Research conclusions : (1)The tensile value and measured anchorage rebound volume made from the method presented in this paper satisfy the requirements of stressed steel bar for manufacture and tension. ( 2 ) When the tension comes to the end, the measured outcome of top anchor degree conforms to that of design, so this method can be used for calculation and measurement of prestressed tensile of steel strand.(3)When the steel strand is tensioned for several times, the tensile volume of each time should be accumulated and when calculation of the tensile volume, the working length of the jack should be subtracted.