Design resistances of Blind Bolts

In order to verify the load carrying capabilities of blind bolts, a series of tests have been performed at the University of Manchester on M10, M20 and M24 bolts. This report details the testing and analysis of these bolts for design to both the British Standards and the Eurocodes.
A total of 77 tests were performed: 9 coupon tests to determine the material strength; 14 pure tension tests to determine the tensile resistance of the bolts; 15 pure shear tests to determine the shear resistance of the bolts; 18 combined tension and shear tests to validate the design equations in BS 5950-1 and BS EN 1993-1-8; and 21 bearing tests to establish the performance of the bolts in bearing. An analysis of each type of test was performed using the methodology in BS EN 1990, and a series of design rules, based on current practice for standard bolts, has been proposed. In general, these follow the current rules using modified areas as appropriate, except for the tensile resistance of blind bolts where a reduced strength, determined from the tests, is used. The test results also showed that the combined tension and shear equations in both BS 5950-1 and BS EN 1993-1-8 can be adopted for blind bolts.
A suggested presentation of the technical information for direct use by structural designers has been proposed in Appendix A. This report has been prepared by Mr Andy Smith and reviewed by Mr David Brown, both of the SCI.