Shear Performance and Bearing Capacity Analysis at the Interface of Friction-Type High-Strength Bolted Joints for Aluminum Alloy-Stainless Steel Composite Plates

To investigate the interface shear performance of the novel aluminum alloy-stainless steel composite plate friction-type high-strength bolted joints， four groups of specimens were designed. Several parameters were considered， including the presence of interfacial particles， particle number， diameter-to-pitch ratio， and stainless steel plate thickness. Static loading tests were conducted to examine the effects of these parameters on the anti-slip coefficient and shear capacity. The results showed that the BASE specimens （with stainless steel particles at the interface） exhibited significant improvements over the ORIGIN specimens （without stainless steel particles） in terms of slip load， peak load， ductility， and stiffness. Specifically， as the number of stainless steel particles increased from 0 to 2， 4， 6， and 8， the slip load increased by 61.7%-81.9% and the peak load by 7.5%-12.7%. The effects of the diameter-to-pitch ratio and plate thickness were also examined. Four specimen groups with diameter-to-pitch ratios of 0， 2/8， 2/6， and 3/8 were tested， yielding slip load increases of 69.2%-97.8% and peak load increases of 10.38%-23.5%. Regarding plate thickness， increasing the thickness from 3 mm to 5 mm improved the slip load and peak load by 14.6% and 9.5%， respectively； a further increase from 5 mm to 8 mm led to enhancements of 17.2% and 12.1%， respectively. When the bolt preload was 15 kN， the maximum increase in slip load reached 13.1%. In addition， for composite plates with edge margins of 10， 15， 20， and 25 mm， the slip load and peak load increased by 39%-63.8% and 37.3%-54.4%， respectively. Based on these findings， a calculation formula for the shear capacity of this novel particle-reinforced friction-type high-strength bolted joint was proposed and validated， providing a reference for practical engineering applications.