Introduction

Structural Analysis courses and textbooks generally focus on linear structural behavior. A structure that behaves linearly exhibits a straight-line relationship between load and deflection. For example, a structure that deflects 0.1 inch subjected to an applied load of 10 kips will deflect 0.20 inches when the load is increased to 20 kips. This linear relationship continues until the structure either undergoes plastic deformation and or fails. It is important to note, that linear behavior requires that two fundamental conditions be met.