1.Jacks: there are two types of jacks:
B. Multi strands jack: in the bridge where tendons consist of a large number of strands it is impracticable to use mono strand jack because it will take longer time and it will increase the probability of strands trapping. So, in this case, we stress all strands in each tendon one-time using multi-strand jack. 
Jack calibration: jacks shall be calibrated periodically. Calibration for jacks is very important because the pressure recorded by jack own gauge is different from actual. So in this calibration shall be done to acquire correction factor. 
2. Master gauge: gauge shall be attached to jacks to measure accurate reading of jacks pressure. It shall be calibrated periodically. 
construction management: concrete construction
bridge construction:How to become a bridge engineer
