CN220598198U - A beam body reinforcement and support replacement device - Google Patents

Abstract

The utility model relates to a beam body reinforcing and support replacing device, wherein a pre-pressing limiting spring support comprises a sleeve and a rubber compound spring; the inner wall of the sleeve is correspondingly provided with a supporting block which is in butt joint with the spring lower pressing plate; one end of a nut anti-loosening spring is arranged on the spring lower pressing plate, and the other end of the nut anti-loosening spring is arranged on the nut; the nut is in threaded connection with one end of the spring pre-pressing bolt, and the other end of the spring pre-pressing bolt extends out of the opening of the spring lower pressing plate to be connected with one end face of the spring upper pressing plate; the rubber compound spring is arranged between the spring upper pressing plate and the spring lower pressing plate, the guide ring is arranged on the spring upper pressing plate, the corresponding connecting lug plate is arranged on the upper pressing plate, the cover plate is arranged at the other end of the sleeve, and the corresponding connecting lug plate is arranged on the cover plate; the two connecting lug plates supported by the pre-pressing limiting spring are respectively arranged on the lower end surface of the beam and the side wall of the middle pier through connecting pieces. The utility model has good bending and shearing resistant effect and can realize rapid beam body reinforcement and support replacement.

Description

A beam body reinforcement and support replacement device

Technical field

The invention relates to the field of bridge repair, reconstruction and reinforcement, and in particular to a bridge beam reinforcement and support replacement device and a repair method.

Background technique

Due to overloading of traffic bridges, a large number of bridges have suffered shear damage, reduced bending stiffness, and weakened beam load-bearing capacity. It is necessary to take emergency bending and shear reinforcement and beam jacking support replacement measures in a timely and rapid manner. Since the shear bearing capacity is directly related to the beam height, the original damaged area is relatively hidden and difficult to directly lift or reinforce. On the one hand, the height limit, width limit, and load limit operation methods are usually used to further strengthen monitoring and inspection efforts. On the other hand, the commonly used reinforcement methods include adding corbels, so that the undamaged beam segments continue to bear the burden of operation, but the improvement in bending resistance is limited. ; Or add diagonal braces for reinforcement to enhance shear resistance. At the same time, the span can be reduced, the mid-span bending moment can be reduced, and the bending resistance can be improved. However, adding more rigid diagonal braces can easily lead to the shear resistance of the new support section not meeting the requirements. , bringing new risks. At the same time, there are no standardized methods and components, making installation difficult, time-consuming and labor-intensive. Based on the above shortcomings, a rapid process flow and device for beam reinforcement and support replacement with good comprehensive effects of bending and shear resistance are proposed.

Contents of the invention

In view of the technical problems existing in the background art, the present invention provides a beam body reinforcement and support replacement device and a rapid process flow with good comprehensive effects of bending resistance and shear resistance. In order to achieve the above objects, the present invention provides the following technical solutions:

A beam body reinforcement and support replacement device, including a preloaded limit spring support; the preloaded limit spring support includes a sleeve and a rubber composite spring;

The inner wall of the sleeve is provided with more than two support blocks, and the support blocks are docked with the spring lower pressure plate; the center of the spring lower pressure plate is provided with an opening that can accommodate the movement of the spring preload bolt along the length direction of the sleeve; the nut One end of the anti-loosening spring is installed on one end of the spring lower pressure plate close to the support block, and the other end of the nut anti-loosening spring is installed on the nut; the nut is threadedly connected to one end of the spring preload bolt, and the other end of the spring preload bolt extends out of the spring lower pressure plate The opening is connected to one end of the spring upper pressure plate; the rubber composite spring is installed between the spring upper pressure plate and the spring lower pressure plate, the spring upper pressure plate is equipped with a guide ring, and the other end of the sleeve is equipped with a cover plate;

The upper pressure plate and sleeve cover plate supported by the preloaded limit spring are respectively installed on the lower end surface of the beam and the side wall of the middle pier through connectors.

Corresponding connecting ear plates are installed on the upper pressure plate and the cover plate, and corresponding connecting ear plates are installed on the cover plate; the two connecting ear plates supported by the preload limit spring are installed under the beam through connectors. on the end faces and side walls of the central pier.

The preloaded limit spring support is arranged at an angle; the connecting piece adopts an anchor plate; the two connecting ear plates are respectively installed on the inner side of the middle pier and the lower end surface of the beam through corresponding anchor plates.

The preloaded limit spring support is arranged vertically. The upper end of the preloaded limit spring support is a flat end, and a corresponding connecting ear plate is installed on the cover plate at the lower end; the connector connected to the inside of the middle pier includes a support frame and two An anchor plate; the support frame is V-shaped, one end of the support frame is set horizontally, one end of the end face is connected to the connecting lug plate at the lower end of the preloaded limit spring support, and the other end of the end face is connected to the One end is respectively installed on the inner surface of the middle pier.

The connector connected to the lower end face of the beam adopts anchor plate.

A steel beam is installed transversely below each beam; the upper end of each preloaded limit spring support is connected to the steel beam through a steel beam stiffening plate.

The beam body reinforcement and support replacement device also includes a jacking rod; the jacking rod is composed of a vertical plate and an end plate; the end plate is installed above the vertical plate, and a jack for lifting the beam is installed above the end plate; The vertical plate is detachably installed on the connecting piece on the side wall of the middle pier.

A rapid process flow for beam reinforcement and support replacement devices. The rapid process flow includes the following steps:

(1) Test and preload the performance of the preloaded spring in the preloaded limit spring support. The preloaded limit spring support can provide a constant reaction force of 20-30kN/support, with a stiffness of 0.5-1kN/mm. The specific stiffness , the constant value can be determined based on the beam load and structural analysis;

(2) The cavity at the beam end is filled with high-strength cement-based materials. A small hole with a diameter of 2cm is drilled at the bottom of the beam. Foaming materials and cement-based materials are poured into the mid-span and beam ends successively;

(3) Install the corresponding anchor plate on the inner side of the middle pier and the lower end surface of the beam through anchor bolts and structural glue. Install the jacking rod on the anchor plate inner side of the middle pier. Use the jack to lift the lower end face of the beam to adjust the beam end. height, install a rubber bearing to support the beam on the upper end face of the pier, so that the beam end is stressed from the new support position, so that there is no gap between the rubber bearing and the bottom of the beam. Use 2 jacks to lift the same beam at the same end at the same time. rise until the pad is satisfied;

(4) Remove the vertical plate, end plate and jack in step (3), install two preloaded limit spring supports on one end of the single beam as needed, and hinge the two connecting ear plates to the corresponding anchor plates with bolts superior.

Preferably, the cement-based material has a water-cement ratio in the range of 0.26-0.28, a flow rate in a range of 10-17s, a 3h free expansion rate greater than 0.02%, a 3d pressure resistance of 40MPa, and a 28d pressure resistance of 50MPa; the foaming material is lightweight. Material.

Preferably, the rubber bearing uses a high-strength mortar pad. The size specifications of the high-strength mortar pad can be determined by reference to the original design or according to load and deformation requirements. For example, the case project is a 200*200*20mm rubber plate.

The beneficial effects of the present invention are:

1. The present invention provides oblique pre-loaded limit spring supports at the lower end of the beam and the side wall of the middle pier to provide a constant reaction force to the support point, thereby unloading the shear force at the beam end and reducing the mid-span bending moment;

2. The present invention is provided with a vertical pre-loaded limit spring support and a matching support frame. The force exerted by the pre-loaded limit spring support on the upper beam body is vertical and upward. For the beam body that is simply supported at both ends, no support will be caused. The horizontal force of the seat part is reduced, and the support frame adopts an integral structure, which improves the overall performance and simplifies the installation difficulty;

3. If the original support at the beam end cannot function, use rubber bearings (plates) to pad the new support position of the beam end, and use diagonal support embedded component reaction points and jacks to adjust the height of the beam end and pad the support position;

4. The cavity at the beam end is filled with high-strength cement-based materials to improve the overall and local shear strength of this section;

5. The present invention does not increase damage to the bridge, increases the self-weight load only slightly, does not cause new unfavorable sections after reinforcement, and provides comprehensive reinforcement for all sections of the entire bridge. The plan is comprehensive, ranging from bearing replacement, shear reinforcement, The capacity improvement goals have been achieved, and the bridge has returned to the design load requirements;

6. The reinforcement of the present invention is flexible and can be used to reinforce a single-piece beam, one end of a single-piece beam, or multiple beams at the same time, and can also be extended to T-shaped beams and other types of beam bridges;

7. This invention is completed from the whole process of idea, design, manufacturing, installation and test inspection. The test and operation conditions show that the solution meets social needs, has great promotion significance, has low economic investment, does not require large hoisting equipment, and does not require maintenance during the process. Increase traffic control.

Description of the drawings

Figure 1 is a schematic structural diagram of the beam reinforcement and support replacement device of the present invention (preloaded limit spring support tilted arrangement);

Figure 2 is a schematic diagram of the internal structure of the preloaded limit spring device in Figure 1;

Figure 3 is a schematic diagram of the position and structure of the anchor plate in Figure 1;

Figure 4 is a schematic diagram of the position and structure of the jack in Figure 1;

Figure 5 is a schematic structural diagram of the beam reinforcement and support replacement device of the present invention (the preloaded limit spring support is installed vertically);

Figure 6 is a schematic structural diagram of the beam reinforcement and support replacement device of the present invention (preloaded limit spring supports are installed vertically and steel beams are added);

FIG. 7 is a side view of FIG. 6 .

In the picture, 1-preloaded limit spring support, 2-sleeve, 3-rubber composite spring, 4-support block, 5-spring lower pressure plate, 6-nut, 7-nut anti-loosening spring, 8-spring preload Bolt, 9-spring upper pressure plate, 10-guide ring, 11-connecting ear plate, 12-beam, 13-middle pier, 14-anchoring plate, 15-support frame, 16-steel beam, 17-steel beam stiffening plate, 18-jacking rod, 19-vertical plate, 20-end plate, 21-rubber bearing, 22-jack, 23-high-strength cement-based material, 24-light foam material, 25-high-strength cement-based material grouting port, 26-lightweight foam material grouting port, 27-steel beam installation anchor plate, 28-cover plate, 29-double ear plate.

Detailed ways

Example 1:

As shown in Figures 1 to 4, a beam reinforcement and support replacement device includes a preloaded limit spring support 1;

The preloaded limit spring support 1 includes a sleeve 2 and a rubber composite spring 3;

The inner wall of the sleeve 2 is provided with more than two support blocks 4. The support blocks 4 are docked with the spring lower pressure plate 5 to bear the pressure transmitted by the spring lower pressure plate 5; there is a center of the spring lower pressure plate 5 that can accommodate the spring preload bolt 8 along the sleeve. The opening for movement in the length direction of the barrel 2; one end of the nut anti-loosening spring 7 is installed on one end of the spring lower pressure plate 5 close to the support block 4, and the other end of the nut anti-loosening spring 7 is installed on the nut 6; the nut 6 and the spring preload bolt 8 One end is threaded, and the other end of the spring preload bolt 8 extends out of the opening of the spring lower pressure plate 5 and is connected to one end of the spring upper pressure plate 9; the rubber composite spring 3 is installed between the spring upper pressure plate 9 and the spring lower pressure plate 5, and the spring upper pressure plate 9 9. A guide ring 10 is installed, and a corresponding connecting ear plate 11 is installed on the upper pressure plate. A cover plate is installed on the other end of the sleeve 2, and a corresponding connecting ear plate 11 is installed on the cover plate;

The two connecting ear plates 11 of the preloaded limit spring support 1 are respectively installed on the lower end surface of the beam 12 and the side wall of the middle pier 13 through connectors.

The preloaded limit spring support 1 is arranged at an angle; the connector adopts the anchor plate 14; the two connecting ear plates 11 are respectively installed on the inner side of the middle pier 13 and the lower end surface of the beam 12 through the corresponding anchor plates 14. Since the preloaded limit spring support 1 is used for rapid emergency response, it plays a relatively long-term role in recovery and improvement. The constant force provided by the preloaded limit spring support 1 can supplement the decrease in bearing capacity caused by damage to the bending and shearing sections. Can share the load upgrade part.

When the wheel is transmitted to the support point of the preload limit spring support 1 through the beam body, and the load is less than the preload value of the rubber composite spring 3, the internal force of the spring preload bolt 8 decreases, but the internal force of the rubber composite spring 3 remains unchanged. The deformation of spring 3 does not increase, and the internal force of the diagonal brace sleeve 2 is equal to the load force; when the wheel is transmitted to the preload limit spring support 1 through the beam 12 and the load tends to exceed the preload value of the rubber composite spring 3, the spring preload bolt 8. The internal force decreases and approaches zero, and the deformation of the rubber composite spring 3 tends to increase. The spring upper pressure plate 9 and the bolt move toward the cover plate of the sleeve 2. The nut 6 relaxes the spring and stretches it. The internal force of the diagonal brace is equal to the total deformation of the spring. Internal force.

Example 2:

As shown in Figures 2 and 5, the preloaded limit spring support 1 includes a sleeve 2 and a rubber composite spring 3;

The inner wall of the sleeve 2 is provided with more than two support blocks 4, and the support blocks 4 are docked with the spring lower pressure plate 5; the center of the spring lower pressure plate 5 is provided with an opening that can accommodate the movement of the spring preload bolt 8 along the length direction of the sleeve 2; One end of the nut anti-loosening spring 7 is installed on an end surface of the spring lower pressure plate 5 close to the support block 4, and the other end of the nut anti-loosening spring 7 is installed on the nut 6; the nut 6 is threadedly connected to one end of the spring preload bolt 8, and the spring preload bolt 8 The other end extends out of the opening of the spring lower pressure plate 5 and is connected to one end surface of the spring upper pressure plate 9; the rubber composite spring 3 is installed between the spring upper pressure plate 9 and the spring lower pressure plate 5. The spring upper pressure plate 9 is equipped with a guide ring 10, and the upper pressure plate The upper end is a flat end, and the corresponding connecting ear plate 11 is installed on the cover plate at the lower end. The other end of the sleeve 2 is installed with a cover plate, and the corresponding connecting ear plate 11 is installed on the cover plate;

The two connecting ear plates 11 of the preloaded limit spring support 1 are respectively installed on the lower end surface of the beam 12 and the side wall of the middle pier 13 through connectors.

The anchor plate 14 is used as the connector connected to the lower end surface of the beam 12 . The connector connected to the inner side of the middle pier 13 includes a support frame 15 and two anchor plates 14; the support frame 15 is V-shaped, with one end face set horizontally, and one end of the end face is connected to the lower end of the preloaded limit spring support 1 The connecting ear plate 11 is connected, and the other end of the end surface and one end of the other end surface are respectively installed on the inner side of the middle pier 13.

Compared with the first embodiment, the second embodiment adds a support frame 15. When the span of the beam 12 is larger, the slope of the oblique support becomes smaller, the vertical component force of the support becomes smaller and smaller, and the supporting role is limited. Therefore, this implementation For example, a V-shaped support frame 15 is invented, so that the vertical force of the preload spring can be fully exerted to the beam body, and the preload limit spring support 1 is arranged vertically; the force exerted by the preload limit spring support 1 on the upper beam body 12 is vertically upward. , for the beam body 12 simply supported at both ends, it will not cause horizontal force on the support part.

The support frame 15 adopts an integral structure, which improves the overall performance and simplifies the installation difficulty.

Embodiment three:

Since each span of the bridge is composed of multiple beams 12, the vehicle load acting on the bridge deck is relatively certain, and which beam 12 acts on it is random. However, the greater the load on some beams 12, the greater the damage, which is obviously a high-probability event. At the same time, the coordination and integrity between the beams 12 and adjacent beams 12 decrease.

On the basis of the second embodiment, as shown in Figures 2, 6, and 7, steel beams 16, steel beam stiffening plates 17, and steel beam installation anchor plates 27 are added laterally. The preloaded limit spring support in the second embodiment is The upper end of 1 is changed to a flat end. The flat end plate and the lower wing plate of the steel beam are bonded, welded or bolted with structural glue. The steel beam at the connection is strengthened with a steel beam stiffening plate. The steel beam stiffening plate 17 can exert its stiffness and improve the strength of each piece. The connection between the beams 12 enables the integrity of each beam 12 to be restored and improved, and the load pressure of a certain beam 12 is reduced; the connecting ear plate 11 at the other end of the pre-loaded limit spring support 1, through the double ear plate 29 Connected to support frame 15.

Since the lateral position of vehicles passing on the bridge 12 has a certain degree of randomness, the preloaded limit spring support 1 can be shared by the steel beam stiffening plate 17; at the same time, during the investigation and inspection process, it was found that the damage degree of each beam 12 was different. , the degree of damage to the connections between the 12 beams is different. The newly added steel beam stiffening plate 17 can strengthen the connection between the 12 beams in a targeted manner, and also strengthen the other 12 beams; the preloaded limit spring support 1 is reinforced to the damage For relatively serious parts, when the other 12 beams bear larger loads, the load can also be shared. On the one hand, adding cross beams 12 can appropriately reduce the number of preloaded limit spring supports 1 and improve the reinforcement efficiency of the entire span bridge; cross beams 12 can be hinged or full-length between beams 12 and 12. The beam 12 can also be finally simplified to a steel plate. The steel plate can also be pre-stressed in the transverse direction to improve the integrity between the beams 12. The pre-stressed steel plate can also be replaced by steel strands. Finally, the integrity of the entire span of the bridge, the total number of supports, and the location optimization were achieved.

In various embodiments of the present invention, the object of emergency bending resistance, shear reinforcement and beam 12 lifting support replacement measures is the hollow plate beam 12. If the object is a T-shaped beam 12 or a Π-shaped beam 12, the opposite support When there is a fracture or damage near the seat for reinforcement, you can use a quick-adhesion steel plate to reinforce the damaged part after jacking up and temporary padding; then use the reinforced beam body 12 to install pre-pressure limits on the sides of the webs of T and Π-shaped beams 12 Spring support 1.

In the present invention, the installation base and related components can be produced in a standardized manner, and the length of the sleeve 2 can be produced in a modular format of 10 or 20 cm to meet the needs of different bridges 12; in the third embodiment, the base can use an anchor plate 14, and the base can be installed Structural adhesive bonding + chemical anchor bolts can be combined. In rapid rescue operations, the fast-hardening high-strength structural adhesive can independently bear the vertical lifting capacity and the load of the entire structure; the anchor bolts can be implemented at the end of the rescue operation as a long-term support for the entire system. Safety reserve.

The working principle and process of the present invention are as follows:

(1) Test and preload the performance of the preloaded spring in the preloaded limit spring support 1. The preloaded limit spring support 1 can provide a constant reaction force of 20-30kN/support and a stiffness of 0.5-1kN/mm. According to It is necessary to set two preloaded limit spring supports 1 at one end of the single beam 12. The entire device can adopt anti-corrosion measures such as grease and paint to ensure the durability of the system;

(2) The cavity at end 12 of the beam is poured with high-strength cement-based material 23 to repair cracks, fractures and other defects in this section, and to improve the overall and local shear strength of this section. A small hole with a diameter of 2cm is drilled at the bottom of beam 12, as shown in Figure 1 There are grouting ports 25 for medium- and high-strength cement-based materials 23 and grouting ports 26 for lightweight foam materials 24. Foam materials and cement-based materials are successively poured into the mid-span and beam 12 ends;

(3) Due to bending and shear damage in the support area at the end of the beam 12, the beam body 12 sinks, the support cannot function in angular displacement, and the stress on the support point of the beam body 12 is unreasonable, so it needs to be leveled, and the corresponding anchor bolts and structural glue will be used. The anchor plate 14 is installed on the inner side of the middle pier 13 and the lower end surface of the beam 12. The lifting rod 18 is installed on the anchor plate 14 on the inner side of the middle pier 13. The jack 22 lifts the lower end surface of the beam 12 to adjust the height of the beam 12 end. Install the rubber bearing 21 to support the beam 12 on the upper end of the pier, so that the end of the beam 12 is stressed from the new support position, so that there is no gap between the rubber bearing 21 and the bottom of the beam 12. Use two jacks 22 at the same end of the same beam 12 At the same time, lift until the pad is satisfied.

(4) Remove the vertical plate 19, end plate 20 and jack 22 in step (3);

(5) Install the preloaded limit spring support 1 (Embodiment 1): Use bolts to hinge the two connecting ear plates 11 of the preloaded limit spring support 1 to the corresponding anchor plates 14;

(Embodiment 2): Install both ends of the V-shaped support frame 15 on the corresponding anchor plates 14 on the inside of the middle pier 13, and install a connecting ear plate 11 of the preloaded limit spring support 1 on the support frame 15 In the middle part, another connecting ear plate 11 is hinged on the corresponding anchor plate 14 at the lower end of the beam 12;

(Embodiment 3): Install the two ends of the V-shaped support frame 15 on the corresponding anchor plates 14 on the inner side of the middle pier 13, and install the steel beam 12 transversely below the beam body 12 through the steel beam installation anchor plate 47. The flat end plate at the upper end of the preloaded limit spring support 1 and the lower wing plate of the steel beam are bonded, welded or bolted with structural glue, and the steel beams at the connection are reinforced with steel beam stiffening plates 17 to improve the connection between the beams 12 , so that the integrity of each beam 12 can be restored and improved, and the load pressure of a certain beam 12 can be reduced; the connecting lug plate at the other end of the preloaded limit spring support 1 is connected to the support frame 29 through the double lug plate.

Among them, cement-based materials play a reinforcing role, and materials with low water-to-cement ratio and high fluidity are selected: the water-to-cement ratio range of cement-based materials is 0.26-0.28, the flow rate range is 10-17s, and the 3h free expansion rate is greater than 0.02 %, the 3d compression resistance can reach 40MPa, and the 28d compression resistance can reach 50MPa; the foaming material is made of lightweight materials, which mainly reduces the use of cement-based materials and prevents the cement-based materials filled in the middle from not playing a mechanical role, wasting costs and increasing self-weight. load and other adverse effects.

Among them, the rubber support 21 uses a high-strength mortar pad, which is a rubber plate with a size of 200*200*20mm.

First of all, if there is serious fracture or damage to the section near the support, the section cannot bear the vehicle load normally, or the support has aged and failed, after the column + jack 22 jacking process in this rapid process flow is implemented, the support point will be replaced with jack 22 , and add temporary rubber bearings 21 nearby to replace the failed permanent bearings, avoiding the damaged section and reducing the continued severe impact of the damaged section; then, pour high-strength cement-based materials 23 through the vicinity of the bearings and the bending and shearing sections, Seal the cracks in 12 sections of the damaged beam and fill the hollow parts to restore or improve the shear capacity to a certain extent; finally, install the preloaded limit spring support 1 and other components to further alleviate the internal force level of the bending and shear sections and improve the beam to a certain extent. The overall carrying capacity of the body 12.

Claims (7)

1. The utility model provides a roof beam body consolidates and support change device which characterized in that: comprises a prepressing limit spring support;

the pre-pressing limiting spring support comprises a sleeve and a rubber compound spring;

more than two supporting blocks are correspondingly arranged on the inner wall of the sleeve, and the supporting blocks are in butt joint with the spring lower pressing plate; an opening capable of accommodating the movement of the spring pre-pressing bolt along the length direction of the sleeve is formed in the center of the spring lower pressing plate; one end of a nut anti-loosening spring is arranged on one end face, close to the supporting block, of the spring lower pressing plate, and the other end of the nut anti-loosening spring is arranged on the nut; the nut is in threaded connection with one end of a spring pre-pressing bolt, and an opening, extending out of the spring lower pressing plate, of the other end of the spring pre-pressing bolt is connected with one end face of the spring upper pressing plate; the rubber compound spring is arranged between the spring upper pressing plate and the spring lower pressing plate, the spring upper pressing plate is provided with a guide ring, and the other end of the sleeve is provided with a cover plate;

the spring upper pressing plate and the sleeve cover plate supported by the pre-pressing limiting spring are respectively arranged on the lower end face of the beam and the side wall of the middle pier through connecting pieces.

2. The beam strengthening and carrier changing apparatus of claim 1, wherein:

corresponding connecting lug plates are respectively arranged on the spring upper pressing plate and the sleeve cover plate; the two connecting lug plates supported by the pre-pressing limiting spring are respectively arranged on the lower end face of the beam and the side wall of the middle pier through connecting pieces.

3. The beam strengthening and carrier changing apparatus of claim 2, wherein:

the pre-pressing limiting spring is supported and obliquely arranged; the connecting piece adopts an anchor plate; the two connecting lug plates are respectively arranged on the inner side of the middle pier and the lower end face of the beam through corresponding anchor plates.

4. The beam strengthening and carrier changing apparatus of claim 1, wherein:

the pre-pressing limiting spring support is vertically arranged, the upper end of the pre-pressing limiting spring support is a flat end, and the cover plate at the lower end is provided with a corresponding connecting lug plate; the connecting piece connected with the inner side of the middle pier comprises a supporting frame and two anchoring plates; the support frame is V-shaped, one end face of the support frame is horizontally arranged, one end of the end face is connected with a connecting lug plate at the lower end of the pre-pressing limiting spring support, and the other end of the end face and one end of the other end face are respectively arranged on the inner side face of the middle pier.

5. The beam strengthening and carrier changing apparatus of claim 4, wherein: the connecting piece connected with the lower end face of the beam adopts an anchor plate.

6. The beam strengthening and carrier changing apparatus of claim 4, wherein: steel beams are transversely arranged below the sheet beams; the upper ends of the pre-pressing limiting springs are arranged on the lower wing plates of the steel beams, and the steel beams at the joints are reinforced by steel beam stiffening plates; the lower ends of the precompressed limit springs are connected with the supporting frame through the double-lug plates.

7. The beam strengthening and carrier changing apparatus of claim 1, wherein: the lifting rod is also included;

the jacking rod consists of a vertical plate and an end plate; the end plate is arranged above the vertical plate, and a jack for jacking the beam is arranged above the end plate; the vertical plate is detachably arranged on the connecting piece on the side wall of the middle pier; the upper end face of the middle pier is provided with a rubber support for supporting the beam.