Study of strain energy based shear model for single lap bolt

In simplifying large numbers of bolt connections in simulation to substitute the construction of the whole joint structure, it is essential to establish a joint constitutive model. In this paper, a shear constitutive model of the single lap bolt was established. Firstly, the curves of the load-displacement of the single lap shear bolt were obtained from experiments, and the corresponding physical mechanism was analyzed using the finite-element method. Then, the curve of the load-displacement was divided into several phases according to the physical mechanism. Based on the first three phases, the basic form of the shear constitutive model was proposed and the related parameters were determined in detail. In the second phase of the shear model, the support stiffness was solved by the strain energy method based on reasonable stress distribution hypothesis, which was a step most difficult to take. Finally, this constitutive model was verified by numerous examples. The results show that this shear model for the single lap bolt has the advantages of providing clear physical meaning, easy parameter estimation, and high accuracy.