Concrete structure strengthened using grid reinforcement material and non-shrink grout and method of strengthening the same

Patent metadata

Field	Value
Publication number	US-2022186510-A1
Application number	US-202117338679-A
Country	US
Kind code	A1
Filing date	Jun 4, 2021
Priority date	Dec 14, 2020
Publication date	Jun 16, 2022
Grant date	—

Abstract

The present disclosure provides a concrete structure strengthened using a grid reinforcement material and non-shrink grout and a method of strengthening the same in which, when strengthening a concrete structure such as a concrete slab or a concrete wall body that is damaged or deteriorated, a grid reinforcement material is mounted on one side of the concrete structure, a formwork is formed on an outer side of the grid reinforcement material to have a required gap, and then the gap is filled with non-shrink grout so that the non-shrink grout is cured therein to strengthen the old concrete structure, thereby being able to automatically fill and repair cracks formed in the concrete structure just by injecting the non-shrink grout without separately performing crack repair on the old concrete structure. Also, the grid reinforcement material may be easily fixed or mounted using a grid fixing device and may be easily applied to strengthening of a concrete structure having a curved surface as well as a concrete structure having a flat surface such as a concrete slab or a concrete wall body. In addition, reinforcing bars may be additionally arranged in a gap between a surface of the concrete structure and the grid reinforcement material so that the grid reinforcement material increases a cover thickness, and thus the concrete structure is remarkably strengthened.

First claim

What is claimed is:

1 . A concrete structure strengthened using a grid reinforcement material and non-shrink grout, which is an old concrete structure that is damaged or deteriorated, the concrete structure comprising:
a structure to be strengthened of which one side is filled with a grid reinforcement material and non-shrink grout to be strengthened; the grid reinforcement material, which is a lattice-type textile grid, installed to be spaced apart at predetermined intervals on the structure to be strengthened; grid fixing devices each of which includes a first retainer and a second retainer and allows the grid reinforcement material to be inserted and fixed between the first retainer and the second retainer so that the grid reinforcement material is mounted on or fixed to the structure to be strengthened; and the non-shrink grout injected and filled through a formwork installed to be spaced apart from the grid reinforcement material, wherein a crack in the structure to be strengthened is automatically filled with the non-shrink grout to strengthen the structure to be strengthened.

2 . The concrete structure of claim 1 , wherein the grid reinforcement material is a carbon fiber textile grid made of an incombustible material to improve the fire resistance of the structure to be strengthened.

3 . The concrete structure of claim 1 , wherein the structure to be strengthened is an old concrete slab or an old concrete wall body that is damaged or deteriorated.

4 . The concrete structure of claim 3 , wherein, when the structure to be strengthened is a concrete slab, the grid fixing device includes:
a first retainer which has a first through-hole formed in a central portion and which comes in direct contact with the lattice-type grid reinforcement material so that the grid reinforcement material is fixed; a cylindrical spacer which has a second through-hole corresponding to the first through-hole formed therein and which is integrally formed with a lower surface of the first retainer so that the first retainer maintains a predetermined distance from the structure to be strengthened; an anchor pin which is tacked using a tacker or tacking device and which passes through the first through-hole and the second through-hole to be tacked into the structure to be strengthened; and a second retainer which is formed to be stacked on the first retainer, has a through-hole formed in a central portion, and comes in direct contact with the grid reinforcement material.

5 . The concrete structure of claim 3 , wherein, when the structure to be strengthened is a concrete wall body, the grid fixing device includes:
a first retainer which has a first through-hole formed in a central portion and which comes in direct contact with the lattice-type grid reinforcement material so that the grid reinforcement material is fixed; a spacing pin which passes through the first through-hole of the first retainer to maintain a distance between the structure to be strengthened and a wall body side surface formwork; and a second retainer which is formed to be stacked on the first retainer, has a through-hole formed in a central portion, and comes in direct contact with the grid reinforcement material.

6 . The concrete structure of claim 1 , wherein the non-shrink grout is non-shrink mortar formed by mixing 100 parts by weight of cement, 25 to 35 parts by weight of fine blast-furnace slag powder, 2 to 3 parts by weight of silica fume, 140 to 150 parts by weight of fine aggregate, 40 to 50 parts by weight of water, 1.5 to 2.5 parts by weight of a high-performance water reducing agent, and 1.2 to 2 parts by weight of a polymer expansion material.

7 . The concrete structure of claim 1 , wherein reinforcing bars are additionally arranged between the structure to be strengthened and the grid reinforcement material, and the grid reinforcement material serves to increase a cover thickness to prevent corrosion of the reinforcing bars.

8 . A method of strengthening a concrete structure using a grid reinforcement material and non-shrink grout, the method comprising:
a) cleaning a surface of a structure to be strengthened that is damaged or deteriorated; b) fixing a grid fixing device including a first retainer, a spacer, and an anchor pin to the structure to be strengthened; c) mounting a grid reinforcement material on the first retainer of the grid fixing device; d) fastening a second retainer of the grid fixing device so that the anchor pin passes therethrough to fix the grid reinforcement material; e) installing an air vent and a slab side end portion formwork on each side end portion of the structure to be strengthened; f) installing a slab lower portion formwork on the slab side end portion formwork and installing at least one or more grout injection holes in the slab lower portion formwork; g) injecting and filling non-shrink grout through the grout injection hole ( 160 ) and allowing the non-shrink grout to cure; and h) when curing of the non-shrink grout is completed, removing the slab lower portion formwork and the slab side end portion formwork to finish strengthening of the structure to be strengthened, wherein a crack in the structure to be strengthened is automatically filled with the non-shrink grout to strengthen the structure to be strengthened.

9 . The method of claim 8 , wherein the structure to be strengthened is an old concrete slab that is damaged or deteriorated, and a lower portion of the slab may be strengthened.

10 . The method of claim 8 , wherein the grid reinforcement material of step c) is a carbon fiber textile grid made of an incombustible material to improve the fire resistance of the structure to be strengthened.

11 . The method of claim 8 , wherein, in step d), the grid reinforcement material is inserted and fixed between the first retainer and the second retainer.

12 . The method of claim 8 , wherein the grid fixing device includes:
the first retainer which has a first through-hole formed in a central portion and which comes in direct contact with the lattice-type grid reinforcement material so that the grid reinforcement material is fixed; the cylindrical spacer which has a second through-hole corresponding to the first through-hole formed therein and which is integrally formed with a lower surface of the first retainer so that the first retainer maintains a predetermined distance from the structure to be strengthened; the anchor pin which is tacked using a tacker or tacking device and which passes through the first through-hole and the second through-hole to be tacked into the structure to be strengthened; and the second retainer which is formed to be stacked on the first retainer, has a through-hole formed in a central portion, and comes in direct contact with the grid reinforcement material.

13 . The method of claim 8 , wherein, in step g), the non-shrink grout injected through the grout injection hole is injected and filled while air discharge is controlled through the air vent.

14 . The method of claim 8 , wherein the non-shrink grout is non-shrink mortar formed by mixing 100 parts by weight of cement, 25 to 35 parts by weight of fine blast-furnace slag powder, 2 to 3 parts by weight of silica fume, 140 to 150 parts by weight of fine aggregate, 40 to 50 parts by weight of water, 1.5 to 2.5 parts by weight of a high-performance water reducing agent, and 1.2 to 2 parts by weight of a polymer expansion material.

15 . A method of strengthening a concrete structure using a grid reinforcement material and non-shrink grout, the method comprising:
a) cleaning a surface of a structur

Assignees

• Korea Inst Civil Eng & Building Tech

Inventors

• Kim Hyeong Yeol
• Ryu Gum Sung
• You Young Jun
• An Gi Hong

Classifications

• E04C5/206

  Spacers having means to adapt the spacing distance · CPC title

• E04C5/168

  Spacers connecting parts for reinforcements and spacing the reinforcements from the form · CPC title

• F16B19/14

  Bolts or the like for shooting into concrete constructions, metal walls or the like by means of detonation-operated nailing tools (tools therefor B25C, B27F) · CPC title

• F16B5/065

  the plates being one on top of the other and distanced from each other, e.g. by using protrusions to keep contact and distance · CPC title

• F16B2/12

  using sliding jaws · CPC title