Pasted steel plate reinforcement
Paste steel plate reinforcement method
This method is to apply epoxy based liquid binder to the whole steel plate and then press it on the crack position to be repaired.
Sticking steel construction technology: process: paste surface treatment, adhesive preparation, glue and paste, inspection

1. Paste surface treatment

1.1. The concrete surface shall be chipped to remove the coating layer, oil scale and dirt, and then the 1-2mm thick surface layer shall be removed by grinding with Angle grinder. The larger depression shall be repaired and leveled with leveling adhesive, and the floating dust shall be blown clean with compressed air after grinding.
1.2. The adhesive surface of the steel plate shall be rough and rust-removing treated with Angle grinder until burnish occurs. If it is clean, wipe it with dry cloth before use.
Use cotton cloth to dip acetone to wipe clean surface otherwise, wait for completely dry backup.
1.3. Main materials used in this process: goggles, dust mask, impact hammer and flat shovel, hammer, Angle grinder, diamond grinder, grinding wheel, air compressor, cotton cloth, acetone.

2. Preparation of adhesive

2.1. The structural glue of the building is made up of two components, A and B. Take the clean container (plastic or metal basin, no oil, water and impurities) and the weighing device and mix them according to the proportion specified in the instructions, and use the agitator to stir for 5-10 minutes until the color is uniform.
When mixing, it is better to stir in the same direction to avoid air bubbles. The place should be well ventilated.
2.2. Main materials used in this process: agitator, container, weighing device, greasy knife and gloves.

Glue and paste

Adhesive dispensing, with be bored with knife daub on the has to deal with steel plate (or concrete), glue the appropriate section into triangles, about 3 mm thick, middle thick edge 1 mm or so, and then paste the steel plate in the concrete surface, prepared with fixed pressure system, proper pressure, seam with a glue liquid from plate extrusion.
The main materials used in this process: pressure fixation and unloading system, greasy knife, gloves.

4. Inspection

Jgn-g structure adhesive has excellent operation performance and can reach 100% full degree in normal operation.
Small hammer can be used to gently hit the paste steel plate during inspection, and the paste effect can be judged from the sound.
If the effective bonding area of the anchorage area is less than 90% and the effective bonding area of the non-anchorage area is less than 70%, the steel plate shall be stripped and re-pasted.
For important components, load test can also be used, and the standard value of graded loading to normal load is generally adopted. The test results are more intuitive and reliable, but the cost is higher and the time consumption is longer.
Jack or counterweight (commonly used sandbag, brick), dial indicator, crack microscope, weighing device is required.

5. Scope of application of steel bonding reinforcement technology:

(1) this method is applicable to the general flexural and tensile members subjected to static forces.
(2) this method by environmental temperature does not exceed 60 ℃, relative humidity is not more than 70% and no chemical corrosion of applicable conditions in the limit, otherwise should take effective protective measures.
(3) the adhesive used in this method refers to the structural adhesive with sufficient test basis and performance meeting the requirements of use, which has been identified by the relevant departments of the state.
(4) when the concrete strength of members is lower than C15, this method is not suitable for reinforcement.
When is the concrete application of structural steel bonding reinforcement usually:
(1) fracture reinforcement at the welding point of steel bars
(2) leakage of reinforcement during construction
(3) if the concrete mark cannot be reached, the structural strength shall be strengthened
(4) seismic reinforcement with additional layers
(5) balcony root fracture reinforcement
(6) strengthening the joint of the cow leg
(7) hoisting crane girder is strengthened by increasing load
(8) concentrated floor load reinforcement
(9) beam and column concrete burned out after the fire reinforcement
(10) concrete column leg fracture reinforcement
(11) bridge crane beam reinforcement
(12) fracture reinforcement of thin abdominal girder
(13) the beam body is strengthened by the blast wave
(14) enhance the floor load reinforcement
(15) the lower chord of roof frame beam is severely corroded and reinforced with exposed bars
(16) strengthening broken beams
(17) reinforcement of truncated columns
(18) earthquake absorption and reinforcement
(19) the beam and column are strengthened by chemically corroded sticky steel
(20) comprehensive reinforcement for the renovation of old houses
(21) seismic reinforcement of lifeline buildings
(22) the shear wall shall be reinforced with circular holes under 1.6m and doors under 1000X 2000
(23) bridge fracture and old bridge maintenance and reinforcement
(24) improve the column bearing capacity to solve the column axial pressure ratio beyond the limit of reinforcement

6. Notes for pasting steel plates for reinforcement

Pasting steel plate reinforcement is a kind of common method of concrete structure reinforcement.
This method of work is relatively simple, it is necessary to master some basic points for attention in pasting and strengthening.

7. Requirements for pasting steel plates to reinforce concrete

For reinforced concrete structural members, the on-site measured concrete strength grade shall not be lower than C15, and the positive tensile bond strength of the concrete surface shall not be lower than 1.5mpa.
When pasting steel plates to reinforce reinforced concrete structural members, steel plates should be designed to bear only axial stress.

8. Pasting steel plate to reinforce fire prevention requirements

When the surface of reinforced members has fire protection requirements, according to the current national standard "fire code for architectural design" GB 50016 fireproof grade and fireproof limit requirements, the adhesive and steel plate for protection.

Key words: paste steel plate reinforcement bridge reinforcement bridge support replacement