creator Dally, James W. A bolt having a shank and integral head has a strip of photoelastic material mounted on the head for manifesting in the form of photoelastic fringes linearly related to bolt tension the bending stresses created in the head during loading of the bolt. To determine the tension in the bolt during or after loading, polarized light is directed toward the photoelastic strip and reflected light from the strip is analyzed to measure fringe order. The fringe order is related to the amount of bending stresses in the head of the bolt by a predetermined calibration curve, the bending stresses being linearly related to bolt tension. Submitted by Aric Ahrens (ahrens@iit.edu) on 2011-11-09T16:55:22Z No. of bitstreams: 1 3718066.pdf: 349669 bytes, checksum: dd9c0392bc90ddc867dbd56f2c6d17ef (MD5) Made available in DSpace on 2011-11-09T16:55:22Z (GMT). No. of bitstreams: 1 3718066.pdf: 349669 bytes, checksum: dd9c0392bc90ddc867dbd56f2c6d17ef (MD5) Previous issue date: 1973-02-27 IIT Research Institute 2009-04-30 1973-02-27 3,718,066 http://hdl.handle.net/10560/2302 en United States Patent Patent reformatted digital application/pdf No Copyright - United States http://rightsstatements.org/page/NoC-US/1.0/ Open Access