Temperature monitoring device for hydration heat stage of mass concrete structure

Abstract

The utility model discloses a temperature monitoring device for a hydration heat stage of a mass concrete structure, which comprises a thermodetector, the thermodetector is connected with a plurality of leads, and the tail end of each lead is provided with a temperature sensing probe; the monitoring device comprises an upper steel pipe bound with a reinforcement cage of a concrete structure, a plurality of positioning holes are formed in the side wall of the upper steel pipe in a penetrating mode, the positioning holes are in one-to-one correspondence with the measuring point positions, all wires are led into a pipe cavity from an opening in one end of the upper steel pipe, and each wire extends to the corresponding measuring point position along the pipe cavity of the upper steel pipe and is led out through the corresponding positioning hole; a protective shell is arranged outside each temperature sensing probe, a nylon rope is fixed at the lower end of each protective shell, all the nylon ropes are connected with a lower additional steel bar in a tensioning mode, and the lower additional steel bar is bound with a steel bar cage of a concrete structure. The monitoring device can resist pouring pressure and does not shift; reinforcing steel bar temperature is prevented from interfering with a temperature measurement result, temperature measurement point position accuracy is ensured, the number of residual anchoring objects is small, and the size is small.

Description

TECHNICAL FIELD

[0001] The utility model relates to the construction technical field of mass concrete structure, specifically is a mass concrete structure hydration heat stage temperature monitoring devices. BACKGROUND

[0002] The mass concrete structure referred to in the present application refers to the concrete structure whose minimum cross-sectional size exceeds 1 meter, such as concrete columns, concrete beams, etc. The mass concrete structure needs to be continuously monitored by a temperature monitoring device for its internal and external temperature difference during the hydration heat stage after pouring and before hardening, generally within 28 days after pouring. Because in the hydration heat process, the large-size concrete structure is prone to generate a large temperature difference stress due to uneven internal and external temperature distribution, causing cracking. Therefore, real-time monitoring is needed, and once the temperature difference exceeds the range, timely treatment is needed, such as pouring water into the concrete core through the pre-buried water pipe to reduce the temperature, or wrapping the outside with a thermal insulation layer, or winding a nylon rope to reduce the cooling rate and avoid excessive temperature difference cracking.

[0003] The temperature monitoring device includes a temperature meter, and the temperature meter is connected with a plurality of wires. The most conventional method in the construction site is to add an additional steel bar to the monitored cross-section of the concrete structure, bind the additional steel bar with the steel cage of the concrete structure, and then bind each wire on the corresponding point of the additional steel bar, such as binding a wire every 20 cm, and the end segment of each wire, i.e. the segment beyond the binding point, freely hangs with the temperature sensing probe.

[0004] The above-mentioned traditional monitoring device has a series of defects. First, during concrete pouring, each temperature sensing probe will be pushed by the pouring pressure, deviating from the original point, and cannot accurately measure the temperature of each measuring point. Moreover, the downward pouring concrete will impact the temperature sensing probe, downwardly pull and damage the wire, making it invalid. In actual situations, there have even been cases where only 7 out of 10 temperature sensing probes can work normally after pouring. Furthermore, with the impact of concrete or the rise of liquid surface, the temperature sensing probe will be lifted, making it abut against the steel bar. The steel bar and the concrete have a significant temperature difference, which will greatly interfere with the temperature measurement accuracy. In addition, the process of winding and binding the wire is complicated, and workers need to bind and wind each wire, and the binding points are not necessarily accurate each time.

[0005] Of course, to overcome the above drawbacks, some in the industry have proposed upgrade solutions, such as setting up an insulating bracket with its base resting on the ground or bottom formwork, and fixing the temperature sensor to the top of the bracket; or setting a protective shell around each temperature sensor and fixing a U-shaped buckle to the outside of the protective shell, with the U-shaped buckle snapping into the corresponding point of the additional reinforcing steel. However, the above upgrade solutions are not very practical and have little value for widespread application; for example, the structure of the insulating bracket is complex and large, which increases costs. More importantly, after pouring, the large volume of the insulating bracket remains anchored in the concrete, which will encroach on the concrete space and reduce the strength of the structure; and the problem with the snap-on structure is that it will cause the temperature sensor and the protective shell to be too close to the reinforcing steel, resulting in the temperature measurement results being significantly interfered with by the reinforcing steel and becoming inaccurate. Utility Model Content

[0006] The technical problem to be solved by this utility model is to provide a temperature monitoring device for the hydration heat stage of large-volume concrete structures that can withstand pouring pressure, does not shift, ensures that the conductor and the reinforcing bar maintain a reasonable distance, avoids the temperature measurement result being affected by the temperature of the reinforcing bar, ensures accurate temperature measurement points, and has a small number and volume of residual anchoring materials.

[0007] The technical solution of this utility model is to provide a temperature monitoring device for the hydration heat stage of a large-volume concrete structure. It includes a thermometer connected to multiple wires, each wire having a temperature-sensing probe at its end. The monitoring device includes an upper steel pipe tied to the reinforcing cage of the concrete structure. Multiple positioning holes are drilled through the side wall of the upper steel pipe, each corresponding to a measurement point. All wires are introduced into the pipe cavity from an opening at one end of the upper steel pipe, extending along the pipe cavity to the corresponding measurement point and exiting through the corresponding positioning hole. Each temperature-sensing probe is covered by a protective shell, with a nylon rope fixed to the lower end of each protective shell. All nylon ropes are tensioned and connected to a lower auxiliary reinforcing bar, which is also tied to the reinforcing cage of the concrete structure.

[0008] Compared with existing technologies, the monitoring device with the above structure has the following advantages.

[0009] First, each temperature sensor is secured between the upper steel pipe and the lower auxiliary reinforcing bar by a wire and nylon rope, thus resisting the pouring pressure and preventing displacement due to impact, allowing for accurate temperature measurement at each point. Furthermore, most of the wire is encased within the upper steel pipe cavity, protected from the impact of pouring pressure, while the wire ends extending from the positioning holes remain vertical, minimizing the impact and pulling force from the poured concrete. Because the temperature sensor is secured vertically, it does not float on the surface of the pouring liquid, remaining at the midpoint between the upper steel pipe and the lower auxiliary reinforcing bar, maintaining sufficient distance from nearby reinforcing bars and avoiding contact with any other reinforcing bar. The cold bridge effect of the reinforcing steel ensures that the temperature sensor is completely encased in concrete, thus accurately measuring the concrete temperature. Furthermore, the assembly process is quick and easy; only the upper steel pipe and lower additional reinforcing steel need to be fixed, and the wires leading from the positioning holes are essentially positioned above the measurement point, eliminating the need to tie each wire individually. Additionally, there is minimal residue left in the concrete after pouring. The upper steel pipe and lower additional reinforcing steel are anchored within the concrete as part of the structural reinforcement cage, further enhancing the concrete strength. Only nylon rope remains as anchorage, but this residue is minimal, small in size, and does not occupy internal concrete space, thus not reducing the structure's strength.

[0010] Preferably, each protective shell has a conical surface at the top. Since the temperature sensor and the protective shell are tied vertically by wires and nylon ropes, the conical surface at the top of the protective shell can significantly reduce the pulling impact of concrete on the protective shell and wires during pouring, preventing the wires from being pulled and damaged, and improving the working stability of the monitoring device.

[0011] As an enhancement, a rubber ring is fitted onto each wire, which is squeezed into the gap between the wire and the wall of the corresponding positioning hole. This allows for quick locking of the length of each wire's end extending out of the upper steel pipe positioning hole, ensuring that the ends of each wire are basically flush. This ensures that all temperature sensors are located on the same plane, i.e., the cross-section to be measured, and also ensures that the lower end of the nylon rope is basically flush, facilitating the assembly of additional reinforcing bars.

[0012] As a further optimization, each nylon rope has a loop at its lower end, and all nylon ropes are fitted with the lower additional reinforcing bars through their respective loops. This allows for quick and convenient connection of the lower additional reinforcing bars to the lower ends of each nylon rope, further simplifying the assembly process.

[0013] As another preferred option, each conductor has a protruding elastic limiting ring fixed at its end, which is smaller at the bottom and larger at the top. Each nylon rope has a knot at its upper end. Each protective shell is formed by screwing together an upper shell and a lower shell. The limiting ring is locked at the upper opening of the upper shell, and the knot is locked at the lower opening of the lower shell. The above structure makes assembly simpler. It is only necessary to force the elastic limiting ring through the upper opening of the upper shell, put the lower end of the nylon rope loop around the lower additional steel bar, and screw the upper shell and the lower shell together. Moreover, the above-mentioned threaded connection method also has a certain adjustment margin, which makes it easy to adjust the tension of the conductor and the nylon rope, thereby compensating for the assembly error of each conductor, nylon rope and temperature sensor. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the temperature monitoring device for the hydration heat stage of a large-volume concrete structure according to this utility model.

[0015] Figure 2 yes Figure 1 A magnified structural diagram of part A in the middle.

[0016] Figure 3 This is a schematic diagram of the installation of the temperature monitoring device of this utility model on a large-volume concrete column.

[0017] Figure 4 This is a schematic diagram of the temperature monitoring device of this utility model installed on a large-volume concrete beam.

[0018] The diagram shows: 1. Conductor, 2. Temperature sensor, 3. Upper steel pipe, 4. Protective shell, 4.1. Upper shell, 4.2. Lower shell, 5. Limiting ring, 6. Nylon rope, 7. Lower additional reinforcing bar, 8. Loop, 9. Concrete column, 10. Stirrup, 11. Concrete beam, 12. Horizontal main reinforcement. Detailed Implementation

[0019] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0020] like Figures 1 to 4 As shown, this utility model discloses a temperature monitoring device for the hydration heat stage of large-volume concrete structures. It includes a thermometer connected to multiple wires 1, with a temperature-sensing probe 2 at the end of each wire 1. Construction workers will number each wire 1 and each measurement point, so that each wire 1 corresponds to the same numbered measurement point.

[0021] The monitoring device includes an upper steel pipe 3 tied to a reinforcing cage of a concrete structure. Multiple positioning holes are drilled through the side wall of the upper steel pipe 3, each corresponding to a measurement point. For example, a positioning hole is opened every 20 cm along the pipe wall. All conductors 1 are introduced into the pipe cavity from an opening at one end of the upper steel pipe 3. Each conductor 1 extends along the pipe cavity to above the corresponding measurement point and exits the pipe cavity through the corresponding positioning hole. A rubber ring is fitted onto each conductor 1, and this rubber ring is inserted into the gap between the conductor 1 and the wall of the corresponding positioning hole; thus locking the length of the end of each conductor 1 extending beyond the positioning hole, ensuring that the ends of each conductor 1 and each temperature sensor 2 are essentially flush.

[0022] Each temperature sensor 2 is fitted with a protective shell 4, which is formed by screwing together an upper shell 4.1 and a lower shell 4.2. Each wire 1 has a protruding elastic retaining ring 5 fixed to its end. This retaining ring 5 is smaller at the bottom and larger at the top, designed to force its way past the upper opening of the upper shell 4.1, thus locking the upper opening of the upper shell 4.1 and achieving height-wise positioning between the two. The retaining ring 5 is made of elastic rubber material and is heat-fused, interference-fitted, or bonded to the sidewall of the wire. Each protective shell 4 has a conical surface at its top, i.e., the top of the upper shell 4.1.

[0023] Each protective shell 4 has a nylon rope 6 fixed to its lower end, with a knot 6.1 at the upper end of each rope 6, which secures the lower opening of the lower shell 4.2. All nylon ropes 6 are tensioned and connected to a lower auxiliary reinforcing bar 7, with a loop 8 at the lower end of each rope 6, and all ropes 6 are connected to the lower auxiliary reinforcing bar 7 via their respective loops 8. The lower auxiliary reinforcing bar 7 is also tied to the reinforcing cage of the concrete structure.

[0024] The monitoring device in this application is mainly installed inside a large-volume concrete column 9 or a large-volume concrete beam 11. Specifically, when monitoring the large-volume concrete column 9, such as... Figure 3 The upper steel pipe 3 and the lower additional reinforcing bar 7 of the monitoring device are respectively tied to the upper and lower adjacent stirrups 10 of the column reinforcement cage. When monitoring the large-volume concrete beam 11, if... Figure 4 The upper steel pipe 3 of the monitoring device is tied to the two transverse main bars 12 of the upper layer of the crossbeam 11 steel cage, while the lower additional steel bars 7 are tied to the two transverse main bars 12 of the lower layer of the crossbeam 11 steel cage.

[0025] Based on the patterns observed by the applicant during long-term construction, the most prone area to cracking in large-volume concrete columns is generally the middle plane of the column's height. Therefore, monitoring the internal and external temperature differences due to hydration heat at this middle plane is usually sufficient. Similarly, when pouring large-volume concrete beams 11, monitoring is also conducted on the middle plane of the beam's length, which is most susceptible to cracking. Of course, the construction party can also monitor multiple sections based on the actual conditions of the construction site, such as installing three sets of the monitoring devices described in this application at the left and right ends and the middle section of the beam 11 to monitor all three sections.

[0026] After 28 days of monitoring the section under test, the hollow upper steel pipe 3 needs to be filled with grout to further ensure the strength of the large-volume concrete structure.

Claims

1. A temperature monitoring device for the hydration heat stage of a large-volume concrete structure, comprising a thermometer connected to multiple wires, each wire having a temperature sensing probe at its end; characterized in that: The monitoring device includes an upper steel pipe tied to the reinforcing cage of the concrete structure. Multiple positioning holes are penetrating the side wall of the upper steel pipe, and each positioning hole corresponds to a measurement point. All wires are introduced into the pipe cavity from an opening at one end of the upper steel pipe. Each wire extends along the pipe cavity to the corresponding measurement point and is led out through the corresponding positioning hole. Each temperature sensor is equipped with a protective shell, and a nylon rope is fixed to the lower end of each protective shell. All nylon ropes are tensioned and connected to a lower additional reinforcing bar, which is also tied to the reinforcing cage of the concrete structure.

2. The temperature monitoring device for the hydration heat stage of a large-volume concrete structure according to claim 1, characterized in that: Each protective shell has a conical surface at the top.

3. The temperature monitoring device for the hydration heat stage of a large-volume concrete structure according to claim 1, characterized in that: Each wire is fitted with a rubber ring, which is squeezed into the gap between the wire and the wall of the corresponding positioning hole.

4. The temperature monitoring device for the hydration heat stage of a large-volume concrete structure according to claim 3, characterized in that: Each nylon rope has a loop at its lower end, and all nylon ropes are connected to the additional reinforcing steel bars through their respective loops.

5. The temperature monitoring device for the hydration heat stage of a large-volume concrete structure according to claim 1, characterized in that: Each conductor has a protruding elastic limiting ring fixed at its end, which is smaller at the bottom and larger at the top. Each nylon rope has a knot at its upper end. Each protective shell is formed by screwing together an upper shell and a lower shell. The limiting ring locks the upper opening of the upper shell, and the knot locks the lower opening of the lower shell.

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