We started our project last Feb then rains hit and there were more delays with problems with the grotto design the. We added a spa and that took more delays so our rebar sat. Today we had an inspection for the spa pipes and the inspector did not like the rusty rebar. My PB said he was going to get a letter from the engineer that using the rusty rebar was fine. Is it? Is it going to give me trouble down the line? What a disaster! Replace all of that would be impossible as they’d have to redo the whole grotto and I’m not paying for it!
Rusty Rebar
- Thread starter Speechteacher
- Start date
- Jul 21, 2013
- 53,677
- Pool Size
- 35000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-60
Can you show us pics of what the rebar looks like?
Let's see what @AQUA~HOLICS thinks about an Inspector rejecting rusty rebar.
Let's see what @AQUA~HOLICS thinks about an Inspector rejecting rusty rebar.
Rust on rebar is allowed due to the fact that it’s going to be incapsulated inside the Shotcrete.
I have run into this issue before and made a call in front of the inspector to the Steel Engineering firm who wet stamped the plans and had them explain to the inspector in greater detail about the ASTM specifications requirements.
It becomes a concern when the weight of the rebar is reduced and/ or the deformation height is reduced.
I have run into this issue before and made a call in front of the inspector to the Steel Engineering firm who wet stamped the plans and had them explain to the inspector in greater detail about the ASTM specifications requirements.
It becomes a concern when the weight of the rebar is reduced and/ or the deformation height is reduced.
Last edited:
- Jul 21, 2013
- 53,677
- Pool Size
- 35000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-60
If the rebar is properly encapsulated with at least 3 inches of gunite then rebar stains should not surface.
Reinforcing bars used in structural concrete has raised deformations on it, which helps keep the reinforcing bars locked inside the concrete.
Special care needs to be taken to make sure the reinforcing bars are clean of any debris (such as caked-on mud or rust) to allow them to function properly.
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Q.: If reinforcing bars have been stored outside and have a coating of rust, how much rust is acceptable?
A.: Section 12 of ASTM A 615-96a, "Standard Specification for Deformed and Plain Billet Steel Bars for Concrete Reinforcement," says that rust shall not be cause for rejection provided the weight, dimensions, cross-sectional area, and tensile properties of a hand-wire-brushed test specimen aren't less than the ASTM specification requires.
Section 7.4.2 of ACI 318-95, "Building Code Requirements for Structural Concrete," has a similar statement indicating that reinforcement with rust shall be considered satisfactory, provided the minimum dimensions (including height of deformations) and weight of a hand-wire-brushed test specimen aren't less than applicable ASTM specification requirements.
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CAN YOU USE RUSTY REBAR IN CONCRETE?
It’s perfectly fine using “rusty” rebar that is coated in mill-scale and is not genuinely rusted. Mill-scale has even been shown to improve the adhesion between rebar and concrete.
Section 12 of the ASTM A 615-96a, “Standard Specification for Deformed and Plain Billet Steel Bars for Concrete Reinforcement,” states explicitly that rust is not a cause to reject a piece of rebar so long as it otherwise meets ASTM specifications.
When Rusty Rebar Can Become Problematic
Given certain conditions, rusty rebar can be an issue.
First, the rebar must be exposed to corrosive elements. Perhaps the concrete around the rebar has cracked, and saltwater has made its way to the exposed steel. Road salt and seawater can provide enough chloride ions. However, that steel rebar can be affected even if the concrete remains whole.
Corroding steel presents a couple of problems. First, the more steel rusts, the weaker it becomes as the metal is replaced by flakes and powder. Second, rusting steel expands.
As the steel expands, it places more stress on the surrounding concrete in a process called “oxide jacking.” This process causes the concrete to fail faster than it would have otherwise.
www.dwreinforcing.com
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Generally speaking, rust on your reinforcing steel isn't a problem where it's formed by fresh water and research has demonstrated that a light coating of rust may actually help to increase the bond with concrete. The Australian Standard makes this clear:
AS 3600, Clause 19.2.4 states: “At the time concrete is placed, the surface condition of reinforcement shall be such as not to impair its bond to the concrete or its performance in the member. The presence of millscale or surface rust shall not be cause for rejection of reinforcement under this Clause.”
When rust might be a problem
There are a few instances where rusting of reinforcing steel may create structural or aesthetic issues:
Rain may wash rust off reinforcing steel laid in formwork such that it stains visible concrete. In this instance, the SRIA recommends removing loose rusted material prior to pouring your concrete or for more significant applications, using galvanised steel
Salt water can cause a more serious corrosion issue that may render the rebar or mesh structurally unsuitable. Where you have reinforcing steel that's been subjected to salt water and has visible rust it is important to treat it by using high-pressure washing to remove salt and loose corrosion and in severe cases the steel may need to be replaced. If in doubt, conduct strength and cross-sectional area limitation tests.
www.materialslink.com.au
_______________________________________________________________________________________________________________________
Special care needs to be taken to make sure the reinforcing bars are clean of any debris (such as caked-on mud or rust) to allow them to function properly.
_______________________________________________________________________________________________________________________
Q.: If reinforcing bars have been stored outside and have a coating of rust, how much rust is acceptable?
A.: Section 12 of ASTM A 615-96a, "Standard Specification for Deformed and Plain Billet Steel Bars for Concrete Reinforcement," says that rust shall not be cause for rejection provided the weight, dimensions, cross-sectional area, and tensile properties of a hand-wire-brushed test specimen aren't less than the ASTM specification requires.
Section 7.4.2 of ACI 318-95, "Building Code Requirements for Structural Concrete," has a similar statement indicating that reinforcement with rust shall be considered satisfactory, provided the minimum dimensions (including height of deformations) and weight of a hand-wire-brushed test specimen aren't less than applicable ASTM specification requirements.
_______________________________________________________________________________________________________________________
CAN YOU USE RUSTY REBAR IN CONCRETE?
It’s perfectly fine using “rusty” rebar that is coated in mill-scale and is not genuinely rusted. Mill-scale has even been shown to improve the adhesion between rebar and concrete.
Section 12 of the ASTM A 615-96a, “Standard Specification for Deformed and Plain Billet Steel Bars for Concrete Reinforcement,” states explicitly that rust is not a cause to reject a piece of rebar so long as it otherwise meets ASTM specifications.
When Rusty Rebar Can Become Problematic
Given certain conditions, rusty rebar can be an issue.
First, the rebar must be exposed to corrosive elements. Perhaps the concrete around the rebar has cracked, and saltwater has made its way to the exposed steel. Road salt and seawater can provide enough chloride ions. However, that steel rebar can be affected even if the concrete remains whole.
Corroding steel presents a couple of problems. First, the more steel rusts, the weaker it becomes as the metal is replaced by flakes and powder. Second, rusting steel expands.
As the steel expands, it places more stress on the surrounding concrete in a process called “oxide jacking.” This process causes the concrete to fail faster than it would have otherwise.
Is Rust a Problem on Rebar?
Rusty rebar might seem like a problem since rust usually indicates the metal is being weakened by corrosion, but it's not always an issue.
www.dwreinforcing.com
_______________________________________________________________________________________________________________________
Generally speaking, rust on your reinforcing steel isn't a problem where it's formed by fresh water and research has demonstrated that a light coating of rust may actually help to increase the bond with concrete. The Australian Standard makes this clear:
AS 3600, Clause 19.2.4 states: “At the time concrete is placed, the surface condition of reinforcement shall be such as not to impair its bond to the concrete or its performance in the member. The presence of millscale or surface rust shall not be cause for rejection of reinforcement under this Clause.”
When rust might be a problem
There are a few instances where rusting of reinforcing steel may create structural or aesthetic issues:
Rain may wash rust off reinforcing steel laid in formwork such that it stains visible concrete. In this instance, the SRIA recommends removing loose rusted material prior to pouring your concrete or for more significant applications, using galvanised steel
Salt water can cause a more serious corrosion issue that may render the rebar or mesh structurally unsuitable. Where you have reinforcing steel that's been subjected to salt water and has visible rust it is important to treat it by using high-pressure washing to remove salt and loose corrosion and in severe cases the steel may need to be replaced. If in doubt, conduct strength and cross-sectional area limitation tests.
Rusty Rebar—Is It A Problem?
Reinforcing bar and mesh often arrives on site with some rust on it. This is quite normal: hot-rolled bars and coil have a layer of what's called mill-scale on the surface when they leave the mill. This mill-scale provides a protective layer in the right conditions but if stored externally or if...
www.materialslink.com.au
_______________________________________________________________________________________________________________________
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This is all excellent information. I have found a lot of this on the web in my searches, but I guess I need a bottom line: The rebar was installed then we had 6 weeks of rain. We had a lot of water in the pool then vegetation grew and needed to be cleaned out. Then the grotto needed to be finished and by then the rebar was already coated in rust. It’s been sitting now for 10 months. PB wants me to pay $ 5-7 thousand to replace it or I have to live with it. He is not aware of any abatement coatings so he won’t guarantee the shell if they are used. I’m not as concerned about structural integrity as I am about rust stains leaching through to the finish. Their engineers quoted similar findings to what you quoted. I bought my own wire brushes and will see if I can clean off more than their team did (which would mean they didn’t clean it at all). I am going to try to call a few local pool companies on Monday for advice. I will meet with the city inspector when he comes. I HATE this pool, it’s been nothing but headaches and the company is Crud, PB is so bad at planning and management, but seems like decent workmanship from the crews.Reinforcing bars used in structural concrete has raised deformations on it, which helps keep the reinforcing bars locked inside the concrete.
Special care needs to be taken to make sure the reinforcing bars are clean of any debris (such as caked-on mud or rust) to allow them to function properly.
View attachment 543037
_______________________________________________________________________________________________________________________
Q.: If reinforcing bars have been stored outside and have a coating of rust, how much rust is acceptable?
A.: Section 12 of ASTM A 615-96a, "Standard Specification for Deformed and Plain Billet Steel Bars for Concrete Reinforcement," says that rust shall not be cause for rejection provided the weight, dimensions, cross-sectional area, and tensile properties of a hand-wire-brushed test specimen aren't less than the ASTM specification requires.
Section 7.4.2 of ACI 318-95, "Building Code Requirements for Structural Concrete," has a similar statement indicating that reinforcement with rust shall be considered satisfactory, provided the minimum dimensions (including height of deformations) and weight of a hand-wire-brushed test specimen aren't less than applicable ASTM specification requirements.
_______________________________________________________________________________________________________________________
CAN YOU USE RUSTY REBAR IN CONCRETE?
It’s perfectly fine using “rusty” rebar that is coated in mill-scale and is not genuinely rusted. Mill-scale has even been shown to improve the adhesion between rebar and concrete.
Section 12 of the ASTM A 615-96a, “Standard Specification for Deformed and Plain Billet Steel Bars for Concrete Reinforcement,” states explicitly that rust is not a cause to reject a piece of rebar so long as it otherwise meets ASTM specifications.
When Rusty Rebar Can Become Problematic
Given certain conditions, rusty rebar can be an issue.
First, the rebar must be exposed to corrosive elements. Perhaps the concrete around the rebar has cracked, and saltwater has made its way to the exposed steel. Road salt and seawater can provide enough chloride ions. However, that steel rebar can be affected even if the concrete remains whole.
Corroding steel presents a couple of problems. First, the more steel rusts, the weaker it becomes as the metal is replaced by flakes and powder. Second, rusting steel expands.
As the steel expands, it places more stress on the surrounding concrete in a process called “oxide jacking.” This process causes the concrete to fail faster than it would have otherwise.
Is Rust a Problem on Rebar?
Rusty rebar might seem like a problem since rust usually indicates the metal is being weakened by corrosion, but it's not always an issue.
_______________________________________________________________________________________________________________________
Generally speaking, rust on your reinforcing steel isn't a problem where it's formed by fresh water and research has demonstrated that a light coating of rust may actually help to increase the bond with concrete. The Australian Standard makes this clear:
AS 3600, Clause 19.2.4 states: “At the time concrete is placed, the surface condition of reinforcement shall be such as not to impair its bond to the concrete or its performance in the member. The presence of millscale or surface rust shall not be cause for rejection of reinforcement under this Clause.”
When rust might be a problem
There are a few instances where rusting of reinforcing steel may create structural or aesthetic issues:
Rain may wash rust off reinforcing steel laid in formwork such that it stains visible concrete. In this instance, the SRIA recommends removing loose rusted material prior to pouring your concrete or for more significant applications, using galvanised steel
Salt water can cause a more serious corrosion issue that may render the rebar or mesh structurally unsuitable. Where you have reinforcing steel that's been subjected to salt water and has visible rust it is important to treat it by using high-pressure washing to remove salt and loose corrosion and in severe cases the steel may need to be replaced. If in doubt, conduct strength and cross-sectional area limitation tests.
Rusty Rebar—Is It A Problem?
Reinforcing bar and mesh often arrives on site with some rust on it. This is quite normal: hot-rolled bars and coil have a layer of what's called mill-scale on the surface when they leave the mill. This mill-scale provides a protective layer in the right conditions but if stored externally or if...
_______________________________________________________________________________________________________________________
What about rust leaching through the finish causing stains? That’s my biggest concern. Seems like removing stains requires removing the rebar which in this case is the whole thing. PB wants to charge $5000-7000 to redo rebar.
The picture you provided shows what appears to be typical surface rust, common practice to have this level of rust on the rebar with no bleeding from the cage.
Bleeding from the cage occurs with a constant water exposure from a crack allowing the rust to make its way to the surface, not from previous rust incapsulated properly within the Shotcrete.
Bleeding from the cage occurs with a constant water exposure from a crack allowing the rust to make its way to the surface, not from previous rust incapsulated properly within the Shotcrete.