I know certain types of cinders are used to make concrete block. Anyone know if cinders are used anywhere as a road base instead of limerock or stone? STUMP KNOCKER
are you talking about slag from a steel mill if you are the local mill crushes and sells it the small size is extremely heavy so less volume per ton and the larger sizes is lite er than stone but it is full of air pockets and crumbles easy under traffic.
I think the term "cinder block" is mostly outdated. Modern CMU's are made of crushed stone. However a local asphalt plant has been incorporating slag waste from the steel mills into some of their mixes. The EPA has changed several rules on foundry "waste", the in's and out's I don't know but it has changed the classification and disposal of certain foundry wastes.
Cinders from a coal fired power plant.
The town I grew up in spread cinders as traction material during the winter instead of sand.
The EPA has ruled on coal ash as well - http://www.epa.gov/wastes/nonhaz/industrial/special/fossil/ccr-rule/ccrfaq.htm#16
Ah-ha - Pulverized Fuel Ash or PFA as 'tis known on the eastern side of the pond. AFAIK it's still widely used in concrete and construction.
Same here, called fly-ash. Commonly used as a filler in redi-mix. A couple of weeks ago we ordered a pneumatic tanker full of flue dust to dry up a very wet site and meet compaction requirements. The flue dust is the waste from the cement kilns, it's grey in nature and is similar to regular powdered cement. It's purpose is to suck the moisture out of the soil and physically change the fatty clay present, in this case it was a very wet clay/chert. Worked like a charm and we obtained compaction specs, once we mixed into the existing fill lift - hell on machines though.
PFA was commonly used as fill in between concrete retaining walls for bridge ramps at one time. Not sure if this is still the case.
In the "old days", cinders were used to make lighter weight concrete block. The cinders could replace both fine and coarse aggregate,( sand and Crushed stone), which is heavy. The resulting concrete block was called "cinder block", or "lightweight block". This lightweight block, today, is generally made with "lightweight aggregate" replacing the cinders of the old days. Lightweight aggregate is clay or shale that is burned in a rotary kiln at high temps. This forms a "clinker" like material that is then crushed and screened to make the proper size aggregate, depending on the use. It is kind of like crushed up bricks, except the kiln temps are not nearly as high as those used when making brick. Another common use of lightweight aggregate is on road resurfacing. They call it a 'chip and seal coating" in this area. That is where an asphalt liquid is sprayed on the highway, toped with a light dusting of lightweight aggregate, and rolled into place with a rubber tired roller. This will extend the life of asphalt pavement. The aggregate topping keeps the surface from being really slippery and keeps vehicles from tracking the liquid asphalt everywhere while it is curing out. The lightweight aggregate is used so when car tires pick the stuff up and throw it, it will not break windshields of oncoming vehicles. When they use crushed stone for this coating, it often will break ar windshields.