Precast High-Strength Stainless Steel Wire Mesh Reinforced ECC Components for Strengthening RC Columns and Construction Methods

Abstract

The present invention relates to the field of civil engineering technology, and specifically relates to a precast high-strength stainless steel wire mesh reinforced ECC member for strengthening RC columns and a construction method. The member includes a precast high-strength stainless steel wire mesh reinforced ECC plate assembly, which includes a precast prestressed high-strength stainless steel wire mesh reinforced ECC plate and a precast reserved hole ECC plate. High-strength stainless steel wire meshes are fixed in the precast prestressed high-strength stainless steel wire mesh reinforced ECC plate. Transverse steel strands are connected to the precast reserved hole ECC plate. The longitudinal direction of the high-strength stainless steel wire meshes is connected with an anchor fixing device, and both the transverse and longitudinal directions are connected with pre-tightening devices; an ECC post-cast strip is used to fill the joint after the installation of the precast high-strength stainless steel wire mesh reinforced ECC plate assembly to counteract the residual stress; an ECC plate fixing device is used to fix the precast high-strength stainless steel wire mesh reinforced ECC plate assembly circumferentially on the RC column; the present invention effectively solves the technical problem of the cumbersome process when high-strength stainless steel wire mesh reinforced ECC is used to strengthen RC columns in the prior art.

Description

Technical Field

[0001] The present invention relates to the field of civil engineering technology, and particularly relates to a precast high-strength stainless steel wire mesh reinforced ECC member for strengthening RC columns and a construction method thereof. Background Art

[0002] An RC column, that is, a reinforced concrete column, is a column made of reinforced concrete material. It is the most basic load-bearing member in various engineering structures such as houses, bridges, and hydraulic engineering, and is commonly used as the pillar of a floor slab, a bridge pier, a foundation column, a strut of a tower and a truss. At present, the most common materials used for strengthening RC columns are steel materials (prestressed steel wires, prestressed steel strands and prestressed steel plate hoops) and fiber reinforced composites (FRP). However, steel materials are prone to corrosion and have poor durability. FRP needs to be pasted on the surface of the member with epoxy resin as an adhesive, and there is a risk of falling off.

[0003] High-strength stainless steel wire mesh reinforced ECC (engineered cementitious composite) as a new type of composite material organically combines the advantages of high-strength steel wire mesh and ECC. It has high tensile strength, deformation ability, and more excellent crack dispersion and control ability. Existing research shows that the load-bearing capacity, ductility and toughness of components such as beams and columns strengthened with high-strength stainless steel wire mesh / ECC can be significantly improved under common working conditions. However, compared with the reinforcement processes with relatively simple construction techniques such as FRP wrapping and steel plate pasting, the relatively cumbersome construction process of high-strength stainless steel wire mesh reinforced ECC when used to strengthen RC columns affects its application in actual projects. Summary of the Invention

[0004] The present invention provides a precast high-strength stainless steel wire mesh reinforced ECC member for strengthening RC columns to solve the technical problem of the cumbersome process when high-strength stainless steel wire mesh reinforced ECC is used to strengthen RC columns in the prior art; the object of the present invention is also to provide a construction method of a precast high-strength stainless steel wire mesh reinforced ECC member for strengthening RC columns.

[0005] To solve the above problems, the precast high-strength stainless steel wire mesh reinforced ECC member for strengthening RC columns provided by the present invention adopts the following technical solutions:

[0006] The precast high-strength stainless steel wire mesh reinforced ECC member for strengthening RC columns includes:

[0007] Prefabricated high-strength stainless steel wire mesh reinforced ECC plate assembly, which includes a prefabricated prestressed high-strength stainless steel wire mesh reinforced ECC plate and a prefabricated reserved-hole ECC plate arranged circumferentially around the RC column. In the prefabricated prestressed high-strength stainless steel wire mesh reinforced ECC plate, there is a high-strength stainless steel wire mesh fixed by tying multiple transverse steel wires and longitudinal steel wires. The prefabricated reserved-hole ECC plate is connected to the transverse steel wires. The longitudinal direction of the high-strength stainless steel wire mesh is connected with an anchor fixing device, and both the transverse and longitudinal directions are connected with a pre-tightening device;

[0008] ECC post-cast strip, which is used to fill the joint after the installation of the prefabricated high-strength stainless steel wire mesh reinforced ECC plate assembly to counteract the residual stress;

[0009] ECC plate fixing device, which is used to fix the prefabricated high-strength stainless steel wire mesh reinforced ECC plate assembly circumferentially around the RC column.

[0010] Furthermore, the high-strength stainless steel wire mesh is arranged in the middle of the prefabricated prestressed high-strength stainless steel wire mesh reinforced ECC plate in the thickness direction, and the transverse steel wires are arranged outside the longitudinal steel wires.

[0011] Furthermore, the RC column is of rectangular structure, and the number of prefabricated reserved-hole ECC plates on the rectangular surface of the prefabricated reserved-hole ECC plate is two, and the high-strength stainless steel wire mesh is located between the two prefabricated reserved-hole ECC plates.

[0012] Furthermore, both ends of the multiple transverse steel wires in the prefabricated prestressed high-strength stainless steel wire mesh reinforced ECC plate are respectively connected and fixed to the prefabricated reserved-hole ECC plates adjacent to both sides of the prefabricated prestressed high-strength stainless steel wire mesh reinforced ECC plate.

[0013] Furthermore, when the prefabricated prestressed high-strength stainless steel wire mesh reinforced ECC plate and the prefabricated reserved-hole ECC plate are cast, PVC pipes are embedded inside them, and reserved holes are formed in the PVC pipes to respectively provide spaces for installing the high-strength stainless steel wire mesh in the prefabricated prestressed high-strength stainless steel wire mesh reinforced ECC plate and for the prefabricated reserved-hole ECC plate to connect the transverse steel wires.

[0014] Furthermore, the ECC plate fixing device includes steel-bonding glue used for smearing on the edges of the prefabricated prestressed high-strength stainless steel wire mesh reinforced ECC plate and the prefabricated reserved-hole ECC plate, and micro-expansion high-strength grouting material is poured above the inner sides of the prefabricated prestressed high-strength stainless steel wire mesh reinforced ECC plate and the prefabricated reserved-hole ECC plate after the steel-bonding glue is cured.

[0015] Further, the anchor fixing device includes a planted bar anchoring structure, and the planted bar anchoring structure includes planted bar holes and planted bar glue provided at the root of the RC column; the pre-tightening device includes an angle iron with holes, an expansion bolt, steel bonding glue, a fish-eye screw and a matching nut, and an aluminum buckle. One end of the longitudinal steel bar wire in the precast prestressed high-strength stainless steel wire mesh reinforced ECC plate is implanted into the root of the RC column, and the other end is used to install and fix the angle iron with holes by using the expansion bolt and the steel bonding glue. The aluminum buckle is used to connect to the fish-eye screw fixed on the angle iron with holes after the steel bonding glue and the planted bar glue in the planted bar holes are cured.

[0016] Further, the planted bar holes are inclined 20°-30° toward the RC column side.

[0017] Further, it also includes a simple formwork surrounding the outer periphery of the precast prestressed high-strength stainless steel wire mesh reinforced ECC plate and the precast reserved hole duct ECC plate.

[0018] The beneficial effects of the precast high-strength stainless steel wire mesh reinforced ECC member for strengthening RC columns provided by the present invention are as follows: By prefabricating the high-strength stainless steel wire mesh reinforced ECC main body into a plate and cooperating with the post-cast strip for strengthening, the construction process is greatly simplified, the construction period is accelerated, and the labor demand is small. At the same time, since the cross-sectional area of the post-cast strip is small, the influence of the climate can be not considered. The combined use of steel bonding glue, slightly expanding grouting material, and the pre-tightening device for steel strands in all directions ensures the effective bonding between the high-strength stainless steel wire mesh reinforced ECC main body plate and the base surface, and prestress is applied in all directions, further enabling the excellent performance of the high-strength stainless steel wire mesh reinforced ECC to be fully exerted; In addition to improving the mechanical properties such as the bearing capacity, ductility and toughness of the existing RC columns, from the construction perspective, the precast plates are modularly produced, and also have the advantages of short construction period, simple formwork support, strong practicability, good economy, environmental friendliness, etc. It effectively solves the technical problem of cumbersome process when high-strength stainless steel wire mesh reinforced ECC is used to strengthen RC columns in the prior art.

[0019] To solve the above problems, the construction method of the precast high-strength stainless steel wire mesh reinforced ECC member for strengthening RC columns provided by the present invention adopts the following technical solutions:

[0020] The construction method of the precast high-strength stainless steel wire mesh reinforced ECC member for strengthening RC columns includes the following steps:

[0021] S1: Roughcast and chamfer the surface of the RC column;

[0022] S2: Drill planted bar holes and expansion bolt holes at the designed positions at the root of the RC column and the upper part of the precast prestressed high-strength stainless steel wire mesh reinforced ECC plate according to the longitudinal steel strand spacing and the design requirements of the longitudinal pre-tightening device, and clean and air-dry them.

[0023] S3: Insert the longitudinal steel strands of the prefabricated prestressed high-strength stainless steel wire mesh-reinforced ECC plate into the rebar planting holes on one side, and fix the perforated angle iron at the upper position of the prefabricated prestressed high-strength stainless steel wire mesh-reinforced ECC plate using structural adhesive and expansion bolts.

[0024] S4: After the structural adhesive in the rebar planting holes cures, apply structural adhesive on the inner side of the prefabricated prestressed high-strength stainless steel wire mesh-reinforced ECC plate; fix the longitudinal steel strands of the prefabricated prestressed high-strength stainless steel wire mesh-reinforced ECC plate on the perforated angle iron using aluminum buckles, fish-eye screws and supporting nuts and apply prestress longitudinally; after the structural adhesive cures, pour slightly expanding high-strength grouting material on the inner side of the plate.

[0025] S5: After the slightly expanding high-strength grouting material cures, pass the reserved transverse steel strands of the prefabricated prestressed high-strength stainless steel wire mesh-reinforced ECC plate through the prefabricated reserved hole ECC plate, and then pass them through the positive-thread and reverse-thread fish-eye screws respectively; as in step S4, use the positive and negative tension nuts, structural adhesive, and slightly expanding high-strength grouting material.

[0026] S6: Stick the simple formwork on the prefabricated prestressed high-strength stainless steel wire mesh-reinforced ECC plate and the prefabricated reserved hole ECC plate, then spray foaming adhesive at the joints of the simple formwork, then fix the simple formwork using formwork fasteners, and finally pour the ECC post-cast strip. During the pouring process, relevant facilities such as vibrating rods and rubber hammers should be used to ensure dense pouring.

[0027] The beneficial effects of the construction method of the prefabricated high-strength stainless steel wire mesh-reinforced ECC component for strengthening RC columns provided by the present invention are as follows: By prefabricating the high-strength stainless steel wire mesh-reinforced ECC main body into plates and cooperating with the post-cast strip for reinforcement, the construction process is greatly simplified, the construction period is shortened, the labor demand is small, and at the same time, due to the small cross-sectional area of the post-cast strip, the influence of climate can be ignored. The combined use of structural adhesive, slightly expanding grouting material, and prestressing devices for steel strands in all directions ensures the effective bonding of the high-strength stainless steel wire mesh-reinforced ECC main body plate to the base surface, and prestress is applied in all directions, further giving full play to the excellent performance of the high-strength stainless steel wire mesh-reinforced ECC; In addition to improving the mechanical properties such as the bearing capacity, ductility and toughness of the existing RC columns, from the perspective of construction, the modular production of prefabricated plates also has the advantages of short construction period, simple formwork support, strong practicability, good economy, and environmental friendliness. It effectively solves the technical problem of the cumbersome process when high-strength stainless steel wire mesh-reinforced ECC is used to strengthen RC columns in the prior art. Description of the Drawings

[0028] By reading the following detailed description with reference to the accompanying drawings, the above and other objects, features, and advantages of the exemplary embodiments of the present invention will become readily understandable. In the drawings, several embodiments of the present invention are shown in an exemplary rather than restrictive manner, and the same or corresponding reference numerals represent the same or corresponding parts, wherein:

[0029] Figure 1 Schematic three-dimensional view of the application of the prefabricated high-strength stainless steel wire mesh reinforced ECC member for strengthening RC columns provided by the present invention Figure 1 ;

[0030] Figure 2 Schematic three-dimensional view of the application of the prefabricated high-strength stainless steel wire mesh reinforced ECC member for strengthening RC columns provided by the present invention Figure 2 (without showing the simple formwork);

[0031] Figure 3 Front view of the application of the prefabricated high-strength stainless steel wire mesh reinforced ECC member for strengthening RC columns provided by the present invention (showing the internal structure);

[0032] Figure 4 Side view of the application of the prefabricated high-strength stainless steel wire mesh reinforced ECC member for strengthening RC columns provided by the present invention (showing the internal structure);

[0033] Figure 5 Top view of the application of the prefabricated high-strength stainless steel wire mesh reinforced ECC member for strengthening RC columns provided by the present invention (showing the internal structure);

[0034] Figure 6 Schematic diagram of the ECC plate fixing device in the prefabricated high-strength stainless steel wire mesh reinforced ECC member for strengthening RC columns provided by the present invention;

[0035] Figure 7 Assembly schematic diagram of the transverse pre-tightening device in the prefabricated high-strength stainless steel wire mesh reinforced ECC member for strengthening RC columns provided by the present invention;

[0036] Figure 8 For Figure 7 Explosion schematic diagram of the transverse pre-tightening device in

[0037] Figure 9 Front view of the longitudinal pre-tightening device in the prefabricated high-strength stainless steel wire mesh reinforced ECC member for strengthening RC columns provided by the present invention;

[0038] Figure 10 For Figure 9 Left view of the longitudinal pre-tightening device in

[0039] Figure 11 For Figure 9Top view of the longitudinal pre-tightening device;

[0040] Figure 12 is Figure 1 top view of.

[0041] Explanation of reference numerals:

[0042] 1. RC column; 2. ECC plate fixing device; 201. Steel bonding adhesive; 202. Micro-expansion high-strength grouting material; 3. Prefabricated pre-reserved hole ECC plate; 4. Horizontal steel strand; 5. Reserved hole; 6. Horizontal pre-tightening device; 601. Aluminum buckle; 602. Positive-thread fish-eye screw; 603. Positive and negative tension nuts; 604. Reverse-thread fish-eye screw; 8. ECC post-cast strip; 9. Drilled hole for planting steel bars; 10. Steel bar planting adhesive; 11. Prefabricated prestressed high-strength stainless steel wire mesh reinforced ECC plate; 12. Longitudinal steel strand; 13. Longitudinal pre-tightening device; 1301. Angle iron with holes; 1302. Expansion bolt; 1303. Nut; 1304. Fish-eye screw; 14. Simple formwork. Embodiment

[0043] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Those skilled in the art should know that the embodiments described below are part of the embodiments of the present disclosure, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative efforts belong to the scope of protection of the present invention.

[0044] It should be noted that the main concept of the present invention is to prefabricate the high-strength stainless steel wire mesh reinforced ECC main body into plates and cooperate with the post-cast strip for reinforcement, which greatly simplifies the construction process, shortens the construction period, requires less labor, and at the same time, since the cross-sectional area of the post-cast strip is small, the influence of climate can be ignored. The combined use of the steel bonding adhesive 201, the micro-expansion grouting material, and the pre-tightening device for steel strands in all directions ensures the effective bonding of the high-strength stainless steel wire mesh reinforced ECC main body plate to the base surface and applies prestress in all directions, further giving full play to the excellent performance of the high-strength stainless steel wire mesh reinforced ECC.

[0045] After introducing the basic principles of the present invention, the various non-limiting embodiments of the present invention will be specifically introduced below. The number of any element in the accompanying drawings is for illustration rather than limitation, and any naming is only for distinction and does not have any limiting meaning.

[0046] Next, with reference to several representative embodiments of the present invention, the principles and spirit of the present invention will be elaborated in detail.

[0047] Embodiment of the prefabricated high-strength stainless steel wire mesh reinforced ECC member for strengthening RC columns provided by the present invention:

[0048] As Figures 1 to 12 shown, the precast high-strength stainless steel wire mesh reinforced ECC component for strengthening RC columns mainly includes a precast high-strength stainless steel wire mesh reinforced ECC plate component, an ECC post-cast strip 8, and an ECC plate fixing device 2.

[0049] Among them, the precast high-strength stainless steel wire mesh reinforced ECC plate component includes a precast prestressed high-strength stainless steel wire mesh reinforced ECC plate 11 arranged circumferentially around the RC column 1 and a precast reserved hole ECC plate 3. A high-strength stainless steel wire mesh formed by tying multiple transverse steel wires 4 and pre-longitudinal steel wires 12 is fixed in the precast prestressed high-strength stainless steel wire mesh reinforced ECC plate 11. The precast reserved hole ECC plate 3 is connected to the transverse steel wire 4. The longitudinal direction of the high-strength stainless steel wire mesh is connected with an anchor fixing device, and both the transverse and longitudinal directions are connected with a pre-tightening device.

[0050] The ECC post-cast strip 8 is used to fill the gap after the installation of the precast high-strength stainless steel wire mesh reinforced ECC plate component to counteract the residual stress; the ECC plate fixing device 2 is used to fix the precast high-strength stainless steel wire mesh reinforced ECC plate component circumferentially on the RC column 1.

[0051] The high-strength stainless steel wire mesh is arranged in the middle of the precast prestressed high-strength stainless steel wire mesh reinforced ECC plate 11 in the thickness direction, and the transverse steel wire 4 is arranged outside the pre-longitudinal steel wire 12.

[0052] Specifically, the RC column 1 is of a rectangular structure. The number of precast reserved hole ECC plates 3 on the rectangular surface of the RC column 1 with precast reserved hole ECC plates 3 is two, and the high-strength stainless steel wire mesh is located in the middle of the two precast reserved hole ECC plates 3.

[0053] Both ends of the multiple transverse steel wires 4 in the precast prestressed high-strength stainless steel wire mesh reinforced ECC plate 11 are respectively connected and fixed to the precast reserved hole ECC plates 3 adjacent to both sides of the precast prestressed high-strength stainless steel wire mesh reinforced ECC plate 11.

[0054] PVC pipes are embedded inside the precast prestressed high-strength stainless steel wire mesh reinforced ECC plate 11 and the precast reserved hole ECC plate 3 during casting. Reserved holes 5 are formed inside the PVC pipes to respectively supply the precast prestressed high-strength stainless steel wire mesh reinforced ECC plate 11 for installing the high-strength stainless steel wire mesh and supply the precast reserved hole ECC plate 3 for connecting the transverse steel wire 4.

[0055] Among them, the inner diameter of the embedded PVC pipe should be slightly larger than the nominal diameter of the steel wire. It is advisable to take d + 1 mm, where d is the diameter of the transverse steel wire 4 and the pre-longitudinal steel wire 12.

[0056] The ECC plate fixing device 2 includes a steel-bonding adhesive 201 for smearing on the edges of the precast prestressed high-strength stainless steel wire mesh reinforced ECC plate 11 and the precast reserved-hole ECC plate 3, and a slightly expanding high-strength grouting material 202 for pouring above the inner sides of the precast prestressed high-strength stainless steel wire mesh reinforced ECC plate 11 and the precast reserved-hole ECC plate 3 after the steel-bonding adhesive 201 cures.

[0057] The properties of both the steel-bonding adhesive 201 and the slightly expanding high-strength grouting material 202 should meet the index requirements specified in the Technical Specification for Safety Appraisal of Engineering Structure Strengthening Materials GB50728 - 2011; the smearing thickness of the steel-bonding adhesive 201 should preferably be 5 mm.

[0058] The anchor fixing device includes a rebar anchoring structure, and the rebar anchoring structure includes a rebar hole 9 and a rebar adhesive 10 provided at the root of the RC column 1; the pre-tightening device includes an angle iron with holes 1301, an expansion bolt 1302, a steel-bonding adhesive 201, a fish-eye screw 1304 and a matching nut 1303, and an aluminum buckle 601. One end of the longitudinal steel wire in the precast prestressed high-strength stainless steel wire mesh reinforced ECC plate 11 is implanted into the root of the RC column 1, and the other end is used to install and fix the angle iron with holes 1301 by the expansion bolt 1302 and the steel-bonding adhesive 201. The aluminum buckle 601 is used to connect with the fish-eye screw 1304 fixed on the angle iron with holes 1301 after the steel-bonding adhesive 201 and the rebar adhesive 10 in the rebar hole 9 cure, and the pre-stress degree is controlled by adjusting the position of the matching nut 1303.

[0059] The rebar hole 9 inclines 20° - 30° towards the RC column 1 side, and the projected length in the direction parallel to the side of the original concrete member is greater than or equal to 40d. The diameter of the rebar hole 9 is greater than or equal to d + 2 mm, where d is the diameter of the transverse steel strand 4 and the pre-longitudinal steel strand 12; the diameter of the transverse steel strand 4 and the pre-longitudinal steel strand 12 is 1.2 mm ≤ d ≤ 6 mm; the rebar adhesive 10 should meet the index requirements specified in the Technical Specification for Safety Appraisal of Engineering Structure Strengthening Materials GB50728 - 2011.

[0060] The dimensions and material properties of the angle iron with holes 1301, the expansion bolt 1302, the steel-bonding adhesive 201, the fish-eye screw 1304 and the matching nut 1303 should all be determined according to the dimensions of the existing RC column 1 and the precast prestressed high-strength stainless steel wire mesh reinforced ECC plate 11 to be used, and it is necessary to ensure that any part of the longitudinal pre-tightening device 13 does not fail prior to the strengthening layer itself.

[0061] The prefabricated and reserved duct ECC board 3 is connected with the transverse pre-tightening device 6, and the transverse pre-tightening device 6 includes a right-handed fish-eye screw 602 and a left-handed fish-eye screw 604, a positive and negative tension nut 603, and an aluminum buckle 601. During the reinforcement process, after the reserved transverse steel strands 4 of the prefabricated prestressed high-strength stainless steel wire mesh reinforced ECC board 11 pass through the prefabricated and reserved duct ECC board 3, the aluminum buckle 601 is used to connect with the right-handed fish-eye screw 602 and the left-handed fish-eye screw 604 respectively, and then the positive and negative tension nut 603 is used to tighten the right-handed fish-eye screw 602 and the left-handed fish-eye screw 604 to achieve the purpose of applying prestress.

[0062] In addition, the length of the positive and negative tension nut 603 is greater than or equal to 2 times that of the right-handed fish-eye screw 602 and the left-handed fish-eye screw 604; the selection principle of the dimensions and material properties of the right-handed fish-eye screw 602 and the left-handed fish-eye screw 604 is that they should not fail prior to the transverse steel strands 4.

[0063] Next, the ECC post-cast strip 8 is introduced. The ECC post-cast strip 8 is located at the root of the existing RC column 1, the corner of the column section, and the transverse pre-tightening device 6 of the steel strands.

[0064] Finally, the device also includes a simple formwork 14 surrounding the outer periphery of the prefabricated prestressed high-strength stainless steel wire mesh reinforced ECC board 11 and the prefabricated and reserved duct ECC board 3. The simple formwork 14 includes a formwork, formwork fasteners, and foaming glue. After the formwork is attached to the surface of the prefabricated ECC board, formwork fasteners are used to prevent the formwork from bulging outwards and expanding, and foaming glue is used at the bottom and joints of the formwork to prevent leakage of mortar.

[0065] The working principle of the prefabricated high-strength stainless steel wire mesh reinforced ECC member for strengthening RC columns provided by the present invention is as follows: by prefabricating the high-strength stainless steel wire mesh reinforced ECC main body into a board and cooperating with the post-cast strip for reinforcement, the construction process is greatly simplified, the construction period is accelerated, the labor demand is small, and at the same time, due to the small cross-sectional area of the post-cast strip, the influence of climate can be ignored. The combined use of the steel-bonding glue 201, the slightly expanding grouting material, and the pre-tightening devices for steel strands in all directions ensures the effective bonding between the high-strength stainless steel wire mesh reinforced ECC main body board and the base surface, and prestress is applied in all directions, further enabling the excellent performance of the high-strength stainless steel wire mesh reinforced ECC to be fully exerted; in addition to improving the mechanical properties such as the bearing capacity, ductility, and toughness of the existing RC column 1, from the construction perspective, the prefabricated board is modularly produced, and it also has the advantages of short construction period, simple formwork support, strong practicability, good economy, and environmental friendliness.

[0066] An embodiment of the construction method of the prefabricated high-strength stainless steel wire mesh reinforced ECC member for strengthening RC columns provided by the present invention:

[0067] The construction method of the prefabricated high-strength stainless steel wire mesh reinforced ECC member for strengthening RC columns includes the following steps:

[0068] S1: Roughcast and chamfer the surface of the RC column 1. The roughcasting should be done until the exposed coarse aggregate is reached, and the chamfer radius should not be less than 25 mm;

[0069] S2: Drill rebar planting holes 9 and expansion bolt 1302 holes at the designed positions on the root of the RC column 1 and the upper part of the precast prestressed high-strength stainless steel wire mesh reinforced ECC plate 11 according to the spacing of the pre-longitudinal steel strands 12 and the design requirements of the longitudinal pre-tightening device 13, and then clean and air-dry them;

[0070] S3: Insert one side of the pre-longitudinal steel strands 12 of the precast prestressed high-strength stainless steel wire mesh reinforced ECC plate 11 into the rebar planting holes 9, and fix the angle iron 1301 with holes at the upper position of the precast prestressed high-strength stainless steel wire mesh reinforced ECC plate 11 by using the steel-bonding adhesive 201 and the expansion bolt 1302. It should be noted that the precast prestressed high-strength stainless steel wire mesh reinforced ECC plate 11 should be arranged on the main stress side of the RC column 1;

[0071] S4: After the planting adhesive 10 in the rebar planting holes 9 is cured, apply the steel-bonding adhesive 201 on the inner side of the precast prestressed high-strength stainless steel wire mesh reinforced ECC plate 11, and the application width is preferably 10 mm; and fix the pre-longitudinal steel strands 12 of the precast prestressed high-strength stainless steel wire mesh reinforced ECC plate 11 on the angle iron 1301 with holes by using the aluminum buckle 601, the fish-eye screw and the supporting nut and apply prestress longitudinally; after the steel-bonding adhesive 201 is cured, pour the slightly expanding high-strength grouting material 202 on the inner side of the plate;

[0072] S5: After the slightly expanding high-strength grouting material 202 is cured, pass the reserved transverse steel strands 4 of the precast prestressed high-strength stainless steel wire mesh reinforced ECC plate 11 through the precast reserved hole duct ECC plate 3, and then pass them through the right-hand fish-eye screw 602 and the left-hand fish-eye screw 604 respectively; as in step S4, use the positive and negative tension nuts 603, the steel-bonding adhesive 201, and the slightly expanding high-strength grouting material 202;

[0073] S6: Stick the simple formwork 14 on the precast prestressed high-strength stainless steel wire mesh reinforced ECC plate 11 and the precast reserved hole duct ECC plate 3, then spray the foaming adhesive at the joints of the simple formwork 14, and then fix the simple formwork 14 by using the formwork buckle. Finally, pour the ECC post-cast strip 8, and relevant facilities such as vibrating rods and rubber hammers should be adopted during the pouring process to ensure dense pouring.

Claims

1. A precast high-strength stainless steel wire mesh reinforced ECC member for strengthening RC columns, characterized in that, Comprising: A precast high-strength stainless steel stranded wire mesh reinforced ECC plate assembly, which includes a precast prestressed high-strength stainless steel stranded wire mesh reinforced ECC plate and a precast reserved hole ECC plate arranged circumferentially around the RC column. In the precast prestressed high-strength stainless steel stranded wire mesh reinforced ECC plate, a high-strength stainless steel stranded wire mesh formed by tying multiple transverse steel stranded wires and longitudinal steel stranded wires is fixed. The precast reserved hole ECC plate is connected to the transverse steel stranded wire. The longitudinal connection of the high-strength stainless steel stranded wire mesh is provided with an anchor fixing device, and both the transverse and longitudinal directions are connected with a pre-tightening device; An ECC post-cast strip, which is used to fill the joint after the installation of the precast high-strength stainless steel stranded wire mesh reinforced ECC plate assembly to counteract the residual stress; An ECC plate fixing device, which is used to fix the precast high-strength stainless steel stranded wire mesh reinforced ECC plate assembly circumferentially on the RC column; The anchor fixing device includes a rebar anchoring structure, and the rebar anchoring structure includes a rebar hole and rebar glue provided at the root of the RC column. The pre-tightening device includes an angle iron with holes, an expansion bolt, a steel bonding glue, a fish-eye screw and a matching nut, and an aluminum buckle. One end of the longitudinal steel bar wire in the precast prestressed high-strength stainless steel stranded wire mesh reinforced ECC plate is implanted into the root of the RC column, and the other end is used to install and fix the angle iron with holes by using the expansion bolt and the steel bonding glue. The aluminum buckle is used to connect to the fish-eye screw fixed on the angle iron with holes after the steel bonding glue and the rebar glue in the rebar hole are cured.

2. The precast high-strength stainless steel wire mesh-reinforced ECC member for strengthening RC columns according to claim 1, wherein: The high-strength stainless steel stranded wire mesh is arranged in the middle in the thickness direction of the precast prestressed high-strength stainless steel stranded wire mesh reinforced ECC plate, and the transverse steel stranded wires are arranged outside the longitudinal steel stranded wires.

3. The precast high-strength stainless steel wire mesh reinforced ECC member for strengthening RC columns according to claim 1 or 2, wherein: The RC column is a rectangular structure, and the number of precast reserved hole ECC plates on the rectangular surface with precast reserved hole ECC plates is two, and the high-strength stainless steel stranded wire mesh is located in the middle of the two precast reserved hole ECC plates.

4. The precast high-strength stainless steel wire mesh-reinforced ECC member for strengthening RC columns according to claim 3, wherein: Both ends of the multiple transverse steel stranded wires in the precast prestressed high-strength stainless steel stranded wire mesh reinforced ECC plate are respectively connected and fixed to the precast reserved hole ECC plates adjacent to both sides of the precast prestressed high-strength stainless steel stranded wire mesh reinforced ECC plate.

5. The precast high-strength stainless steel wire mesh-reinforced ECC member for strengthening RC columns according to claim 1 or 2, characterized in that: When the precast prestressed high-strength stainless steel stranded wire mesh reinforced ECC plate and the precast reserved hole ECC plate are cast, PVC pipes are embedded inside them, and reserved holes are formed in the PVC pipes to respectively supply the precast prestressed high-strength stainless steel stranded wire mesh reinforced ECC plate to install the high-strength stainless steel stranded wire mesh and supply the precast reserved hole ECC plate to connect the transverse steel stranded wire.

6. The precast high-strength stainless steel wire mesh-reinforced ECC member for strengthening RC columns according to claim 1 or 2, characterized in that: The ECC plate fixing device includes a steel bonding glue for smearing on the edges of the precast prestressed high-strength stainless steel stranded wire mesh reinforced ECC plate and the precast reserved hole ECC plate, and a slightly expanded high-strength grouting material is poured above the inner sides of the precast prestressed high-strength stainless steel stranded wire mesh reinforced ECC plate and the precast reserved hole ECC plate after the steel bonding glue is cured.

7. The precast high-strength stainless steel wire mesh reinforced ECC member for strengthening RC columns according to claim 1, characterized in that: The rebar hole inclines 20°-30° towards the RC column side.

8. The precast high-strength stainless steel wire mesh-reinforced ECC member for strengthening RC columns according to claim 1 or 2, wherein: It also includes a simple formwork surrounding the outer periphery of the precast prestressed high-strength stainless steel stranded wire mesh reinforced ECC plate and the precast reserved hole ECC plate.

9. Construction plan for precast high-strength stainless steel wire mesh reinforced ECC components for strengthening RC columns, which is realized by means of the precast high-strength stainless steel wire mesh reinforced ECC components described in any one of the above claims 1 to 8, and is characterized in that, Including the following steps: S1: Roughcast and chamfer the surface of the RC column; S2: Drill rebar holes and expansion bolt holes at the designed positions at the root of the RC column and the upper part of the precast prestressed high-strength stainless steel wire mesh reinforced ECC board according to the longitudinal steel wire spacing and the design requirements of the longitudinal pre-tightening device, and clean and air-dry them. S3: Insert one side of the longitudinal steel wires of the precast prestressed high-strength stainless steel wire mesh reinforced ECC board into the rebar holes, and fix the perforated angle iron at the upper position of the precast prestressed high-strength stainless steel wire mesh reinforced ECC board by using structural adhesive and expansion bolts. S4: After the planting adhesive in the rebar holes cures, apply structural adhesive on the inner side of the precast prestressed high-strength stainless steel wire mesh reinforced ECC board; and fix the longitudinal steel wires of the precast prestressed high-strength stainless steel wire mesh reinforced ECC board on the perforated angle iron by using aluminum buckles, fish-eye screws and matching nuts and apply prestress longitudinally; after the structural adhesive cures, pour slightly expanding high-strength grouting material on the inner side of the board. S5: After the slightly expanding high-strength grouting material cures, pass the reserved transverse steel wires of the precast prestressed high-strength stainless steel wire mesh reinforced ECC board through the precast reserved duct ECC board, and then insert them into the right-hand thread and left-hand thread fish-eye screws respectively; as in step S4, fix the precast reserved duct ECC board by using right-hand and left-hand tension nuts, structural adhesive and slightly expanding high-strength grouting material and apply prestress transversely. S6: Paste the simple formwork on the precast prestressed high-strength stainless steel wire mesh reinforced ECC board and the precast reserved duct ECC board, then spray foaming adhesive at the joints of the simple formwork, then fix the simple formwork by using formwork buckles, and finally pour the ECC post-cast strip. During the pouring process, use a vibrating rod and / or a rubber hammer for vibrating actions to ensure dense pouring.

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