in the name of allah

1. For NMAA and Kardan University Faculty of Engineering Lecture by : LT “Sayed Dawod karimi” dawodkarimi2007@gmail.com 0799560376 in the name of allah

2. 1. Learning Objectives • At the conclusion of this lecture you should be able to: • Recall the meaning and application of the terms “Stress and Strain.” • Recall the key portions of a stress vs. strain diagram. • Calculate average normal stress in a centrically axially loaded member. • Calculate average axial strain in a centrically axially loaded member. • Calculate average shearing stress on the transverse cross section of a bolt or pin. • Calculate average shearing strain in a body. Lesson #01Axial Loads – Stress and Strain

3. In order to properly design machines and structures, engineers must understand the effects that forces have on members. By quantifying these effects and understanding the engineering properties of the materials the members are made from, engineers can predict how members will perform. 2. Orientation

4. 4.1, 4.2, 4.4 3. Reading Assignment

5. Stress: A measure of the intensity of force. Expressed in units of Force/Area Strain: A measure of the intensity of deformation. Expressed in units of Length/Length Centrically Axially Loaded Member: A structural member subjected only to loads acting through the member’s centroid along its longitudinal axis. Normal Stress: The stress calculated using the component of the internal force in a member that acts normal to an exposed surface or cross section. Shearing Stress: Stress calculated using the component of the internal force that acts parallel to the exposed surface. Average Axial Strain: A measure of deformation over the length of a body. Axial strain is calculated by dividing the change in length over the body’s original length. 4. Key Definitions

6. 4.1, 4.2, 4.9, 4.36, 4.37 5. Study Problems

7. 4.14, 4.15 6. Challenge Problems

8. End of lesson Question