Has anyone actually tried to repair such column smashed down to the core. Lol.
If anyone does. How did you do it especially when it was the ground floor column of a 50 storey building? Just curious.
The problem with chipping it is how do you replace the small removed concrete with the same strength as the original and binding to the remaining or rest of the concrete?
Imagine there is huge moment to the right and the neutral axis is toward the right. Even if you plug cement or small...
This is the original structural plan the owner gave me:
The column (blue arrow) is carrying a 5.4 meters long big beam carrying the house balcony and another beam perpendicular to it.
Just wondering. In your design. What do you do when the column is exterior and exposed to rain all the time...
But the ties are distant 8 inches apart. So how do I find where the ties would intersect the vertical crack? maybe with a metal detector? What kind of metal detector could pinpoint the ties so accurately?
And it would even be more difficult to find cracks that would intersect the longitudinal...
The carbon fiber wrap would be circumferential to serve as replacement for the spiral ties. When you guys mentioned the rebar corroding. Do you mean the longitudinal rebars or the spiral ties?
When you mentioned "BUT if there is ongoing corrosion, and you do NOT encapsulate the column...
Ok. I used a digital caliper meter to measure the gap. It's about 0.35mm crack gap.
If I chip into the rebar. This would result:
Imagine the column is bending to the right and there is a chipped area (in red), the concrete radius would be like 6" - 1.5" = 4.5 inches only instead of 6...
The hairline crack is only 0.05mm thickness (thickness of a paper).
Minimum thickness before one can inject epoxy resin must be at least 0.1mm
The column is only 1 foot across, I can't chip further without damaging it and decreasing the axial or bending capacity.
So if you can't inject epoxy...
We chipped off the surface, the crack is in the concrete and not the coating. See:
It is NOT even 1mm wide, just paper thin hairline crack.. how do you inject epoxy resin in paper thin gap? If not possible, how do you fix it?
What if I chip 1/4 inch.. then 1/2 inch.. then 1 inch or 3 inches or more to inside.. then a lot of concrete would be lost.
To put carbon fiber to it. The surface simply has to be finished to smooth texture so the epoxy can hold.
I don't want to chip the render or concrete as the whole column is only 1 foot diameter. Here is zoom of it. It doesn't look like just the render because the crack is discontinuous so unlikely.
Supposed the crack is up to deep inside. What kind of failure mode would occur. It's not a shear or...
The coastal is miles away.
It is exposed to rain. Can rain water get inside the hairline crack?
Our area is a seismic zone. Can any further seismic activity open it up so carbon fiber wrap around it is required? I think wrapping it with carbon fiber can totally prevent any spalling making it...
This round column measuring 12 inches diameter (0.3 meter) has 8 pcs of 20mm rebar with 10mm spiral ties spaced 8 inches (0.20 meter) apart.
There is a vertical hairline cracks measuring about 1 meter. I'd like to know the following:
1. Usually what caused the vertical hairline crack?
2...
