# Strength of materials

Principle axis The following are the terms basic to the study of mechanics, which should be understood clearly. The quantity of the matter possessed by a body is called mass. The mass of a body will not change unless the body is damaged and part of it is physically separated.

Fine a sub-grouping of the members that are either purely in series or in parallel, and use the equations provided to calculate the equivalent stiffness, force and deflection in Strength of materials sub-group. The sub-group can then be considered a single spring with the calculated stiffness, force, and deflection, and that spring can then be considered as a part of another sub-group of springs.

Continue grouping members and solving until the desired result is achieved. Stress Concentrations Forces and stresses can be thought to flow through a material, as shown in the figure below. When the geometry of the material changes, the flow lines move closer together or farther apart to accommodate.

If there is a discontinuity in the material such as a hole or a notch, the stress must flow around the discontinuity, and the flow lines will pack together in the vicinity of that discontinuity. This sudden packing together of the flow lines causes the stress to spike up -- this peak stress is called a stress concentration.

The feature that causes the stress concentration is called a stress riser. Check out our interactive plots for common stress concentration factors.

Stress concentrations are accounted for by stress concentration factors. To find the actual stress in the viscinity of a discontinuity, calculate the nominal stress in that area and then scale it up by the appropriate stress concentration factor: When calculating the nominal stress, use the maximum value of stress in that area.

For example, in the figure above, the smallest area at the base of the fillet should be used. Many reference handbooks contain tables and curves of stress concentration factors for various geometries. MechaniCalc also provides a collection of interactive plots for common stress concentration factors.

The concentration of stress will dissipate as we move away from the stress riser. Calculation of stress concentration is particularly important when the materials are very brittle, or when there is only a single load path.

In ductile materials, local yielding will allow for stresses to be redistributed and will reduce the stress around the riser. For this reason, stress concentration factors are not typically applied to structural members made of ductile materials.

Stress concentration factors are also not typically applied when there is a redundant load path, in which case yielding of one member will allow for redistribution of forces to the members on the other load paths. An example of this is a pattern of bolts. If one bolt starts to give, then the other bolts in the pattern will take more of the load.

Combined Stresses At any point in a loaded material, a general state of stress can be described by three normal stresses one in each direction and six shear stresses two in each direction:subjects home.

contents chapter previous next prep find. contents: strength of materials chapter introduction to mechanics of deformable bodies. chapter axial force, shear and bending moment.

chapter stress. chapter strain. chapter stress and strain relations. chapter stress and strain properties at a point. The strength of a material can refer to yield strength, ultimate strength, or fracture strength. Tensile strength can be calculated from hardness and is convenient because hardness tests—such as Rockwell—are usually simple to do, inexpensive, and nondestructive.

Strength of Materials widely relies on the Theoretical Mechanics, Mathematics and Physics.

## Strength of Materials, 2ed: regardbouddhiste.com: Debabrata Nag, Abhijit Chanda: Books

Besides, it is the basis of the other subjects in the engineering practice. BASIC PROBLEM OF THE STRENGTH OF MATERIALS The basic problem of the science is development of engineering methods to . In materials science, the study of this subject 'strength of a material' is the ability of a material to withstand an applied load without failure or plastic deformation.

The field of strength of materials deals with forces and deformations that result from their acting on a material. To give an ability to apply the knowledge of strength of materials on engineering applications and design problems.

Course Material: Text Book is “ Mechanics of Materials, 6 th Edition Beer, Johnston, DeWolf, McGraw-Hill, , ISBN ”. Science at Home: Strength of Materials Trisha April 4, Science, Science at Home Science at Home is a new video series that I will be co-hosting every .

Strength of materials - Wikipedia