Sometimes when your calcium/magnesium ratio is off, you can get twitching. I get one in my diaphram that feels like a fish flopping in my chest. If you are low in calcium intake, or very low in magnesium, the muscles do a dance of sorts. So you could try to balance that out.
(February 2017) A concrete slab is a common structural element of modern buildings. Horizontal slabs of steel reinforced concrete, typically between 4 and 20 inches (100 and 500 millimeters) thick, are most often used to construct floors and ceilings, while thinner slabs are also used for exterior paving.
Finishing the Basement Floor. When building slab foundations, the concrete pour comes after the footings have set and before walls are erected. Dirt is compacted and backfilled with four to six inches of gravel. Typically, a six-mil polyethylene sheet provides a vapor barrier between the soil and the slab.