Effects of Cover Plate Stiffness on Load Distribution of Bearing-Type Multi-Row Bolted Connections for FRP Composite Structures

Abstract

The present study investigates the effect of different thicknesses of steel and fiber reinforced polymer (FRP) cover plates on the mechanical behavior of bearing-type multi-row bolted connections for FRP composite structures. Connections with a double-lap configuration up to four rows of bolts subjected to tensile loads have been studied numerically. These numerical data are examined in detail to understand the effects of cover plate stiffness on load distributions among rows of bolts. The study also considers the influence of geometric parameters on the load distributions. For validation of the connection model, numerical results are compared with experimental results available in literature. The results show that the load distribution in bearing-type multi-row bolted connections is significantly affected by the cover plate stiffness. A connection with higher cover plate stiffness tends to show lower efficiency. For a connection with steel cover plates, to increase number of bolt rows more than three does not lead to a higher capacity of a connection. The results also indicate that effect of geometric parameters on the load distribution is not significant with change of cover plate stiffness.