CE 3400 Chapter : Stresses
Document Summary
Consider a bar subjected to axial force p, with a cut taken perpendicular to its axis, exposing the internal cross- section of area a. The force per unit area acting normal to the cross-section is the stress. The symbol used for normal stress - the stress perpendicular to the material surface - is. The stress in an axially loaded bar is: Stress is positive in tension (p>0 means >0), and negative in compression (p<0). English units: psi (pounds per square inch), or ksi (kilopounds per square inch). S. i. units: pa (pascal, n/m2), or usually mpa (megapascal, 1 mpa = 1,000,000 pa). In addition to normal stress that is covered in the above section, shear stress is an important form of stress that needs to be understood and calculated. Most structures need to be designed for both normal and shear stress limits.
