Under resilient floors, what is less likely to telegraph joints after moisture equilibration: semirigid epoxy or polyurea?
We are using a concrete mix with 60% slag in architectural concrete and are having significant issues with the color of the concrete. What can we do to avoid this?
-
Besides changing the color, does adding pigment to concrete have any other effects on its properties that a contractor should be aware of?
-
Under what conditions are we allowed to retemper ready-mixed concrete at the jobsite? If we receive a batch that has too low a slump, can we add water to make the concrete more workable?
-
Do I need to cut completely through a slab to form isolation joints?
-
Are joints in concrete meant to accommodate expansion or contraction? Someone told me that what I've always called expansion joints I should now call contraction joints. Does this mean that concrete doesn't expand? What are these joints actually supposed to do?
-
We've been asked to place a concrete pad as the floor for a newhome, on a base of crushed limestone. There will be copper water pipescoming up through the floor. Are there any reasons for concern about a chemical reaction between the limestone and the copper pipe?
-
We have our first large self-consolidating concrete (SCC) project coming up soon, so I want to ensure that we get this right. The engineer performed the required test mixes to confirm slump, flow, spread, and compressive strength performance. The mix from
-
The contractor says it is a workmanship problem between me and the excavator. What are your thoughts on this and how should I go about repairing it? The contractor suggested pumping grout under the floor at the joints, but I don't think that is a good ide
-
I am the building manager for a large church on the East Coast. We recently have contracted with a company to grind and overlay about 5000 square feet of our church.
-
I am the building manager for a large church on the East Coast. We recently have contracted with a company to grind and overlay about 5000 square feet of our church.
-
A lot of the concrete we're now placing would be considered “low slump.” Years ago it would have meant trouble for the crew. But today, we're able to work with most of the low slump concrete we get. Is the slump test outdated?
-
I am about to install a 10,000-square-foot floor and the owner believes that wet curing the floor will result in no curling. Is this true?
-
Q: I'm fairly new in the concrete business and I know that a mix's water-cement ratio affects how well the concrete turns out, but as a contractor why should I care about something called "aggregate moisture?"
-
Questions about the effects on curing of temperature and superplasticizers.
-
I am a concrete contractor in the Southwest and to beat the heat in the summertime, I cast my slabs early in the morning, starting before dawn. By avoiding the heat of the day, doesn't this reduce the need for curing?
-
What tests can I use to determine if the curing has been effective?
-
I am using a superplasticizer in my concrete. I have heard that since this is a water-reducer, the need for curing water is reduced. Is this correct?
-
I have a project specification that requires fog spraying, followed by curing compound, followed by wet cure with burlap and soaker hoses. Why the complicated curing requirements? Isn't this a case of specification-overkill?
-
I was told that what we used to call expansion joints I should now call contraction joints. Does that mean that concrete doesn't expand?