What is the Final Word for Rebar Conc Slab on Grade, Steel Structure Mrzzanine?

Rest assured: Any 1st cost savings will be repaid @ 10 000% w/ later headaches.

DON'T BE "CHEAP", be frugal.

Why are you compacting the aggregate, added the sand for chinking and the vapor barrier all this will do is trap water under causing you trouble down the road? Why only 10 cm of concrete? It should be at least 15.25 cm to support the weight.

My suggestion 15.25 cm-20.33cm of 2.5 cm aggregate (un-compacted) with the wire mesh on rockers with at least 15.25 cm concrete Class AA (ACI).

My take in original query is that it is an 'inside a building' floor, will be used as a foundation for 'some sort of UNDEFINED machine tool'.

The compaction steps i'd consider mandatory, to prevent settling later. The vapor barrier would be to prevent moisture from infiltrating into the shop space (rusting, &al)

In the overall scheme of things preparation & concrete are small costs; overbuild! Tomorrow you WILL need more.

What's off topic? I guess getting an opinion from someone who's done this kind of work for 14 years is to much for some people.

Coming from someone who wants to put down a gravel pit and railroad ties I will take this a a complement.

I guarantee that what ever industrial equipment he puts down isn't going to move it you put on 6 inches of 1" stone and 6-8 inches of concrete with wire and fiber. It's a common practice over here in PA for road construction or other industrial sites, plus PA has a wide varied of soil times. If this is to be placed on a concrete floor you can easily tie it in by drilling in rebar apply an epoxy that will allow the old concrete to adhere to the new concrete add you wire mesh and fibers and your set. If they want to rip up the old concrete flooring and lay down a new section soil what be an issue because the area is pretty much compacted from before add you stone and concrete as stated above and away you go.

10 cm or 4" thick slab seems very thin for a factory. That's the thickness of a sidewalk! The waking sounds like a vibratory roller. That would be a big mistake on some soils. 4" of stone is usually good, but the choking with sand is used to "tightenup" the base. If the soils underneath are bad enough that you need more strength from the stone base make it thicker. It probably the manpower that is the most costly part. Besides all that, the vapor barrier is now full of holes from "whacking" it with all of that sharp stone.

Since you are using a walk behind roller, this suggests to me that you are working in a confined space such as under a roof. if you used a finer stone such as #8, 0r #9 (pea size gravel) you would not need to compact it. Also the chairs for the rebar is a good thing, but most of the time the concrete guys step on it and press it to the bottom where it does no good. They hate using it.

If I were doing this I might (depending on the geotechnical engineer's recommendations), use the following:

compacted subgrade, 4" (10 cm) of #8 stone, vapor barrier, 5" of 4000 psi concrete with fiber reinforcement and not rebar/ mesh.

Dear all

Thanks for your valuable time, Please read below and comment?

http://www.cement.org/tech/faq_fibers.asp

Below is what in http://www.cement.org/tech/faq_fibers.asp for your quick review

Frequently Asked Questions
Cement & Concrete Technology Home > FAQs > Fibers

Q: Can fibers replace wire mesh or welded wire fabric in a concrete slab on ground?

A: To answer this question, it is first necessary to establish why wire mesh or fibers would be used in a concrete slab. One of the main reasons is for crack control. PCA, however, states that cracks in slabs on ground can be controlled with uniform subgrade support and proper joint spacing (as a function of slab thickness). See Table 6-3 from PCA's Concrete Floors on Ground (EB075).

Table 6-3. Reinforcement for Floors on Ground

Although short joint spacings alleviate the need for reinforcement, wire mesh will allow for increased distance between joints if correctly placed in the upper portion of the slab, at least 2 in. below the surface. In these slabs with longer joint spacings, the purpose of wire mesh is to hold random intermediate cracks tight.

Plastic fibers should not be expected to replace wire mesh in a slab on ground. However, although not affecting joint spacing, plastic fibers are used to reduce plastic shrinkage cracking.

Plastic shrinkage cracks are those that occur immediately following concrete placement, before the concrete has hardened. Plastic fibers are commonly dosed at 0.1% by volume for slabs on grade; this is equivalent to 0.9 kg/m³ (1.5 lb/yd³). Polypropylene fibers are among the most common for controlling plastic shrinkage cracking. There are many types of fibers in addition to polypropylene, including other plastic materials, such as nylon. Fibers serve different purposes based on the characteristics of the material from which they are made. For instance, steel fibers provide high flexural strengths and impact resistance and are found in heavy-duty industrial floors.

For additional information on fibers for use in concrete, see Fibers(IS532) and Fiber Reinforced Concrete (SP039)

I need more infromation about wire mesh on rocker

10 cm, that is like 4 inches. 10 cm is nothing, someplaces end up with 10 feet of aggregate base rock underneath and entire facility. This is thinner than many commercial concrete driveways (about like a residential driveway or sidewalk with reinforcement, except the aggregate thickness is a little thin). The cost of materials is probably about as cheap as you are going to get for any marginally effective support. Though i guess you could do just about anything if you were willing to pay the repairs to maintain the equipment within balance and alignment requirements every so often. How much would it cost you to take this 10 ton equipment off line for a few days and move it to do repairs every few weeks or so?