A screw includes a head part, a threaded part and a flexible connector between the head part and the threaded part for transmitting a torsional force between the head part and the threaded part, and to allow two bending movements between the head part and the threaded part in opposite directions in the longitudinal axis of the screw. The head part and the threaded part in each case have a longitudinal axis, which can be arranged offset in parallel to one another. The screw has an -modulus of between 20,000 and 100,000 N/mm.sup.2 against a rotation in the case of an arrangement of the head part and the threaded part on a longitudinal axis.

A system for tensioning a stud that projects from a structural member is provided. The system comprises a safety guard including a guard housing and a hydraulic interlock assembly, and a tensioning system coupled with a first end of the stud. The guard housing surrounds at least a portion of the tensioning system and is coupled with a second end of the stud and the hydraulic interlock assembly. The hydraulic interlock assembly is coupled with the guard housing and the tensioning system. The hydraulic interlock assembly provides fluid communication of a hydraulic fluid from a hydraulic source to the tensioning system to tension the stud.

A screw includes a head part, a threaded part and a flexible connector between the head part and the threaded part for transmitting a torsional force between the head part and the threaded part, and to allow two bending movements between the head part and the threaded part in the opposite direction in the longitudinal axis of the screw, wherein the head part and the threaded part in each case have a longitudinal axis, which can be arranged offset in parallel to one another, and wherein the screw has an -module of between 20,000 and 100,000 N/mm.sup.2 against a rotation in the case of an arrangement of the head part and the threaded part on a longitudinal axis.

A bolt tension gauging apparatus is provided with a bolt assembly including a bolt having a top cavity on a head and a recess on a surface of a threaded shank, and a covering element fitted onto the recess; an electrical resonant transformer on a bottom of the covering member; and a force transducer and transmitter assembly in the recess and electrically connected to the transformer. An electrical resonant transformation device causes the transformer to harvest power from radio frequency electromagnetic waves if a distance between the transformation device and the transformer is sufficiently short. The force transducer and transmitter assembly gauges tension of the bolt and converts same into a signal. The signal is transmitted to a controller and display device for calculating a difference between a predetermined tension and the gauged tension. An alert is generated if the gauged tension is greater than the predetermined tension.