Multi-span continuous bridge temperature deformation regulation and control system and design method

Abstract

The invention discloses a multi-span continuous bridge temperature deformation regulation and control system and a design method, and belongs to the technical field of bridge operation and maintenance. The multi-span continuous bridge temperature deformation regulation and control system comprises a main beam, a plurality of bridge piers and a longitudinal displacement adjustment assembly. Each pier is provided with two supports which are arranged at an interval, and the main beam is arranged on the multiple supports; each longitudinal displacement adjusting assembly comprises an upper connecting plate, a lower connecting plate, a force transmission shaft, two guide shaft sleeves, two threaded shaft sleeves and an elastic piece, the top face of each upper connecting plate is fixed to the bottom face of the corresponding main beam, two bosses are arranged on the bottom face of each upper connecting plate, and the bottom face of each lower connecting plate is fixed to the corresponding bridge pier and located between the two corresponding supports. According to the multi-span continuous bridge temperature deformation regulation and control system provided by the embodiment of the invention, temperature deformation regulation and control can be carried out on the built bridge which is open to traffic by arranging the longitudinal displacement regulation assembly, so that the system adapts to deformation of the beam end telescopic device, and the structure of the built bridge does not need to be changed.

Description

Technical Field

[0001] The present invention belongs to the technical field of bridge operation and maintenance, and in particular relates to a temperature deformation control system and a design method for a multi-span continuous bridge. Background Art

[0002] Long-span concrete continuous beams offer advantages such as high stiffness, excellent cost-effectiveness, and durability. They are widely used in railway bridge construction spanning wide and deep waters and canyons. These beams often utilize a single fixed pier for continuous restraint. Temperature fluctuations can cause significant longitudinal expansion and contraction at the beam ends, requiring full consideration of the magnitude and characteristics of these deformations in the design of the track structure at the beam ends.

[0003] There is an urgent need to upgrade the quality of previously built long-span bridges. However, the thermal deformation of the beam ends of these bridges is significant, which in turn affects the smoothness of the lines and driving comfort on the bridges. This thermal deformation needs to be controlled to accommodate the deformation of the beam end expansion and contraction devices. Currently, there is no engineering practice for controlling thermal deformation of bridges already in operation. Summary of the Invention

[0004] In response to the above-mentioned defects or improvement needs of the prior art, the present invention provides a temperature deformation control system and design method for multi-span continuous bridges. Its purpose is to control the temperature deformation of existing bridges by setting a longitudinal displacement adjustment component, thereby adapting to the deformation of the beam end expansion device without changing the structure of the existing bridge.

[0005] To achieve the above objectives, in a first aspect, the present invention provides a temperature deformation control system for a multi-span continuous bridge, the temperature deformation control system for a multi-span continuous bridge comprising a main beam, a plurality of bridge piers, and at least one longitudinal displacement adjustment assembly;

[0006] Each of the bridge piers is provided with two supports arranged at intervals, and the main beam is arranged on a plurality of the supports;

[0007] Each of the longitudinal displacement adjustment components includes an upper connecting plate, a lower connecting plate, a force transmission shaft, two guide bushings, two threaded bushings and an elastic member. The top surface of the upper connecting plate is fixed to the bottom surface of the main beam. The bottom surface of the upper connecting plate has two bosses arranged at intervals. The two bosses are slidably sleeved on the two ends of the force transmission shaft along the axial direction of the force transmission shaft. The bottom surface of the lower connecting plate is fixed to the bridge pier and is located between the two supports. The top surface of the lower connecting plate has two stoppers arranged at intervals. The two ends of the force transmission shaft are respectively inserted into the corresponding stoppers. Each The stop block is arranged at intervals with the corresponding boss to limit the position after the boss slides. The two guide sleeves, the two threaded sleeves and the elastic member are all located between the two bosses. The elastic member is sleeved on the force transmission shaft and clamped between the two threaded sleeves. The two threaded sleeves are both sleeved on the force transmission shaft. Each guide sleeve can be slidably sleeved on the corresponding threaded sleeve. One end of each guide sleeve is against the corresponding boss, and the other end of each guide sleeve is against the elastic member to drive the elastic member to compress.

[0008] Optionally, an inner flange is provided on the inner circumferential wall of one end of each guide sleeve, each inner flange is located between the corresponding boss and the corresponding threaded sleeve, and each inner flange is slidably fitted with the force transmission shaft.

[0009] Optionally, an adjusting bolt may be movably inserted into each of the stoppers, each of the adjusting bolts is coaxially arranged with the force transmission shaft, and one end of each of the adjusting bolts is against the force transmission shaft.

[0010] Optionally, each of the longitudinal displacement adjustment assemblies further includes two force transmission sleeves, each of which is slidably mounted on the force transmission shaft, the force transmission sleeve being located between the corresponding threaded sleeve and the elastic member, and the other end of each guide sleeve being against the corresponding force transmission sleeve.

[0011] Optionally, an adjustment plate is provided on one side of each stopper facing the boss, and each adjustment plate is detachably sleeved on the force transmission shaft.

[0012] Optionally, the elastic member is a plurality of disc springs.

[0013] In a second aspect, the present invention provides a method for designing a temperature deformation control system for a multi-span continuous bridge. The method is based on the temperature deformation control system for a multi-span continuous bridge according to the first aspect, and the method includes:

[0014] Determining a temperature deformation adjustment target of the main beam, wherein the temperature deformation adjustment target includes a corresponding position of the main beam and a temperature deformation range of the main beam;

[0015] Calculating the position of the target temperature deformation zero point of the main beam, and calculating the design displacement and load-bearing capacity of the longitudinal displacement adjustment assembly, wherein the design displacement is the gap between the corresponding boss and the stopper;

[0016] Based on the designed displacement, load-bearing capacity and corresponding installation space of the longitudinal displacement adjustment assembly, corresponding longitudinal displacement adjustment assemblies are provided on the piers adjacent to the target temperature deformation zero point of the main beam.

[0017] Optionally, the position of the target temperature deformation zero point of the main beam is calculated using the following formula:

[0018] ΔL=α*Δt*L;

[0019] Wherein, ΔL is the expansion and contraction of the main beam, α is the expansion and contraction coefficient of the main beam, Δt is the temperature change, and L is the distance between the position of the target temperature deformation zero point of the main beam and the corresponding position of the main beam.

[0020] Optionally, the carrying capacity is calculated in the following manner:

[0021] f0+f1+…+f i +k*x i =f i+1 +k*x i+1 +f i+2 +…+f n +T;

[0022] n is the total number of the piers, the longitudinal displacement adjustment assembly is provided on the i-th pier and the i+1-th pier, the target temperature deformation zero point of the main beam is located between the i-th pier and the i+1-th pier, f0, f1, ..., f i ,…,f n is the friction force between each support and the main beam, and the friction force between each support and the main beam is equal, k is the elastic coefficient of the elastic member, T is the bearing capacity of the longitudinal displacement adjustment assembly on the i+1th pier, x i is the deformation of the elastic member of the longitudinal displacement adjustment assembly on the i-th pier, x i+1 is the deformation of the elastic member of the longitudinal displacement adjustment assembly on the i+1th pier.

[0023] Optionally, the elastic coefficient of the elastic member is 1000-1500 kN / cm.

[0024] In general, the above technical solutions conceived by the present invention have the following beneficial effects compared with the prior art:

[0025] In a multi-span continuous bridge temperature deformation control system provided by an embodiment of the present invention, the longitudinal displacement adjustment assembly is disposed on the corresponding bridge pier. Because the elastic member is mounted on the force transmission shaft and sandwiched between two threaded sleeves, the threaded sleeves limit the ends of the elastic member, while the corresponding guide sleeves can compress the elastic member to the left or right. Furthermore, the top surface of the upper connecting plate is fixed to the bottom surface of the main beam, and the bottom surface of the upper connecting plate has two spaced-apart bosses that are slidably mounted on the ends of the force transmission shaft along the axial direction of the force transmission shaft. When the bridge pier corresponding to the main beam is deformed by expansion or contraction, the bosses move along the force transmission shaft, squeezing the elastic member through the guide sleeves, compressing the elastic member. The restoring force generated by the elastic member can regulate the deformation of the main beam. When the deformation is too large, the boss moves to counteract the block, achieving hard limiting of the upper connecting plate, so that the deformation of the main beam can also be regulated through the block.

[0026] When the temperature rises, the corresponding longitudinal displacement adjustment assembly on the main beam expands away from the center of the main beam. This means that the main beam drives the upper connecting plate and boss to the right. As the left boss moves rightward, it squeezes the elastic member, which exerts a leftward force on the boss and upper connecting plate, regulating the main beam's rightward expansion and deformation. When the temperature rises too high, the main beam drives the upper connecting plate and boss to the right until they come into contact with the right stop, achieving a hard limit. This also regulates the deformation of the main beam, and thus the temperature deformation of the beam end.

[0027] Similarly, when the temperature drops, the position of the corresponding longitudinal displacement adjustment component on the main beam shrinks toward the center of the main beam. This means that the main beam drives the upper connecting plate and boss to the left. As the right boss moves leftward, it squeezes the elastic member, which exerts a rightward force on the boss and upper connecting plate, regulating the main beam's leftward contraction and deformation. When the temperature drops too much, the main beam drives the upper connecting plate and boss to the left until they contact the left stop, achieving a hard limit. This also regulates the deformation of the main beam, and thus the temperature deformation of the beam end.

[0028] That is to say, the embodiment of the present invention provides a temperature deformation control system for a multi-span continuous bridge. By setting a longitudinal displacement adjustment component, the temperature deformation of an already built and open bridge can be controlled, thereby adapting to the deformation of the beam end expansion device without changing the structure of the already built bridge. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a transverse cross-sectional view of a temperature deformation control system for a multi-span continuous bridge provided by an embodiment of the present invention;

[0030] Figure 2 is a structural schematic diagram of a longitudinal displacement adjustment assembly provided by an embodiment of the present invention;

[0031] Figure 3 is a longitudinal cross-sectional view of a longitudinal displacement adjustment assembly provided by an embodiment of the present invention;

[0032] Figure 4 This is a flow chart of a design method for a temperature deformation control system for a multi-span continuous bridge provided by an embodiment of the present invention;

[0033] Figure 5 This is a schematic structural diagram of a railway bridge provided by an embodiment of the present invention;

[0034] Figure 6 2. It is a schematic diagram showing the change of the deformation zero point corresponding to the bridge under the temperature rising working condition provided by the embodiment of the present invention;

[0035] Figure 7 This is a schematic diagram of the change of the deformation zero point corresponding to the bridge under the cooling condition provided by an embodiment of the present invention.

[0036] In all the drawings, the same reference numerals represent the same technical features, specifically:

[0037] 1. Main beam; 2. Pier; 3. Longitudinal displacement adjustment assembly; 31. Upper connecting plate; 311. Boss; 32. Lower connecting plate; 321. Stopper; 33. Force transmission shaft; 34. Guide bushing; 341. Inner flange; 35. Threaded bushing; 36. Elastic part; 37. Adjusting bolt; 38. Force transmission sleeve; 39. Adjusting plate; 4. Support. DETAILED DESCRIPTION

[0038] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only intended to illustrate the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

[0039] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like to indicate orientations or positional relationships 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, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0040] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0041] In the present invention, unless otherwise specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection; direct connection, or indirect connection through an intermediate medium; internal communication between two components, or interaction between two components, unless otherwise specified. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0042] In the present invention, unless otherwise expressly specified or limited, when a first feature is "above" or "below" a second feature, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediary. Furthermore, when a first feature is "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0043] Example:

[0044] Figure 1 FIG. 1 is a transverse cross-sectional view of a temperature deformation control system for a multi-span continuous bridge provided by an embodiment of the present invention. Figure 1 As shown, the temperature deformation control system of a multi-span continuous bridge includes a main beam 1, multiple piers 2 and at least one longitudinal displacement adjustment component 3.

[0045] Each pier 2 is provided with two supports 4 arranged at intervals, and the main beam 1 is set on multiple supports 4.

[0046] Figure 2 is a schematic structural diagram of a longitudinal displacement adjustment assembly provided by an embodiment of the present invention, Figure 3 is a longitudinal sectional view of the longitudinal displacement adjustment assembly provided by an embodiment of the present invention, combined with Figure 2 and Figure 3As shown, each longitudinal displacement adjustment assembly 3 includes an upper connecting plate 31, a lower connecting plate 32, a force transmission shaft 33, two guide sleeves 34, two threaded sleeves 35 and an elastic member 36. The top surface of the upper connecting plate 31 is fixed to the bottom surface of the main beam 1, and the bottom surface of the upper connecting plate 31 has two spaced bosses 311, which are slidably sleeved on both ends of the force transmission shaft 33 along the axial direction of the force transmission shaft 33. The bottom surface of the lower connecting plate 32 is fixed to the pier 2 and is located between the two supports 4. The top surface of the lower connecting plate 32 has two spaced stoppers 321, and the two ends of the force transmission shaft 33 are respectively inserted into the corresponding stoppers 321. 21, each stop block 321 is arranged at intervals with the corresponding boss 311 to limit the position after the boss 311 slides, the two guide sleeves 34, the two threaded sleeves 35 and the elastic member 36 are all located between the two bosses 311, the elastic member 36 is sleeved on the power transmission shaft 33 and clamped between the two threaded sleeves 35, the two threaded sleeves 35 are both sleeved on the power transmission shaft 33, each guide sleeve 34 is slidably sleeved on the corresponding threaded sleeve 35, one end of each guide sleeve 34 is abutted against the corresponding boss 311, and the other end of each guide sleeve 34 is abutted against the elastic member 36 to drive the elastic member 36 to compress.

[0047] In the multi-span continuous bridge temperature deformation control system provided by the embodiment of the present invention, the longitudinal displacement adjustment assembly 3 is installed on the corresponding bridge pier 2. Because the elastic member 36 is mounted on the force transmission shaft 33 and sandwiched between two threaded sleeves 35, the threaded sleeves 35 limit the ends of the elastic member 36, and the corresponding guide sleeve 34 can compress the elastic member 36 to the left or right. In addition, the top surface of the upper connecting plate 31 is fixed to the bottom surface of the main beam 1. The bottom surface of the upper connecting plate 31 has two spaced-apart bosses 311, which are slidably mounted on both ends of the force transmission shaft 33 along the axial direction. When the pier 2 is at a position corresponding to the main beam and deforms, the bosses 311 move along the force transmission shaft 33 and compress the elastic member 36 through the guide sleeve 34, causing the elastic member 36 to be compressed. The restoring force generated by the elastic member 36 can regulate the deformation of the main beam. When the deformation is too large, the bosses 311 move to contact the stopper 321, achieving a hard limit on the upper connecting plate 31, thereby regulating the deformation of the main beam through the stopper 321.

[0048] During elevated temperatures, the corresponding longitudinal displacement adjustment assembly 3 on the main beam expands away from the center of the beam. This causes the main beam to move the upper connecting plate 31 and boss 311 to the right. As the left boss 311 moves rightward, it compresses the elastic member 36, which exerts a leftward force on the boss 311 and upper connecting plate 31, regulating the rightward expansion and deformation of the main beam. Furthermore, when the temperature rises excessively, the main beam drives the upper connecting plate 31 and boss 311 to the right, until they come into contact with the right stop 321, achieving a hard limit and thus similarly regulating deformation of the main beam.

[0049] Similarly, when the temperature drops, the position of the corresponding longitudinal displacement adjustment assembly 3 on the main beam contracts toward the center of the main beam. This means the main beam drives the upper connecting plate 31 and boss 311 to the left. As the right boss 311 moves leftward, it compresses the elastic member 36, which exerts a rightward force on the boss 311 and upper connecting plate 31, regulating the leftward contraction of the main beam. When the temperature drops excessively, the main beam drives the upper connecting plate 31 and boss 311 to the left until they contact the left stop 321, achieving a hard limit, thus similarly regulating main beam deformation.

[0050] That is to say, the temperature deformation control system for a multi-span continuous bridge provided by an embodiment of the present invention can control the temperature deformation of an already built and open bridge by setting a longitudinal displacement adjustment component 3, thereby adapting to the deformation of the beam end expansion device without changing the structure of the already built bridge.

[0051] Exemplarily, the number of the force transmission shafts 33 is 2, and the number of the bosses 311 and the blocks 321 is 4, that is, one force transmission shaft 33 corresponds to two bosses 311 and two blocks 321 , thereby achieving reliable support for the upper connecting plate 31 .

[0052] Continue to see Figure 3 An inner flange 341 is provided on the inner circumferential wall of one end of each guide sleeve 34. Each inner flange 341 is located between the corresponding boss 311 and the corresponding threaded sleeve 35, and each inner flange 341 is slidably engaged with the power transmission shaft 33. The inner flange 341 supports and guides one end of the guide sleeve 34.

[0053] In this embodiment, an adjusting bolt 37 can be movably inserted into each stopper 321 . Each adjusting bolt 37 is coaxially arranged with the force transmission shaft 33 , and one end of each adjusting bolt 37 abuts against the force transmission shaft 33 .

[0054] In the above embodiment, the adjusting bolt 37 can push the force transmission shaft 33, so that the force transmission shaft 33 moves along its axial direction until the distances between the boss 311 and the corresponding block 321 are equal (that is, the gaps between the corresponding boss 311 and the block 321 are equal), thereby ensuring that the two bosses 311 are symmetrically arranged relative to the two blocks 321 during the installation of the longitudinal displacement adjustment component 3, thereby achieving equal regulation of expansion and contraction.

[0055] Similarly, each stopper 321 is provided with an adjustment plate 39 on the side facing the boss 311, and each adjustment plate 39 is detachably mounted on the force transmission shaft 33, so that the gaps between the corresponding bosses 311 and the stoppers 321 can be made equal by inserting the adjustment plates 39, making the operation simpler.

[0056] In addition, each longitudinal displacement adjustment assembly 3 also includes two force transmission sleeves 38, each force transmission sleeve 38 is slidably mounted on the force transmission shaft 33, the force transmission sleeve 38 is located between the corresponding threaded sleeve 35 and the elastic member 36, and the other end of each guide sleeve 34 is against the corresponding force transmission sleeve 38.

[0057] In the above embodiment, the force transmission sleeve 38 transmits force to the guide sleeve 34 , which can increase the contact area of the guide sleeve 34 with the elastic member 36 , making the elastic force of the guide sleeve 34 on the elastic member 36 more uniform.

[0058] For example, the elastic member 36 may be a plurality of disc springs, which have a reliable structure, a high elastic coefficient, and a better control effect on the thermal deformation of the bridge.

[0059] Figure 4 This is a flow chart of a design method for a temperature deformation control system for a multi-span continuous bridge provided by an embodiment of the present invention. Figure 4 As shown, the design method is based on the above-mentioned temperature deformation control system for a multi-span continuous bridge, and the design method includes:

[0060] S1. Determine a temperature deformation adjustment target for the main beam 1 , where the temperature deformation adjustment target includes a corresponding position of the main beam 1 and a temperature deformation range of the main beam 1 .

[0061] S2. Calculate the position of the target temperature deformation zero point of the main beam 1 and calculate the design displacement and bearing capacity of the longitudinal displacement adjustment component 3.

[0062] The designed displacement is the gap between the corresponding boss 311 and the stopper 321 .

[0063] S3. Based on the design displacement, bearing capacity and corresponding installation space of the longitudinal displacement adjustment component 3, corresponding longitudinal displacement adjustment components 3 are installed on the piers 2 adjacent to the target temperature deformation zero point of the main beam 1.

[0064] The design method of a temperature deformation control system for a multi-span continuous bridge provided in an embodiment of the present invention can not only control the temperature deformation of a built and open bridge by setting a longitudinal displacement adjustment component 3, but also can set two adjacent longitudinal displacement adjustment components 3 accordingly, thereby adjusting the temperature deformation of the bridge, that is, adjusting the position of the temperature deformation zero point of the main beam 1, thereby meeting the requirements of the temperature deformation adjustment target of the main beam 1.

[0065] In this embodiment, the position of the target temperature deformation zero point of the main beam is calculated using the following formula:

[0066] ΔL=α*Δt*L; (1)

[0067] Among them, △L is the expansion and contraction of the main beam, α is the expansion coefficient of the main beam, △t is the temperature change, and L is the distance between the position of the target temperature deformation zero point of the main beam and the corresponding position of the main beam.

[0068] In addition, the load-bearing capacity is calculated as follows:

[0069] f0+ f1+…+f i +k*x i = f i+1 +k*x i+1 + f i+2 +…+ f n +T; (2)

[0070] n is the total number of piers. The longitudinal displacement adjustment components are set on the i-th pier and the i+1-th pier. The target temperature deformation zero point of the main beam is located between the i-th pier and the i+1-th pier. f0, f1, ..., f i ,…,f n is the friction force between each support and the main beam, and the friction force between each support and the main beam is equal, k is the elastic coefficient of the elastic member, T is the bearing capacity of the longitudinal displacement adjustment assembly on the i+1th pier, x i is the deformation of the elastic member of the longitudinal displacement adjustment assembly on the i-th pier, x i+1 is the deformation of the elastic member of the longitudinal displacement adjustment assembly on the i+1th pier.

[0071] It is easy to understand that the above formula (2) is based on the fact that the forces acting on the main beams on both sides are balanced at the position of the target temperature deformation zero point of the main beam.

[0072] Exemplarily, the elastic modulus of the elastic member is 1000-1500 kN / cm.

[0073] The above design method is described below with reference to specific embodiments:

[0074] like Figure 5 A railway bridge has nine spans, with prestressed concrete box girders and solid concrete piers. The spans of the multi-span continuous beam are: l1, l9 = 48m, l2 - l8 = 80m. Both ends of the continuous beam are connected to a simply supported concrete beam with a standard span of 32m, l0.

[0075] Step 1: To improve railway operational safety and transportation efficiency, and to eliminate the problem of track damage caused by excessive thermal deformation at the beam ends of curved sections, the thermal deformation adjustment target for the main beam is: the thermal deformation on the right side of the simply supported beam next to the main beam at pier 9 does not exceed 30 mm.

[0076] Step 2: The temperature variation at the bridge site is ±15°C (i.e., the temperature variation Δt is ±15°C), and the main beam expansion coefficient α is 0.00001. Calculate the temperature span using formula (1): ΔL = (30) / (0.00001 / ×15) = 200m, and L2 = ΔL - l0 = 200 - 32 = 168m. This means the target temperature deformation zero point is located exactly between piers 6# and 7#.

[0077] Step 3: Based on the principle of deformation coordination, the bridge span between piers 6# and 7# is l7 = 80m. When the temperature variation is ±15°C, the main beam length between piers 6# and 7# varies by ±12mm based on formula (1). To ensure that the zero point of temperature deformation is located at the mid-span under the ±15°C working condition (the distance between the two piers and the target temperature deformation zero point corresponds to the ±12mm change in the main beam length between piers 6# and 7#), the corresponding design displacement e of the longitudinal displacement adjustment component is 6mm (because the target temperature deformation zero point is located in the middle of the two piers, the gap between the corresponding boss and the stopper is 6mm).

[0078] , considering the stiffness of pier ⑥# and pier ⑦#, the design displacement k corresponding to the longitudinal displacement adjustment component is 1200kN / cm. When the temperature rise and fall corresponding to the bridge is the largest, it is the most unfavorable working condition. At this time, according to formula (2), f0+f1+f2+f3+f4+f5+f6+k*x6=f7+k*x7+T+f8+f9;

[0079] Among them, f0, f1, f2, f3, f4, f5, f6, f7, f8, and f9 are all equal. According to formula (1), the deformation of the main beam at piers 6# and 7# is x6 and x7, respectively, which are 6 mm. The friction between each support and the main beam is 0.03, and the vertical bearing capacity of each support is designed to be 35000 kN. When the actual vertical bearing capacity of each support is calculated as 0.8 times the vertical bearing capacity, and one pier corresponds to two supports, then T = 4f i =4*2*0.03*0.8*35000=6720kN, the corresponding bearing capacity is 7000kN.

[0080] Step 4: According to the on-site measurement data, there is a large plane space between the two supports, which meets the conditions for installing the longitudinal displacement adjustment component. The height from the top of the pier to the bottom of the beam is 60 cm, and the installation height of the longitudinal displacement adjustment component is 60±3 cm. The longitudinal displacement adjustment component is installed based on the design displacement and bearing displacement.

[0081] The following is a detailed description of the displacement of the zero point of temperature deformation of the above-mentioned bridge under the conditions of temperature increase and decrease, with reference to the accompanying drawings, as follows:

[0082] Figure 6 : is a schematic diagram of the change of the deformation zero point corresponding to the bridge under the temperature rising condition provided by the embodiment of the present invention, such as Figure 6 As shown in Figure 1, for the temperature rise condition, the deformation is divided into two stages: the first stage: when the temperature rises by 3°C, the deformation zero point moves from the mid-span of the full span to Pier 7#, and Pier 7# elastically displaces to 6 mm (calculated by formula (1)), forming a fixed limit. The second stage: when the temperature continues to rise to 15°C, the deformation zero point shifts from Pier 7# to the mid-span of Piers 6-7.

[0083] Figure 7 : is a schematic diagram of the change of the deformation zero point corresponding to the bridge under the cooling condition provided by the embodiment of the present invention, such as Figure 7 As shown in the figure, in the first stage, when the temperature drops by 3°C, the deformation zero point moves from the middle of the full span to Pier 7#, and the elastic displacement of Pier 7# reaches 6mm, forming a fixed limit. In the second stage, when the temperature continues to drop to 15°C, the deformation zero point moves from Pier 7# to the middle of the span between Piers 6 and 7.

[0084] In other words, this design method can not only regulate the temperature deformation of an already built and open bridge by setting a longitudinal displacement adjustment component, but also adjust the temperature deformation of the bridge by setting two adjacent longitudinal displacement adjustment components in coordination, that is, adjusting the position of the temperature deformation zero point of the main beam, thereby meeting the requirements of the temperature deformation adjustment target of the main beam.

[0085] It will be easily understood by those skilled in the art that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A temperature deformation control system for a multi-span continuous bridge, characterized in that: The multi-span continuous bridge temperature deformation control system comprises a main beam (1), a plurality of bridge piers (2) and at least one longitudinal displacement adjustment component (3); Each of the bridge piers (2) is provided with two spaced-apart supports (4), and the main beam (1) is arranged on a plurality of the supports (4); Each of the longitudinal displacement adjustment components (3) includes an upper connecting plate (31), a lower connecting plate (32), a force transmission shaft (33), two guide sleeves (34), two threaded sleeves (35) and an elastic member (36). The top surface of the upper connecting plate (31) is fixed to the bottom surface of the main beam (1). The bottom surface of the upper connecting plate (31) has two spaced bosses (311). The two bosses (311) are slidably mounted on both ends of the force transmission shaft (33) along the axial direction of the force transmission shaft (33). The bottom surface of the lower connecting plate (32) is fixed to the pier (2) and is located between the two supports (4). The top surface of the lower connecting plate (32) has two spaced stoppers (321). The two ends of the force transmission shaft (33) are respectively inserted into the corresponding stoppers (321). The stopper (321) is spaced apart from the corresponding boss (311) to limit the position after the boss (311) slides. The two guide sleeves (34), the two threaded sleeves (35) and the elastic member (36) are all located between the two bosses (311). The elastic member (36) is sleeved on the force transmission shaft (33) and clamped between the two threaded sleeves (35). The two threaded sleeves (35) are sleeved on the force transmission shaft (33). Each guide sleeve (34) is slidably sleeved on the corresponding threaded sleeve (35). One end of each guide sleeve (34) is against the corresponding boss (311), and the other end of each guide sleeve (34) is against the elastic member (36) to drive the elastic member (36) to compress.

2. The temperature deformation control system for a multi-span continuous bridge according to claim 1 is characterized in that: An inner flange (341) is provided on the inner peripheral wall of one end of each guide sleeve (34), and each inner flange (341) is located between the corresponding boss (311) and the corresponding threaded sleeve (35), and each inner flange (341) is in sliding engagement with the force transmission shaft (33).

3. The temperature deformation control system for a multi-span continuous bridge according to claim 1 is characterized in that: An adjusting bolt (37) can be movably inserted into each of the stoppers (321), each of the adjusting bolts (37) is coaxially arranged with the force transmission shaft (33), and one end of each of the adjusting bolts (37) abuts against the force transmission shaft (33).

4. The temperature deformation control system for a multi-span continuous bridge according to claim 1 is characterized in that: Each of the longitudinal displacement adjustment assemblies (3) further comprises two force transmission sleeves (38), each of the force transmission sleeves (38) being slidably sleeved on the force transmission shaft (33), the force transmission sleeve (38) being located between the corresponding threaded sleeve (35) and the elastic member (36), and the other end of each of the guide sleeves (34) being in contact with the corresponding force transmission sleeve (38).

5. A temperature deformation control system for a multi-span continuous bridge according to any one of claims 1 to 4, characterized in that: An adjustment plate (39) is provided on one side of each stopper (321) facing the boss (311), and each adjustment plate (39) is detachably sleeved on the force transmission shaft (33).

6. A temperature deformation control system for a multi-span continuous bridge according to any one of claims 1 to 4, characterized in that: The elastic member (36) is a plurality of disc springs.

7. A design method for a temperature deformation control system for a multi-span continuous bridge, characterized in that: The design method is based on a temperature deformation control system for a multi-span continuous bridge according to any one of claims 1 to 6, and the design method includes: Determining a temperature deformation adjustment target of the main beam (1), wherein the temperature deformation adjustment target includes a corresponding position of the main beam (1) and a temperature deformation range of the main beam (1); Calculating the position of the target temperature deformation zero point of the main beam (1), and calculating the design displacement and load-bearing capacity of the longitudinal displacement adjustment component (3), wherein the design displacement is the gap between the corresponding boss (311) and the stopper (321); Based on the designed displacement, load-bearing capacity and corresponding installation space of the longitudinal displacement adjustment component (3), corresponding longitudinal displacement adjustment components (3) are provided on the bridge piers (2) adjacent to the target temperature deformation zero point of the main beam (1).

8. The design method of a temperature deformation control system for a multi-span continuous bridge according to claim 7 is characterized in that: The position of the target temperature deformation zero point of the main beam (1) is calculated using the following formula: ΔL=α*Δt*L; Wherein, ΔL is the expansion and contraction amount of the main beam (1), α is the expansion and contraction coefficient of the main beam (1), Δt is the temperature change amount, and L is the distance between the position of the target temperature deformation zero point of the main beam (1) and the corresponding position of the main beam (1).

9. The design method of a temperature deformation control system for a multi-span continuous bridge according to claim 7 is characterized in that: The load-bearing capacity is calculated as follows: f0+f1+…+f i +k*x i =f i+1 +k*x i+1 +f i+2 +…+f n +T; n is the total number of the bridge piers (2), the longitudinal displacement adjustment assembly (3) is provided on the i-th bridge pier (2) and the i+1-th bridge pier (2), the target temperature deformation zero point of the main beam (1) is located between the i-th bridge pier (2) and the i+1-th bridge pier (2), f0, f1, ..., f i ,…,f n is the friction force between each of the supports (4) and the main beam (1), and the friction forces between each of the supports (4) and the main beam (1) are equal, k is the elastic coefficient of the elastic member (36), T is the bearing capacity of the longitudinal displacement adjustment assembly (3) on the i+1 th pier (2), x i is the deformation of the elastic member (36) of the longitudinal displacement adjustment assembly (3) on the i-th bridge pier (2), x i+1 is the deformation amount of the elastic member (36) of the longitudinal displacement adjustment assembly (3) on the (i+1) th bridge pier (2).

10. The design method of a temperature deformation control system for a multi-span continuous bridge according to claim 9, characterized in that: The elastic coefficient of the elastic member (36) is 1000-1500 kN / cm.

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