CN111778881B - Method for reinforcing arch springing section of box arch by combining fiber woven mesh reinforcement and ECC (error correction code) with single-side enlarged cross section - Google Patents
Method for reinforcing arch springing section of box arch by combining fiber woven mesh reinforcement and ECC (error correction code) with single-side enlarged cross section Download PDFInfo
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- E—FIXED CONSTRUCTIONS
- E01—CONSTRUCTION OF ROADS, RAILWAYS, OR BRIDGES
- E01D—CONSTRUCTION OF BRIDGES, ELEVATED ROADWAYS OR VIADUCTS; ASSEMBLY OF BRIDGES
- E01D22/00—Methods or apparatus for repairing or strengthening existing bridges ; Methods or apparatus for dismantling bridges
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- E—FIXED CONSTRUCTIONS
- E01—CONSTRUCTION OF ROADS, RAILWAYS, OR BRIDGES
- E01D—CONSTRUCTION OF BRIDGES, ELEVATED ROADWAYS OR VIADUCTS; ASSEMBLY OF BRIDGES
- E01D4/00—Arch-type bridges
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- Y02A30/30—Adapting or protecting infrastructure or their operation in transportation, e.g. on roads, waterways or railways
Abstract
The invention discloses a method for reinforcing an arch springing section of a box arch by combining fiber woven mesh reinforcement and ECC (error correction code) with single-side increased cross section, which mainly uses arch back reinforced concrete, fiber woven mesh and ECC material, wherein the arch back reinforced concrete not only obviously improves the bearing capacity of a structure, but also has a weight function; the fiber woven mesh can meet the requirements of different tensile strengths by increasing or reducing the yarn number and weaving the fiber meshes with different cross-sectional areas; the fiber mixing amount of the ECC material is not more than 2.5 percent of the total volume, the ultimate tensile strain of the ECC material is stably more than 1 percent, the ECC material has obvious strain hardening characteristics, and the crack development on the surface of the structure is effectively inhibited. The method is simple in field operation, can effectively improve the bearing capacity of the structure, solves the problem of cooperative stress of the reinforcing layer and the original structure to the maximum extent, can enhance the integrity of the reinforcing structure, and can also obviously improve the durability of the structure.
Description
Technical Field
The invention relates to the technical field of bridge maintenance and reinforcement, in particular to a method for reinforcing an arch springing section of a box arch by combining fiber woven mesh reinforcement and ECC (error correction code) with single-side increased cross section.
Background
Since the 80 s of the last century, a large number of reinforced concrete arch bridges are built in China, particularly in the southwest region. With the rapid development of construction technology and the development of large-scale hoisting equipment and instruments, the reinforced concrete box-type arch bridge gradually becomes the dominant bridge type of the concrete arch bridge. The main arch ring is used as a main bearing component of the arch bridge, and under the action of constant load and live load, besides the pressure in the arch axis direction, a large negative bending moment can be generated at the arch foot position. Along with the increase of the operation life of the bridge, the material performance is deteriorated due to the influence of various actions such as vehicle overload, overrun and environmental factors, the structural strength is reduced, the phenomena such as cracks and damages are generated at the tension area of the main arch ring, and the structural bearing capacity is reduced. Therefore, the box-type arch bridge arch foot section becomes a key part influencing the bearing capacity and the durability of the whole structure, and the maintenance and reinforcement method selection of the key part is crucial.
According to the design specification for reinforcing highway bridges (JTG/T J22-2008) and the design specification for reinforcing concrete structures (GB 50367 and 2013), the conventional technical approaches for repairing and reinforcing arch bridges are as follows: the section enlarging method (including reinforced concrete hoop reinforcement), the steel plate (section steel) adhering reinforcement method, the fiber composite adhering reinforcement method and the pre-tensioned steel wire rope (steel strand) mesh-polymer mortar surface layer reinforcement method respectively have advantages and disadvantages, and are detailed in table 1.
TABLE 1 common strengthening method for arch bridge
In the work of bridge detection and reinforcement, the applicant encounters the examples that the existing reinforcement method for the arch bridge is difficult to achieve the expected target, and typically, two reinforced concrete box arch bridges are provided, wherein the former adopts a method of reinforcing an arch foot section by using a reinforced concrete hoop, and the latter adopts a reinforcement method of adhering a steel plate to an arch belly. However, through cracks are detected to appear between the hoop reinforcing layer and the original structure along the joint surface within 3 months after the first bridge is reinforced. After the latter bridge is reinforced for 5 years, the void ratio of the steel plates reaches 32% of the total number of the spot checks, and 10 steel plates are completely void. The two bridge reinforcing cases are examples and show common problems, and in the feedback of the reinforcing effect of the management and maintenance unit, the applicant finds that a better scheme is not available at present for reinforcing the arch bridge, particularly for reinforcing the arch leg section of the box-type arch bridge, so that a novel reinforcing technology needs to be developed.
Disclosure of Invention
In view of the above, there is a need for a fiber-woven mesh reinforced ECC combined with a single-side enlarged cross-section reinforced box arch leg, which can inhibit the propagation of cracks on the surface of the arch leg, reduce the surface defects of the structure, and improve the bearing capacity of the arch bridge and the integrity and durability of the arch leg.
In order to achieve the purpose, the technical scheme adopted by the invention is as follows:
a method for reinforcing a box arch springing section by combining fiber woven mesh reinforcement and ECC (error correction code) with single-side enlarged cross section comprises the following steps:
1) determining a reinforced area according to the defect condition of the arch leg of the box arch;
2) concrete surface treatment of the reinforced area: firstly, removing degraded concrete such as concrete surface peeling, loosening, sanding, weathering, honeycombing, corrosion and the like, performing chiseling treatment, adopting high-pressure water washing after an aggregate new surface is exposed, performing grouting treatment on cracks with the width of more than 0.15mm, wherein the surface roughness of the aggregate new surface is not less than 6 mm;
3) determining the position of the steel bar of the arch rib by using a steel bar detector, and then performing steel bar planting hole position lofting, drilling and hole cleaning treatment on the arch back to ensure the accuracy of the hole position and the effective depth of the drilling, wherein the operation avoids the main steel bar of the original structure;
4) planting bars, determining the anchoring depth strictly according to the design requirements, and selecting proper structural adhesive through a field drawing test;
5) installing a template and binding a reinforcing mesh on the arch back of the reinforced area;
6) pouring to form an arch back reinforced concrete layer: carrying out arch back reinforcing concrete pouring at the arch backs of the arch springing sections, wherein the reinforcing concrete adopts a construction process of sectional cast-in-place, and carrying out galling treatment on the surface of the concrete after pouring is finished;
7) after the strength of the arch back reinforced concrete reaches 95% of the design strength, spraying a structural interface agent for concrete on the surface of the reinforced area, uniformly pressing and smearing the prepared bottom ECC material on the surface of the reinforced area, and chamfering edges and corners around the arch leg section in the pressing and smearing process, wherein the radius of the chamfer is not less than 25 mm;
8) cutting the fiber woven mesh by comprehensively considering the area of the reinforcing area and construction convenience conditions, and carrying out viscose sand hanging treatment after the fiber woven mesh is cut;
9) laying a fiber woven net along the arch ring direction of the box, tensioning the fiber woven net, laying and fixing U-shaped nails at proper intervals, wherein the fiber woven net is annularly lapped and positioned at the center of the arch back, the lapping length is not less than 20cm, the lapping length of the fiber woven net along the longitudinal direction of the arch ring is not less than 10cm, and the lapping part is bonded and fixed by using epoxy resin;
10) uniformly pressing and smearing the prepared top ECC material on the surface of the arch springing section, smoothing and leveling to ensure compactness and flatness, wherein the pressing and smearing time interval of the top ECC material is subject to initial setting of the bottom ECC material;
11) and (3) performing water spraying maintenance on the construction surface within 0.5-4 hours after the ECC material is pressed and smeared, wherein the maintenance time is not less than 7 days, and the reinforced part is prevented from being impacted by hard objects during the maintenance time.
Preferably, in step 9), the number of layers of the woven fiber mesh can be adjusted according to actual conditions, when multiple layers are laid, the thickness of the interlayer ECC material is not less than the thickness of a protective layer formed by the woven fiber mesh and not more than 10mm, pressing and smearing construction of the interlayer ECC material needs to be performed after the previous layer of ECC material is initially set, and after pressing and smearing construction of the interlayer ECC material is completed, a wood trowel needs to be used for repeatedly rubbing hair on the surface of the slurry along the longitudinal and transverse directions.
Preferably, the fiber woven mesh adopts a unidirectional grid, the annular direction adopts a fiber material with high tensile strength, and the longitudinal fiber of the arch ring mainly plays a fixing role.
Preferably, the thickness of the bottom layer ECC material is not less than the thickness of the protective layer formed by the fiber woven mesh and not more than 20 mm.
Preferably, the ECC material is designed by taking cement or cement and filler or small-particle-size fine aggregate as a matrix and short fiber as a reinforcing material, wherein the fiber content does not exceed 2.5 percent of the total volume of the ECC material, and the ultimate tensile strain of the ECC material is stabilized to be more than 1 percent.
Compared with the prior art, the invention has the following beneficial effects:
the invention fully utilizes the high-strength characteristic of the fiber woven net, increases the section area of the member and improves the rigidity and the bearing capacity of the structure;
secondly, the construction process of pouring the reinforced concrete of the arch backs of the arch springing sections is mature, the fiber woven mesh is convenient and quick to lay, ECC materials only need to be pressed and smeared, and heavy templates and supporting systems are not needed, so that the field construction operation is simple, the speed is high, and the safety risk is low;
the arch back reinforcing concrete pouring of the arch springing section not only obviously improves the bearing capacity of the structure, but also has the function of weight;
the adopted cement-based material with ultrahigh toughness has very high ultimate tensile strain and obvious strain hardening characteristic, and can generate a plurality of fine cracks under the action of tensile stress, which are favorable for inhibiting the crack development at the arch springing section; even if cracks are generated, the speed of harmful media such as water or carbon dioxide entering the structure can be obviously reduced due to the control of the width of the cracks;
the fiber woven mesh is adopted as a stress material, so that the ductility of the structure can be effectively improved, and the material has the characteristics of ageing resistance, fatigue resistance and corrosion resistance, so that no special requirement is imposed on the thickness of a protective layer;
the fiber woven mesh can meet the requirements of different tensile strengths by increasing or reducing the number of yarns and weaving meshes with different cross sections, and has strong designability; in addition, the fiber material has soft texture and strong construction operability;
sixthly, the fiber woven mesh reinforced ECC has a hoop effect, and prevents the extrados reinforced concrete from generating interface through seams with an original structure;
the fiber woven mesh reinforced ECC reinforcing layer has good chemical stability and durability, the structural integrity can be reinforced, and the structural durability can be obviously improved.
Drawings
FIG. 1 is a schematic view of a method for reinforcing arch springing of a box arch by combining fiber woven mesh reinforcement ECC with single-sided increased cross section reinforcement of the invention.
Fig. 2 is a schematic view of a partial structure of a arch leg segment in cm.
Fig. 3 is a graph of the arch ring reinforcement of the reinforced area of fig. 2, in cm.
FIG. 4 is a schematic diagram of the structure of the large sample A in FIG. 3, in cm.
Figure 5 is a detail view of a woven fibre mesh in cm.
Fig. 6 is a schematic illustration of reinforcement.
Description of the main elements
In the figure: the box arch comprises a box arch foot section 1, arch back reinforced concrete 2, a bottom layer ECC material 3, a fiber woven mesh 4 and a top layer ECC material 5.
The following detailed description will further illustrate the invention in conjunction with the above-described figures.
Detailed Description
Referring to fig. 1, in a preferred embodiment of the present invention, a method for reinforcing ECC with a woven fiber mesh combined with a single-sided reinforced box arch springing comprises the following steps:
1) and determining a reinforcement area according to the defect condition of the arch leg section 1 of the box arch, thereby making a preliminary reinforcement scheme.
2) Concrete surface treatment of the reinforced area: firstly, removing degraded concrete such as concrete surface peeling, loosening, sanding, weathering, honeycombing, corrosion and the like, roughening, exposing a new aggregate surface, washing with high-pressure water, performing grouting treatment on cracks with the width of more than 0.15mm, wherein the surface roughness of the new aggregate surface is not less than 6 mm.
3) The reinforcing steel bar detector is utilized to determine the position of the reinforcing steel bars of the arch rib, and then the steel bar planting hole site lofting, drilling and hole cleaning treatment are carried out on the arch back, so that the accuracy of the hole site and the effective depth of the drilling are ensured, and the operation avoids the main reinforcing steel bars of the original structure.
4) And (4) planting the steel bars, determining the anchoring depth strictly according to the design requirement, and selecting proper structural adhesive through a field drawing test.
5) And (5) carrying out template installation and reinforcement mesh binding on the arch backs in the reinforcement areas.
6) Pouring to form an arch back reinforced concrete layer 2: and (3) pouring the arch back reinforcing concrete at the arch back of the arch foot section 1, wherein the reinforcing concrete adopts a construction process of sectional cast-in-place, and roughening treatment is carried out on the surface of the concrete after pouring is finished so as to reduce the contraction or hydration heat influence of the concrete.
7) After the strength of the arch back reinforced concrete reaches 95% of the design strength, spraying a structural interface agent for concrete on the surface of the reinforced area, uniformly pressing and smearing the prepared bottom ECC material 3 on the surface of the reinforced area, and chamfering edges and corners around the arch leg section 1 in the pressing and smearing process, wherein the chamfering radius is not less than 25 mm.
8) The area of the reinforcing area and the construction convenience condition are comprehensively considered, the fiber woven mesh 4 is cut, and after the fiber woven mesh 4 is cut, the viscose is subjected to sand hanging treatment.
9) Along case arch ring to laying fibre woven mesh 4, taut fibre woven mesh 4, fixed U type nail is laid to suitable interval, and 4 hoop overlap joints of fibre woven mesh are located the hunch back center, and overlap joint length is not less than 20cm, and fibre woven mesh 4 is not less than 10cm along the fore-and-aft overlap joint length of hunch circle, and the overlap joint position uses epoxy to bond fixedly. In the present invention, the thickness of the bottom layer ECC material 3 is not less than the thickness of the protective layer formed by the fiber woven mesh 4 and not more than 20 mm. Furthermore, the number of layers laid by the fiber woven mesh 4 can be adjusted according to actual conditions, when the fiber woven mesh is laid in multiple layers, the thickness of the interlayer ECC material is not less than that of a protective layer formed by the fiber woven mesh 4 and is not more than 10mm, the pressing and smearing construction of the interlayer ECC material needs to be carried out after the previous layer of ECC material is initially set, and after the pressing and smearing construction of the interlayer ECC material is completed, a wood trowel needs to be used for repeatedly rubbing hair on the surface of slurry in the longitudinal and transverse directions. The fiber woven mesh 4 is made of unidirectional meshes, the annular direction is made of fiber materials with high tensile strength, and the longitudinal fibers of the arch ring mainly play a role in fixing.
It should be noted that the fiber woven mesh 4 can be woven by increasing or decreasing the number of yarns to form meshes with different cross-sectional areas, and the mesh is selected reasonably according to the actual situation of the reinforcing structure.
10) Uniformly pressing and smearing the prepared top ECC material 5 on the surface of the arch leg section 1, smoothing and leveling to ensure compactness and flatness, wherein the pressing and smearing time interval of the top ECC material 5 is based on the initial setting of the bottom ECC material 3.
11) And (3) performing water spraying maintenance on the construction surface within 0.5-4 hours after the ECC material is pressed and smeared, wherein the maintenance time is not less than 7 days, and the reinforced part is prevented from being impacted by hard objects during the maintenance time.
In the invention, no matter the bottom ECC material 3, the top ECC material 5 or the interlayer ECC material, the ECC material (ultra-high toughness cement-based material) is adopted, the ECC material is designed by taking cement or cement plus filler or small-particle-size fine aggregate as a matrix and short fiber as a reinforcing material, wherein the fiber doping amount is not more than 2.5 percent of the total volume of the ECC material, and the ultimate tensile strain of the ECC material is stabilized to be more than 1 percent.
Aiming at the method, the applicant applies the method in the actual bridge, and the method specifically comprises the following steps:
the concrete box-shaped arch bridge in Guangxi spans the west river and is built in 1992. The upper structure of the bridge adopts an 8 multiplied by 96m reinforced concrete box arch, the net span is 96m, the net rise is 12m, the net rise ratio is 1/8, and the arch axis coefficient m is 1.543. The pier in the substructure is a concrete cantilever pier, the 0# and 8# bridge abutments are gravity type stone slab masonry bridge abutments, the 0# abutment is an open-cut enlarged foundation, the 8# abutment is an open caisson foundation, the 1# and 3# piers are assembled caisson foundations, the 2# pier is a floating steel caisson foundation, and the 4# to 7# piers are drilling cast-in-place pile foundations. The bridge deck is paved by C50 concrete.
The bridge has the main technical standards that:
1. full width of the bridge deck: 13.90m ═ 0.50m (sidewalk guardrail) +1.70m (sidewalk) +0.25m (lane guardrail) +9.00m (lane clear width) +0.25m (lane guardrail) +1.70m (sidewalk) +0.50m (sidewalk guardrail);
2. design load rating (after 2014 reinforcement): Highway-II, population 3.5kN/m2(JTG D60-2004);
3. bridge floor cross slope: bidirectional 1.5%.
In 7 months in 2019, the bridge is designed to be reinforced according to the current traffic volume condition, and the automobile load grade is improved to a highway-I grade. The applicant team follows basic principles of safety and applicability, reliable technology, durability and economy and reasonability to adopt the technology of combining fiber woven mesh 4 reinforced ECC with single-side enlarged cross section reinforced concrete box arch leg sections 1 in the three small span ranges of the bridge box arch leg sections 1 and uses the technology as a selection scheme.
The reinforcement design drawings are shown in detail in fig. 2-6, and the concrete implementation steps of the reinforcement method are as follows:
1) and determining a reinforcement area according to the defect condition of the arch leg section 1 of the box arch, thereby making a preliminary reinforcement scheme.
2) Concrete surface treatment of the reinforced area: firstly, removing degraded concrete such as concrete surface peeling, loosening, sanding, weathering, honeycombing, corrosion and the like, roughening, exposing a new aggregate surface, washing with high-pressure water, performing grouting treatment on cracks with the width of more than 0.15mm, wherein the surface roughness of the new aggregate surface is not less than 6 mm.
3) The reinforcing steel bar detector is utilized to determine the position of the reinforcing steel bars of the arch rib, and then the steel bar planting hole site lofting, drilling and hole cleaning treatment are carried out on the arch back, so that the accuracy of the hole site and the effective depth of the drilling are ensured, and the operation avoids the main reinforcing steel bars of the original structure. During specific operation, the diameter of a drill hole is 16mm, the arch rib is implanted for 15cm, bar-planting glue is poured into the drill hole, and the construction process and the material property of the bar-planting glue meet the requirements of relevant specifications.
4) And (4) planting the steel bars, determining the anchoring depth strictly according to the design requirement, and selecting proper structural adhesive through a field drawing test.
5) And (5) carrying out template installation and reinforcement mesh binding on the arch backs in the reinforcement areas.
6) Pouring to form an arch back reinforced concrete layer 2: and (3) pouring the arch back reinforcing concrete at the arch back of the arch springing section 1, wherein the pouring thickness is 30cm, the reinforcing concrete adopts a construction process of sectional cast-in-place, and roughening treatment is carried out on the surface of the concrete after pouring is finished so as to reduce the contraction or hydration heat influence of the concrete.
7) After the strength of the arch back reinforced concrete reaches 95% of the design strength, spraying a structural interface agent for concrete on the surface of the reinforced area, uniformly pressing and smearing the prepared bottom layer ECC material 3 on the surface of the reinforced area, wherein the thickness of the bottom layer ECC material 3 is 10mm, chamfering the edges and corners around the arch foot section 1 in the pressing and smearing process, and the chamfering radius is 35 mm.
The ECC material 3 at the bottom layer is an ECC material (ultra-high-toughness cement-based material) which is designed by taking cement or cement with filler or small-particle-size fine aggregate as a matrix and short fiber as a reinforcing material, wherein the fiber doping amount does not exceed 2.5 percent of the total volume of the ECC material, the hardened composite material has obvious strain hardening characteristics, a plurality of fine cracks can be generated under the action of tensile load, and the ultimate tensile strain is stabilized to be more than 1 percent. The performance indexes of the internally doped short fibers are shown in a table 2.
TABLE 2 ultra high tenacity Cement-based materials incorporating short fiber performance index
| Length (mm) | Diameter (μm) | Tensile strength (Mpa) | Elongation (%) | Tensile modulus of elasticity (GPa) | Density (g/cm)3) |
| 12 | 39 | 1620 | 7 | 42.8 | 1.3 |
8) The area of the reinforcing area and the construction convenience condition are comprehensively considered, the fiber woven mesh 4 is cut, and after the fiber woven mesh 4 is cut, the viscose is subjected to sand hanging treatment. In the present embodiment, the fiber mesh grid 4 is formed by weaving mutually perpendicular carbon fiber wires/glass fiber wires, wherein the stressed direction adopts carbon fiber wires, and the unstressed direction adopts glass fiber wires; the width of the carbon fiber filaments in the stress direction is 3mm, and the distance between the carbon fiber filaments is 20 mm; the width of the glass fiber yarns in the non-stress direction is 2mm, and the distance between the glass fiber yarns is 20 mm; the design tensile strength of the carbon fiber in the stress direction is 1600 MPa.
9) Along case arch ring to laying fibre woven mesh 4, taut fibre woven mesh 4 adopts 20 cm's interval quincunx to arrange fixed U type nail, and 4 hoop overlap joints of fibre woven mesh are located hunch back center, and overlap joint length is not less than 20cm, and fibre woven mesh 4 is not less than 10cm along the fore-and-aft overlap joint length of hunch circle, and the overlap joint position uses epoxy to bond fixedly.
It should be noted that the fiber woven mesh 4 can be woven by increasing or decreasing the number of yarns to form meshes with different cross-sectional areas, and the mesh is selected reasonably according to the actual situation of the reinforcing structure.
10) The prepared top layer ECC material 5 is uniformly pressed on the surface of the arch leg section 1, the surface is smoothed and leveled, the compactness and the flatness are ensured, the pressing time interval of the top layer ECC material 5 is based on the initial setting of the bottom layer ECC material 3, and in the embodiment, the pressing thickness of the top layer ECC material 5 is 15 mm.
11) And (3) carrying out water spraying maintenance on the construction surface within 0.5-4 hours after the ECC material is pressed and smeared, wherein the maintenance time is 14 days, and the reinforced part is prevented from being impacted by hard objects in the period. .
The above description is intended to describe in detail the preferred embodiments of the present invention, but the embodiments are not intended to limit the scope of the claims of the present invention, and all equivalent changes and modifications made within the technical spirit of the present invention should fall within the scope of the claims of the present invention.
Claims (3)
1. A method for reinforcing a box arch springing section by combining fiber woven mesh reinforcement and ECC (error correction code) with single-side enlarged cross section is characterized by comprising the following steps:
1) determining a reinforced area according to the defect condition of the arch leg of the box arch;
2) concrete surface treatment of the reinforced area: firstly, removing concrete with surface peeling, loosening, sanding, weathering, honeycombing and corrosion deterioration, roughening, exposing a new aggregate surface, washing with high-pressure water, performing grouting treatment on cracks with the width of more than 0.15mm, and then performing high-pressure water washing on the exposed new aggregate surface;
3) determining the position of the steel bar of the arch rib by using a steel bar detector, and then performing steel bar planting hole position lofting, drilling and hole cleaning treatment on the arch back to ensure the accuracy of the hole position and the effective depth of the drilling, wherein the operation avoids the main steel bar of the original structure;
4) planting bars, determining the anchoring depth strictly according to the design requirements, and selecting proper structural adhesive through a field drawing test;
5) installing a template and binding a reinforcing mesh on the arch back of the reinforced area;
6) pouring to form an arch back reinforced concrete layer: carrying out arch back reinforcing concrete pouring at the arch backs of the arch springing sections, wherein the reinforcing concrete adopts a construction process of sectional cast-in-place, and carrying out galling treatment on the surface of the concrete after pouring is finished;
7) after the strength of the arch back reinforced concrete reaches 95% of the design strength, spraying a structural interface agent for concrete on the surface of the reinforced area, uniformly pressing and smearing the prepared bottom ECC material on the surface of the reinforced area, and chamfering edges and corners around the arch leg section in the pressing and smearing process, wherein the radius of the chamfer is not less than 25 mm;
8) cutting the fiber woven mesh by comprehensively considering the area of the reinforcing area and construction convenience conditions, and carrying out viscose sand hanging treatment after the fiber woven mesh is cut; the fiber woven mesh adopts a unidirectional grid, the annular direction adopts a fiber material with high tensile strength, and the longitudinal fiber of the arch ring mainly plays a role in fixing;
9) laying a fiber woven net along the arch ring direction of the box, tensioning the fiber woven net, laying and fixing U-shaped nails at proper intervals, wherein the fiber woven net is annularly lapped and positioned at the center of the arch back, the lapping length is not less than 20cm, the lapping length of the fiber woven net along the longitudinal direction of the arch ring is not less than 10cm, and the lapping part is bonded and fixed by using epoxy resin; the number of the layers of the fiber woven mesh can be adjusted according to actual conditions, when the fiber woven mesh is laid in multiple layers, the thickness of the interlayer ECC material is not less than that of a protective layer formed by the fiber woven mesh and not more than 10mm, the pressing and smearing construction of the interlayer ECC material needs to be carried out after the previous layer of ECC material is initially set, and after the pressing and smearing construction of the interlayer ECC material is finished, a wood trowel needs to be used for repeatedly rubbing hair on the surface of slurry along the longitudinal and transverse directions;
10) uniformly pressing and smearing the prepared top ECC material on the surface of the arch springing section, smoothing and leveling to ensure compactness and flatness, wherein the pressing and smearing time interval of the top ECC material is subject to initial setting of the bottom ECC material;
11) and (3) performing water spraying maintenance on the construction surface within 0.5-4 hours after the ECC material is pressed and smeared, wherein the maintenance time is not less than 7 days, and the reinforced part is prevented from being impacted by hard objects during the maintenance time.
2. The method of claim 1 for reinforcing a box arch springing section by combining woven fiber mesh reinforcement and ECC with single-sided increased cross-section reinforcement, wherein: the thickness of the bottom ECC material pressed is not less than that of the protective layer formed by the fiber woven net and not more than 20 mm.
3. The method of claim 1 for reinforcing a box arch springing section by combining woven fiber mesh reinforcement and ECC with single-sided increased cross-section reinforcement, wherein: the ECC material is designed by taking cement or cement and filler or small-particle-size fine aggregate as a matrix and short fiber as a reinforcing material, wherein the fiber content does not exceed 2.5 percent of the total volume of the ECC material, and the ultimate tensile strain of the ECC material is stabilized to be more than 1 percent.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH083937A (en) * | 1994-06-09 | 1996-01-09 | Kajima Corp | Repair method for existing bridge |
| CN106958208A (en) * | 2017-03-07 | 2017-07-18 | 武汉理工大学 | A kind of novel reinforced method of double curvature arched bridge |
| CN107304634A (en) * | 2016-04-19 | 2017-10-31 | 郑州大学 | A kind of high strength stainless steel silk screen strengthens ECC reinforced concrete structures |
| CN108298904A (en) * | 2018-02-08 | 2018-07-20 | 中国矿业大学 | A kind of reinforcement means for the ECC composite fibre mesh grids improving masonry wall anti-seismic performance |
| CN108867410A (en) * | 2018-07-18 | 2018-11-23 | 重庆交通大学 | The ribbed arch bridge ruggedized construction and method combined based on UHPC and presstressed reinforcing steel |
-
2020
- 2020-08-10 CN CN202010804009.3A patent/CN111778881B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH083937A (en) * | 1994-06-09 | 1996-01-09 | Kajima Corp | Repair method for existing bridge |
| CN107304634A (en) * | 2016-04-19 | 2017-10-31 | 郑州大学 | A kind of high strength stainless steel silk screen strengthens ECC reinforced concrete structures |
| CN106958208A (en) * | 2017-03-07 | 2017-07-18 | 武汉理工大学 | A kind of novel reinforced method of double curvature arched bridge |
| CN108298904A (en) * | 2018-02-08 | 2018-07-20 | 中国矿业大学 | A kind of reinforcement means for the ECC composite fibre mesh grids improving masonry wall anti-seismic performance |
| CN108867410A (en) * | 2018-07-18 | 2018-11-23 | 重庆交通大学 | The ribbed arch bridge ruggedized construction and method combined based on UHPC and presstressed reinforcing steel |
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