摘要:
An erect cylindrical pressure vessel, especially for a nuclear reactor, is constituted from cast-iron or cast-steel elements and is stressed by axially extending angularly spaced axial stressing elements and by axially circumferential peripheral stressing elements or cables. At least one of the axially stressing cables and at least one of the peripheral stressing cables serving for sustaining the operating load of the pressure vessel, i.e. the working elements rather than the addition or additional elements, is provided with a measuring device which triggers an alarm upon the detection of a change in the force developed at the respective stressing element or the length change thereof reaching 90% of the corresponding change at the pressure rating of the vessel.
摘要:
In the post-stressing of concrete structures, a tendon comprised of a plurality of elongated strands is formed by inserting elongated strands which will eventually form the tendon into a plurality of parking ducts and then withdrawing the plurality of strands simultaneously as a group from the parking ducts and into the duct of the structure to be post-stressed without fouling and jamming. Once in the ducts of the structure, the strands are anchored and post-tensioned as a tendon to develop the desired stress.
摘要:
A novel jacking system and method are provided for moving a cable through a sheath which includes opposite vertical portions connected by an intermediate arcuate portion. The cable is relatively heavy, being made up of the order of some 170 to 200 strands of high carbon steel wire, each approximately of the order of one-quarter inch in diameter. The total length of the cable is of the order of 500 feet while its weight is some 7-1/2 to 10 tons.
摘要:
A nuclear reactor pressure vessel comprising a concrete vessel wall, stressing tendons passing through said concrete wall and thereby pre-stressing said concrete, pods provided in said wall for accommodating heat exchanger tube banks, each pod extending to the outer surface of the wall, and a closure member closing each of said pods, each of said closure members being held in position by means of some of said stressing tendons.
摘要:
A method of preparing parallel-wire cable for use in prestressed concrete pressure tanks comprises the steps of cutting the cable in lengths with each wire of equal length, twisting the lengths of cable at least twice about the longitudinal axis of the cable, and preferably from two to five times, and positioning the lengths of cable within the tank wall prior to stressing the cable. The cable is preferably twisted before it is placed in position in the tank. However, it may be twisted after insertion into passageways within the concrete wall of the tank.
摘要:
A pressure container is wound with special bands of wires in superposed groups and the wires are prestressed and clamped to the container by means of superposed axial strips on the container with radial bolts engaging the walls of the container.
摘要:
A PRESTRESSED PRESSURE VESSEL HAVING AN OPENING IN ONE OF ITS EXTERNAL SURFACE TO THE INTERIOR THEREOF, THE VESSEL BEING PRESTRESSED BY A PLURALITY OF PRESTRESSING CABLES EXTENDING THROUGH THE MATERIAL OF THE VESSEL SUBSTANTIALLY PERPENDICULAR TO THE ONE SURFACE. AT LEAST SOME OF THE PRESTRESSING CABLES ARE UTILIZED FOR MAINTAINING A REMOVABLE CLOSURE MEMBER OVER THE OPENING, THERE BEING MEANS FOR MAINTAINING AT LEAST SOME OF THE TENSION IN THESE CABLES WHEN THE CLOSURE MEMBER IS REMOVED SO THAT THEY STILL FUNCTION TO PRESTRESS THE VESSEL.