I have a concrete overflow out of one of my ponds that has a leak and I need to fix it. I've finally gotten the water level down low enough the leak has stopped so I can finally work on it.
The pond had 2 metal pipes with a 90 degree vertical bend in it, but that didn't flow well. I cut the 90 degree part off and then made a concrete box that funnels the water into the pipes and that has worked well for 2 years. This summer I let some grass take root right at the juncture of the metal pipe and the concrete and when the water finally got high enough to overflow it washed the grass away and I got a leak. Now I'm wondering what's the best way to patch this.
I can cap it by adding a 1-2" thick layer of concrete that tapers into the pipe or I can get the sledgehammer out and knock me some concrete out and repour a section, but would that give me an even greater area to leak?
What's the right way to do this? I've got a few days of warm weather coming so I'd rather do it sooner rather than later.
How would I use epoxy and what kind of epoxy?
It's a minor crack at the joint, but since the guy upstream of me has had a leak from day 1 it made me think this might get complicated
Mechanical engineer here so if a Civil Engineer is on here please speak up.
It sound as if the bond between the pipe and the concrete isn't strong enough. You have a band aid and then you have the do it right option.
They do make in water setting concrete which may be your best bet. If you can stop flow long enough to get the water level down I would do that and re pour the box. Look for ways to seal the concrete to the pipe. I think they do make epoxys for such jobs.
Good Luck
I have the water level down so that I can do anything, but repouring the box is out of the question - it's about 8' x 10'. Each pipe is 21" in diameter.
I was afraid I'd have to bust out the concrete right at the joint of the metal and the concrete thinking that possibly it was a thin spot.
Presuming I bust the concrete out how do I use an epoxy to seal the concrete to the pipe? I was concerned that if I busted the concrete out I'd create a much bigger joint that would make it leak even more.
Can you use hydraulic cement? The kind they pour underwater bridge abutments and dams out of. I have used it to make posts for a boat dock - but that was in standing water - no pressure flowing.
They make a material for use in cold joints in concrete that might work in your application. It swells when water touches it. If you could get enough access to put some in around the pipe and then re pour the area it might work. Epoxy or urethane injection seems like a better option to me though.
I'm not sure how well epoxy would bond to a steel pipe so maybe a hydrophobic would be better than hydrophilic because of it being constantly wet. How thick is the the concrete that the pipes run through?
What do you call the stuff that swells when wet and how would I install it.
How would I inject epoxy or urethane?
Are either of these things something I can get at Home Depot or Lowes?
I don't have to worry about wet ground during the install, well no wetter than when you dig down a ways. It's only when I refill the pond that the pressure will rise. Fortunately the pond is big enough that no matter how hard I work on filling it back up it will take a good rain storm to do the job for me and that probably won't happen till spring.
I don't think you can get anything at a big box store that would work for the size of the job you have. If your trying to push urethane past about twelve inches you really need a pump. It might not be the best route for a do it yourself type repair. But would be the most permanent in my opinion.
This
is similar to what we used but I really don't know where to get it. We got ours from a concrete supply house that stocked a lot of concrete repair materials. I've been out of that game for a while now so a lot of the brand names and names of business's that catered to what we did have slipped my mind.
Ohhhh, that's something I would have to break out, install and re pour. It's more of less a gasket.
Well if I have to break it out I'll definitely find something like that. I have some concrete houses within driving distance that I can get stuff from. It's just that I have the big box stores just down the street. I'll do whatever I have to do.
I'll try to explain a little about epoxy or urethane injection.
The whole goal is to completely fill the gap with whatever your using. I'll say urethane because I believe it will give you the best shot at a more permanent repair. If the thickness of the concrete is around twelve inches or less you can use a low pressure gun to push the material in the crack. The hydrophobic urethane we used would expand around 400% it's volume and is activated when it comes into contact with moisture. Around a pipe I would place an injection port at the very bottom and then about ten inches apart all the way around. Then seal the entire crack around the pipe with a fast setting epoxy paste. once the paste has set, usually about a half hour depending on temp, start injecting at the bottom and keep pushing until it starts to come out of the next port. If you have access to the other side you could wait to see if it came all the way through before moving up. If not cap the one your working on and keep moving up and around until there all filled. The gun is around two hundred bucks and the materials aren't cheap either. If your going into something thicker you'll need a high pressure set up either air or electric to pump it all the way through and those are really, really expensive.
Epoxy does not do good with water, everything has to be completely dry or you will not have good results. If there is a little moisture present it will retard the cure. A lot of moister and it will never cure and just become a gel and water will just push it through. Of course once it's cured it will act almost like a weld.
I would look into a real good urethane sealant such as NP1 and seal the joint all the way around, then cover that with some kind of membrane like this or this
.
why does a pond need pipes and cement?
novaderrik wrote:
why does a pond need pipes and cement?
To manage overflow when the rains come. If we didn't have pipes and cement soon we'd have a creek bed that is lower than the pond level.
Giant Purple Snorklewacker wrote:
Streetwiseguy wrote:
Hydraulic cement?
Like this... for use underwater or to fix leaks
WOW! The spec sheet on that seems to indicate this will work like a patch. I'm betting it's available at a big box store too.
I'm going to have to try that first.
"All patch areas should be free of loose material, dirt, dust, algae and mildew. Preparation should include enlarging small cracks and holes and avoiding V-shape cuts.
Starting at the top and working down, apply Water-Stop Cement while maintaining light pressure on the patch. Maintain pressure until initial set begins and the leaking is stopped."
carguy123 wrote:
Giant Purple Snorklewacker wrote:
Streetwiseguy wrote:
Hydraulic cement?
Like this... for use underwater or to fix leaks
I'm betting it's available at a big box store too.
It is, unless you've just had 5 inches of rain. Then it will take them a week to restock.
dmyntti
New Reader
11/22/10 12:08 p.m.
In building construction we use what is called a linkseal at building penetrations where pipe goes thru a wall. We build gas compressor stations so we deal with this often. Below is a link to the type we use. I would give them a call and see what tyoe of pressure they can handle.
http://www.linkseal.com/htmlPages/index.html
As I cleaned up the leaking area I found out that there was a thin area just by the pipe. It appears that a too large rock was in the cement mix and it got knocked out which left a week spot.
I found the hydraulic cement at Lowes - Sakrete brand. While it says it will set in 3-4 minutes it actually has a life of under a minute. That was heLL to work with. You've seen the quick setting cement in cartoons where they set the guys feet in cement and it hardens with a ZING! Well, this is it!
By the time I got to the last little bit I mixed it very thin and poured it down the side trying to give it somewhat of a smooth finish and as it ran down the sides it went from super thin to a frozen standing wave in about a foot.
I used 20# on one side and now I need to buy some more and do the other side. It wasn't leaking but why wait?
Second half of the job went much faster and much easier than the 1st half. So here are some SAGE WORDS OF WISDOM.
1) I used the Quickcrete brand. It gave me a working time of 2-3 minutes whereas the Sakrete brand gave me a working time of 2-3 seconds.
2) This time I knew to mix it much thinner than you would normal concrete Not soup, but a little thinner than pancake batter.
3) Mix quickly and just as in baking muffins -ignore the lumps. You can't get them out with the short amount of time you have to work the mixture. Definitely try to get the biggest out, but there will be a lot of little ones left. You can trowel them out on the job.
Fortunately my job was a low place at the bottom so I could just pour the mix down the sides and let it settle in the bottom. That gave me a nice level job.
If you were patching something on a wall or other vertical surface I'd say GET A HELPER! Have one person mixing small batches and handing them over to the dauber. Think of a mud dauber and how he gets his house together. That's how you'll have to do this.
You would mix it thicker than pancake batter. You still need it so that it's too loose to the eye because this stuff sets up so quickly that if you don't you will have no working time at all.
I had to patch a spot towards the top of the pipe and I dribbled the loose stuff in the hole and by the time I did a couple of dribbles I had a clay like mixture left to stuff in the hole. Within seconds of becoming a clay like mixture it becomes hard, dry and brittle so don't dally! Trowel quickly unless you like the rough primitive look.
Now on to the brick clothes hamper in the bathroom and the finish mortar work on the stone window surrounds. I WILL have all this through before company comes tomorrow if it kills me!
