Define the meaning of circular prestressing
In circular prestressing, tendon wires are wrapped under tension over the concrete pipes which are pre-cast. The tension in the tendon wires is produced by pulling it through a die. Prestressed concrete pipes are ideally suited for a pressure range of 0.5 to 2 N/mm2. For this pressure range, cast iron pipes and steel pipes are not economical. Reinforced concrete pipes also are not practicable for use as these have limited tensile strength.