Effects of geometry on the deformation of asphaltic plug joints subjected to surface tractions

Asphaltic plug joints are widely used for accommodating structural movement in motorway bridges. In spite of their simplicity and low cost, these join ts suffer premature failure, of which debonding at the asphaltic plug/pavem ent interface is an important mode. In this paper, fundamental studies of t he debonding are carried out by means of detailed stress analysis. The asph altic plug is assumed to be viscoelastic while the pavement is assumed to b e linear elastic. Stress solutions are obtained using the finite clement me thod for a range of joint angles between the asphaltic plug and the pavemen t. The traffic loads are simulated using surface tractions applied in the v icinity of an interface corner on the wearing surface. The results show tha t the interface may experience stress reversal as the surface traction move s from one side of the interface corner to the other. Further, the magnitud es of the interfacial stresses decrease as the joint angle is increased fro m the current value of 0 degrees to about 45 degrees, thereby reducing the likelihood of debonding.