A large-volume concrete test system and its construction method

Abstract

This invention discloses a large-volume concrete testing system and its construction method. The large-volume concrete testing system includes: a foundation pit with a trapezoidal excavation profile and a concrete cushion layer poured on the bottom surface; a formwork system comprising multiple evenly spaced vertically arranged I-beams, which enclose a concrete pouring space with a square cross-section, four pieces of glued laminated timber formwork fixedly connected to the inner side of the I-beams, and multiple double-channel steel bars spaced along the length of the outer side of the I-beams; a steel reinforcement support system disposed inside the concrete pouring space; a formwork support and fixing system comprising multiple formwork supports, one end of which is fixedly connected to the double-channel steel bars, and the other end of which is fixedly connected to the slope of the foundation pit; a temperature measurement system comprising multiple temperature sensors, which are arranged at different temperature measurement points inside the concrete pouring space via sensor-attached steel bars; and a thermal insulation system fixedly disposed inside the glued laminated timber formwork.

Description

Technical Field

[0001] This invention relates to the field of large-volume concrete construction technology, specifically to a large-volume concrete testing system and its construction method. Background Technology

[0002] In recent years, various high-rise and super high-rise buildings have sprung up, and their foundations often employ large-volume concrete foundations such as box foundations and raft foundations. The large volume of concrete required for continuous pouring results in a rapid rise in internal temperature due to the heat of hydration generated during this continuous pouring. Therefore, controlling the heat of hydration and internal temperature differences of large-volume concrete is one of the challenges in the foundation construction of high-rise and super high-rise buildings. Summary of the Invention

[0003] The purpose of this invention is to provide a large-volume concrete test system and its construction method, which can effectively simulate the internal temperature changes of large-volume concrete under the same conditions, avoid quality accidents such as temperature cracks and formwork bulging in the pouring of large-volume concrete in formal projects, and thus provide guidance for subsequent construction.

[0004] To achieve the above objectives, the present invention provides a large-volume concrete testing system, which is set underground. This system includes: a foundation pit with a trapezoidal excavation profile, comprising a foundation pit slope and a concrete cushion layer poured at the bottom; a formwork system comprising multiple evenly spaced vertically arranged I-beams, forming a square-section concrete pouring space; four glued laminated timber formwork panels fixedly connected to the inner side of each I-beam; and multiple double-channel steel bars spaced along the length of each I-beam; a steel reinforcement support system located inside the concrete pouring space; a formwork support and fixing system comprising multiple formwork supports, one end of which is fixedly connected to the double-channel steel bars, and the other end to the foundation pit slope; a temperature measurement system comprising multiple temperature sensors, which are attached to steel bars and positioned at different temperature measurement points inside the concrete pouring space; and an insulation system fixedly installed inside the glued laminated timber formwork.

[0005] In a preferred embodiment, the rebar support system includes protective layer blocks and rebar supports, with multiple protective layer blocks evenly spaced above the concrete foundation and the rebar supports positioned above the protective layer blocks.

[0006] In a preferred embodiment, the protective layer pads are arranged at 1m intervals along the horizontal and vertical directions, the steel reinforcement support includes vertical steel bars, and a horizontal reinforcing bar is provided at the top of the steel reinforcement support. The horizontal reinforcing bar is welded to the vertical steel bar. The steel reinforcement support is also provided with multiple horizontal structural steel bars and diagonal structural steel bars, which are welded to the vertical steel bars respectively.

[0007] In a preferred embodiment, the formwork support includes a steel pipe, an adjustable bottom support, and an adjustable top support. The adjustable bottom support and the adjustable top support are rotatably mounted on both ends of the steel pipe. The adjustable top support is supported on a double channel steel, and the adjustable bottom support is supported on the slope of the foundation pit. The formwork support fixing system is also provided with multiple layers of tie rods. The tie rods are located at the four corners of the glued laminated timber formwork, and the four glued laminated timber formwork pieces are connected into a whole through the tie rods.

[0008] In a preferred embodiment, four temperature measuring points are set, located at the end, middle, 1 / 4 of a diagonal of the concrete pouring space, and the midpoint of one of the side lines, respectively. Each temperature measuring point is equipped with a first temperature sensor, a second temperature sensor, a third temperature sensor, a fourth temperature sensor, and a temperature receiver arranged vertically. The first, second, third, and fourth temperature sensors are fixed to the sensor attachment steel bars and are respectively connected to the temperature receiver via data transmission lines. The first temperature sensor is 200mm from the top surface, the second temperature sensor is located at the center, the third temperature sensor is 200mm from the bottom surface, and the fourth temperature sensor is placed in the atmosphere.

[0009] In a preferred embodiment, the plywood formwork and the I-beams are fixedly connected by nails. Four double-channel steels are arranged vertically at intervals, with the distances between the four double-channel steels and the ground being 300mm, 1300mm, 2500mm, and 2900mm, respectively. The I-beams and the double-channel steels are connected by channel steel beam connecting fasteners. The height of the I-beams is 200mm, and the interval between two adjacent I-beams is 300mm.

[0010] The present invention also provides a construction method for the above-mentioned large-volume concrete test system, comprising the following steps:

[0011] S1. Excavation of the foundation pit;

[0012] S2. Pour the concrete foundation layer;

[0013] S3. Place concrete protective layer spacers. After the protective layer spacers are placed, process and place the steel reinforcement supports and steel mesh.

[0014] S4. Process the formwork system and hoist it into the foundation pit to create a space for concrete pouring.

[0015] S5. Erect a formwork support and fixing system, and connect the formwork support and fixing system to the formwork system and the foundation pit slope;

[0016] S6. Establish a temperature measurement system;

[0017] S7. Layered concrete pouring;

[0018] S8. After the concrete is poured, cover it with a plastic film, and then cover the plastic film with cotton felt for curing.

[0019] S9. Take temperature measurement;

[0020] S10, Demolding and backfilling;

[0021] S11. After the concrete pouring is completed, core samples are taken to measure the concrete strength.

[0022] In a preferred embodiment, step S4, processing the template system and hoisting the template system into the foundation pit, includes: first, nailing I-beams to the plywood template with nails on the ground near the foundation pit, with the I-beams placed vertically; then connecting double channel steel to the I-beams with channel steel beam connecting fasteners, with the double channel steel placed horizontally; after the plywood template, I-beams, and double channel steel are connected as a whole, the extruded polystyrene board is glued to the surface of the plywood template; after the four templates are processed, they are hoisted into the foundation pit through the lifting rings on the I-beams.

[0023] In step S5, the formwork support and fixing system is erected and connected to the formwork system and the foundation pit slope. This includes: First, four formwork panels are connected into a whole by tie rods. The tie rods are set at the four corners of the plywood formwork, with a total of 4 layers. The heights from the ground are 300mm, 1300mm, 2500mm and 2900mm respectively. After the tie rods are set, the formwork support is erected. The overall length of the formwork support is adjusted by rotating the adjustable bottom support and the adjustable top support. The adjustable top support is supported on the double channel steel, and the adjustable bottom support is supported on the foundation pit slope.

[0024] In a preferred embodiment, step S6, establishing the temperature measurement system includes: firstly, determining the positions of four temperature measurement points by laying out lines; fixing the first, second, third, and fourth temperature sensors to the sensor attachment steel bars and connecting them to the temperature receivers via data transmission lines; the first temperature sensor being 200mm from the top surface, the second temperature sensor being located in the center, the third temperature sensor being 200mm from the bottom surface, and the fourth temperature sensor being placed in the atmosphere; and tying the temperature receivers to the top of the sensor attachment steel bars with ropes. After fixing the temperature sensors, temperature receivers, and sensor attachment steel bars, the sensor attachment steel bars are placed at the four previously determined temperature measurement point positions.

[0025] Compared with existing technologies, the beneficial effects of this invention are as follows: To verify the rationality of concrete mix proportions and to provide guidance for subsequent raft foundation concrete formwork erection, temperature measurement, and curing processes, this invention forms a complete and reliable large-volume concrete testing system and its construction method. This testing system can effectively simulate the internal temperature changes of large-volume concrete under the same conditions, avoiding quality accidents such as temperature cracks and formwork bulging caused by using unreasonable mix proportions, side formwork support methods, and curing methods during the pouring of large-volume concrete in formal projects, thus providing guidance for subsequent construction. The formwork system and its support and fixing system of this testing system are reusable. The concrete models made using this testing system can be reused for large equipment foundations such as tower crane foundations and construction elevator foundations, saving the construction time and materials required for such equipment construction. Attached Figure Description

[0026] Figure 1 This is a cross-sectional view of the template system of the present invention;

[0027] Figure 2 This is a top view of the template system of the present invention;

[0028] Figure 3 This is a partial detail view of the template / insulation system of the present invention;

[0029] Figure 4 This is a detailed drawing of the steel pipe support of the present invention;

[0030] Figure 5 This is a detailed view of the pull screw of the present invention;

[0031] Figure 6 A cross-sectional view of the steel bar support of the present invention;

[0032] Figure 7 This is a top view of the steel bar support of the present invention;

[0033] Figure 8 This is a top view of the planar arrangement of the temperature measuring points in this invention;

[0034] Figure 9 An elevation view showing the arrangement of temperature sensors at each temperature measurement point location in this invention. Detailed Implementation

[0035] The technical solutions in the embodiments of the present invention will be clearly and completely described below. All other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of the present invention.

[0036] Example 1

[0037] like Figure 1-9As shown, a preferred embodiment of the present invention provides a large-volume concrete test system set underground. This system includes: a foundation pit 1, a formwork system, a formwork support and fixing system, a temperature measurement system, and an insulation system. The excavation cross-section of the foundation pit 1 is trapezoidal, and the pit includes a pit slope 11. The width of the trapezoidal base is the model width + 2m, providing operating space at the bottom of the pit. The slope of the pit slope 11 is determined based on soil characteristics, generally ranging from 30° to 80°. A 100mm thick C15 concrete cushion layer 12 is poured on the bottom of the foundation pit 1. The formwork system includes multiple evenly spaced vertically arranged I-beams 31, which enclose a square-section concrete pouring space. Four pieces of glued laminated timber formwork 32 are fixedly connected to the inner side of the I-beams 31, and multiple double-channel steel bars 33 are spaced vertically along the outer side of the I-beams 31. A steel reinforcement support system is installed inside the concrete pouring space. The formwork support and fixing system includes multiple formwork supports 4. One end of each formwork support 4 is fixedly connected to a double-channel steel 33, and the other end is fixedly connected to the foundation pit slope 11. The horizontal formwork supports 4 can resist the lateral pressure of concrete pouring. The temperature measurement system includes multiple temperature sensors, which are arranged at different temperature measurement points inside the concrete pouring space via sensor-attached steel bars 5. The insulation system is fixedly installed on the inside of the glued laminated timber formwork 32.

[0038] Furthermore, the steel reinforcement support system includes protective layer spacers 21 and steel reinforcement supports 22. Multiple protective layer spacers 21 are evenly spaced above the concrete foundation 12. The strength of the protective layer spacers 21 should not be less than C25. The steel reinforcement supports 22 are placed on the protective layer spacers 21.

[0039] Furthermore, the protective layer pads 21 are arranged at 1m intervals along the horizontal and vertical directions, and the steel reinforcement support 22 includes 9 vertical steel bars 221. The top of the steel reinforcement support 22 is provided with 3 horizontal reinforcing bars 222, which are welded to the vertical steel bars 221. The steel reinforcement support 22 is also provided with multiple transverse structural steel bars 223 and diagonal structural steel bars 224, which are welded to the vertical steel bars 221 respectively.

[0040] Furthermore, the formwork support 4 includes a steel pipe 41, an adjustable bottom support 42, and an adjustable top support 43. The adjustable bottom support 42 and the adjustable top support 43 are rotatably mounted on both ends of the steel pipe 41. The adjustable top support 43 is supported on the double channel steel 33, and the adjustable bottom support 41 is supported on the slope 11 of the foundation pit. The formwork support fixing system is also equipped with multiple layers of tie rods 44. The tie rods 44 are set at the four corners of the glued laminated timber formwork 32, and the four glued laminated timber formwork 32 are connected into a whole by the tie rods 44.

[0041] Furthermore, in this embodiment, four temperature measurement points are horizontally set, such as... Figure 9As shown, temperature measuring points 1, 2, 3, and 4 are located at the end, middle, and 1 / 4 of a diagonal line inside the formwork system, and at the midpoint of an edge line, respectively. This arrangement allows for accurate measurement of the internal temperature of the concrete, while the 1 / 4 diagonal point serves as a backup point for the entire temperature measuring system, preventing data loss due to component failure. Each temperature measuring point is vertically equipped with a first temperature sensor 51, a second temperature sensor 52, a third temperature sensor 53, a fourth temperature sensor 54, and a temperature receiver. The first, second, third, and fourth temperature sensors 51, 52, 53, and 54 are fixed to the sensor attachment steel bars 5 and are connected to the temperature receiver via data transmission lines. The first, second, and third temperature sensors 51, 52, and 53 are located inside the concrete, with the first sensor 51 200mm from the top surface, the second sensor 52 at the center, the third sensor 53 200mm from the bottom surface, and the fourth sensor 54 exposed to the atmosphere.

[0042] Example 2

[0043] In one specific embodiment, the plywood formwork 32 is 18mm thick, and the I-beams 31 are H20 with a height of 200mm. The plywood formwork 32 and the I-beams 31 are fixedly connected by nails, with a spacing of 300mm between adjacent I-beams 31. The double-channel steel 33 is [10-type steel] with a height of 100mm, placed horizontally, and arranged in four rows along the length of the I-beams 31. The distances of the four double-channel steel 33 from the ground are 300mm, 1300mm, 2500mm, and 2900mm, respectively. The I-beams 31 and the double-channel steel 33 are connected by channel steel beam connecting fasteners 9. The height of the I-beams 31 is 200mm, and the spacing between adjacent I-beams 31 is 300mm.

[0044] Furthermore, the insulation system uses a 5cm thick extruded polystyrene board 6, which is connected to the glued laminated timber template 32 with glue. A transparent plastic film 7 with a thickness of 1mm is placed on top of the test system, and a cotton felt 8 with a thickness of 4mm is covered on the plastic film 7.

[0045] Example 3

[0046] In this embodiment, the pit depth is 4100mm, the pit slope is 75° based on the geological conditions of this example, and the bottom of the pit is square with a side length of 6400mm. When the temperature sensor is attached to the sensor attachment steel bar, it should be kept perpendicular to the sensor attachment steel bar.

[0047] In this embodiment, the construction method of the large-volume concrete test system includes the following steps:

[0048] Step S1: Excavate the foundation pit 1 according to the location of the upper edge line 13, the lower edge line 14, and the foundation pit slope 11, and set up a temporary guardrail 15 2m away from the edge of the foundation pit. The guardrail is not less than 1.1m above the ground.

[0049] Step S2: Pour concrete foundation 12. The concrete strength is C15 and the thickness of the concrete foundation is 100mm.

[0050] Step S3: Lay out lines at 1m intervals in both the horizontal and vertical directions, and place concrete protective layer spacers 21 according to the layout positions. After the protective layer spacers 21 are placed, begin tying the bottom and top reinforcing mesh on the ground near the foundation pit. After the bottom reinforcing mesh is completed, use a crane to lift it into the bottom of the foundation pit. After the bottom reinforcing mesh is in place, begin fabricating reinforcing bar supports 22 on the ground near the foundation pit. After fabrication, lift the supports into the foundation pit, and finally place the top reinforcing mesh on the reinforcing bar supports 22.

[0051] Step S4: Process the formwork system and hoist it into the foundation pit to create a space for concrete pouring. Specifically, first, nail the I-beams 31 to the plywood formwork 32 on the ground near the foundation pit. The I-beams 31 are placed vertically. Then, use the channel steel beam connecting fasteners 9 to connect the double channel steel 33 to the I-beams 31. The double channel steel 33 is placed horizontally. After the plywood formwork 32, I-beams 31, and double channel steel 33 are connected as a whole, the extruded polystyrene board 6 is glued to the surface of the plywood formwork 32. After the four formwork pieces are processed, they are hoisted into the foundation pit using the lifting rings 34 on the I-beams 31.

[0052] Step S5: Erect the formwork support and fixing system, and connect the formwork support and fixing system to the formwork system and the foundation pit slope 11. Specifically, firstly, the four formwork panels are connected into a whole by tie rods 44. The tie rods 44 are set at the four corners of the plywood formwork 32, with a total of 4 layers, and the heights from the ground are 300mm, 1300mm, 2500mm, and 2900mm respectively. The tie rods 44 consist of one tie rod 441 and two tie seats 442. The tie seats 442 are fixed to the double channel steel 33. After the tie rods 44 are set, the formwork support 4 is erected. The overall length of the formwork support 4 is adjusted by rotating the adjustable bottom support 42 and the adjustable top support 43. The adjustable top support 43 is supported on the double channel steel 33, and the adjustable bottom support 42 is supported on the foundation pit slope 11.

[0053] Step S6: Establish the temperature measurement system. Specifically, first, determine the positions of four temperature measurement points by laying out lines. Fix the first temperature sensor 51, the second temperature sensor 52, the third temperature sensor 53, and the fourth temperature sensor 54 to the sensor attachment steel bars 5, and connect them to the temperature receiver via data transmission lines. The first temperature sensor 51 is 200mm from the top surface, the second temperature sensor 52 is located in the center, the third temperature sensor 53 is 200mm from the bottom surface, and the fourth temperature sensor 54 is placed in the atmosphere. The temperature receiver is tied to the top of the sensor attachment steel bars 5 with a rope. After fixing the temperature sensors, temperature receivers, and sensor attachment steel bars 5, place the four sensor attachment steel bars 5 at the previously determined four temperature measurement point positions.

[0054] Step S7: Pour concrete in layers.

[0055] Step S8: After the concrete is poured, cover it with plastic film 7, and then cover it with cotton felt 8 for curing.

[0056] Step S9: Perform temperature measurement. The temperature receiver is turned on before concrete pouring and automatically stores temperature data after being turned on, with a storage interval of 1 hour.

[0057] Step S10: Demolding and Backfilling. Temperature measurement ends and demolding and backfilling commences when the temperature difference between the internal concrete temperature and the surface atmospheric temperature is less than 20°C for three consecutive days. In this step, data from each temperature sensor at the four temperature measurement locations needs to be monitored. Temperature measurement ends when the temperature difference between all temperature sensors (in this embodiment, the first, second, and third temperature sensors at the four temperature measurement points) and the atmospheric temperature (the temperature data from the fourth temperature sensor) is less than 20°C for three consecutive days.

[0058] Step S11: 28 days after pouring, core samples are taken to measure the concrete strength.

[0059] In this example, three temperature sensors are installed inside the concrete at each temperature measurement point location. In other examples, this can be adjusted according to the concrete thickness.

[0060] In this example, the slope of the foundation pit slope 11 is 75°. In other examples, it should be adjusted according to the actual geological conditions.

[0061] In this example, the concrete model dimensions are 4000mm × 4000mm × 4000mm. These dimensions can be adjusted in other examples according to actual requirements. Generally, the concrete test model is a cube, and its side length is not less than the thickness of the large-volume concrete in the subsequent formal project. When the concrete side length changes, the spacing of the wooden I-beams, double-channel steel, steel pipe supports, etc., in the formwork support system should also be adjusted, and the spacing of the components in the rebar support should also be adjusted accordingly.

[0062] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A large-volume concrete test system, which is set up underground, characterized in that: The large-volume concrete test system includes: The foundation pit (1) has a trapezoidal excavation profile. The foundation pit (1) includes a foundation pit slope (11) and a concrete cushion layer (12) is poured on the bottom surface of the foundation pit (1). The template system includes multiple vertically arranged I-beams (31) at even intervals, and the I-beams (31) enclose a concrete pouring space with a square cross-section. Four pieces of glued laminated timber template (32) are fixedly connected to the inner side of the I-beams (31), and multiple double-channel steel (33) are arranged at intervals along the length direction of the outer side of the I-beams (31). A steel reinforcement support system is installed inside the concrete pouring space; The template support and fixing system includes multiple template supports (4), one end of which is fixedly connected to the double channel steel (33), and the other end is fixedly connected to the foundation pit slope (11). The horizontally set template supports (4) resist the lateral pressure of concrete pouring. The temperature measurement system includes multiple temperature sensors, which are arranged at different temperature measurement points inside the concrete pouring space via sensor-attached steel bars (5); and The thermal insulation system is fixedly installed on the inner side of the glued laminated timber formwork (32); The steel reinforcement support system includes protective layer pads (21) and steel reinforcement supports (22). Multiple protective layer pads (21) are evenly spaced above the concrete foundation (12), and the steel reinforcement supports (22) are positioned above the protective layer pads (21). The steel reinforcement supports (22) include 9 vertical steel bars (221), and 3 horizontal reinforcing bars (222) are provided at the top of the steel reinforcement supports (22). The horizontal reinforcing bars (222) are welded to the vertical steel bars (221). The steel reinforcement supports (22) also include multiple transverse structural steel bars (223) and diagonal structural steel bars (224). The transverse structural steel bars (223) and diagonal structural steel bars (224) are welded to the vertical steel bars (221) respectively. Four temperature measurement points are set up, located at the end, middle, 1 / 4 of a diagonal of the concrete pouring space and the midpoint of one of the side lines. Each temperature measurement point is equipped with a first temperature sensor (51), a second temperature sensor (52), a third temperature sensor (53), a fourth temperature sensor (54) and a temperature receiver (55) arranged vertically. The first temperature sensor (51), the second temperature sensor (52), the third temperature sensor (53) and the fourth temperature sensor (54) are fixed on the sensor attachment steel bar (5) and are respectively connected to the temperature receiver (55) through the data transmission line (56). The first temperature sensor (51) is 200mm away from the top surface, the second temperature sensor (52) is located in the center, the third temperature sensor (53) is 200mm away from the bottom surface, and the fourth temperature sensor (54) is placed in the atmosphere. The template support (4) includes a steel pipe (41), an adjustable bottom support (42), and an adjustable top support (43). The adjustable bottom support (42) and the adjustable top support (43) are rotatably mounted on both ends of the steel pipe (41). The adjustable top support (43) is supported on a double channel steel (33), and the adjustable bottom support (41) is supported on the slope (11) of the foundation pit. The template support fixing system is also provided with multiple layers of tie rods (44). The tie rods (44) are set at the four corners of the glued laminated timber template (32), and the four glued laminated timber templates (32) are connected into a whole by the tie rods (44).

2. The large-volume concrete test system according to claim 1, characterized in that: The protective layer pads (21) are arranged at 1m intervals along the horizontal and vertical directions, respectively.

3. The large-volume concrete test system according to claim 1, characterized in that: The plywood formwork (32) and the I-beams (31) are fixedly connected by nails. The double channel steel (33) is arranged in four rows along the length of the I-beams (31). The distances of the four double channel steel (33) from the ground are 300mm, 1300mm, 2500mm and 2900mm respectively. The I-beams (31) and the double channel steel (33) are connected by channel steel beam connecting fasteners (9). The height of the I-beams (31) is 200mm and the interval between two adjacent I-beams (31) is 300mm.

4. The construction method of the large-volume concrete test system according to any one of claims 1-3, characterized in that: Includes the following steps: S1. Excavation of the foundation pit (1); S2, pour concrete foundation (12); S3. Place concrete protective layer pads (21). After the protective layer pads (21) are placed, process and place the steel reinforcement brackets (22) and steel mesh. S4. Process the formwork system and hoist it into the foundation pit to create a space for concrete pouring. S5. Erect a formwork support and fixing system and connect the formwork support and fixing system to the formwork system and the foundation pit slope (11); S6. Establish a temperature measurement system; S7. Layered concrete pouring; S8. After the concrete is poured, cover it with a plastic film (7), and then cover it with cotton felt (8) for curing. S9. Take temperature measurement; S10, Demolding and backfilling; S11. 28 days after the pouring is completed, core samples are taken to measure the concrete strength; In step S4, processing the template system and hoisting the template system into the foundation pit includes: first, nailing the I-beam (31) to the plywood template (32) with nails on the ground near the foundation pit. The I-beam (31) is placed vertically. Then, the double channel steel (33) is connected to the I-beam (31) with the channel steel beam connecting fastener (9). The double channel steel (33) is placed horizontally. After the plywood template (32), the I-beam (31), and the double channel steel (33) are connected as a whole, the extruded polystyrene board (6) is glued to the surface of the plywood template (32). After the four templates are processed, they are hoisted into the foundation pit through the lifting ring (34) on the I-beam (31). In step S6, establishing the temperature measurement system includes: firstly, determining the positions of four temperature measurement points by laying out lines; fixing the first temperature sensor (51), the second temperature sensor (52), the third temperature sensor (53), and the fourth temperature sensor (54) on the sensor attachment steel bar (5) and connecting them to the temperature receiver via data transmission lines; the first temperature sensor (51) is 200mm from the top surface, the second temperature sensor (52) is located in the center, the third temperature sensor (53) is 200mm from the bottom surface, and the fourth temperature sensor (54) is placed in the atmosphere; the temperature receiver is tied to the top of the sensor attachment steel bar (5) with a rope; after fixing the temperature sensor, the temperature receiver, and the sensor attachment steel bar (5), the sensor attachment steel bar (5) is placed at the four previously determined temperature measurement point positions.

5. The construction method according to claim 4, characterized in that: In step S5, the formwork support and fixing system is erected and connected to the formwork system and the foundation pit slope (11). This includes: First, four formwork panels are connected into a whole by tie rods (44). The tie rods (44) are set at the four corners of the plywood formwork (32). A total of four layers are set, with ground heights of 300mm, 1300mm, 2500mm and 2900mm respectively. After the tie rods (44) are set, the formwork support (4) is erected. The overall length of the formwork support (4) is adjusted by rotating the adjustable bottom support (42) and the adjustable top support (43). The adjustable top support (43) is supported on the double channel steel (33), and the adjustable bottom support (42) is supported on the foundation pit slope (11).

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