1. How to deal with the basis reinforcement interface?
Based on old concrete surface using artificial chiseling, washed with water and dust, mixed with interfacial agent cement after pouring concrete for galling.
2. How to deal with the brick wall reinforcement interface?
The brick wall is reinforced by shotcrete, with a thickness of 100px and 175px. On the surface of the original decorative layer should be removed clean, mortar application blade or wire brush to smooth surface is not easy to clean up the carefully cleaned, and then rinse with water cannons. Paste the hair with cement paste and water for 1~3 days (depending on the wetting degree of the surface). The old brick drying fast water absorption, to prevent dehydration of mortar powder, reach a certain strength, should advance 24h water wetting wall galling for 1~2 hours before watering again, the brick wall should eat depth of more than 25mm, and to strengthen the maintenance can achieve the ideal effect.
Reinforcement of interface processing quality, directly affect the reinforcement effect, if Konggu, off, "two skin" and other quality problems, related to the safety of the structure transformation. In the process of construction, the drug should be treated, the treatment is strengthened, and the interface treatment is controlled as a special process.
3. How to handle the frame column reinforcement interface?
1). example: for example, after on-site investigation and inspection, after the demolition of the decoration surface, there are tiny cracks on the surface of the columns, which are about 5 ~ 25mm deep, the carbonation depth of concrete is close to 20mm, the surface concrete is crisp and has the phenomenon of pulverization, while some columns have large vertical deviation. By agreement with the design, testing and other units, that just cut hair or hair treatment agent interface is not up to the requirements, determine the concrete surface meeting.
First determine the carbonation of concrete surface layer, the artificial tick chisel off the surface of the concrete layer of 5 ~ 15mm with large deviation to the local tick protection layer can be exposed the dust, stirrups, loose place flush with water cannons, a new crop clean, compact, reinforcement.
2). in the detection of section II and V, it was found that the frame column was strengthened in 80s, and the thickness of the section method was increased by the outer wrapped reinforced concrete. The thickness was about 375px. During drilling and core sampling, it was found that the interface treatment was not good at the original reinforcement, and the surface of the joint was mixed with sawdust, dust and other matters, forming a "two layer skin" phenomenon. In some places, the old and new concrete was not bonded at all. It is considered that the whole reinforcement should be removed. But the demolition is difficult and inefficient. At the same time, too much demolition vibration will have adverse effects on the structure.
The pillars are arranged around the "shear pin", make the interface between new and old concrete on the shear stress borne by the steel that hit the depth 625px, with diamond Phi 36 holes, with plastic anchor Phi 25 short ribs, short vertical spacing of the reinforcement @500, pay attention to drilling should be avoided during their main reinforcement (using reinforced steel position detector to determine).
3. How to deal with the interface of beam and plate reinforcement?
Most of the beams and plates are reinforced by the use of carbon fiber (locally used carbon fiber). The interface processing: electric grinder Polish 2 ~ 3mm steel plate surface, blown with the hair dryer, and then dipped in acetone can be brushed cotton silk; the less dense concrete, hollowing, hole and other places shall be removed to dense, with high strength grouting material to repair the flat, can stick steel.