and the center temperature of the concrete is less than 20 ℃, closing an air pump air compressor, stopping ventilation, and then removing the straw bags, the plastic films and the geotextiles layer by layer from top to bottom; and after the concrete is completely solidified and the strength meets the requirement, closing the air blower and removing the template.

Preferably, in the method for reducing the internal and external temperature difference in the large-volume concrete foundation in winter construction, in step S2, two layers of scaffolds are erected outside the formwork from inside to outside, the horizontal distance between the inner-layer scaffold and the formwork body is 300mm, the horizontal distance between the inner-layer scaffold and the outer-layer scaffold is 1050mm, and the peripheral outer surfaces of the outer-layer scaffold are sealed by three-proofing cloth; in step S4, when the difference between the temperature inside the concrete and the temperature of the upper surface of the concrete exceeds 20 ℃, a fire is set between two layers of scaffolding and the fire is ignited.

Preferably, the method for reducing the internal and external temperature difference in the large-volume concrete foundation in winter construction is characterized in that the steel bars of the steel reinforcement cage are connected by a mechanical sleeve.

Preferably, the method for reducing the internal and external temperature difference in the construction of the mass concrete foundation in winter adopts slag portland cement with low hydration heat as concrete slurry for pouring.

Preferably, in the method for reducing the internal and external temperature difference in the large-volume concrete foundation in winter construction, the antifreezing agent in the step S1 is YNF-9B polycarboxylic acid antifreezing agent.

Preferably, in the method for reducing the internal and external temperature difference in the large-volume concrete foundation in winter construction, in step S3, the vibrating operation after the pouring of each concrete layer is specifically: the vibrating time is 15-20 s, the vibrating rod is inserted into the lower concrete part of the concrete, and the insertion depth is 50-100 mm.

The invention at least comprises the following beneficial effects:

1. according to the invention, the heat inside the mass concrete is transferred to the outside, so that the construction effect of reducing the temperature difference between the inside and the outside of the mass concrete can be achieved without arranging an additional cold source or a heat source, the construction quality is ensured, the construction efficiency is improved, and the construction cost is reduced;

2. according to the invention, the heat-insulating layer and the buffer layer are arranged on the inner side of the template, sand with good heat conduction and heat storage performance is filled in the first shell of the heat-insulating layer, the interior of concrete is communicated with the sand layer through the radiating pipe to form a heat transfer channel, heat generated in the concrete is conducted to the sand through the radiating pipe made of an aluminum alloy material, the internal heat is directly supplied to the peripheral outer surface of the concrete, the internal and external temperature difference is reduced, meanwhile, air can be introduced into the annular space through the air pump air compressor, the air can be air in a real-time environment, a refrigerating device can also be connected onto the air pump air compressor to cool the air introduced into the annular space, the air in the annular space is introduced into the interlayer of the radiating pipe, the heat in the concrete is further conducted to the outer surface of the concrete, and the purpose of further;

the air blower can be used for filling air into the rubber layer of the buffer layer, the concrete can shrink in the solidification process, the elastic rubber layer can generate an acting force for extruding the concrete into the reinforcement cage, and therefore the concrete is prevented from shrinking all around in the solidification process, cracks are generated in the concrete, and the construction quality is guaranteed;

3. according to the invention, the radiating pipe is of a double-layer structure, the side wall of the radiating pipe is provided with the plurality of guide pipes, concrete poured into the steel reinforcement cage can enter the radiating pipe through the plurality of guide pipes, and the radiating pipe is ensured not to influence the strength of the poured concrete in the steel reinforcement cage; compared with a cooling pipe which is filled with cold water in the prior art, the radiating pipe has higher strength, can be better fused with concrete slurry, can achieve the effects of cooling and heat conduction, and cannot influence the strength in the concrete.

Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention.

Drawings

Fig. 1 is a schematic view of the structure of the heat pipe and the mold plate of the present invention.

Detailed Description

The present invention is further described in detail below with reference to the drawings and examples so that those skilled in the art can practice the invention with reference to the description.

It will be understood that terms such as "having," "including," and "comprising," as used herein, do not preclude the presence or addition of one or more other elements or groups thereof.

In the description of the present invention, the terms "lateral", "longitudinal", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, are only for convenience in describing the present invention and simplifying the description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention.

The invention provides a method for reducing internal and external temperature difference of mass concrete foundation in winter construction, which comprises the following steps:

step S1, paving a cushion layer: cleaning a foundation bearing platform, paving a concrete cushion layer 1 on the surface of the foundation bearing platform, doping YNF-9B polycarboxylic acid antifreezing agent into the concrete cushion layer 1, wherein the addition amount of the polycarboxylic acid antifreezing agent is 1% of the total mass of the concrete cushion layer 1, and covering the surface of the concrete cushion layer 1 with flame retardant and heat preservation after the concrete cushion layer 1 is vibrated and leveled to be maintained;

step S2, setting up a template frame: after the concrete cushion layer 1 is solidified and reaches the frost resistance strength, removing the heat preservation quilt, arranging a waterproof layer on the upper surface of the concrete cushion layer 1, binding a reinforcement cage on the upper surface of the waterproof layer, and connecting the reinforcement of the reinforcement cage by adopting a mechanical sleeve; a plurality of radiating pipes are laid in the reinforcement cage, a layer of radiating pipe is correspondingly arranged on each layer of reinforcement along the vertical direction, a plurality of radiating pipes are arranged at intervals on any layer of reinforcement along the width direction of the reinforcement cage along the length direction of the reinforcement cage, any two radiating pipes are not interfered with each other, a pre-buried temperature measuring part is arranged on any radiating pipe, and a temperature measuring point is arranged; then, respectively coating templates on the periphery of the outer surface of the reinforcement cage; two layers of scaffolds are also erected outside the template from the inside to the outside, the horizontal distance between the inner layer scaffold and the template body 21 is 300mm, the horizontal distance between the inner layer scaffold and the outer layer scaffold is 1050mm, and the peripheral outer surface of the outer layer scaffold is sealed by three-proofing cloth; the scaffold is a floor scaffold, and a fastener type steel pipe scaffold with the specification of phi 48 multiplied by 3.0mm is selected;

as shown in fig. 1, each formwork comprises a formwork body 21, an insulating layer and a buffer layer which are sequentially stacked from the outside to the inside of the reinforcement cage; the heat-insulating layer comprises a first shell 23 and a second shell 22 which are sleeved inside and outside, the first shell 23 and the second shell 22 are both of hollow three-dimensional structures, a hollow annular space 24 is formed between the first shell 23 and the second shell 22, one side of the annular space 24 is provided with an air inlet which is communicated with an air outlet of an external air pump air compressor, and the other side of the annular space 24 is provided with an air outlet which is communicated with the air inlet of the external air pump air compressor; white sand is filled in the first shell 23, and one side surface of the second shell 22 close to the template body 21 is fixedly connected with the side surface of the template body 21 in a sealing manner; the buffer layer comprises an inner inflatable rubber layer and a steel plate body, two side surfaces of the rubber layer are respectively fixedly connected with the other side surface of the second shell 22 in a sealing way, and one side surface of the steel plate body close to the template body 21 is fixedly connected in a sealing way; the air charging hole of the rubber layer can be communicated with an air outlet of an external blower;

any radiating pipe is of a serpentine structure made of aluminum alloy and is of a double-layer structure with a hollow interlayer 33, a plurality of guide pipes 34 are arranged on the pipe wall of the radiating pipe at intervals, one end of any guide pipe 34 extends into the radiating pipe, and the other end of the guide pipe extends to the outside of the radiating pipe along the radial direction of the radiating pipe; the inner pipe 31 of the radiating pipe penetrates out of the two ends of the outer pipe 32 opposite to the inner pipe and continues to extend to the adjacent inner part of the first shell 23, the two ends of the inner pipe 31 of the radiating pipe are sealed, and the two ends of the interlayer 33 of the radiating pipe are respectively communicated with the adjacent inner part of the annular space 24;

step S3, pouring concrete: slag portland cement with low hydration heat is selected as concrete slurry for pouring; the method adopts integral layered continuous pouring, the pouring thickness of each layer of concrete is 500-800 mm, and the concrete is vibrated after the pouring of each layer of concrete is finished, and the method specifically comprises the following steps: the vibrating time is 15-20 s, the vibrating rod is inserted into the lower concrete of the concrete, the insertion depth is 50-100 mm, and cracks between two adjacent layers of concrete are eliminated; within 3-4 h after the large-volume concrete is poured, the upper surface of the concrete is scraped by a horizontal scraping ruler, then the upper surface of the concrete is rolled for 2 times by an iron roller, then the upper surface of the concrete is rubbed and compacted by a trowel, and finally a sealing layer is coated on the upper surface of the concrete;

step S4, curing of concrete: after concrete pouring is finished, a horizontal scraper is used for scraping the upper surface of the concrete, an air blower is started to fill air into the rubber layer, an air pump air compressor is started to introduce circulating air into the annular space 24, the temperature of the air introduced by the air pump air compressor is controlled according to the difference value between the temperature inside the concrete and the temperature of the upper surface of the concrete monitored in real time, and when the difference value between the temperature inside the concrete and the temperature of the upper surface of the concrete exceeds 20 ℃, a condensing device is arranged on the air pump air compressor to properly cool the air introduced into the annular space 24; covering a plurality of layers of geotextiles, a plurality of layers of plastic films and a plurality of layers of straw bags on the upper surface of the sealing layer in the step S3 to form an insulating layer; wherein, the geotextile is wetted by water before being laid; when the difference between the internal temperature of the concrete and the temperature of the upper surface of the concrete exceeds 20 ℃, arranging a furnace between the two layers of scaffolds, and igniting the furnace;

step S5, removing the template: when the temperature difference between the surface temperature of the concrete and the lowest outdoor temperature is less than 20 ℃ and the temperature difference between the upper surface of the concrete and the center temperature of the concrete is less than 20 ℃, closing an air pump air compressor, stopping ventilation, and then removing the straw bags, the plastic films and the geotextiles layer by layer from top to bottom; and after the concrete is completely solidified and the strength meets the requirement, closing the air blower, removing the template, preferably removing the template in the daytime, closing the air blower, discharging the gas in the rubber layer, removing the connecting piece between the template and the reinforcement cage, removing the template, and finally cutting off the part of the radiating pipe protruding out of the outer surface of the concrete.

The number of apparatuses and the scale of the process described herein are intended to simplify the description of the present invention. Applications, modifications and variations of the present invention will be apparent to those skilled in the art.

While embodiments of the invention have been described above, it is not limited to the applications set forth in the description and the embodiments, which are fully applicable in various fields of endeavor to which the invention pertains, and further modifications may readily be made by those skilled in the art, it being understood that the invention is not limited to the details shown and described herein without departing from the general concept defined by the appended claims and their equivalents.