Subway viaduct construction heating formwork concrete curing system and curing method

Abstract

The invention discloses a subway viaduct construction heating formwork concrete curing system and curing method, and belongs to the technical field of concrete curing systems. Comprising a pouring formwork, a heating module, a heat insulation module, a temperature transmitter and a temperature control box, and formwork back ribs are fixed to the back face of the pouring formwork at intervals; the heating module comprises electric heating wires, the electric heating wires are pasted and fixed to the back face of the pouring formwork and arranged in gaps between back ribs of the formwork, and the wiring distance of the electric heating wires on the pouring formwork is 300 mm; the heat insulation and preservation module comprises an aluminum foil heat reflection film, and the aluminum foil heat reflection film is pasted in a gap between the formwork back ribs and wraps the back face of the electric heating wire. Heat preservation cotton is pressed on one surface, far away from the electric heating wire, of the aluminum foil heat reflection film; according to the heating formwork concrete curing system and method for subway viaduct construction, heat preservation sealing treatment can be conducted on concrete in the pouring formwork, and concrete sealing curing is achieved.

Description

Technical Field

[0001] The invention specifically relates to a heating formwork concrete curing system and a curing method for subway viaduct construction, and belongs to the technical field of concrete curing systems. Background Art

[0002] Concrete itself has various requirements for the environment, such as the requirements for ambient temperature and temperature difference for concrete hardening. Only when these requirements are met can cement exert its due performance characteristics. It is basically difficult to change the properties of cement in our on-site construction to adapt it to various external conditions. Therefore, it is necessary to provide an environment suitable for concrete hardening to exert the best effect of cement. In the existing technology, for winter concrete pouring construction, the current measures of concrete surface insulation and external environmental heating are basically adopted, such as greenhouse steam, greenhouse furnaces, etc. There are many problems in the implementation of these practices, such as poor construction effect, high energy consumption, uneven temperature control, and failure to control the construction. The temperature of the working part cannot be accurately adjusted, especially the artificial intelligence adjustment cannot be performed, the construction process consumes a lot of manual labor, and the construction safety is poor; the existing concrete curing device, such as Chinese patent publication number: CN117780132A, discloses a concrete heating and curing device, which includes multiple heating templates, multiple fixed templates and multiple groups of temperature measuring devices. During the actual curing process, the concrete heating and curing device can monitor the temperature of the concrete in real time, so that the concrete is always at a more suitable curing temperature, which is conducive to ensuring the curing quality of the concrete; when the structure cannot achieve closed insulation treatment of the concrete, the curing energy consumption is still relatively serious. Summary of the invention

[0003] In order to solve the above problems, the present invention proposes a subway viaduct construction heated formwork concrete curing system and curing method, which can perform insulation and sealing treatment on the concrete in the casting formwork to achieve closed curing of the concrete.

[0004] A subway viaduct construction heating formwork concrete curing system, comprising: A casting template, wherein template back ribs are fixed at intervals on the back of the casting template; A heating module, wherein the heating module comprises an electric heating wire, and the electric heating wire is adhered and fixed to the casting template between the back ribs of the template, and the wiring spacing of the electric heating wire on the casting template is 300 mm; A heat insulation module, the heat insulation module comprises an aluminum foil heat reflective film, the aluminum foil heat reflective film is pasted between the back ribs of the template and covers the electric heating wire, the aluminum foil heat reflective film is pressed with heat insulation cotton on the side facing outward, the heat insulation cotton is pressed with a pressing plate on the side facing outward, and the pressing plate is fixed to the inner surface of the back ribs of the template; A temperature transmitter, wherein the temperature transmitter is installed on the back of the casting formwork, the surface of the concrete or inside the concrete; The temperature control box, the temperature transmitter is connected to the temperature control box; the electric heating wire is connected to the temperature control box through a safety protector.

[0005] The heating formwork concrete curing system for subway viaduct construction of the present invention can perform insulation and sealing treatment on the poured concrete, and perform electric heating and intelligent temperature control between the heat insulation module and the concrete; during the concrete construction process, the concrete surface is sealed on the basis of the current construction process, and the concrete sealed inside is temperature controlled and insulated, so that the concrete can be hardened in the state of being isolated from the external environment during construction; information is collected by temperature transmitters arranged on the back of the pouring formwork, the concrete surface and the inside of the concrete, and the information is sent to the temperature control box, which controls the electric heating wire through a set program to obtain the concrete construction status and intelligent information control in real time.

[0006] Furthermore, the system installation process is as follows: clean the back of the casting formwork, remove oil stains and adhered concrete; then, stick the electric heating wire and the temperature transmitter in the gap between the back ribs of the casting formwork, and stick the cut aluminum foil heat reflective film on the casting formwork behind the electric heating wire according to the spacing of the back ribs of the formwork, so that the electric heating wire is between the casting formwork and the aluminum foil heat reflective film; according to the spacing size of the back ribs of the formwork, install the appropriately cut insulation cotton in the gap between the back ribs of the formwork, press the back of the insulation cotton with a pressing plate, and fix the pressing plate firmly; finally, connect the electric heating wire and the temperature transmitter to the temperature control box.

[0007] After the concrete is poured and the surface is covered, connect the power supply of the temperature control box to perform intelligent temperature control. When the temperature is low, in order to prevent freezing damage during the concrete pouring process, the formwork can be preheated for a period of time in advance. Before the device works, focus on checking whether the line is damaged, whether there are any leakage parts, whether the intelligent temperature control switch is intact, whether the leakage protection device is qualified, and whether the insulation of the line joints meets the requirements. Check whether there is any damage to the electric heating wire during the construction process, especially the burning of the heating wire by electric welding during construction, which causes the heating wire to stick to the formwork and cause leakage. The fault must be eliminated, and a power-on test must be done before each use.

[0008] Furthermore, the temperature transmitter is also bonded to the front side of the casting template to complete the concrete surface temperature monitoring, and after the concrete is poured, the temperature transmitter is embedded in the concrete to complete the concrete internal temperature monitoring.

[0009] Furthermore, a plurality of screw holes are provided on the casting template, and hollow bolts are screwed into the screw holes; a collection line passes through the hollow bolt and epoxy resin is poured therein, and the collection line is connected to a temperature transmitter fixed on a steel cage of the concrete; the internal temperature of the concrete can be monitored by the temperature transmitter; after the casting is completed, the collection line can be directly cut off.

[0010] Furthermore, the electric heating wire is composed of an electric heating wire and an electromagnetic induction coil; the electromagnetic induction coil is connected to an alternating current of appropriate size and frequency, which will generate an eddy current electromagnetic field in the casting formwork and the concrete steel cage, thereby heating the inside and surface of the concrete, and the electric heating wire directly heats the concrete surface; the temperature difference between the core and the surface of the concrete casting body is monitored by a temperature transmitter, and the power of the electric heating wire and the electromagnetic induction coil is adjusted according to the surface temperature difference, so that the temperature difference between the core and the surface of the concrete casting body is always maintained within the set surface temperature difference, thereby improving the early strength of the concrete, and before the curing and demolding are completed, the power of the electric heating wire and the electromagnetic induction coil is adjusted; the power of the electromagnetic induction coil is reduced in turn to control the cooling rate, and because the heat dissipation of the concrete surface is faster than that of the core, the temperature compensation can be performed through the electric heating wire, so that the concrete casting body adapts to the ambient temperature during the curing and demolding process, so that the temperature difference between the core and the surface of the concrete casting body, the cooling rate and the concrete strain rate meet the set requirements.

[0011] A method for curing heated formwork concrete for subway viaduct construction, using a heated formwork concrete curing system for subway viaduct construction, the method is specifically as follows: S1. Concrete pouring: Control the concrete pouring temperature so that the concrete pouring temperature is not lower than 5°C. When the ambient temperature is lower than -5°C, turn on the temperature control box to preheat the pouring formwork until the front temperature of the pouring formwork reaches 5°C. The pump truck can then pour concrete into the mold. After the concrete pouring is completed, the temperature control box is used to continuously perform the heat preservation and curing process. S2, concrete sealing. After the concrete is poured, the top and outer surfaces of the casting formwork are wrapped with thermal insulation cotton to seal and insulate the exposed surface of the poured concrete. The temperature of the concrete sealed inside is controlled and insulated by a temperature control box, so that the concrete in the casting formwork is hardened in a state of being isolated from the external environment. S3. Demolding of casting formwork: When the concrete in the casting formwork reaches the strength requirements of the acceptance standards and technical regulations and meets the requirements of frost resistance, the casting formwork is removed. Before removing the casting formwork, the temperature control box is controlled to continuously cool down the casting formwork so that the temperature difference between the concrete in the casting formwork and the environment is no more than 15°C.

[0012] Furthermore, when the temperature difference between the concrete in the casting formwork and the environment is greater than 10°C and less than 15°C, after the casting formwork is removed, the concrete surface needs to be temporarily covered with an insulation blanket.

[0013] Compared with the prior art, the heating formwork concrete curing system and curing method for subway viaduct construction of the present invention can be applied to bridges, railways, roads, tunnels, and buildings. The system completely abandons the traditional winter concrete construction method, no longer uses open fire to cause smoke and fire, no longer uses hot water to wet, and no longer uses boiler steam and tower sheds to build houses. The system adopts an electric heating method that integrates insulation and heating, and the entire construction and curing process is completed by electronic control; the system has low energy consumption, uniform temperature control, and accurate temperature adjustment of the construction site, and can be automatically controlled to reduce labor and energy consumption; it can not only carry out winter concrete construction to prevent concrete freezing damage, but also It can also meet the requirements of self-curing of concrete. Since the system is well sealed, no additional curing measures are required for the poured concrete, and its self-curing effect is equivalent to that of steam curing. At the same time, the early strength of concrete is improved, and the development of early strength exceeds the strength development in any other season's natural environment. Since this process is a physical method, the development of concrete's later strength will not be affected by the rapid development of early strength. In addition, this system can not only be used for concrete construction in winter, but also for large-volume concrete construction, or for construction of concrete in normal temperature environments that needs to improve its early strength, as well as for construction to prevent concrete cracking due to temperature differences. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 The present invention is a schematic diagram of the overall structure of the heating formwork concrete curing system for subway viaduct construction.

[0015] Figure 2 For the present invention Figure 1 Schematic diagram of the local enlarged structure at point A in the middle.

[0016] Figure 3 The present invention is a schematic diagram of the working process of the method for curing heated formwork concrete for subway viaduct construction.

[0017] Figure numerals: 1. casting formwork, 2. formwork back rib, 3. electric heating wire, 4. aluminum foil heat reflective film, 5. thermal insulation cotton, 6. pressing plate. DETAILED DESCRIPTION

[0018] Embodiment 1: like Figures 1 to 3 The heated formwork concrete curing system shown for subway viaduct construction includes A casting template 1, wherein template back ribs 2 are fixed at intervals on the back of the casting template 1; A heating module, wherein the heating module comprises an electric heating wire 3, which is fixedly attached to the back of the casting template 1 and arranged in the gap between the template back ribs 2, and the wiring spacing of the electric heating wire 3 on the casting template 1 is 300 mm; The heat insulation module includes an aluminum foil heat reflective film 4, which is pasted in the gap between the template back ribs 2 and wrapped around the back of the electric heating wire 3; the aluminum foil heat reflective film 4 is pressed with a heat insulation cotton 5 on the side away from the electric heating wire 3; the heat insulation cotton 5 is pressed with a pressing plate 6 on the side away from the aluminum foil heat reflective film 4; the pressing plate 6 is fixed to the inner surface of the template back rib 2; A temperature transmitter, which is installed on the back of the casting template 1, the concrete surface or the inside of the concrete; The temperature control box, the temperature transmitter is connected to the temperature control box; the electric heating wire 3 is connected to the temperature control box through a safety protector.

[0019] The heating formwork concrete curing system for subway viaduct construction of the present invention can insulate and seal the cast concrete, and perform electric heating and intelligent temperature control between the thermal insulation module and the concrete; during the concrete construction process, the concrete surface is sealed on the basis of the current construction process, and the concrete enclosed inside is temperature controlled and insulated, thereby achieving the hardening of the concrete in a state of isolation from the external environment during construction; information is collected by temperature transmitters arranged on the back of the casting formwork 1, the concrete surface and the inside of the concrete, and the information is sent to the temperature control box, which controls the electric heating line 3 through a set program to obtain real-time concrete construction conditions and intelligent information control.

[0020] The system installation process is as follows: clean the back of the casting template 1, remove oil stains and adhered concrete; then, paste the electric heating wire 3 and the temperature transmitter in the gap between the back ribs of the casting template 1, and paste the cut aluminum foil heat reflective film 4 on the casting template 1 behind the electric heating wire 3 according to the spacing of the template back ribs 2, so that the electric heating wire 3 is between the casting template 1 and the aluminum foil heat reflective film 4; according to the spacing size of the template back ribs 2, the appropriately cut insulation cotton 5 is installed in the gap between the template back ribs 2, and the back of the insulation cotton 5 is pressed with a pressing plate 6, and the pressing plate 6 is firmly fixed; finally, the electric heating wire 3 and the temperature transmitter are connected to the temperature control box.

[0021] After the concrete is poured and the surface is covered, the power supply of the temperature control box is connected to perform intelligent temperature control. When the temperature is low, in order to prevent freezing damage during the concrete pouring process, the formwork can be preheated for a period of time in advance. Before the device works, focus on checking whether the line is damaged, whether there are any leakage parts, whether the intelligent temperature control switch is intact, whether the leakage protection device is qualified, and whether the insulation of the line joints meets the requirements. Check whether there is any damage to the electric heating wire 3 during the construction process, especially the burning of the heating wire by electric welding during construction, which causes the heating wire and the formwork to stick together and leak. The fault must be eliminated, and a power-on test must be done before each use.

[0022] The temperature transmitter is also bonded to the front of the casting template 1 to complete the concrete surface temperature monitoring. When measuring the surface temperature of the concrete casting body, the temperature 50mm inside the concrete surface is used as the standard; and after the concrete is poured, the temperature transmitter is embedded in the concrete to complete the internal temperature monitoring of the concrete.

[0023] The casting template 1 is provided with a plurality of screw holes, and hollow bolts are screwed into the screw holes; a collection line passes through the hollow bolt and epoxy resin is poured; the collection line is connected to a temperature transmitter fixed on a steel cage of the concrete; the internal temperature of the concrete can be monitored through the temperature transmitter; after the casting is completed, the collection line can be directly cut off.

[0024] The electric heating wire 3 is composed of an electric heating wire and an electromagnetic induction coil; the electromagnetic induction coil is connected to an alternating current of appropriate size and frequency, which will generate an eddy current electromagnetic field in the casting template 1 and the concrete steel cage, thereby heating the inside and surface of the concrete, and the electric heating wire directly heats the concrete surface; the temperature difference between the core and the surface of the concrete casting body is monitored by a temperature transmitter, and the power of the electric heating wire and the electromagnetic induction coil is adjusted according to the surface temperature difference, so that the temperature difference between the core and the surface of the concrete casting body is always kept within the set surface temperature difference, thereby improving the early strength of the concrete, and before the curing and demoulding are completed, the power of the electric heating wire and the electromagnetic induction coil is adjusted; the power of the electromagnetic induction coil is reduced in turn to control the cooling rate, and because the heat dissipation of the concrete surface is faster than that of the core, the temperature compensation can be performed by the electric heating wire, so that the concrete casting body adapts to the ambient temperature during the curing and demoulding process, so that the temperature difference between the core and the surface of the concrete casting body, the cooling rate and the concrete strain rate meet the set requirements.

[0025] A method for curing heated formwork concrete for subway viaduct construction, and a system for curing heated formwork concrete for subway viaduct construction, wherein the method is specifically as follows: S1. Concrete is poured into the mold. The temperature of concrete pouring is controlled so that the temperature of concrete pouring into the mold is not lower than 5°C. When the ambient temperature is lower than -5°C, the temperature control box is turned on to preheat the pouring template 1 until the front temperature of the pouring template 1 reaches 5°C. The pump truck can then pour concrete into the mold. After the concrete pouring is completed, the temperature control box is used to continuously perform the thermal insulation and maintenance process. Before concrete pouring, thermal calculations and mixing station scheduling are performed, and the atmospheric environment temperature, mixing raw material temperature, silo temperature, and water temperature are tested. Test personnel test the concrete outlet temperature and the temperature of the concrete pouring into the mold. S2, concrete sealing, after the concrete is poured, the top surface and the outer surface of the casting template 1 are wrapped with thermal insulation cotton 5, and the exposed surface of the poured concrete is sealed and insulated; the temperature control box is used to control the temperature of the concrete enclosed inside and the temperature is insulated, so that the concrete in the casting template 1 is hardened in a state of being isolated from the external environment; S3. Demoulding of casting formwork 1. When the concrete in casting formwork 1 reaches the strength requirements of acceptance standards and technical regulations and meets the requirements of frost resistance, remove casting formwork 1. Before removing casting formwork 1, control the temperature control box to continuously cool down so that the temperature difference between the concrete in casting formwork 1 and the environment is not more than 15°C; check whether the concrete surface is frozen, bonded, shrunk and cracked, whether the edges and corners are falling off, and whether there are signs of freezing at the construction joints.

[0026] When the temperature difference between the concrete in the casting formwork 1 and the environment is greater than 10° C. and less than 15° C., after the casting formwork 1 is removed, the concrete surface needs to be temporarily covered with an insulation blanket.

[0027] The method for curing heated formwork concrete for subway viaduct construction of the present invention first conducts a concrete mixing process test before concrete pouring and curing in winter to obtain corresponding parameters to ensure the quality of concrete production in winter construction; and intermittently measures the temperature difference between the core and the surface of a large-volume concrete pouring body, the cooling rate, the ambient temperature and the strain.

[0028] The above embodiments are only preferred implementations of the present invention, so any equivalent changes or modifications made according to the structures, features and principles described in the scope of application of the present invention are included in the scope of application of the present invention.

Claims

1. A heating formwork concrete curing system for subway viaduct construction, characterized in that: include: A casting template, wherein template back ribs are fixed at intervals on the back of the casting template; A heating module, wherein the heating module comprises an electric heating wire, and the electric heating wire is adhered and fixed to the casting template between the back ribs of the template, and the wiring spacing of the electric heating wire on the casting template is 300 mm; A heat insulation module, the heat insulation module comprises an aluminum foil heat reflective film, the aluminum foil heat reflective film is pasted between the back ribs of the template and covers the electric heating wire, the aluminum foil heat reflective film is pressed with heat insulation cotton on the side facing outward, the heat insulation cotton is pressed with a pressing plate on the side facing outward, and the pressing plate is fixed to the inner surface of the back ribs of the template; A temperature transmitter, wherein the temperature transmitter is installed on the back of the casting formwork, the surface of the concrete or inside the concrete; The temperature control box, the temperature transmitter is connected to the temperature control box; the electric heating wire is connected to the temperature control box through a safety protector.

2. The heating formwork concrete curing system for subway viaduct construction according to claim 1 is characterized in that: The system installation process is as follows: clean the oil stains and adhered concrete on the back of the casting template; then, stick the electric heating wire and the temperature transmitter in the gap between the back ribs of the casting template, and stick the cut aluminum foil heat reflective film on the casting template at the electric heating wire according to the spacing of the back ribs of the template, so that the electric heating wire is between the casting template and the aluminum foil heat reflective film; according to the spacing size of the back ribs of the template, install the appropriately cut insulation cotton in the gap between the back ribs of the template, press the back of the insulation cotton with a pressing plate, and fix the pressing plate firmly; finally, connect the electric heating wire and the temperature transmitter to the temperature control box.

3. The heating formwork concrete curing system for subway viaduct construction according to claim 1 is characterized in that: The temperature transmitter is also bonded to the front side of the casting template and embedded into the concrete after the concrete is cast.

4. The heating formwork concrete curing system for subway viaduct construction according to claim 1 is characterized in that: The casting template is provided with a plurality of screw holes, and hollow bolts are screwed into the screw holes; a collection line passes through the hollow bolts and is poured with epoxy resin; the collection line is connected to a temperature transmitter fixed on a steel cage of concrete.

5. The heating formwork concrete curing system for subway viaduct construction according to claim 1 is characterized in that: The electric heating wire comprises an electric heating wire and an electromagnetic induction coil.

6. A method for curing heated formwork concrete for subway viaduct construction, using the heated formwork concrete curing system for subway viaduct construction as claimed in any one of claims 1 to 3, characterized in that: The method is specifically as follows: S1. Concrete is poured into the mold. The temperature of concrete pouring is controlled so that it is not lower than 5°C. When the ambient temperature is lower than -5°C, the temperature control box is turned on to preheat the pouring formwork. When the temperature on the front of the pouring formwork reaches 5°C, the pump truck pours concrete into the mold. After the concrete pouring is completed, the temperature control box is used to continuously perform the thermal insulation and maintenance process. S2, concrete sealing. After the concrete is poured, the top and outer surfaces of the pouring formwork are wrapped with thermal insulation cotton to seal and insulate the exposed surface of the poured concrete, and the temperature of the concrete enclosed inside is controlled and insulated by a temperature control box; S3. Demolding of casting formwork. When the concrete in the casting formwork reaches the strength requirement, the casting formwork is removed. Before removing the casting formwork, the temperature control box is controlled to continuously cool down the casting formwork so that the temperature difference between the concrete in the casting formwork and the environment is not more than 15°C.

7. The method for curing heated formwork concrete for subway viaduct construction according to claim 6 is characterized in that: When the temperature difference between the concrete in the casting formwork and the environment is greater than 10°C and less than 15°C, after the casting formwork is removed, a thermal insulation blanket is covered on the concrete surface.

Images