kas pie velna ir "prestressed concrete"? kas tas par betonu? nevienā vārdnīcā tāda nav...

maybe no šī var izlobīt kādu domu... es nevarēju... sevišķi mani interesē tās daļas kas ir boldā
"generally, in the original conception prestressed concrete was prestressed only if under the working load the stresses were entirely compressive, that is, nowhere should the concrete be in tension under design load conditions. but conditions at ultimate load were ignored. still, a few engineers accepted an intermediate condition that is concrete which was precompressed but where small tensile stresses were permitted."