In-situ pier replacement and dismantling construction method for steel structure overpass

Abstract

The present invention relates to an in-situ pier replacement and dismantling construction method for a steel structure overpass. The method adopts an integrated bracket bottom plate design to replace a traditional cast-in-place concrete independent foundation, thereby improving on-site assembly efficiency. At the same time, a limit bracket is added for a cutting portion to ensure the structural stability of a beam body in a non-demolished section. The traditional hoop structure is optimized and an upper T-shaped wing plate structure system is added to provide a construction space for the jacking operation of a jack, thereby improving the safety of the demolished beam body in the stage of separating from a middle pier. An assembled annular steel wall is set up using the main body of the middle pier to be demolished, and support rods and a spray device are installed through the assembled annular steel wall, thereby effectively preventing sudden overturning and dust generated during the demolition of the middle pier, and achieving outstanding environmental benefits.

Description

Technical Field

[0001] The invention belongs to the field of municipal engineering, and in particular relates to an in-situ pier replacement and dismantling construction method for a steel structure overpass. Background Art

[0002] Elevated roads are the traffic arteries of modern metropolises, playing an irreplaceable role in improving traffic efficiency and alleviating urban traffic congestion. The main form of urban elevated roads is viaducts, but urban viaducts are different from general bridge construction. Their construction sites are often located in busy areas of cities with heavy traffic, surrounded by schools, residential areas, commercial areas, etc. Therefore, the construction of urban viaducts is subject to many restrictions such as site, traffic, construction period, and landscape.

[0003] When the construction of an elevated bridge conflicts with existing buildings, the economic feasibility of both the relocation of the elevated bridge route and the demolition and modification of existing buildings must be considered. For example, when the viaduct ramp pier conflicts with the existing pedestrian overpass, the cost of demolishing and modifying the existing pedestrian overpass is obviously much lower than the ramp relocation, but the new problem is how to minimize the economic losses of the demolition and modification of the pedestrian overpass, and even ensure that there is no impact on the original pedestrian route. Therefore, there is still a lot of room for optimization in the construction of elevated bridges in complex urban environments, which needs further discussion.

[0004] In view of this, there is an urgent need to invent a steel structure overpass demolition and reconstruction construction method with fast construction speed, low construction risk, and outstanding economic and technical benefits. Summary of the invention

[0005] The purpose of the present invention is to overcome the deficiencies in the prior art and provide a method for in-situ pier replacement and dismantling and reconstruction of a steel structure overpass.

[0006] The in-situ pier replacement and dismantling construction method of the steel structure overpass comprises the following steps:

[0007] S1. Set up temporary adjustable support brackets: Set up temporary adjustable support brackets at both ends of the demolished section beam body, and install limit brackets on both sides of the temporary adjustable support brackets on the non-demolished section beam body;

[0008] S2. Install the hoop body on the middle pier of the overpass where the beam of the demolished section is located, and install jacks on both sides of the hoop body. Use the jacks to symmetrically lift the beam of the demolished section, cut it and lift it away;

[0009] S3. Install an assembled annular steel wall on the middle pier, support it with a support rod wrapped with a spray pipe, break the middle pier and spray the spray pipe to reduce dust, and then lift it off the middle pier;

[0010] S4. Construct the pier pile foundation, pier cap and new ramp bridge pier from bottom to top;

[0011] S5. Install the pier bracket support on the pier of the newly built ramp bridge, hoist the newly built beam body onto the pier bracket support, clamp it with an L-shaped push plate, and then carry out welding operations.

[0012] Preferably, in step S1, the temporary adjustable support bracket includes an integrated support base plate, a temporary support bracket, a distribution beam and a limit bracket. The temporary support bracket is connected to the integrated support base plate by bolt anchoring. Reinforcing rods are arranged between the temporary support brackets. A distribution beam is arranged on the top of the temporary support bracket. Limit brackets are symmetrically arranged above both ends of the distribution beam, and auxiliary supports are symmetrically arranged in the middle.

[0013] Preferably, in step S1, the limiting bracket includes a bracket upright and a Y-shaped leg, and the bracket upright and the Y-shaped leg are both provided with adjusting bolts, and the end of the adjusting bolt is connected to a hinged guard plate, and the hinged guard plates are connected by a hinge shaft. The angle of the hinged guard plate is adjusted by the adjusting bolt to abut against the non-removable section beam body, and the adjusting bolt on the limiting bracket is adjusted to make the hinged guard plate abut against the non-removable section beam body, so as to prevent the non-removable section beam body from shifting during the cutting process.

[0014] Preferably, in step S2, T-shaped wing plates are symmetrically arranged on the main body of the clamp through supporting steel sections, the T-shaped wing plates on both sides are tensioned and anchored by tensioning screws, jacks are symmetrically arranged on the T-shaped wing plates on both sides, and fitting blocks are provided on the tops of the jacks to form a clamp-type micro-lifting bracket; after the demolished section beam body is symmetrically lifted and assisted to be separated by the jacks, the demolished section beam body within the range of the middle pier is cut according to the cutting line, and after cutting, it is lifted away from the site by a crane.

[0015] Preferably, in step S3, the clamp body is removed in advance, and the assembled annular steel wall is installed on the middle pier in the form of a clamp, which is divided into two or more groups, and the assembled annular steel wall is provided with two layers of plug-in buckles at equal intervals in the circumferential direction, and an upper support rod and a lower support rod are installed between the plug-in buckles on the assembled annular steel wall and the hinged supports pre-buried in the ground, and a spray pipe is provided on the lower support rod, and spray devices are provided on the spray pipe at equal intervals to form a pier column demolition anti-overturning dust reduction structure; the middle pier base and the middle pier pedestal are mechanically removed, and the spray pipe is used to spray dust reduction during the removal process, and the middle pier is pre-lifted by a crane after the removal, and then the plug-in buckles are released.

[0016] Preferably, in step S4, pier pile foundations, pier caps and newly built ramp bridge piers are constructed in sequence from bottom to top, the newly built ramp bridge piers pass through the newly built beam body of the overpass, and pier corbels are symmetrically arranged on both sides of the newly built ramp bridge piers.

[0017] Preferably, in step S5, the piers of the newly built ramp bridge are installed with I-beams using pier brackets to form pier bracket supports, the pier brackets on one side are installed with front and rear I-beams, upper I-beams and lower I-beams, the upper I-beams and lower I-beams are tensioned and anchored by vertical tension screws, the front and rear I-beams are connected by plug-in steel plates, the ends of the upper I-beams are provided with steel uprights, and thrusters are provided perpendicular to the inner sides of the steel uprights, the ends of the thrusters are connected with L-shaped thrust plates, the L-shaped thrust plates span the front and rear I-beams to form a lateral thrust installation bracket for the steel box girder; the newly built beam body is hoisted onto the pier bracket supports, the thrusters are simultaneously turned on, so that the L-shaped thrust plates on both sides clamp the newly built beam body, and finally the newly built beam body is welded; step S6 also exists after step S5: after the installation of the newly built beam body is completed, the bridge deck structure is constructed and the guardrail structure is restored.

[0018] The in-situ pier replacement and dismantling and reconstruction system for a steel structure overpass is obtained by any of the methods described above.

[0019] The beneficial effects of the present invention are:

[0020] 1) The present invention has developed a temporary adjustable support bracket, which adopts an integrated bracket bottom plate design to replace the traditional cast-in-place concrete independent foundation, thereby improving the on-site assembly efficiency. At the same time, a limit bracket is added for the cutting part to ensure the structural stability of the beam body in the non-demolition section.

[0021] 2) The present invention has developed a clamp-type micro-lifting bracket, which optimizes the traditional clamp structure and adds an upper T-shaped wing plate structure system to provide construction space for the jacking operation, thereby improving the safety of the demolished section beam when it is separated from the middle pier.

[0022] 3) The present invention has developed a pier column demolition anti-overturning and dust reduction structure, which uses the middle pier body to be demolished to set up an assembled annular steel wall, and installs support rods and spray devices through the assembled annular steel wall, which can effectively prevent sudden overturning and dust generated during the demolition of the middle pier, and has outstanding environmental benefits.

[0023] 4) The present invention has developed a lateral jacking installation bracket for steel box girders, which fully utilizes the brackets of newly built bridge piers to quickly build an I-beam foundation system, and applies lateral pressure to the newly built beam body through an L-shaped jacking plate, so that the cutout of the newly built beam body completely fits the newly built bridge piers, thereby improving the installation quality of the project. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a schematic diagram of the construction principle of the in-situ replacement of piers and dismantling and reconstruction of the steel structure overpass in the present invention;

[0025] Figure 2 It is a schematic diagram of the structure of the temporary adjustable support bracket in the present invention;

[0026] Figure 3It is a schematic diagram of the structure of the hoop-type micro-lifting support in the present invention;

[0027] Figure 4 It is a schematic diagram of the anti-overturning and dust reduction structure for pier removal in the present invention;

[0028] Figure 5 It is a schematic diagram of the side push installation bracket of the steel box girder in the present invention;

[0029] Figure 6 It is a schematic diagram of the construction process of in-situ pier replacement, dismantling and reconstruction of a steel structure overpass in the present invention.

[0030] In the figure: 1-guardrail; 2-beam body of non-removable section; 3-Y-shaped leg; 4-adjusting bolt; 5-hinged guard plate; 6-hinge shaft; 7-support pole; 8-auxiliary support; 9-distribution beam; 10-reinforcement rod; 11-temporary support bracket; 12-integrated bracket bottom plate; 13-matching block; 14-jack; 15-T-shaped wing plate; 16-support steel; 17-hoop body; 18-middle pier; 19-middle pier cap; 20-cap pile foundation; 21-tension screw; 22-support; 23-plug-in Buckle; 24-upper support rod; 25-assembled annular steel wall; 26-spraying device; 27-lower support rod; 28-hinged support; 29-spraying pipe; 30-new beam; 31-L-shaped jacking plate; 32-jacking device; 33-steel upright; 34-lower I-beam; 35-bridge pier corbel; 36-upper I-beam; 37-vertical tension screw; 38-new ramp bridge pier; 39-bridge pier cap; 40-bridge pier pile foundation; 41-crane; 42-insertion steel plate; 43-demolished section beam. DETAILED DESCRIPTION

[0031] The present invention is further described below in conjunction with embodiments. The description of the following embodiments is only used to help understand the present invention. It should be noted that for ordinary persons in the art, without departing from the principle of the present invention, the present invention can also be modified in some ways, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

[0032] Embodiment 1

[0033] As an example, Figures 1 to 5 As shown, the in-situ pier replacement and dismantling construction method of the steel structure overpass comprises the following steps:

[0034] S1. Set up temporary adjustable support brackets: set up temporary adjustable support brackets at both ends of the demolished section of the steel structure overpass, install limit brackets on both sides of the non-demolished section beam body 2 of the temporary adjustable support brackets, and adjust the adjustment bolts 4 on the limit brackets to make the hinged guard plate 5 abut against the non-demolished section beam body 2 to prevent the non-demolished section beam body 2 from shifting during the cutting process.

[0035] S2. Dismantle the steel structure beam within the range of the middle pier 18 of the overpass: first, install the clamp body 17 on the middle pier 18 of the overpass, and install the jack 14 on the T-shaped wing plate 15 of the clamp body 17, and use the jack 14 to symmetrically lift and assist the disengagement of the demolished section beam 43, and then cut the demolished section beam 43 within the range of the middle pier 18 according to the cutting line, and after cutting, lift it away from the site by the crane 41.

[0036] S3. Demolishing the middle pier 18 of the overpass: remove the clamp body 17 in advance, and install two sets of upper and lower assembled annular steel walls 25 on the middle pier 18, and install upper and lower support rods 27 between the plug-in buckles 23 on the assembled annular steel walls 25 and the hinged supports 28 pre-buried in the ground, and wrap a spray pipe 29 around the upper support rod 24. Then, mechanically demolish the base of the middle pier 18 and the middle pier cap 19. During the demolition process, use the spray pipe 29 to spray and reduce dust. After demolition, pre-lift the middle pier 18 with a crane 41, then release the plug-in buckle 23, and finally lift it away from the site.

[0037] S4. Construction of the new ramp bridge pier 38: construct the pier pile foundation 40, the pier cap 39 and the new ramp bridge pier 38 in sequence from bottom to top. Because the new ramp bridge pier 38 runs through the new bridge beam 30 of the overpass, pier brackets 35 are symmetrically arranged on both sides of the new ramp bridge pier 38.

[0038] S5. Hoisting of the newly built steel structure beam of the overpass: Pre-install the I-beam using the pier bracket 35, install the front and rear, upper and lower four I-beams on one side of the bracket, tension and anchor the upper and lower I-beams 34 through vertical tension screws 37, connect the front and rear I-beams through plug-in steel plates 42, then hoist the newly built beam 30 onto the support of the pier bracket 35, and simultaneously start the jacking device 32 so that the L-shaped jacking plates 31 on both sides clamp the newly built beam 30, and finally weld the newly built beam 30.

[0039] S6. Restoring the deck structure of the pedestrian bridge: After the installation of the newly built beam 30 is completed, the deck structure is constructed and the guardrail 1 structure is restored.

[0040] Embodiment 2

[0041] As another embodiment, this embodiment 2 proposes a more specific in-situ pier replacement and dismantling construction method for a steel structure overpass based on the embodiment 1:

[0042] In step S1, Figure 2 As shown, the temporary adjustable support bracket includes an integrated support base plate 12, a temporary support bracket 11, a distribution beam 9 and a limit bracket. The temporary support bracket 11 is connected to the integrated support base plate 12 by bolt anchoring. A reinforcing rod 10 is arranged between the temporary support brackets 11. A distribution beam 9 is arranged on the top of the temporary support bracket 11. Limit brackets are symmetrically arranged above both ends of the distribution beam 9, and auxiliary supports 8 are symmetrically arranged in the middle.

[0043] The limiting bracket includes a bracket upright 7 and a Y-shaped leg 3. Adjusting bolts 4 are provided on the bracket upright 7 and the Y-shaped leg 3. The end of the adjusting bolt 4 is connected to a hinged guard plate 5. The hinged guard plates 5 are connected by a hinge shaft 6. The hinged guard plate 5 is adjusted by adjusting the angle of the adjusting bolt 4 to abut against the non-removable section beam body 2. The adjusting bolt 4 on the limiting bracket is adjusted to make the hinged guard plate 5 abut against the non-removable section beam body 2 to prevent the non-removable section beam body 2 from shifting during the cutting process.

[0044] In step S2, Figure 3 As shown, T-shaped wing plates 15 are symmetrically arranged on the clamp body 17 through the supporting steel 16, and the T-shaped wing plates 15 on both sides are tensioned and anchored by tensioning screws 21. Jacks 14 are symmetrically arranged on the T-shaped wing plates 15 on both sides, and fitting blocks 13 are provided on the tops of the jacks 14 to form a clamp type micro-lifting bracket; after the demolished section beam body 43 is symmetrically lifted and assisted to be separated by the jacks 14, the demolished section beam body 43 within the range of the middle pier 18 is cut according to the cutting line, and after cutting, it is lifted away from the site by the crane 41.

[0045] In step S3, Figure 4 As shown, the clamp body 17 is removed in advance, and the assembled annular steel wall 25 is installed on the middle pier 18 in the form of a clamp, which can be divided into two or more groups, and the assembled annular steel wall 25 is provided with two layers of plug-in buckles 23 at equal intervals in the circumferential direction, and an upper support rod 24 and a lower support rod 27 are installed between the plug-in buckles 23 on the assembled annular steel wall 25 and the hinged support 28 embedded in the ground, and a spray pipe 29 can be provided on the lower support rod 27, and spray devices 26 are provided on the spray pipe 29 at equal intervals to form a pier column demolition anti-overturning dust reduction structure; the base of the middle pier 18 and the middle pier pedestal 19 are mechanically demolished, and the spray pipe 29 is used to spray dust reduction during the demolition process. After the demolition, the middle pier 18 is pre-lifted by the crane 41, and then the plug-in buckles 23 are released.

[0046] It should be noted that the parts in this embodiment that are the same or similar to those in the first embodiment can be referenced to each other and will not be described in detail in this application.

[0047] Embodiment 3

[0048] As another embodiment, this embodiment 3 proposes a more specific in-situ pier replacement and dismantling construction method for a steel structure overpass based on the first and second embodiments:

[0049] In step S5, Figure 5 and Figure 6As shown, the newly built ramp bridge pier 38 uses the pier bracket 35 to install the I-beam to form a pier bracket support. The single-side pier bracket 35 is installed with front and rear I-beams, an upper I-beam 36 and a lower I-beam 34. The upper I-beam 36 and the lower I-beam 34 are tensioned and anchored by vertical tension screws 37. The front and rear I-beams are connected by plug-in steel plates 42. The ends of the upper I-beam 36 are both provided with steel uprights 33, and a jack is provided perpendicular to the inner side of the steel uprights 33. 32, an L-shaped pushing plate 31 is connected to the end of the pushing device 32, and the L-shaped pushing plate 31 spans the front and rear I-beams to form a lateral pushing installation bracket for the steel box girder; the newly built beam body 30 is hoisted to the pier bracket support, and the pushing device 32 is opened synchronously, so that the L-shaped pushing plates 31 on both sides clamp the newly built beam body 30, and finally the newly built beam body 30 is welded; after step S5, there is also step S6: after the installation of the newly built beam body 30 is completed, the bridge deck structure is constructed, and the guardrail 1 structure is restored.

[0050] It should be noted that the parts in this embodiment that are the same or similar to those in Embodiments 1 and 2 can be referenced to each other and will not be described in detail in this application.

[0051] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

Claims

1. The in-situ pier replacement and dismantling construction method of a steel structure overpass is characterized by: The following steps are involved: S1. Set up temporary adjustable support brackets: Set up temporary adjustable support brackets at both ends of the demolished section beam body, and install limit brackets on both sides of the non-demolished section beam body of the temporary adjustable support brackets; S2. Install the hoop body on the middle pier of the overpass where the beam of the demolished section is located, and install jacks on both sides of the hoop body. Use the jacks to symmetrically lift the beam of the demolished section, cut it and lift it away; S3. Install an assembled annular steel wall on the middle pier, support it with a support rod wrapped with a spray pipe, break the middle pier and spray the spray pipe to reduce dust, and then lift it off the middle pier; S4. Construct the pier pile foundation, pier cap and new ramp bridge pier from bottom to top; S5. Install the pier bracket support on the newly built ramp bridge pier, hoist the newly built beam body to the pier bracket support, clamp it with the L-shaped push plate and then weld it; the newly built ramp bridge pier uses the pier bracket to install the I-beam to form the pier bracket support. The single-side pier bracket is installed with the front and rear I-beams, the upper I-beam and the lower I-beam. The upper I-beam and the lower I-beam are tensioned and anchored by vertical tension screws. The front and rear I-beams are connected by plug-in steel plates. The ends of the upper I-beam are all equipped with A steel column is placed, and a pusher is arranged perpendicular to the inner side of the steel column. The end of the pusher is connected to an L-shaped push plate. The L-shaped push plate spans the front and rear I-beams to form a lateral push installation bracket for the steel box girder; the newly built beam body is hoisted to the pier bracket support, and the pusher is simultaneously turned on, so that the L-shaped push plates on both sides clamp the newly built beam body, and finally the newly built beam body is welded; after step S5, there is also step S6: after the installation of the newly built beam body is completed, the bridge deck structure is constructed and the guardrail structure is restored.

2. The in-situ pier replacement and dismantling construction method for a steel structure overpass according to claim 1 is characterized in that: In step S1, the temporary adjustable support bracket includes an integrated support base plate, a temporary support bracket, a distribution beam and a limit bracket. The temporary support bracket is connected to the integrated support base plate by bolt anchoring. Reinforcing rods are arranged between the temporary support brackets. A distribution beam is arranged on the top of the temporary support bracket. Limit brackets are symmetrically arranged above both ends of the distribution beam, and auxiliary supports are symmetrically arranged in the middle.

3. The in-situ pier replacement and dismantling construction method for a steel structure overpass according to claim 1 is characterized in that: In step S1, the limiting bracket includes a bracket upright and a Y-shaped leg, and the bracket upright and the Y-shaped leg are both provided with adjusting bolts, and the end of the adjusting bolt is connected to a hinged guard plate, and the hinged guard plates are connected by a hinge shaft. The angle of the hinged guard plate is adjusted by the adjusting bolt to abut against the non-removable section beam body, and the adjusting bolt on the limiting bracket is adjusted to make the hinged guard plate abut against the non-removable section beam body to prevent the non-removable section beam body from shifting during the cutting process.

4. The in-situ pier replacement and dismantling construction method for a steel structure overpass according to claim 1 is characterized in that: In step S2, T-shaped wing plates are symmetrically arranged on the main body of the clamp through supporting steel sections, the T-shaped wing plates on both sides are tensioned and anchored by tensioning screws, jacks are symmetrically arranged on the T-shaped wing plates on both sides, and fitting blocks are provided on the tops of the jacks to form a clamp-type micro-lifting bracket; after the demolished section beam body is symmetrically lifted and assisted to be separated by the jacks, the demolished section beam body within the range of the middle pier is cut according to the cutting line, and after cutting, it is lifted away from the site by a crane.

5. The in-situ pier replacement and dismantling construction method for a steel structure overpass according to claim 1 is characterized in that: In step S3, the clamp body is removed in advance, and the assembled annular steel wall is installed on the middle pier in the form of a clamp, which is divided into two or more groups, and the assembled annular steel wall is provided with two layers of plug-in buckles at equal intervals in the circumferential direction, and an upper support rod and a lower support rod are installed between the plug-in buckles on the assembled annular steel wall and the hinged supports pre-buried in the ground, and a spray pipe is provided on the lower support rod, and spray devices are provided on the spray pipe at equal intervals to form a pier column demolition anti-overturning dust reduction structure; the middle pier base and the middle pier pedestal are mechanically removed, and the spray pipe is used to spray dust reduction during the removal process, and the middle pier is pre-lifted by a crane after the removal, and then the plug-in buckles are released.

6. The in-situ pier replacement and dismantling construction method for a steel structure overpass according to claim 1 is characterized in that: In step S4, the pier pile foundation, the pier cap and the newly built ramp bridge piers are constructed in sequence from bottom to top. The newly built ramp bridge piers run through the newly built beam body of the overpass, and pier brackets are symmetrically arranged on both sides of the newly built ramp bridge piers.

7. In-situ pier replacement and dismantling system for steel structure overpass, characterized by: Used to implement the method according to any one of claims 1 to 6.

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