Single-box multi-chamber concrete box type structure sunlight temperature field full-scale model and test method

Abstract

The invention relates to a single-box multi-chamber concrete box type structure sunlight temperature field full-scale model and a test method, the model comprises a bridge full-scale simplified model body, the bridge full-scale simplified model body is placed on a liftable support pier, and the posture of the bridge full-scale simplified model body is adjusted through the support pier; an insulation board for thermal isolation is arranged at the section of the model body; the model body shortens a transverse equal-thickness section and a vertical equal-thickness section of a bridge according to a finite element simulation result, neglects curvature during an arch bridge sunshine temperature field test when the temperature change of the arch bridge in the arch axis direction is smaller than a set value, and adopts a straight section with an inclination angle to replace a curved section. Obtaining an inclination angle required by the bridge full-scale simplified model body to simulate an arch bridge segment; a temperature sensor is embedded in the bridge full-scale simplified model body, and temperature field changes of corresponding positions in the model are collected through the temperature sensor. According to the invention, the test cost can be reduced on the basis of ensuring the accuracy of test results.

Description

Technical Field

[0001] The invention relates to the technical field of bridge temperature effect testing, and in particular to a full-scale model of a single-box multi-chamber concrete box structure sunlight temperature field and a testing method. Background Art

[0002] With the rapid development of bridge structures, concrete box girder bridges are becoming more and more widely used. However, such structures are always in a natural environment with alternating temperatures. They exchange heat with the surrounding environment through thermal radiation, thermal convection and thermal conduction. Due to the poor thermal conductivity of concrete, the temperature distribution and temperature stress of such structures are very complex. [1] .

[0003] As the engineering community pays more and more attention to the hazards of temperature stress to structures, bridge workers at home and abroad have begun to study it through various means, including real bridge monitoring, numerical simulation and experimental research.

[0004] Due to the difficulty and high cost of full-scale model tests, current experimental studies on bridge temperature fields mostly use scaled models. However, once the bridge is reduced in scale, the thickness of each part of its cross section will be reduced. If the temperature gradient is studied on this basis, the results will be inaccurate. Therefore, how to reduce the scale of the model, reduce the difficulty and cost of the test while ensuring that the key dimensions of the cross section remain unchanged is one of the problems that need to be solved. In addition, most of the existing research objects are reinforced concrete box-beam bridges. For reinforced concrete box-type arch bridges, due to the existence of the arch axis, the height of the arch rib section changes along the longitudinal direction, and the solar radiation received by the top plate and the web along the longitudinal direction is also different. However, whether the longitudinal dimension can be shortened, how to shorten it is also a problem that needs to be solved.

[0005] References

[0006] [1] Yan Gang. Analysis of temperature field and temperature effect of long-span basket-type steel truss arch bridge[D]. Sichuan: Southwest Jiaotong University, 2019. Summary of the invention

[0007] The purpose of the present invention is to provide a full-scale model of the sunlight temperature field of a single-box multi-chamber concrete box structure and a test method to address the problems in the above-mentioned prior art, thereby simplifying the model structure and reducing the test cost while ensuring the accuracy of the test results.

[0008] In order to achieve the above object, the present invention has the following technical solutions:

[0009] In the first aspect, an embodiment of the present invention provides a full-scale model of the sunlight temperature field of a single-box multi-chamber concrete box structure, including a full-scale simplified model body of a bridge, wherein the full-scale simplified model body of the bridge is placed on a supporting pier that can be raised and lowered, and the posture of the full-scale simplified model body of the bridge is adjusted by the supporting pier; an insulation board for thermal isolation is provided at the cross section of the full-scale simplified model body of the bridge; the full-scale simplified model body of the bridge shortens the transverse equal-thickness section and the vertical equal-thickness section of the bridge according to the finite element simulation results, and according to the temperature change along the arch axis direction of the arch bridge, when it is less than a set value, the curvature is ignored when conducting the sunlight temperature field test of the arch bridge, and a straight section with an inclination angle is used instead of a curved section to obtain the inclination angle required for the full-scale simplified model body of the bridge to simulate the arch bridge segment; a temperature sensor is buried inside the full-scale simplified model body of the bridge, and the temperature field changes at the corresponding positions inside the model are collected by the temperature sensor.

[0010] As a preferred solution, the supporting pier includes a base, a hydraulic jack and a load-bearing support which are connected in sequence.

[0011] As a preferred solution, the load-bearing support and the full-scale simplified model body of the bridge are connected by plywood that can be thermally isolated.

[0012] As a preferred solution, when simulating box beam bridges and arch bridges, the full-scale simplified model body of the bridge selects the most unfavorable section under the action of the temperature field or other sections with special requirements for testing according to the bridge site and bridge direction.

[0013] As a preferred solution, the full-scale simplified model body of the bridge is shortened to 2 / 5 of the actual bridge transverse equal-thickness section based on finite element simulation results.

[0014] As a preferred solution, the full-scale simplified model body of the bridge is shortened to 2 / 5 of the vertical equal-thickness section of the actual bridge based on the finite element simulation results.

[0015] As a preferred solution, according to the finite element simulation results, when the temperature variation of the arch bridge along the arch axis is less than 1%, the curvature is ignored during the arch bridge sunlight temperature field test, and a straight section with an inclined angle is used instead of a curved section.

[0016] As a preferred solution, the insulation board is covered with a shading cloth and holes are opened on the insulation board. The insulation board can meet the thermal isolation requirements of the full-scale simplified model of the bridge along the span direction of the bridge, prevent light from entering the box cavity and realize the exchange between the box and the outside atmosphere.

[0017] In a second aspect, an embodiment of the present invention further proposes a test method based on the full-scale model of the single-box multi-chamber concrete box structure sunlight temperature field, comprising the following steps:

[0018] For different types of box bridge structures, set up a simplified full-scale model of the bridge:

[0019] When the actual bridge in the sunshine temperature field test is a box-beam bridge, and the model is required to be placed longitudinally and horizontally according to the actual working conditions in the experiment, each supporting pier is activated synchronously, and the lifting and lowering stroke of each supporting pier is adjusted to ensure that the model can be set in the same posture as the actual bridge, that is, the longitudinal posture of the model is consistent with the horizontal state of the actual bridge;

[0020] When the actual bridge in the sunshine temperature field test is a box-type arch bridge, firstly, determine the specific structural segment of the arch bridge to be simulated, and calculate the curvature information of the corresponding segment based on the structural parameters of the actual arch bridge. When the temperature change along the arch axis of the arch bridge is less than the set value, ignore the curvature and use a straight segment with an inclination angle to replace the curved segment, and obtain the inclination angle required for the full-scale simplified model of the bridge to simulate the arch bridge segment. Then, by adjusting the lifting stroke of each supporting pier, the inclination angle of each segment of the model under the simulated experimental state can reproduce the inclination condition of the corresponding segment of the actual arch bridge.

[0021] The temperature field test is carried out on the set full-scale simplified model of the bridge. The temperature sensors buried inside the full-scale simplified model of the bridge are used for real-time monitoring to obtain the temperature field changes at the corresponding positions inside the model.

[0022] As a preferred solution, if a daily temperature field study is conducted, the sampling frequency is 5 minutes per time; if an annual temperature field study is conducted, the sampling frequency is 10 minutes per time; after collecting the temperatures at different positions and times of the box-type bridge structure using the full-scale simplified model of the bridge, the data is screened to exclude erroneous data, and the screened data is analyzed to obtain the temperature variation law.

[0023] Compared with the prior art, the present invention has at least the following beneficial effects:

[0024] Due to its huge volume, the temperature distribution inside the concrete box structure after pouring shows a significant non-uniform characteristic. Among them, the middle area of ​​the web shows a relatively low temperature change rate due to its large thickness and the thermal conductivity of the material. The response to the change of the external ambient temperature is mainly reflected in the top and bottom plates with large surface areas. Considering that the top and bottom plates can be regarded as flat plate elements with a large enough area for effective heat exchange, under a reasonable heat conduction model, even if the horizontal and vertical dimensions of the top and bottom plates are moderately reduced, as long as sufficient heat transfer area is maintained to ensure effective heat dissipation, this change will not substantially affect the temperature gradient distribution inside the box girder in the vertical direction. Similarly, following the above principle, the lateral temperature gradient of the web can also be maintained in equilibrium through similar thermodynamic analysis. The full-scale simplified model body of the bridge of the present invention shortens the transverse equal-thickness section and the vertical equal-thickness section of the bridge according to the finite element simulation results, and according to the temperature change along the arch axis direction of the arch bridge, when it is less than a set value, the curvature is ignored when performing the arch bridge sunshine temperature field test, and a straight section with an inclination angle is used instead of a curved section to obtain the inclination angle required for the full-scale simplified model body of the bridge to simulate the arch bridge segment. This can not only solve the problems of inaccurate results of the scaled model and insufficient research on the arch bridge temperature field model test, but also greatly reduce the cost of the full-scale model. It is applicable to both ordinary box beam bridges and box arch bridges. The model proposed by the present invention can ensure that the temperature gradient at the location with larger temperature stress remains unchanged on the basis of reducing costs, and the test results are accurate, easy to operate, and has a wide range of applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The drawings constituting a part of this application are used to provide a further understanding of the technical solution of this application. The illustrative embodiments of this application and their descriptions are only used to explain this application and do not constitute an improper limitation on the protection scope of this application.

[0026] Figure 1 It is a schematic diagram of the full-scale model structure of the sunlight temperature field of a single-box multi-chamber concrete box structure according to an embodiment of the present invention;

[0027] Figure 2 It is an overall structural explosion diagram of a full-scale model of the sunlight temperature field of a single-box multi-chamber concrete box structure according to an embodiment of the present invention;

[0028] Figure 3 This is a schematic diagram of the supporting pier structure according to an embodiment of the present invention;

[0029] Figure 4 It is a schematic cross-sectional view of a box girder bridge model body according to an embodiment of the present invention;

[0030] Figure 5 This is a layout diagram of a temperature sensor embedded in a box beam bridge model body according to an embodiment of the present invention;

[0031] Figure 6This is a cloud diagram of the longitudinal temperature distribution of the arch bridge in Example 18 of the present invention (taking half the span L / 2);

[0032] Figure 7 This is a longitudinal temperature distribution curve diagram of a certain point in the cross section of an arch bridge in Example 18 of the present invention (taking half the span L / 2);

[0033] Figure 8 The temperature distribution cloud diagram of the transverse equal thickness section of the box girder according to the embodiment of the present invention is as follows:

[0034] (a) No shortening; (b) Shortened by 0.75 m; (c) Shortened by 1.5 m; (d) Shortened by 2.25 m; (e) Shortened by 3 m;

[0035] Fig. 9 The vertical temperature gradient cloud diagram of the transverse equal thickness section of the box girder according to the embodiment of the present invention is as follows:

[0036] (a) No shortening; (b) Shortened by 0.75 m; (c) Shortened by 1.5 m; (d) Shortened by 2.25 m; (e) Shortened by 3 m;

[0037] Fig.10 This is a cloud diagram of the transverse temperature gradient of the box girder transverse equal thickness section according to an embodiment of the present invention:

[0038] (a) No shortening; (b) Shortened by 0.75 m; (c) Shortened by 1.5 m; (d) Shortened by 2.25 m; (e) Shortened by 3 m;

[0039] Fig.11 This is a comparison diagram of the temperature distribution of the top plate of the box beam after transverse shortening in an embodiment of the present invention;

[0040] Fig.12 This is a comparison diagram of the temperature distribution of the bottom plate of the box beam after transverse shortening in an embodiment of the present invention;

[0041] Fig.13 This is a comparison diagram of the temperature distribution of the web on the sunward side after being shortened laterally according to an embodiment of the present invention;

[0042] Fig.14 This is a comparison diagram of the temperature distribution of the middle web after transverse shortening of an embodiment of the present invention;

[0043] Fig.15 The temperature distribution cloud diagram of the vertical equal thickness section of the box girder according to the embodiment of the present invention is as follows:

[0044] (a) No shortening; (b) Shortening by 0.5 m; (c) Shortening by 1 m; (d) Shortening by 1.5 m; (e) Shortening by 2 m;

[0045] Fig.16 The vertical temperature gradient cloud diagram of the vertical equal thickness section of the box girder according to the embodiment of the present invention is as follows:

[0046] (a) No shortening; (b) Shortening by 0.5 m; (c) Shortening by 1 m; (d) Shortening by 1.5 m; (e) Shortening by 2 m;

[0047] Fig.17 This is a cloud diagram of the transverse temperature gradient of the vertical equal thickness section of the box girder according to the embodiment of the present invention:

[0048] (a) No shortening; (b) Shortening by 0.5 m; (c) Shortening by 1 m; (d) Shortening by 1.5 m; (e) Shortening by 2 m;

[0049] Fig.18 This is a comparison diagram of the temperature distribution of the top plate of the box beam after vertical shortening according to an embodiment of the present invention;

[0050] Fig.19 This is a comparison diagram of the temperature distribution of the bottom plate of the box beam after vertical shortening according to an embodiment of the present invention;

[0051] Fig. 20 This is a comparison diagram of the temperature distribution of the web on the sunward side after vertical shortening in an embodiment of the present invention;

[0052] Fig.21 This is a comparison diagram of the temperature distribution of the middle web after vertical shortening of an embodiment of the present invention;

[0053] In the attached figure: 1- full-scale simplified model of the bridge; 2- supporting pier; 201- base; 202- hydraulic jack; 203- load-bearing support; 3- insulation board; 4- plywood. DETAILED DESCRIPTION

[0054] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0055] It should be noted that, in the description of the embodiments of the present invention, unless otherwise specified, “multiple” means two or more; the orientations or positional relationships indicated by terms such as “upper”, “lower”, “left”, “right”, “inside”, “outside”, “front end”, “rear end”, “head” and “tail” are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0056] Meanwhile, in the description of the present invention, unless otherwise clearly specified and limited, the terms "connected" and "connection" 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. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0057] Due to its huge volume, the temperature distribution inside the concrete box structure after pouring shows a significant non-uniform characteristic. Among them, the middle area of ​​the web shows a relatively low temperature change rate due to its large thickness and the thermal conductivity of the material. The response to the change of the external ambient temperature is mainly reflected in the top and bottom plates with large surface areas. Considering that the top and bottom plates can be regarded as flat plate elements with a large enough area for effective heat exchange, under a reasonable heat conduction model, even if the horizontal and vertical dimensions of the top and bottom plates are moderately reduced, as long as sufficient heat transfer area is maintained to ensure effective heat dissipation, this change will not substantially affect the temperature gradient distribution inside the box girder in the vertical direction. Similarly, following the above principle, the lateral temperature gradient of the web can also be maintained in equilibrium through similar thermodynamic analysis.

[0058] However, it should be pointed out that the top plate, bottom plate and web plate are an integral box girder system that works together, and the heat transfer and temperature distribution between them are coupled with each other. The adjustment of the size of any single component must fully consider its impact on the temperature field and the accompanying thermal stress in the entire box girder structure. Therefore, in practical applications, although the size of each part can be reasonably optimized to reduce the test cost, it must be ensured that the size adjustment will not excessively weaken the overall thermal stability and durability of the structure, avoid inducing unacceptable risks of temperature cracks or other structural damage caused by temperature stress, and affect the accuracy of the test results.

[0059] Therefore, the embodiment of the present invention uses ANSYS software to perform finite element simulation of the temperature field of a single-box double-chamber arch bridge. Since the highest temperature and the maximum vertical temperature difference of the single-box multi-chamber box beam appear at the axil position, in addition to analyzing its longitudinal temperature distribution, the lengths of its transverse top and bottom plate and vertical web plate and other thick sections (key dimensions, key positions) are reduced respectively, and the temperature distribution of the top, bottom plate and web plate near the axil is analyzed; and based on the calculation results, a full-scale model and test method of the sunlight temperature field of a single-box multi-chamber concrete box structure are proposed. The present invention can greatly reduce the cost of the full-scale model, which can be applied not only to ordinary box beam bridges, but also to box arch bridges, and has important economic value and application prospects.

[0060] See also Figure 1 and Figure 2The full-scale model of the sunlight temperature field of a single-box multi-chamber concrete box structure of an embodiment of the present invention includes a full-scale simplified model body 1 of a bridge. The full-scale simplified model body 1 of the bridge is placed on a support pier 2 that can be raised and lowered. The posture of the full-scale simplified model body 1 of the bridge can be adjusted by the support pier 2, such as Figure 3 As shown, the supporting pier 2 of the embodiment of the present invention comprises a base 201, a hydraulic jack 202 and a load-bearing support 203 which are connected in sequence. The load-bearing support 203 is connected to the full-scale simplified model body 1 of the bridge through two layers of plywood 4 capable of thermal isolation. Insulation boards 3 for thermal isolation are arranged at the cross sections on both sides of the full-scale simplified model body 1 of the bridge. The insulation boards 3 are attached with shading cloth and holes are opened on the insulation boards 3. The insulation boards 3 can meet the thermal isolation of the full-scale simplified model body 1 of the bridge along the span direction of the bridge, prevent light from entering the box cavity and realize the exchange between the box and the outside atmosphere. The full-scale simplified model body 1 of the bridge shortens the transverse equal-thickness section and the vertical equal-thickness section of the bridge according to the finite element simulation results, and according to the temperature change along the arch axis direction of the arch bridge, when it is less than the set value, the curvature is ignored when conducting the arch bridge sunshine temperature field test, and the straight section with an inclination angle is used instead of the curved section to obtain the inclination angle required for the full-scale simplified model body 1 of the bridge to simulate the arch bridge segment; the temperature sensor is buried inside the full-scale simplified model body 1 of the bridge, and the temperature field change at the corresponding position inside the model is collected by the temperature sensor. Since the full-scale simplified model body 1 of the bridge of the present invention is placed on the supporting pier 2, the model is prevented from contacting with the ground for heat exchange, and the actual load of the ground reflected radiation can be simulated at the same time. In addition, the space provided by the supporting pier 2 allows air to flow freely to the lower surface of the bottom plate of the model body, which can simulate the actual convection load.

[0061] The hydraulic jack 202 of the embodiment of the present invention can accurately adjust the height of the supporting pier 2, thereby adjusting the angle of the full-scale simplified model body 1 of the bridge, and completing the sunshine temperature field test of different sections of the arch bridge.

[0062] The test of the embodiment of the present invention selects a site whose distance to the nearest building is less than its shielding length and is as close to the actual bridge position as possible to better simulate the real thermal load of the bridge and avoid the influence of the shielding of surrounding buildings on the constructed box girder.

[0063] When simulating a box beam bridge and an arch bridge, the full-scale simplified model body 1 of the bridge in the embodiment of the present invention selects the most unfavorable section under the action of the temperature field or other sections with special requirements for testing according to the bridge site and the direction of the bridge.

[0064] In a possible implementation, the full-scale simplified model body 1 of the bridge shortens the transverse equal-thickness section of the actual bridge to 2 / 5 according to the finite element simulation results, and shortens the vertical equal-thickness section of the actual bridge to 2 / 5 according to the finite element simulation results.

[0065] The full-scale simplified model of the bridge 1 is based on the finite element simulation results. When the temperature variation of the arch bridge along the arch axis is less than 1%, the curvature is ignored during the arch bridge sunshine temperature field test, and a straight section with an inclined angle is used instead of a curved section.

[0066] See also Figures 4 to 21 According to the finite element simulation results, when the transverse equal-thickness section of the bridge is shortened by 2.25m or less, the temperature change at each location of the box girder is less than 2‰, while when it is shortened by 3m, the temperature of the top and bottom plates changes significantly. Therefore, the length of the transverse equal-thickness section of the model of the present invention is set to 2 / 5 of the original length, which can reduce the model production cost as much as possible while ensuring that the temperature effect remains unchanged.

[0067] On the other hand, according to the results of finite element simulation, when the vertical equal-thickness section of the bridge is shortened by 1.5m or less, the maximum temperature change at each location of the box girder is 3.5‰, and when it is shortened by 2m, the web temperature changes significantly. Therefore, the length of the vertical equal-thickness section of the model of the present invention is set to 2 / 5 of the original, which can reduce the model production cost as much as possible while ensuring that the temperature effect remains unchanged.

[0068] Before the test, the length of the horizontal and vertical equal thickness sections was shortened based on the actual bridge drawings to make a test model. Figure 5 The sensors are buried at the temperature sensor positions shown, following the principle of "comprehensive layout, dense axils, and local adjustment", so that there are measurement points on the surface, center, and bottom of each structure. The measurement points are densely arranged at the axils and the positions of the measurement points are flexibly adjusted according to the positions of the actual bridge reinforcements. In addition, strain sensors and other types of sensors can be arranged according to research needs.

[0069] Another embodiment of the present invention further provides a test method based on the full-scale model of the single-box multi-chamber concrete box structure sunlight temperature field, comprising the following steps:

[0070] For different types of box bridge structures, set up a full-scale simplified model of the bridge 1:

[0071] When the actual bridge in the sunshine temperature field test is a box-beam bridge, and the model is required to be placed longitudinally and horizontally according to the actual working conditions in the experiment, each supporting pier 2 is activated synchronously, and the lifting stroke of each supporting pier 2 is adjusted to ensure that the model can be set in the same posture as the actual bridge, that is, the longitudinal posture of the model is consistent with the horizontal state of the actual bridge;

[0072] When the actual bridge of the sunshine temperature field test is a box-type arch bridge, firstly, the specific structural segment of the arch bridge to be simulated is determined, and the curvature information of the corresponding segment is calculated according to the structural parameters of the actual arch bridge. When the temperature change of the arch bridge along the arch axis is less than the set value, the curvature is ignored and the straight segment with an inclination angle is used instead of the curved segment to obtain the inclination angle required for the full-scale simplified model body 1 of the bridge to simulate the arch bridge segment; then, by adjusting the lifting stroke of each supporting pier 2, the inclination angle of each segment of the model under the simulated experimental state can reproduce the inclination condition of the corresponding segment of the actual arch bridge;

[0073] The temperature field test is carried out through the set full-scale simplified model body 1 of the bridge, and the temperature sensor buried inside the full-scale simplified model body 1 of the bridge is used for real-time monitoring to obtain the temperature field changes at the corresponding positions inside the model.

[0074] In a possible implementation, after the above preparation work is completed, a temperature field test can be carried out on the model segment, and a real-time monitoring scheme can be adopted. If a daily temperature field study is conducted, the sampling frequency is 5 minutes / time; if an annual temperature field study is conducted, the sampling frequency is 10 minutes / time; after the test, the model of the embodiment of the present invention is unloaded and the support pier 2 is recovered.

[0075] After collecting the temperatures at different positions and times of the box-type bridge structure using the full-scale simplified model body 1 of the bridge, the data is screened to exclude erroneous data, and the screened data is analyzed to obtain laws such as vertical temperature gradients.

[0076] The embodiment of the present invention further reduces the test cost on the basis of the full-scale model by shortening the length of thick sections such as the top plate and web of the box girder. The model proposed in the embodiment of the present invention ensures that the temperature gradient at locations with large temperature stress remains unchanged on the basis of reducing costs, and the results are accurate, easy to operate, and have a wide range of applications. The embodiment of the present invention solves the problems of difficulty and high cost of full-scale model testing, inaccurate results of scaled models, and insufficient research on temperature field model tests for arch bridges.

[0077] It is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-restrictive, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present invention, and any reference numerals in the claims should not be regarded as limiting the scope of protection involved.

[0078] The above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A full-scale model of the sunlight temperature field of a single-box multi-chamber concrete box structure, characterized in that: The invention comprises a full-scale simplified model body (1) of a bridge, wherein the full-scale simplified model body (1) of the bridge is placed on a support pier (2) that can be raised or lowered, and the posture of the full-scale simplified model body (1) of the bridge is adjusted by the support pier (2); An insulation board (3) for heat isolation is provided at the cross section of the full-scale simplified model body (1) of the bridge; the full-scale simplified model body (1) of the bridge shortens the transverse equal-thickness section and the vertical equal-thickness section of the bridge according to the finite element simulation results, and according to the temperature change along the arch axis direction of the arch bridge, when it is less than a set value, the curvature is ignored when performing the arch bridge sunshine temperature field test, and a straight section with an inclination angle is used to replace the curved section, so as to obtain the inclination angle required for the full-scale simplified model body (1) to simulate the arch bridge segment; a temperature sensor is embedded inside the full-scale simplified model body (1) of the bridge, and the temperature field change at the corresponding position inside the model is collected by the temperature sensor.

2. According to the full-scale model of the single-box multi-chamber concrete box structure sunlight temperature field according to claim 1, it is characterized in that: The supporting pier (2) comprises a base (201), a hydraulic jack (202) and a load-bearing support (203) which are connected in sequence.

3. According to claim 2, the full-scale model of the sunlight temperature field of the single-box multi-chamber concrete box structure is characterized in that: The load-bearing support (203) is connected to the full-scale simplified model body (1) of the bridge via a plywood (4) capable of thermal insulation.

4. According to claim 1, the full-scale model of sunlight temperature field of single-box multi-chamber concrete box structure is characterized in that: When simulating a box-beam bridge and an arch bridge, the full-scale simplified bridge model body (1) selects the most unfavorable section under the action of the temperature field or other sections with special requirements for testing according to the bridge site and the bridge direction.

5. According to claim 1, the full-scale model of sunlight temperature field of single-box multi-chamber concrete box structure is characterized in that: The full-scale simplified bridge model body (1) is shortened to 2 / 5 of the actual bridge transverse equal-thickness section according to finite element simulation results.

6. The full-scale model of sunlight temperature field of single-box multi-chamber concrete box structure according to claim 1 is characterized in that: The full-scale simplified model body (1) of the bridge is shortened to 2 / 5 of the vertical equal-thickness section of the actual bridge according to the finite element simulation results.

7. The full-scale model of sunlight temperature field of single-box multi-chamber concrete box structure according to claim 1 is characterized in that: According to the finite element simulation results, when the temperature variation of the arch bridge along the arch axis is less than 1%, the curvature is ignored during the arch bridge sunshine temperature field test, and a straight section with an inclined angle is used instead of a curved section.

8. The full-scale model of sunlight temperature field of single-box multi-chamber concrete box structure according to claim 1 is characterized in that: The insulation board (3) is covered with a shading cloth and has holes in it. The insulation board (3) can meet the requirements of thermal isolation of the full-scale simplified bridge model body (1) along the span direction of the bridge, prevent light from entering the box cavity, and realize the exchange of the box with the outside atmosphere.

9. A test method based on the full-scale model of the single-box multi-chamber concrete box structure sunlight temperature field according to any one of claims 1 to 8, characterized in that: The following steps are involved: For different types of box bridge structures, set up a full-scale simplified model of the bridge (1): When the actual bridge in the sunshine temperature field test is a box-beam bridge, and the model is required to be placed longitudinally and horizontally according to the actual working conditions in the experiment, each supporting pier (2) is activated synchronously, and the lifting stroke of each supporting pier (2) is adjusted to ensure that the model can be set in the same posture as the actual bridge, that is, the longitudinal posture of the model is consistent with the horizontal state of the actual bridge; When the actual bridge of the sunshine temperature field test is a box-type arch bridge, firstly, the specific structural segment of the arch bridge to be simulated is determined, and the curvature information of the corresponding segment is calculated based on the structural parameters of the actual arch bridge. When the temperature change along the arch axis of the arch bridge is less than the set value, the curvature is ignored and a straight segment with an inclination angle is used instead of the curved segment to obtain the inclination angle required for simulating the arch bridge segment of the full-scale simplified model body (1) of the bridge; then, by adjusting the lifting stroke of each supporting pier (2), the inclination angle of each segment of the model under the simulated experimental state can reproduce the inclination condition of the corresponding segment of the actual arch bridge; A temperature field test is carried out by using a set full-scale simplified model body (1) of the bridge, and real-time monitoring is carried out using a temperature sensor embedded inside the full-scale simplified model body (1) of the bridge to obtain temperature field changes at corresponding positions inside the model.

10. The test method according to claim 9, characterized in that: If the daily temperature field study is conducted, the sampling frequency is 5 minutes per time; if the annual temperature field study is conducted, the sampling frequency is 10 minutes per time; After collecting the temperatures at different positions and times of the box-type bridge structure using the full-scale simplified model of the bridge (1), the data are screened to exclude erroneous data, and the screened data are analyzed to obtain the temperature variation law.

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