High-binding-force steel fiber for concrete

Abstract

The invention relates to a high-binding-force steel fiber for concrete applied to the technical field of steel fibers, on the basis that the steel fiber is bent for multiple times, a forked fiber matched with a steel fiber matrix is further arranged, the forked fiber and the steel fiber matrix can form a cross shape after being assembled, and when the steel fiber is combined with the concrete, the concrete can be in cross contact with the steel fiber, so that the steel fiber is formed. Compared with only bending treatment, even if the interior of the concrete is cracked and the steel fibers are stressed, the concrete is difficult to separate from the crossed steel fibers, and the crossed structure of the concrete and the steel fibers greatly improves the binding force with the concrete, so that the effect of improving the strength of the concrete is better; the crossed ends of the forked fibers and the steel fiber matrix can form'stone knots', so that the positions of the forked fibers are limited, the forked fibers and the steel fiber matrix are difficult to generate relative displacement, and the stability of the crossed steel fibers is effectively ensured.

Description

Technical Field

[0001] The present invention relates to a steel fiber, in particular to a high-bonding strength steel fiber for concrete applied in the technical field of steel fibers. Background Art

[0002] Steel fiber reinforced concrete is a novel multiphase composite material formed by incorporating randomly distributed short steel fibers into ordinary concrete. These randomly distributed steel fibers effectively inhibit the expansion of microcracks within the concrete and the formation of macrocracks, significantly improving the concrete's tensile, flexural, impact, and fatigue resistance, and exhibiting excellent ductility.

[0003] To improve the slip resistance and bonding strength with concrete, existing steel fibers are generally bent. For example, the three-dimensional steel fibers disclosed in the specification of Chinese patent CN203867073U and the ball-marked steel fibers disclosed in the specification of Chinese patent CN2359369Y make the steel fibers non-linear. However, since steel fibers are generally small, simply bending them is less effective in improving bonding strength and is difficult to adapt to the current development needs of high-strength concrete. Summary of the Invention

[0004] In view of the above-mentioned prior art, the technical problem to be solved by the present invention is that the bonding strength between the existing steel fibers processed only by bending and the concrete is poor.

[0005] In order to solve the above problems, the present invention provides a high-bonding strength steel fiber for concrete, comprising a steel fiber matrix, forked fibers that conflict with each other at both ends of the steel fiber matrix, and a plurality of three-dimensional sleeves uniformly wound around the forked fibers, the steel fiber matrix comprising a middle flat section, blunt bend sections fixedly connected to both ends of the middle flat section, two inclined sections fixedly connected to one end of the blunt bend section away from each other, two sharp bend sections fixedly connected to one end of the inclined section away from each other, two vertical flat sections fixedly connected to the lower ends of the sharp bend sections, and a flat bend section fixedly connected to the ends of the two vertical flat sections, the end of the flat bend section facing one side of the middle flat section, the plurality of three-dimensional sleeves being located between the two inclined sections, an inner limiting hole being bored on the inclined section, an outer limiting hole being bored at the bend of the flat bend section, the two ends of the forked fibers being movably passed through the two inner limiting holes and inserted into the adjacent outer limiting holes; The three-dimensional sleeve includes a spiral section wound around the forked fiber, an outward-folded extension section and an end ring fixedly connected to both ends of the spiral section, and the end ring is simultaneously sleeved on the forked fiber and the connection between the spiral section and the outward-folded extension section of the adjacent three-dimensional sleeve; The forked fiber includes a large diameter section and two reduced diameter sections fixedly connected to both ends of the large diameter section, the reduced diameter sections match the outer limiting holes, and the large diameter section matches the inner limiting holes. The production method of high-bonding steel fiber for concrete comprises the following steps: S1. First, the steel is drawn through different dies to obtain two types of steel wires with rectangular and circular cross-sections; S2. Steel wires with rectangular cross-sections are arranged side by side by brushing with a hydrosol, and then cut and segmented according to the target length of the steel fibers to obtain steel sheets. Then, holes are punched at both ends of each steel wire on the steel sheet to form inner and outer limit holes. Then, both ends of the steel sheet are bent three times, and the three bends at both ends are symmetrical to each other. S3. Winding the circular cross-section steel wire with surface-increasing sleeves at regular intervals, the surface-increasing sleeves being composed of a plurality of three-dimensional sleeves wound one behind the other, cutting the circular cross-section steel wire into sections to obtain a plurality of forked fibers with surface-increasing sleeves, and cutting both ends of the forked fibers to reduce their diameters; S4. First, one end of the forked fiber is passed through the inner limiting hole and the outer limiting hole on the same side in sequence, and then pressure is applied to the forked fiber to make it arc-shaped. Then, the other end of the forked fiber is passed through the inner limiting hole and the outer limiting hole on the other side in sequence. Finally, it is cleaned and dried to obtain a cross-dimensional high-binding strength steel fiber.

[0006] In the above-mentioned high-bonding strength steel fiber for concrete, on the basis of multiple bending of the steel fiber, a forked fiber matching the steel fiber matrix is ​​also provided. The two can form a cross shape after assembly. When combined with concrete, the concrete will be in cross contact with the steel fiber. Compared with the treatment of only bending, the bonding strength between the steel fiber and the concrete is greatly improved, so that the effect of improving the strength of the concrete is better.

[0007] As a further improvement of the present application, the bending angle of the blunt bend section is 120-150°, the bending angle of the sharp bend section is 30-60°, and the bending angle of the flat bend section is a right angle.

[0008] As a further improvement of the present application, the inner diameter of the inner limiting hole is larger than that of the outer limiting hole, and the inner diameter of the outer limiting hole is between the inner diameters of the large diameter section and the reduced diameter section. The forked fibers are in a horizontal state when not connected to the steel fiber matrix, and the length of the forked fibers is greater than the distance between the two vertical flat sections.

[0009] As another improvement of the present application, before performing step S4, the third bends at both ends of the steel sheet are first covered with a one-way tape. FiberFix tape is fixedly attached to the back of the one-way tape. When covering the one-way tape, the multiple protrusions on the one-way tape are aligned with the multiple external limiting holes and pass through the external limiting holes. Then, the surface of the one-way tape is sprayed with water to allow the water to penetrate the back of the one-way tape, thereby ensuring stable adhesion between the one-way tape and the steel sheet. During step S4, after the end of the reduced diameter section is inserted into the protrusion at the outer limiting hole, the reduced diameter section squeezes the internal space of the protrusion, causing the cement powder inside to mix with water, while causing the end of the protrusion to increase abnormally. Subsequently, the cement powder is mixed with water and hardened, thereby forming a "stone lump" at the end of the forked fiber across the flat bend section, limiting the position of the forked fiber and making it difficult for it to move relative to the steel fiber matrix.

[0010] As another improved supplement to the present application, the one-way patch includes a plurality of membranes bonded in sequence by hydrosol and a plurality of pre-expanded protrusions fixedly connected to the back of the membranes. The membrane has a double-layer structure, and the layer of the membrane away from the pre-expanded protrusions is a hard porous structure, and the other layer of the membrane is made of a hard water-absorbent material.

[0011] As another improved supplement to the present application, the pre-expanded protrusion includes a forming section fixedly connected to the diaphragm, an outer sleeve fixedly connected to the outer end of the forming section, and a covering layer fixedly connected to the inner wall of the forming section close to the outer sleeve. The outer sleeve is filled with water, the covering layer is filled with cement powder, and the mouth of the forming section is sealed by an elastic membrane.

[0012] As another improved supplement of the present application, the outer sleeve is made of a highly elastic silicone material, the coating layer is made of a thin sealing material, the molding section is a hard molding structure, and the inner diameter of the molding section is consistent with the reduced diameter section.

[0013] In summary, on the basis of multiple bending of the steel fibers, forked fibers matching the steel fiber matrix are also provided. The two can form a cross shape after assembly. When combined with concrete, the concrete will be in cross contact with the steel fibers. Compared with the treatment of only bending, even if the concrete cracks and the steel fibers are subjected to stress, it is difficult to separate the concrete from the crossed steel fibers. The cross structure of the two greatly improves the bonding force between the concrete and the concrete, which has a better effect on improving the strength of the concrete. In addition, with the operation of one-way pasting, the ends of the forked fibers and the steel fiber matrix can be formed into "stone lumps", thereby limiting the position of the forked fibers, making it difficult for them to be relatively displaced with the steel fiber matrix, thereby effectively ensuring the stability of the cross-shaped steel fibers. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a three-dimensional diagram of the steel fiber according to the first embodiment of the present application; Figure 2 This is a three-dimensional diagram of the first embodiment of the present application when the forked fiber is not installed in the steel fiber matrix; Figure 3 This is an exploded schematic diagram of the separation of the forked fibers from the multiple three-dimensional sleeves according to the first embodiment of the present application; Figure 4 This is a front view of a steel fiber matrix according to a first embodiment of the present application; Figure 5 This is a front view comparison diagram of the steel fiber matrix before and after being installed into forked fibers according to the first embodiment of the present application; Figure 6 This is a schematic diagram of the second embodiment of the present application during the one-way tape application process; Figure 7 This is a schematic diagram of the outer limiting hole portion on the side of the one-way patch in the second embodiment of the present application; Figure 8 This is a schematic diagram of the side of a one-way sticker according to the second embodiment of the present application; Figure 9 This is a schematic diagram of the second embodiment of the present application when the forked fiber end portion is inserted into the protrusion of the unidirectional tape; Figure 10 This is a front view of the steel fiber with "stone lumps" in the second embodiment of this application.

[0015] Description of the numbers in the figure: 1 steel fiber matrix, 101 inner limiting hole, 102 outer limiting hole, 11 middle flat section, 12 inclined section, 13 vertical flat section, 141 blunt bend section, 142 sharp bend section, 143 flat bend section, 2 forked fiber, 21 large diameter section, 22 reduced diameter section, 3 three-dimensional sleeve, 31 spiral section, 32 outward folded extension section, 33 end ring, 41 diaphragm, 42 pre-expanded protrusion, 421 shaping section, 422 coating layer, 423 outer sleeve. DETAILED DESCRIPTION

[0016] Two implementation modes of the present application are described in detail below with reference to the accompanying drawings.

[0017] The first implementation method: Figure 1-2FIG1 shows a high-bonding steel fiber for concrete, comprising a steel fiber matrix 1, forked fibers 2 mutually abutting against each other at both ends of the steel fiber matrix 1, and a plurality of three-dimensional sleeves 3 uniformly wound around the forked fibers 2, and the two three-dimensional sleeves 3 at the edge respectively abut against the adjacent inclined sections 12, thereby effectively ensuring the stability of the plurality of three-dimensional sleeves 3 on the forked fibers 2, making it difficult for them to move along the forked fibers 2, thereby making them more stable when combined with concrete. The steel fiber matrix 1 comprises a flat section 11, blunt bend sections 141 respectively fixedly connected to both ends of the flat section 11, and two blunt bend sections 141 respectively fixedly connected to the blunt bend sections 141 mutually abutting against each other. An inclined surface section 12 away from one end, two sharp bend sections 142 respectively fixedly connected to the inclined surface section 12 at one end away from each other, two vertical flat sections 13 respectively fixedly connected to the lower ends of the sharp bend sections 142, and a flat bend section 143 fixedly connected to the ends of the two vertical flat sections 13, the ends of the flat bend sections 143 facing the side of the middle flat section 11, multiple three-dimensional sleeves 3 are located between the two inclined surface sections 12, an inner limiting hole 101 is bored on the inclined surface section 12, and an outer limiting hole 102 is bored at the bend of the flat bend section 143, and the two ends of the forked fiber 2 are respectively movable through the two inner limiting holes 101 and inserted into the adjacent outer limiting holes 102; Figure 4 The bending angle of the blunt bend section 141 is 120-150°, the bending angle of the sharp bend section 142 is 30-60°, and the bending angle of the flat bend section 143 is a right angle.

[0018] like Figure 3 The three-dimensional sleeve 3 includes a spiral section 31 wound around the forked fiber 2, an outward-folded extension section 32 and an end ring 33 fixedly connected to both ends of the spiral section 31. The end ring 33 is simultaneously sleeved on the connection between the spiral section 31 and the outward-folded extension section 32 of the forked fiber 2 and the adjacent three-dimensional sleeve 3, so that the end ring 33 on the adjacent three-dimensional sleeve 3 can press the end of the adjacent three-dimensional sleeve 3, so that the outward-folded extension section 32 at the end can stably extend outward and is not easy to loosen, thereby enabling the steel fiber to be subjected to multi-directional forces when combined with concrete, thereby improving the bonding strength between the steel fiber and the concrete; like Figure 1-2The forked fiber 2 includes a large diameter section 21 and two reduced diameter sections 22 fixedly connected to both ends of the large diameter section 21. The reduced diameter section 22 matches the outer limiting hole 102, and the large diameter section 21 matches the inner limiting hole 101. The inner diameter of the inner limiting hole 101 is larger than that of the outer limiting hole 102, and the inner diameter of the outer limiting hole 102 is between the inner diameters of the large diameter section 21 and the reduced diameter section 22. When the forked fiber 2 is not connected to the steel fiber matrix 1, it is in a horizontal state, and the length of the forked fiber 2 is greater than the distance between the two vertical flat sections 13. When it passes through the inner limiting hole 101 and the outer limiting hole 102 and is connected to the steel fiber matrix 1, its two ends will be subjected to resistance force, and then take on an arc shape, so that the connection stability of the forked fiber 2 and the steel fiber matrix 1 is higher and it is not easy to separate. At the same time, the crossing amplitude between the two is increased, so that the concrete can be more embedded between the steel fiber matrix 1 and the forked fiber 2, thereby forming a cross-mixing relationship with the concrete. Compared with the prior art in which only a single steel fiber is bent at the end, the bonding strength between the steel fiber and the concrete is significantly improved.

[0019] The production method of high-bonding steel fiber for concrete comprises the following steps: S1. First, the steel is drawn through different dies to obtain two types of steel wires with rectangular and circular cross-sections; S2. Steel wires with rectangular cross-sections are arranged side by side by brushing with a hydrosol, and then cut and segmented according to the target length of the steel fibers to obtain steel sheets. Then, holes are punched at both ends of each steel wire on the steel sheet to form inner limiting holes 101 and outer limiting holes 102. Then, both ends of the steel sheet are bent three times, and the three bends at both ends are symmetrical to each other. S3. Surface-enhancing sleeves are wound around the circular cross-section steel wire at regular intervals. The surface-enhancing sleeves are composed of multiple three-dimensional sleeves 3 wrapped in a front-to-back manner. The circular cross-section steel wire is cut into sections to obtain multiple forked fibers 2 with surface-enhancing sleeves. The ends of the forked fibers 2 are cut to reduce their diameters. S4, such as Figure 5 First, one end of the forked fiber 2 is passed through the inner limiting hole 101 and the outer limiting hole 102 on the same side in sequence, then the forked fiber 2 is pressurized to make it arc-shaped, and then the other end of the forked fiber 2 is passed through the inner limiting hole 101 and the outer limiting hole 102 on the other side in sequence, and finally through cleaning and drying treatment, a cross-dimensional high-binding strength steel fiber is obtained.

[0020] In the above-mentioned high-bonding strength steel fiber for concrete, on the basis of multiple bending of the steel fiber, a forked fiber 2 matching the steel fiber matrix 1 is also provided. The two can form a cross shape after assembly. When combined with concrete, the concrete will be in cross contact with the steel fiber. Compared with the treatment of only bending, the bonding strength between the steel fiber and the concrete is greatly improved, so that the effect of improving the strength of the concrete is better.

[0021] The second implementation method: This embodiment is based on the first embodiment, and adds a one-way tape processing operation, and the rest of the parts are consistent with the first embodiment.

[0022] Figure 6-7 As shown, b in the figure represents a one-way sticker. Before performing step S4, the third bends at both ends of the steel sheet are first covered with a one-way sticker. The back of the one-way sticker is fixedly attached with FiberFix tape. The FiberFix tape will produce super strong adhesion when it comes into contact with water, so that it can be stably bonded to the steel fiber matrix 1. When covering the one-way sticker, the multiple protrusions on the one-way sticker are aligned with the multiple external limiting holes 102 and pass through the external limiting holes 102. Then, the surface of the one-way sticker is sprayed with water to allow water to penetrate into the back of the one-way sticker, so that the one-way sticker is stably bonded to the steel sheet. During step S4, after the end of the reduced diameter section 22 is inserted into the protrusion at the outer limiting hole 102, the reduced diameter section 22 squeezes the internal space of the protrusion, causing the cement powder inside to mix with water, while causing the end of the protrusion to increase abnormally. Subsequently, the cement powder is mixed with water and hardened, thereby forming a "stone lump" at the end of the forked fiber 2 across the flat bend section 143, limiting the position of the forked fiber 2 and making it difficult for it to move relative to the steel fiber matrix 1.

[0023] like Figure 7 The one-way patch includes a plurality of membranes 41 bonded in sequence by hydrosols and a plurality of pre-expanded protrusions 42 fixedly connected to the back of the membranes 41. The membrane 41 is a double-layer structure, and a layer of the membrane 41 away from the pre-expanded protrusions 42 is a hard porous structure, and the other layer of the membrane 41 is made of a hard water-absorbing material. When spraying water, the water can penetrate along the porous structure to the back and then contact the FiberFix tape, making it sticky, so that the one-way patch can be stably bonded to the steel fiber matrix 1, facilitating the subsequent stable formation of the "stone lump" in which the forked fibers 2 extend to the outer end of the steel fiber matrix 1.

[0024] like Figure 8 The pre-expanded convex head 42 includes a shaping section 421 fixedly connected to the diaphragm 41, an outer sleeve 423 fixedly connected to the outer end of the shaping section 421, and a coating layer 422 fixedly connected to the inner wall of the shaping section 421 near the outer sleeve 423. The outer sleeve 423 is filled with water, the coating layer 422 is filled with cement powder, and the mouth of the shaping section 421 is sealed by an elastic membrane. The outer sleeve 423 is made of highly elastic silicone material, the coating layer 422 is made of a thin sealing material, the shaping section 421 is a hard shaping structure, and the inner diameter of the shaping section 421 is consistent with the diameter-reducing section 22. When performing step S4, the diameter-reducing section 22 enters the pre-expanded convex head 42, which will squeeze the cement powder to make it continue to move inward. Figure 9-10In the figure, a represents a "stone lump". On the one hand, the end of the pre-expanded protrusion 42 is gradually expanded. At the same time, the thin coating layer 422 will be broken first under the extrusion of the diameter-reducing section 22. At this time, water contacts with cement powder and hardens, thereby forming a larger "stone lump" at the end of the diameter-reducing section 22, making it difficult to detach from the outer limit hole 102. Compared with the first embodiment, the relative stability between the steel fiber matrix 1 and the forked fiber 2 is greatly improved.

[0025] In summary, on the basis of multiple bending of the steel fibers, forked fibers 2 are provided to match the steel fiber matrix 1. The two can form a cross shape after assembly. When combined with concrete, the concrete will be in cross contact with the steel fibers. Compared with the treatment of only bending, even if the concrete cracks and the steel fibers are subjected to stress, it is difficult to separate the concrete from the crossed steel fibers. The cross structure of the two greatly improves the bonding force between the concrete and the concrete, which has a better effect on improving the strength of the concrete. In addition, in conjunction with the operation of one-way pasting, the ends of the forked fibers 2 and the steel fiber matrix 1 can be formed into "stone lumps", thereby limiting the position of the forked fibers 2, making it difficult for them to have relative displacement with the steel fiber matrix 1, thereby effectively ensuring the stability of the cross-shaped steel fibers.

[0026] In view of current actual needs, the protection scope of the above-mentioned implementation mode adopted in this application is not limited to this. Various changes made within the knowledge scope of technical personnel in this field without departing from the concept of this application still fall within the protection scope of the present invention.

Claims

1. A high-bonding steel fiber for concrete, characterized in that: The invention comprises a steel fiber matrix (1), forked fibers (2) mutually abutting against the two ends of the steel fiber matrix (1), and a plurality of three-dimensional sleeves (3) uniformly wound around the forked fibers (2), wherein the steel fiber matrix (1) comprises a middle flat section (11), blunt bend sections (141) respectively fixedly connected to the two ends of the middle flat section (11), two inclined sections (12) respectively fixedly connected to the blunt bend sections (141) at one end away from each other, two sharp bend sections (142) respectively fixedly connected to the inclined sections (12) at one end away from each other, and two sharp bend sections (143) respectively fixedly connected to the sharp bend sections (144). 2) a vertical flat section (13) at the lower end and a flat curved section (143) fixedly connected to the ends of the two vertical flat sections (13), the ends of the flat curved sections (143) facing the middle flat section (11), the plurality of three-dimensional sleeves (3) are located between the two inclined sections (12), the inclined sections (12) are provided with inner limiting holes (101), the bent portions of the flat curved sections (143) are provided with outer limiting holes (102), and the two ends of the forked fibers (2) are respectively movable through the two inner limiting holes (101) and inserted into adjacent outer limiting holes (102); The three-dimensional sleeve (3) comprises a spiral section (31) wound around the outside of the forked fiber (2), and an outwardly folded extension section (32) and an end ring (33) respectively fixedly connected to both ends of the spiral section (31); the end ring (33) is simultaneously sleeved on the connection between the spiral section (31) and the outwardly folded extension section (32) of the forked fiber (2) and the adjacent three-dimensional sleeve (3); The forked fiber (2) comprises a large diameter section (21) and two reduced diameter sections (22) respectively fixedly connected to both ends of the large diameter section (21), the reduced diameter sections (22) matching the outer limiting holes (102), and the large diameter section (21) matching the inner limiting holes (101); The production method of high-bonding steel fiber for concrete comprises the following steps: S1. First, the steel is subjected to wire drawing through different dies to obtain two types of steel wires with rectangular and circular cross-sections; S2, steel wires with rectangular cross-sections are arranged side by side by brushing glue, and then cut and segmented according to the target length of the steel fibers to obtain steel sheets, and then both ends of each steel wire on the steel sheet are punched to form an inner limit hole (101) and an outer limit hole (102), and then both ends of the steel sheet are bent three times, and the three bends at both ends are symmetrical to each other; S3, winding a surface increasing sleeve at a certain interval outside the steel wire with a circular cross section, the surface increasing sleeve being composed of a plurality of three-dimensional sleeves (3) bundled and wound in front and behind, cutting the steel wire with a circular cross section into sections to obtain a plurality of forked fibers (2) with the surface increasing sleeves, and cutting the two ends of the forked fibers (2) to reduce the diameter of the end portions; S4, firstly, one end of the forked fiber (2) is passed through the inner limiting hole (101) and the outer limiting hole (102) on the same side in sequence, then the forked fiber (2) is pressurized to make it present an arc shape, then the other end of the forked fiber (2) is passed through the inner limiting hole (101) and the outer limiting hole (102) on the other side in sequence, and finally, it is washed and dried to obtain a cross-three-dimensional high-binding strength steel fiber.

2. The high-bonding steel fiber for concrete according to claim 1, characterized in that: The bending angle of the blunt bend section (141) is 120-150°, the bending angle of the sharp bend section (142) is 30-60°, and the bending angle of the flat bend section (143) is a right angle.

3. The high-bonding steel fiber for concrete according to claim 1, characterized in that: The inner diameter of the inner limiting hole (101) is greater than that of the outer limiting hole (102), and the inner diameter of the outer limiting hole (102) is between the inner diameters of the large diameter section (21) and the reduced diameter section (22); the forked fiber (2) is in a horizontal state when not connected to the steel fiber matrix (1), and the length of the forked fiber (2) is greater than the distance between the two vertical flat sections (13).

4. The high-bonding steel fiber for concrete according to claim 1, characterized in that: Before performing step S4, the third bending parts at both ends of the steel sheet are first covered with a one-way sticker, and the back of the one-way sticker is fixedly attached with a FiberFix tape. When covering the one-way sticker, the plurality of protrusions on the one-way sticker are aligned with the plurality of external limiting holes (102) and penetrate the external limiting holes (102), and then the surface of the one-way sticker is sprayed with water to allow the water to penetrate into the back of the one-way sticker, so that the one-way sticker and the steel sheet are stably bonded; During step S4, after the end of the reduced diameter section (22) is inserted into the protrusion at the outer limiting hole (102), the reduced diameter section (22) squeezes the internal space of the protrusion, causing the cement powder inside to mix with water, while causing the end of the protrusion to increase abnormally. Subsequently, the cement powder mixes with water and hardens, thereby forming a "stone lump" at the end of the bifurcated fiber (2) across the flat bend section (143), limiting the position of the bifurcated fiber (2) and making it difficult for the bifurcated fiber (2) to be displaced relative to the steel fiber matrix (1).

5. The high-bonding steel fiber for concrete according to claim 4, characterized in that: The one-way patch comprises a plurality of membrane sheets (41) bonded in sequence by means of a hydrosol, and a plurality of pre-expanded protrusions (42) respectively fixedly connected to the back of the membrane sheets (41). The membrane sheets (41) are of a double-layer structure, and a layer of the membrane sheet (41) away from the pre-expanded protrusions (42) is of a hard porous structure, and another layer of the membrane sheet (41) is made of a hard water-absorbent material.

6. The high-bonding steel fiber for concrete according to claim 5, characterized in that: The pre-expanded protrusion (42) comprises a shaping section (421) fixedly connected to the diaphragm (41), an outer sleeve (423) fixedly connected to the outer end of the shaping section (421), and a coating layer (422) fixedly connected to the inner wall of the shaping section (421) on one side close to the outer sleeve (423), the outer sleeve (423) is filled with water, the coating layer (422) is filled with cement powder, and the mouth of the shaping section (421) is sealed by an elastic membrane.

7. The high-bonding steel fiber for concrete according to claim 6, characterized in that: The outer sleeve (423) is made of a highly elastic silicone material, the coating layer (422) is made of a thin sealing material, the shaping section (421) is a hard shaping structure, and the inner diameter of the shaping section (421) is consistent with that of the reduced diameter section (22).

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