computational contact mechanics

Dear All,

As FEA is one of the most popular methods for the treatment of contact problems. In that, the overall contact surface is discretized a number of segments and contact integrals are evaluated in a segment-wise manner. In 2005 Fischer and Wriggers [1] presented an integration method which avoids the need of contact surface segmentations and enables the evaluation of contact integrals directly at the slave nodes of contact bodies. 

I am modelling a very simple 2D contact problem between a rigid wedge indenter and a deformable squared-shape specimen (general steel material) in frictionless contact case. I used an implicit function f to describe the rigid indenter.

I implemented Lagrange multiplier method for this contact problem and the contact condition is: Inside the contact zone of the deformable specimen, the node set is active if f(node)<=0 and the Lagrange multiplier lambda<=0.

I am modelling a very simple 2D contact problem between a rigid indenter and a deformable squared-shape specimen. I used a implicit function f to describe the rigid indenter. 
The contact condition is: Inside the contact zone of the deformable specimen, a node n is outside of rigid indenter for f(n)>0, and inside for f(n)<0. In case f(n)=0, the contacting node lies on the surface of the rigid body.