Design the length of steel strand sometimes not included in the tensioning length, or is computation stretching length does not match with the actual, so in the construction calculation of steel wires length and tension prestressed reinforcement length shall be adjusted according to the actual situation, according to the measured one thousand jins crest length, anchor ring thickness adjustment. Under normal circumstances, the prestressing tendons pull length should be to calculate the position of the jack tool anchor, steel wire feeding length should also in length of prestressed tendons based on each end and Jack tool anchor 20cm strand tendon length.

Section area (A) and elastic modulus (E) of prestressing tendons

Design and calculation of non cohesive steel strand of the theoretical value of elongation of the cross-sectional area and modulus of elasticity is the provisions of the standard value, but to enter the construction site of the steel wires cross-section area and elastic modulus and standard value there are some deviations, so we should according to each batch of steel strand measured cross-sectional area and modulus of elasticity on Calculation of theoretical elongation value is corrected.