Method for reinforcing old masonry arch bridge through weathering resistant steel arch

Abstract

The invention discloses a method for reinforcing an old masonry arch bridge by using weathering-resistant steel arches, which comprises the following steps of: reinforcing the bottom of a main arch bar of the old masonry arch bridge by using a plurality of weathering-resistant steel arches, and anchoring a weathering-resistant steel support in an enlarged section pier and a foundation of the main arch by using a rigid arch foot, the weathering-resistant steel arch is connected with the old masonry main arch through anchor bolts to form a combined arch ring which is jointly stressed, so that a weathering-resistant steel arch reinforcing structure of the old masonry arch bridge is realized; a pressure glue injection method is adopted for repairing cracks existing in the original arch slab, and after a high-ductility concrete layer is painted at the connecting position of the bottom of the original arch slab and the weather-resistant steel arch, pin key anchor bolts are implanted; transverse connecting profile steel is arranged between the multiple sectionally-formed weathering-resistant steel arches to form a weathering-resistant steel frame-arch structure stress system. And the weathering steel arches and the original masonry main arch plates are tightly connected and cooperatively reinforced through pin keys and high-pressure grouting. Compared with a common steel arch reinforced masonry arch bridge, the material and construction cost of anti-corrosion measures can be effectively reduced, the reinforcing construction period is shortened, and the cost and time of later anti-corrosion maintenance are saved.

Description

Technical Field

[0001] The invention relates to the field of reinforcing old masonry arch bridges, and in particular to a method for reinforcing old masonry arch bridges with weathering steel arches. Background Art

[0002] The old masonry arch bridge has been in use for a long time and has been subjected to heavy traffic loads, which has caused the aging of materials, structural cracks in the arch structure and bridge deck pavement, and surface deterioration, crystallization, and water seepage of components such as the main arch and the belly arch, resulting in a decrease in bearing capacity. In order to ensure the structural safety of the old masonry arch bridge and extend its service life, it is necessary to reinforce and renovate the old masonry arch bridge.

[0003] At present, traditional bridge reinforcement methods are mainly divided into reinforcement methods of changing the structural force transmission system and reinforcement methods of expanding the cross-section of original components using various materials.

[0004] Although the reinforcement method of changing the structural force transmission system can greatly improve the bearing capacity of the bridge, it is restricted by many existing conditions, has great construction difficulties, a long construction period and high economic costs.

[0005] Different reinforcement materials can be used for the original component expansion cross-section reinforcement method. The method of adding reinforced concrete arches directly to the bottom of the arch slab can theoretically improve the bearing capacity of the masonry arch slab, but the construction is difficult, especially the difficulty in reserving concrete formwork and support pouring ports, and it is difficult to ensure the quality of concrete pouring and vibration construction, which affects the reinforcement effect of the actual project.

[0006] Steel structures have been widely used as reinforcement materials. However, the corrosion-prone nature of ordinary steel makes this solution have problems such as high maintenance costs, short service life and environmental pollution. The corrosion of steel not only affects the structural safety of the bridge, but also requires regular anti-corrosion treatment, which increases long-term maintenance costs and poses a potential risk of pollution to the surrounding environment.

[0007] Therefore, how to improve the bearing capacity while reducing the construction economic cost, simplifying the construction reinforcement process, improving the construction progress and ensuring the quality of reinforcement construction has become a technical problem that needs to be solved urgently in this field. Summary of the invention

[0008] In view of the deficiencies of the above-mentioned prior art, the purpose of the present invention is to provide a method for reinforcing old masonry arch bridges with weathering steel arches. By utilizing the self-corrosion protection properties of weathering steel, the problems of easy corrosion, high maintenance costs and environmental pollution of ordinary steel can be compensated. While improving the overall bearing capacity of the bridge, the economic cost of construction can be reduced, the construction reinforcement process can be simplified, the construction progress can be improved and the quality of reinforcement construction can be ensured, thereby improving the structural resistance of the masonry arch bridge.

[0009] The present invention adopts the following technical solution:

[0010] A method for reinforcing an old masonry arch bridge with a weathering steel arch comprises the following steps:

[0011] Step 1: Use multiple weathering steel arches to reinforce the bottom of the main arch of the old masonry arch bridge. The weathering steel arch is connected to the main arch of the old masonry arch bridge through pin anchor bolts to form a combined arch ring to bear force together, so as to realize the weathering steel arch reinforcement structure of the old masonry arch bridge; a fixed steel support is provided at the arch foot of the weathering steel arch, and the fixed steel support is anchored in the expanded cross-section pier and foundation under the main arch of the old masonry arch bridge with high-strength weathering steel bolts;

[0012] Step 2: Use the pressure injection method to repair the cracks on the slab of the main arch of the old masonry arch bridge, and then implant pin anchor bolts after painting the bottom of the slab of the main arch of the old masonry arch bridge with a high-ductility concrete layer;

[0013] Step 3: Transverse connecting steel is arranged between multiple weathering steel arches to form a weathering steel frame arch structure force system;

[0014] Step 4: The weathering steel arch and the main arch plate of the old masonry arch bridge are tightly connected and coordinated and reinforced through pin anchor bolts and high-pressure grouting.

[0015] Preferably, the weathering steel arch is formed by welding segmented weathering steel, and the welding rods used are welding rods matching the weathering steel.

[0016] Preferably, before the pressure injection method is used to repair the cracks existing on the plate of the main arch of the old masonry arch bridge, the bottom of the plate of the main arch of the old masonry arch bridge needs to be cleaned with a high-pressure water gun.

[0017] Preferably, the thickness of the high-ductility concrete layer applied to the connection between the bottom plate of the main arch of the old masonry arch bridge and the weathering steel arch is 25 mm.

[0018] Preferably, the weather-resistant steel arch and the transverse connecting steel are connected by high-strength weather-resistant bolts.

[0019] Preferably, the weathering steel arch and transverse connecting steel are made of high-strength weathering steel; the pin anchor bolts are made of a material matching weathering steel; the fixed steel support includes a pad and a rib plate, all of which are made of weathering steel.

[0020] Beneficial effects:

[0021] (1) Compared with the existing reinforcement method of adding reinforced concrete arches to the bottom of masonry arch slabs, weathering steel arches are lightweight, high-strength, and reliable in construction quality, which can ensure the reinforcement effect of improving the overall bearing capacity of old masonry arch bridges.

[0022] (2) The installation of weather-resistant steel arches is simple and quick, with a short construction period, which greatly simplifies the reinforcement construction process and speeds up the construction progress.

[0023] (3) Multiple weathering steel arches are connected by transverse connecting steel profiles, which not only enhances the horizontal stiffness of the masonry arch bridge, but also effectively prevents the arch bridge from excessive deformation or instability. The transverse connecting steel profiles can evenly distribute the load of the structure, further improving the overall bearing capacity of the bridge.

[0024] (4) Compared with the method of reinforcing masonry arch bridges with ordinary steel arches, weathering steel is a new type of steel with self-corrosion resistance, which can effectively reduce the material and construction costs of anti-corrosion measures and save construction time.

[0025] (5) Weathering steel has self-corrosion resistance. No additional anti-corrosion treatment is required for weathering steel, which reduces the cost and time of subsequent maintenance. In an environment with alternating dry and wet conditions and severe corrosion, the performance of weathering steel is better than that of ordinary steel.

[0026] (6) Although the unit price of weathering steel is about 10% higher than that of ordinary steel, its excellent corrosion resistance and reduced maintenance costs during use make it a more cost-effective reinforcement method for old masonry arch bridges, making it a more economical and effective reinforcement method. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a logic block diagram of the construction method of the present invention;

[0028] Figure 2 It is a structural schematic diagram of the reinforced masonry arch bridge of the present invention;

[0029] Figure 3 A schematic diagram of a frame-arch structure for reinforcing the main arch section of a masonry arch bridge according to the present invention;

[0030] Figure 4 A schematic diagram of the arch foot connection structure of the reinforced masonry arch bridge according to the present invention;

[0031] Figure 5 It is a schematic diagram of the cross-section of the arch foot connection of the reinforced masonry arch bridge of the present invention;

[0032] Figure 6 The present invention is a schematic structural diagram of the main arch upper ventral arch wall of the reinforced masonry arch bridge.

[0033] Figure numerals: 1 is a weathering steel arch, 2 is the main arch of the old masonry arch bridge, 3 is high-pressure grouting, 4 is a pin anchor bolt, 5 is an expanded section pier and foundation, 6 is a high-strength weathering steel bolt, 7 is a transverse connecting steel, 8 is a pad, 9 is a rib plate, and 10 is a fixed steel support. DETAILED DESCRIPTION

[0034] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments of the present invention.

[0035] like Figure 1-6As shown: A method for reinforcing an old masonry arch bridge with a weathering steel arch, the specific steps are as follows:

[0036] Step 1: A plurality of weathering steel arches 1 are used to reinforce the bottom of the plate of the main arch 2 of the old masonry arch bridge. The weathering steel arch 1 is connected with the main arch 2 of the old masonry arch bridge through a pin anchor bolt 4 to form a combined arch ring for joint force, thereby realizing the weathering steel arch 1 reinforcement structure of the old masonry arch bridge; a fixed steel support 10 is provided at the arch foot of the weathering steel arch 1, and the fixed steel support 10 is anchored in the enlarged cross-section pier and foundation 5 under the arch bottom of the main arch 2 of the old masonry arch bridge by a high-strength weathering steel bolt 6;

[0037] Step 2: using a pressure injection method to repair cracks existing on the plate of the main arch 2 of the old masonry arch bridge, and after painting a high-ductility concrete layer on the bottom of the plate of the main arch 2 of the old masonry arch bridge, implanting a pin anchor bolt 4;

[0038] Step 3: arranging transverse connecting steels 7 between multiple weathering steel arches 1 to form a weathering steel frame arch structure force system;

[0039] Step 4: The weathering steel arch 1 and the plate of the main arch 2 of the old masonry arch bridge are tightly connected and coordinated reinforced through pin key anchor bolts 4 and high-pressure grouting 3.

[0040] The weathering steel arch 1 is formed by welding segmented weathering steel, and the welding rods used for welding are welding rods matching the weathering steel.

[0041] Before the pressure injection method is used to repair the cracks existing on the plate of the main arch 2 of the old masonry arch bridge, the bottom of the plate of the main arch 2 of the old masonry arch bridge needs to be cleaned with a high-pressure water gun.

[0042] The thickness of the high-ductility concrete layer painted on the connection part between the slab bottom of the main arch 2 of the old masonry arch bridge and the weathering steel arch 1 is 25 mm.

[0043] The weathering steel arch 1 and the transverse connecting steel 7 are connected by high-strength weathering bolts 6 .

[0044] The weathering steel arch 1 and the transverse connecting steel 7 are made of high-strength weathering steel; the pin anchor 4 is made of a material matching the weathering steel; the fixed steel support 10 includes a pad 8 and a rib 9, all of which are made of weathering steel.

[0045] In the process of weathering steel arch reinforcement of masonry arch bridge, the installation steps of weathering steel arch reinforcement of masonry arch bridge are as follows:

[0046] 1. Erect the weathering steel arch and reserve a construction gap at the arch foot;

[0047] 2. Install the jacking jack, push along the axial direction of the weathering steel arch, and load it to the design pressure;

[0048] 3. Use rigid arch foot steel supports to connect the weathering steel arch to the piers and foundation.

[0049] The above is a detailed description of the embodiments of the present invention in conjunction with the accompanying drawings, but the present invention is not limited to the described embodiments. For those skilled in the art, various changes, modifications, deformations or substitutions made within the essential scope of the present invention still belong to the protection scope of the present invention.

Claims

1. A method for reinforcing an old masonry arch bridge with a weathering steel arch, characterized in that: The following steps are involved: Step 1: Use multiple weathering steel arches to reinforce the bottom of the main arch of the old masonry arch bridge. The weathering steel arch is connected to the main arch of the old masonry arch bridge through pin anchor bolts to form a combined arch ring to bear force together, so as to realize the weathering steel arch reinforcement structure of the old masonry arch bridge; a fixed steel support is provided at the arch foot of the weathering steel arch, and the fixed steel support is anchored in the expanded cross-section pier and foundation under the main arch of the old masonry arch bridge with high-strength weathering steel bolts; Step 2: Use the pressure injection method to repair the cracks on the slab of the main arch of the old masonry arch bridge, and then implant pin anchor bolts after painting the bottom of the slab of the main arch of the old masonry arch bridge with a high-ductility concrete layer; Step 3: Transverse connecting steel is arranged between multiple weathering steel arches to form a weathering steel frame arch structure force system; Step 4: The weathering steel arch and the main arch plate of the old masonry arch bridge are tightly connected and coordinated and reinforced through pin anchor bolts and high-pressure grouting.

2. The method for reinforcing an old masonry arch bridge with a weathering steel arch according to claim 1, characterized in that: The weathering steel arch is formed by welding segmented weathering steel, and the welding rods used for welding are welding rods matching the weathering steel.

3. The method for reinforcing an old masonry arch bridge with a weathering steel arch according to claim 2, characterized in that: Before the pressure glue injection method is used to repair the cracks existing on the plate of the main arch of the old masonry arch bridge, the bottom of the plate of the main arch of the old masonry arch bridge needs to be cleaned with a high-pressure water gun.

4. The method for reinforcing an old masonry arch bridge with a weathering steel arch according to claim 3 is characterized in that: The thickness of the high-ductility concrete layer painted on the connection between the slab bottom of the main arch of the old masonry arch bridge and the weathering steel arch is 25 mm.

5. The method for reinforcing an old masonry arch bridge with a weathering steel arch according to claim 4, characterized in that: The weather-resistant steel arch and the transverse connecting steel are connected by high-strength weather-resistant bolts.

6. The method for reinforcing an old masonry arch bridge with a weathering steel arch according to claim 5, characterized in that: The weathering steel arch and transverse connecting steel are made of high-strength weathering steel; the pin anchor bolts are made of materials matching weathering steel; the fixed steel support includes a pad and a rib plate, all of which are made of weathering steel.

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