This is the unified translation term in Arabic

English term (edited): pre-stressed concrete units

Pre-stressing: Placing steel wires, which are under tension, inside the material to compress the parts that would otherwise be in tension. The wires can be tensioned before or after the concrete is poured - hence the names pre-tensioning and post-tensioning. Allowance has to made made for creep, in setting the tension. The tension needs to be such that under maximum design load, the concrete is never stretched past its original length.