I want to use a element that has stiffness as well as friction between concrete and bar.so i use axial connectors.for d11 value in elastic property i use stiffness.coefficient of friction can also be given.but i am confused with internal contact force value.how to calculate it???.please help.and do we nee to channge the orientation of the axis by giving a 90 degree rotation about y axis so that the axis of the of connector gets aligned to x axis.??Actually the i am using the connector in vertical direction that means a y axis on global coordinate system.thats mean do we need to do that rotation with ref to global so that the vertical direction becomes x axis for connector??