The COHESIVE is a research group that combines two departments of the University of Nebraska - Lincoln. The Engineering Mechanics and Civil Engineering Departments are represented by Dr. David Allen and Dr. Yong-Rak Kim respectively. We have been working with experimental tests and computational models of crack growth and propagation on different types of medias since 2004. Our experimental and simulation laboratories are connected in a way that all the parameters measured in the experimental tests are used to develop and improve our computer codes. Using the interconnection between ours laboratories we predict how the behaviors of viscoelastic and viscoplastic solids are. With the combination of basic tools of fundamental mechanics, materials characterizations, problem solving techniques and computer codes development we use our multiscale code to solve real and complex problems such as roadways and tank armor subjected to impact loads. Based on and understanding the fracture mechanics of materials our main target of simulation is to predict the life time of these solids.