| Summary: | 碩士 === 國立交通大學 === 土木工程系所 === 107 === This research explore the application of thermal sprayed coating to slip-critical joints to increase the slip coefficient and confirm the slip-critical joints with coating satisfying the creep requirements. The experiment consisted of two sequence tests of slip test and tension creep test. The slip test used to investigate the influence of the coating material and coating thickness on the slip coefficient. The tension creep test was conducted by applied the load calculated based on the slip coefficient, and recorded the slip due to the creep of the coating under a long-term load of 1000 hours. The specimens comprised two splice plates with thermal sprayed coating and a main blasted plate, jointed by a high-strength bolt F10T. The slip test results showed that using pure aluminum or aluminum-magnesium alloy sprayed coating, the slip coefficients could reach 0.82 to 0.94, with an average of 0.88 that was 1.6 times or more than the specified slip coefficient of 0.50 for Class B coating on blast-cleaned steel. The thickness of the coating had no significant effect on the slip coefficient, but as the thickness of the coating increased, the bolt pretension loss increased. The test results of the tension creep test showed that significant creep behavior was observed during the first 100 hours of the test, and the slip during this period was about 80% of the total slip. Specimens with thermal sprayed either pure aluminum or aluminum-magnesium alloy with 150 μm coating thickness, under the design load calculated by a slip coefficient of 0.60, can meet the requirements of the tension creep test. In this research, the application of the thermal sprayed aluminum alloy to the slip-critical joint can increase the slip coefficient and enhance the connection resistance that can be used in engineering practice.
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