A mass concrete construction method based on crack control

Abstract

The present invention provides a large-volume concrete construction method based on crack control, by installing a thermosensitive cavity in the middle of a steel cage, using an electric heating matrix and an electric heating wire mesh to control the temperature of the concrete to reduce the generation of cracks; the thermosensitive cavity is surrounded by a steel plate, and is equipped with an electric heating matrix, an electric heating wire mesh and a heat-conducting steel frame, and is connected to an external power supply and a controller through a cable. During construction, the temperature difference between the inside and outside of the concrete is monitored by a temperature sensor, and the heating and insulation of the thermosensitive cavity are controlled according to the temperature difference, effectively reducing the risk of cracks caused by hydration heat and environmental temperature difference. This method improves construction efficiency and ensures the safety and durability of concrete structures.

Description

Technical Field

[0001] The invention relates to the technical field of mass concrete quality control, and in particular to a mass concrete construction method based on crack control. Background Art

[0002] In the field of mass concrete construction, crack control has always been a major challenge faced by engineering technicians. Mass concrete generates a large amount of hydration heat during the hardening process, resulting in a significant temperature gradient inside the concrete, which in turn causes cracks. In addition, changes in external ambient temperature can also affect the curing quality of concrete, which may cause the curing moisture to condense and affect the strength development of concrete. Traditional mass concrete construction methods often have difficulty in effectively controlling these temperature differences, thereby increasing the risk of structural cracks.

[0003] In the prior art, in order to reduce cracks in large-volume concrete, the following methods are usually used: first, adding expansion agents to concrete to offset shrinkage stress through concrete expansion; second, using block casting to reduce the temperature gradient inside the concrete; third, setting cooling water pipes inside the concrete to reduce the temperature of the concrete through circulating water. However, these methods have certain limitations. For example, adding expansion agents may affect the strength and durability of concrete, block casting has low construction efficiency and is difficult to ensure the uniformity of the overall structure, and the setting of cooling water pipes increases construction costs and complexity.

[0004] In view of the above problems, technicians in this field have conducted a lot of research and exploration to seek more effective crack control methods. Although certain progress has been made, there is still a lack of a construction method that can control the temperature of large-volume concrete in real time during construction to effectively prevent cracks. Therefore, developing a large-volume concrete construction method based on crack control, which can monitor and adjust the internal temperature of concrete in real time to reduce cracks caused by temperature differences, has become a technical problem that needs to be solved in this field. Summary of the invention

[0005] In order to solve the above problems, the present invention proposes a mass concrete construction method based on crack control, which is implemented by the following technical solutions:

[0006] A mass concrete construction method based on crack control, wherein a thermally sensitive cavity is installed in the middle of a mass concrete steel cage when tying the mass concrete steel cage, wherein the thermally sensitive cavity has a closed cubic steel plate skeleton surrounded by six steel plates, wherein the thermally sensitive cavity comprises an electric heating matrix, an electric heating wire mesh, a steel plate inner cavity and a heat-conducting steel frame, wherein the electric heating matrix is ​​arranged in the steel plate inner cavity and heats the steel plate inner cavity, and the heat-conducting steel frame is used to transfer the heat of the steel plate inner cavity to the interior of the mass concrete; the thermally sensitive cavity is connected to the outside through a cable, and is located on the surface, interior and exterior of the mass concrete. A temperature sensor is provided inside the thermosensitive cavity to obtain the temperature difference t0 between the inside and outside of the large volume of concrete. The thermosensitive cavity performs temperature heating and insulation control by obtaining the temperature difference t0 between the inside and outside of the large volume of concrete. After the installation of the thermosensitive cavity is completed, the large volume of concrete is sealed, and then the concrete is poured in layers. When the concrete submerges any part of the structure of the heat-conducting steel frame, the thermosensitive cavity starts temperature control work. After all the concrete is poured, the thermosensitive cavity performs maintenance temperature control work. After the concrete curing is completed, the thermosensitive cavity performs temperature control work for crack control.

[0007] Furthermore, the heat-conducting steel bar frame includes six heat-conducting steel bars, one end of which is inserted into the steel plate frame and welded to the steel plate, extending into the steel plate for a distance, and the other end is arranged at the midpoint of the straight-line distance between the corresponding side of the large volume concrete and the nearest steel plate, and a heat-conducting sheet for diffusing heat is arranged at its end, wherein the top and bottom heat-conducting steel bars are respectively welded to the top steel plate and the bottom steel plate of the electric heating matrix after being inserted into the corresponding steel plates.

[0008] Furthermore, the electric heating matrix includes a top steel plate and a bottom steel plate, and ceramic heating tubes arranged in a matrix are connected between the top steel plate and the bottom steel plate. The ceramic heating tubes are vertically arranged, and all the ceramic heating tubes are connected in parallel. The electric heating matrix is ​​connected to an external power supply and an external controller through a power cable and a control cable respectively. The external controller can issue a heating instruction and a heating stop instruction to the electric heating matrix. The outer sides of the top steel plate and the bottom steel plate are connected and fixed to a heat-conducting steel frame.

[0009] Furthermore, the electric heating wire mesh has six pieces, which are respectively attached to the inner side of the steel plate frame to form a closed structure. All the electric heating wire meshes are connected in parallel. The electric heating wire meshes are connected to the external power supply and the external controller through the power cable and the control cable respectively. The external controller can issue insulation instructions and insulation stop instructions to the electric heating wire mesh.

[0010] Furthermore, a pre-buried wire tube is provided, one end of which is connected to the side of the thermistor cavity and the other end extends out of the outer surface of the side of the massive concrete. All cables are connected to the outside through the pre-buried wire tube. The elevation of the end of the pre-buried wire tube connected to the thermistor cavity is higher than the elevation of the end extending out of the outer surface of the side of the massive concrete, and the specific slope is 2‰ to 5‰.

[0011] Furthermore, the temperature control work includes: obtaining the temperature difference t0 of the internal and external mass concrete in real time based on a preset temperature sensor, including the following steps: obtaining the temperature t1 of the built-in thermosensitive cavity based on a temperature sensor preset inside the thermosensitive cavity; obtaining the temperature of the external environment based on a temperature sensor preset on the surface of the mass concrete, and averaging the temperatures obtained by all temperature sensors to obtain the temperature t2 of the external environment; obtaining the internal concrete temperature based on a temperature sensor preset inside the mass concrete, and averaging the temperatures obtained by all temperature sensors to obtain the internal concrete temperature t3; obtaining the temperature difference t0 of the internal and external mass concrete through the formula t0=t3-t2.

[0012] Further, the temperature control work includes: a control method for controlling the temperature of the mass concrete based on the temperature difference t0 between the inner and outer mass concrete, comprising the following steps:

[0013] (1) When the temperature difference t0 between the inner and outer mass concrete is greater than or equal to 10 degrees, and at the same time, the temperature t1 of the built-in thermosensitive cavity is less than the internal concrete temperature t3, the external controller sends a temperature increase command to the electric heating matrix and a heat preservation stop command to the electric heating wire mesh. The electric heating matrix conducts heat to the heat-conducting steel bars in six directions and evenly diffuses the heat through the heat-conducting sheet, so that the temperature difference t0 between the inner and outer mass concrete is reduced;

[0014] (2) When the temperature difference t0 between the inner and outer mass concrete is less than 10 degrees, and at the same time the temperature t1 of the built-in thermistor cavity is less than the internal concrete temperature t3, the external controller sends a temperature rise stop command to the electric heating matrix and a heat preservation command to the electric heating wire mesh. The electric heating wire mesh conducts heat to the steel plate skeleton, and part of it can be conducted to the heat-conducting steel bars in six directions. The heat is evenly diffused through the steel plate skeleton and the heat-conducting sheet, so that the temperature difference t0 between the inner and outer mass concrete remains constant.

[0015] The mass concrete construction method based on crack control of the present invention has the following significant beneficial effects:

[0016] (1) By setting up a thermosensitive inner cavity with a temperature sensor, the temperature of the mass concrete can be controlled in real time, eliminating the problem of cracks caused by the temperature difference inside the concrete due to the hydration heat generated when the mass concrete hardens. At the same time, it ensures that the mass concrete is not effectively cured due to the condensation of the curing moisture caused by the low external ambient temperature during curing, which further reduces the risk of cracks caused by thermal expansion and contraction of the mass concrete during the entire use process.

[0017] (2) The steel plate skeleton and heat-conducting steel frame structure make up for the large concrete steel structure, so that the thermal sensitive inner cavity can be used as a steel skeleton of the large concrete, occupying a small and concentrated space, greatly reducing the risk of evenly arranging the heating elements in the large concrete to affect the quality of the large concrete.

[0018] (3) The use of an electric heating matrix can improve the efficiency of electric heating while ensuring the temperature increase efficiency inside the entire thermistor cavity. The heat can be quickly transferred to the middle of the large volume of concrete through the heat-conducting steel bars and heat-conducting sheets to achieve precise control of the temperature increase, and the heat can be evenly diffused to achieve the overall temperature increase of the large volume of concrete, eliminating the damage caused by the large local temperature difference inside the large volume of concrete.

[0019] (4) The use of electric heating wire mesh insulation can ensure that heat is evenly diffused to the surrounding concrete, and can achieve insulation function during concrete pouring, curing, and use, avoiding concrete cracks caused by temperature differences during any of the pouring, curing, and use processes, making the crack control effect of the thermal sensitive inner cavity last longer. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the implementation modes of the present application, the drawings required for use in the description of the implementation modes will be briefly introduced below. Obviously, the drawings described below are only some implementation modes of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0021] Figure 1 It is a schematic diagram of the structure of the present invention.

[0022] Figure 2 It is a schematic diagram of the internal structure of the present invention.

[0023] Figure 3 It is a schematic diagram of the internal structure of the thermosensitive cavity of the present invention.

[0024] Figure 4 Schematic diagram of the distribution structure of the invented electric heating wire mesh.

[0025] Description of reference numerals:

[0026] 100-thermal sensitive cavity, 101-electric heating matrix, 102-electric heating wire mesh, 103-steel plate skeleton, 104-heat conductive steel bar frame, 105-heat conductive steel bar, 106-heat conductive sheet, 107-top steel plate, 108-bottom steel plate, 109-ceramic heating tube, 110-buried wire tube, 111-external power supply, 112-external controller. DETAILED DESCRIPTION

[0027] The following description of the embodiments will help the public better understand the present invention, but the specific embodiments given by the applicant cannot and should not be regarded as limitations on the technical solutions of the present invention. Any changes to the definitions of components or technical features, or formal rather than substantive changes to the overall structure should be regarded as the scope of protection defined by the technical solutions of the present invention.

[0028] In this application, unless otherwise clearly specified or limited, the terms "installation", "connection", "fixation" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be internal communication between two elements, or it can be only surface contact, or surface contact connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0029] Embodiment 1:

[0030] See also Figure 1 A large-volume concrete construction method based on crack control, wherein a thermal-sensitive cavity 100 is installed in the middle of a large-volume concrete steel cage when tying the large-volume concrete steel cage, and after the installation of the thermal-sensitive cavity 100 is completed, the large-volume concrete is sealed, and then the concrete is poured in layers. When the concrete submerges any part of the structure of the heat-conducting steel frame 104, the thermal-sensitive cavity 100 starts temperature control work, and after all the concrete pouring is completed, the thermal-sensitive cavity 100 performs maintenance temperature control work, and after the concrete curing is completed, the thermal-sensitive cavity 100 performs temperature control work for crack control.

[0031] See also Figure 2 The thermosensitive cavity 100 has a closed cubic steel plate skeleton 103 surrounded by six steel plates. The thermosensitive cavity 100 includes an electric heating matrix 101, an electric heating wire mesh 102, a steel plate inner cavity and a heat-conducting steel frame 104.

[0032] See also Figure 1 and Figure 3The electric heating matrix 101 includes a top steel plate 107 and a bottom steel plate 108, between which are connected ceramic heating tubes 109 arranged in a matrix, the ceramic heating tubes 109 are vertically arranged, and all ceramic heating tubes 109 are connected in parallel. The electric heating matrix 101 is connected to an external power supply 111 and an external controller 112 through a power cable and a control cable respectively, and the external controller 112 can issue a temperature increase instruction and a temperature increase stop instruction to the electric heating matrix 101. The outer sides of the top steel plate 107 and the bottom steel plate 108 are It is connected and fixed to a heat-conducting steel bar frame 104; the heat-conducting steel bar frame 104 includes six heat-conducting steel bars 105, one end of which is inserted into the steel plate skeleton 103 and welded to the steel plate, extending into the steel plate for a distance, and the other end is arranged at the midpoint of the straight-line distance between the corresponding side surface of the large volume concrete and the nearest steel plate, and a heat-conducting sheet 106 for diffusing heat is arranged at its end, wherein the top and bottom heat-conducting steel bars 105 are respectively welded to the top steel plate 107 and the bottom steel plate 108 of the electric heating matrix 101 after being inserted into the corresponding steel plates.

[0033] See also Figure 4 The electric heating wire mesh 102 has six pieces, which are respectively attached to the inner side of the steel plate frame 103 to form a closed structure. All the electric heating wire meshes 102 are connected in parallel. The electric heating wire mesh 102 is connected to the external power supply 111 and the external controller 112 through a power cable and a control cable respectively. The external controller 112 can issue insulation instructions and insulation stop instructions to the electric heating wire mesh 102.

[0034] A pre-buried wire tube 110 is provided, one end of which is connected to the side of the thermosensitive cavity 100, and the other end extends out of the outer surface of the side of the massive concrete. All cables are connected to the outside through the pre-buried wire tube 110. The elevation of one end of the pre-buried wire tube 110 connected to the thermosensitive cavity 100 is higher than the elevation of the other end extending out of the outer surface of the side of the massive concrete, and the specific slope is 2‰ to 5‰.

[0035] The electric heating matrix 101 is arranged in the inner cavity of the steel plate and heats the inner cavity of the steel plate. The heat-conducting steel bar frame 104 is used to transfer the heat of the inner cavity of the steel plate to the interior of the mass concrete. The thermosensitive cavity 100 is connected to the outside through a cable. Temperature sensors are arranged on the surface and the interior of the mass concrete and inside the thermosensitive cavity 100 to obtain the temperature difference t0 between the inner and outer mass concrete. The thermosensitive cavity 100 performs temperature heating and heat preservation control by obtaining the temperature difference t0 between the inner and outer mass concrete.

[0036] The temperature control work includes: obtaining the temperature difference t0 of the internal and external mass concrete in real time based on the preset temperature sensor, including the following steps: obtaining the temperature t1 of the built-in thermosensitive cavity 100 based on the preset temperature sensor inside the thermosensitive cavity 100; obtaining the temperature of the external environment based on the preset temperature sensor on the surface of the mass concrete, and taking the average temperature obtained by all temperature sensors to obtain the temperature t2 of the external environment; obtaining the internal concrete temperature based on the preset temperature sensor inside the mass concrete, and taking the average temperature obtained by all temperature sensors to obtain the internal concrete temperature t3; obtaining the temperature difference t0 of the internal and external mass concrete through the formula t0=t3-t2.

[0037] The method for controlling the temperature of mass concrete based on the temperature difference t0 between the inner and outer mass concrete comprises the following steps:

[0038] (1) When the temperature difference t0 between the inner and outer mass concrete is greater than or equal to 10 degrees, and at the same time, the temperature t1 of the built-in thermosensitive cavity 100 is less than the internal concrete temperature t3, the external controller 112 sends a temperature increase instruction to the electric heating matrix 101 and a heat preservation stop instruction to the electric heating wire mesh 102. The electric heating matrix 101 conducts heat to the heat-conducting steel bars 105 in six directions and evenly diffuses the heat through the heat-conducting sheet 106, so that the temperature difference t0 between the inner and outer mass concrete is reduced;

[0039] (2) When the temperature difference t0 between the inner and outer mass concrete is less than 10 degrees, and at the same time the temperature t1 of the built-in thermistor cavity 100 is less than the internal concrete temperature t3, the external controller 112 sends a temperature increase stop command to the electric heating matrix 101 and a heat preservation command to the electric heating wire mesh 102. The electric heating wire mesh 102 conducts heat to the steel plate skeleton 103, and part of the heat can be conducted to the heat-conducting steel bars 105 in six directions, and the heat is evenly diffused through the steel plate skeleton 103 and the heat-conducting sheet 106, so that the temperature difference t0 between the inner and outer mass concrete remains constant.

[0040] Those skilled in the art should understand that those skilled in the art can implement variations by combining the prior art and the above embodiments, which will not be described in detail here. Such variations do not affect the essential content of the present invention, and will not be described in detail here.

[0041] The above describes the preferred embodiments of the present invention. It should be understood that the present invention is not limited to the above-mentioned specific embodiments, and the devices and structures that are not described in detail should be understood to be implemented in a common manner in the art; any technician familiar with the art can use the above-disclosed methods and technical contents to make many possible changes and modifications to the technical solutions of the present invention without departing from the scope of the technical solutions of the present invention, or modify them into equivalent embodiments of equivalent changes, which does not affect the essential content of the present invention. Therefore, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solutions of the present invention are still within the scope of protection of the technical solutions of the present invention.

Claims

1. A mass concrete construction method based on crack control, characterized in that: When tying a large-volume concrete steel cage, a thermosensitive cavity (100) is installed in the middle of the steel cage. The thermosensitive cavity (100) has a closed cubic steel plate frame (103) surrounded by six steel plates. The thermosensitive cavity (100) includes an electric heating matrix (101), an electric heating wire mesh (102), a steel plate inner cavity and a heat-conducting steel frame (104). The electric heating matrix (101) is arranged in the steel plate inner cavity and heats the steel plate inner cavity. The heat-conducting steel frame (104) is used to transfer the heat of the steel plate inner cavity to the interior of the large-volume concrete. The thermosensitive cavity (100) is connected to the outside through a cable and is located on the surface, interior and thermosensitive cavity of the large-volume concrete. A temperature sensor is arranged inside the cavity (100) for obtaining the temperature difference t0 between the inner and outer large-volume concrete. The thermosensitive cavity (100) performs temperature rise and heat preservation control by obtaining the temperature difference t0 between the inner and outer large-volume concrete. After the thermosensitive cavity (100) is installed, the large-volume concrete is sealed, and then the concrete is poured in layers. When the concrete submerges any part of the structure of the heat-conducting steel bar frame (104), the thermosensitive cavity (100) starts temperature control. After all concrete pouring is completed, the thermosensitive cavity (100) performs maintenance temperature control. After the concrete curing is completed, the thermosensitive cavity (100) performs temperature control for crack control.

2. A method for mass concrete construction based on crack control according to claim 1, characterized in that: The electric heating matrix (101) comprises a top steel plate (107) and a bottom steel plate (108), and ceramic heating tubes (109) arranged in a matrix are connected between the top steel plate (107) and the bottom steel plate (108). The ceramic heating tubes (109) are arranged vertically, and all the ceramic heating tubes (109) are connected in parallel. The electric heating matrix (101) is connected to an external power source (111) and an external controller (112) through a power cable and a control cable, respectively. The external controller (112) can issue a temperature increase instruction and a temperature increase stop instruction to the electric heating matrix (101). The outer sides of the top steel plate (107) and the bottom steel plate (108) are both connected and fixed to a heat-conducting steel bar frame (104).

3. A mass concrete construction method based on crack control according to claim 2, characterized in that: The electric heating wire mesh (102) has six pieces, which are respectively attached to the inner side of the steel plate frame (103) to form a closed structure. All the electric heating wire meshes (102) are connected in parallel. The electric heating wire mesh (102) is connected to an external power supply (111) and an external controller (112) through a power cable and a control cable respectively. The external controller (112) can issue a heat preservation instruction and a heat preservation stop instruction to the electric heating wire mesh (102).

4. A method for mass concrete construction based on crack control according to claim 2, characterized in that: The heat-conducting steel bar frame (104) includes six heat-conducting steel bars (105), one end of which is inserted into the steel plate frame (103) and welded to the steel plate, extending into the steel plate for a distance, and the other end is arranged at the midpoint of the straight-line distance between the corresponding side surface of the mass concrete and the nearest steel plate, and a heat-conducting sheet (106) for diffusing heat is arranged at the end thereof, wherein the top and bottom heat-conducting steel bars (105) are respectively welded to the top steel plate (107) and the bottom steel plate (108) of the electric heating matrix (101) after being inserted into the corresponding steel plate.

5. The method for mass concrete construction based on crack control according to claim 1, characterized in that: A pre-buried wire tube (110) is provided, one end of the pre-buried wire tube (110) is connected to the side of the thermosensitive cavity (100), and the other end extends out of the outer surface of the side of the large-volume concrete. All cables are connected to the outside through the pre-buried wire tube (110). The elevation of the end of the pre-buried wire tube (110) connected to the thermosensitive cavity (100) is higher than the elevation of the end extending out of the outer surface of the side of the large-volume concrete, and the specific slope is 2‰ to 5‰.

6. A method for mass concrete construction based on crack control according to claim 3, characterized in that: The temperature control operation comprises: obtaining the temperature difference t0 between the inner and outer mass concrete in real time based on a preset temperature sensor, and comprises the following steps: obtaining the temperature t1 of the built-in thermosensitive cavity (100) based on a preset temperature sensor inside the thermosensitive cavity (100); obtaining the temperature of the external environment based on a preset temperature sensor on the surface of the mass concrete, and taking the average of the temperatures obtained by all the temperature sensors to obtain the temperature t2 of the external environment; obtaining the internal concrete temperature based on a preset temperature sensor inside the mass concrete, and taking the average of the temperatures obtained by all the temperature sensors to obtain the internal concrete temperature t3; and obtaining the temperature difference t0 between the inner and outer mass concrete through the formula t0=t3-t2.

7. A method for mass concrete construction based on crack control according to claim 6, characterized in that: The temperature control work includes: a control method for controlling the temperature of the mass concrete based on the temperature difference t0 between the inner and outer mass concrete, including the following steps: (1) When the temperature difference t0 between the inner and outer mass concrete is greater than or equal to 10 degrees, and at the same time the temperature t1 of the built-in thermosensitive cavity (100) is less than the inner concrete temperature t3, the external controller (112) sends a temperature increase instruction to the electric heating matrix (101) and sends a heat preservation stop instruction to the electric heating wire mesh (102), and the electric heating matrix (101) conducts heat to the heat-conducting steel bars (105) in six directions, and evenly diffuses the heat through the heat-conducting sheet (106), so that the temperature difference t0 between the inner and outer mass concrete is reduced; (2) When the temperature difference t0 between the inner and outer mass concrete is less than 10 degrees, and at the same time the temperature t1 of the built-in thermosensitive cavity (100) is less than the inner concrete temperature t3, the external controller (112) sends a temperature rise stop command to the electric heating matrix (101) and sends a heat preservation command to the electric heating wire mesh (102). The electric heating wire mesh (102) conducts heat to the steel plate skeleton (103), and part of the heat can be conducted to the heat-conducting steel bars (105) in six directions, and the heat is evenly diffused through the steel plate skeleton (103) and the heat-conducting sheet (106), so that the temperature difference t0 between the inner and outer mass concrete remains constant.

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