(1) the tension control stress of prestressed reinforcement shall comply with the design requirements. Need extremely when the construction of prestressed tensioning or included in the loss of prestress anchor ring mouth, comparable to the design requirement increased by 5%, but in any case shall not exceed the maximum tension control stress of the design rules. (2) of the prestressed steel by adopting the method of stress control tensioning, should check in elongation, actual elongation value and the difference of the theoretical elongation value should be controlled within 6%, otherwise should suspend tension, to find out the reason and take measures shall be adjusted and may continue to tension. (3) theoretical elongation value of prestressed steel delta L (mm) can be calculated by type (12.8.3-1) : type: Pp - the average tension of prestressed reinforcement (N), linear muscle tension of the tension, tensioning on both ends of the curve, calculation method of appendix G - 8; L - the length of the prestressed reinforcement (mm); AP - prestressed concrete cross section area (was); The elastic modulus of EP - prestressed (N/was). (4) the pull, the prestressed tendon should be adjusted to stress the delta 0 at the beginning of the appropriate initial stress for the tension control stress of the delta com 10% ~ 15%, the elongation value should be start when the initial stress measurement. Force the actual elongation value in addition to the measurement of the elongation value, must be combined with initial stress calculation under the elongation value. Components of post-tensioned method, in the process of tensioned value produced by the elastic compression can be omitted. Prestressed tensioning delta L (mm), the actual elongation value calculated by type (12.8.3-2) : delta L = delta L1 + delta L2 (12.8.3-2) : in the delta L1 - from between initial stress and the maximum tension stress measured elongation (mm); Delta L2 - under initial stress calculated elongation (mm), can use elongation value of the adjacent level. (5) when necessary, to deal with the anchor ring and friction loss are measured, the channel mouth when the tensioning shall be adjusted. (6) prestressed anchorage, should be in tension control stress under steady state. Prestressed anchorage stage tensioning end the drop-off in should not greater than the design rules or permissible value listed is not greater than standard