一篇轧机是一种固有的不稳定的结构cture of large timber beams held together by self weight and compression joints. The potential failure mode was for one of these compression joints to become unloaded by high winds, allowing a beam to become dislodged. So the requirement was to monitor the joint loads, but inserting load cells was out of the question. The solution: put strain gauges on the compressed beams so they become their own load cells.
The talk covers the structure of the post mill and a basic force analysis showing the problem, the practicalities of using strain gauges on massive timber beams, calibration of the system, results obtained during a very windy night and the analysis that showed the mill is safe.

Dr Jack Hale - After 20 years in industries from coal mining to nuclear and a PhD developing ultrasonic non-destructive testing methods for glass reinforced plastics, he went to Newcastle University as a lecturer in mechanical engineering. There he conducted research in composite structures, piezoelectric strain sensor materials and the dynamics of engine timing chains, and taught elementary mechanics to 1^styears, more advanced dynamics to 4^thyears and design in between. He is now retired and lives in West Cumbria, but he maintains his association with Newcastle University as a Visiting Fellow and continues research on bio-mechanical structures.