Nothing Special   »   [go: up one dir, main page]

Load Classification A. According To Time: Concentrated Load Distributed Load

Download as docx, pdf, or txt
Download as docx, pdf, or txt
You are on page 1of 4

Introduction

Strength of materials extends the study of forces that was begun in Engineering
Mechanics, but there is a sharp distinction between the two subjects. Fundamentally, the field of
mechanics covers the relations between forces acting on rigid bodies; in statics, the bodies are in
equilibrium, whereas in dynamics, they are accelerated but can be put in equilibrium by applying
correctly placed inertia forces.

Three Basic Types of Loading (Load Classification)


1. Simple axial load = A force with its resultant passing through the centroid of a particular
section and being perpendicular to the plane of the section. 
2. Twisting load
3. Bending load

LOAD CLASSIFICATION

A. According to Time

1. Static Load - gradual application of loads for which


equilibrium is achieved at a very short time.

2. Sustained Load - load that is constant over a long period of


time

3. Impact Load - impulsive and rapid application of loads

4. Repeated Load - successive application and removal of


loads

B. According to Distribution

1. Concentrated Load - point load

2. Distributed Load - a load distributed along a line or a


surface.
Distributed Load
Concentrated Load
C. According to Location and Method of Application

1. Centric Load - load that pass through the centroid of the


resisting section.

2. Torsional Load - load that twists a member

3. Flexural / Bending Load - load that is applied transversely to


the longitudinal axis of the member.

4. Combined Loading - any combination of the first 3 above.


REACTIONS and INTERNAL FORCES

Reactions - surface forces that develop at the supports or points of


contact between bodies.

Cable

R
Roller

R
Hinge x
R
y

Rx
Fixed M
R
Equations of Equilibrium y

⮚ General Force System

∑ Fx = 0 ∑ Mx = 0

∑ Fy = 0 ∑ My = 0

∑ Fz = 0 ∑ Mz = 0
⮚ Coplanar Force System

∑ Fx = 0

∑ Fy = 0

∑ Mp = 0

⮚ Concurrent Force System

∑ Fx = 0

∑ Fy = 0

Internal forces - forces developed within the body of a


member due to application of external loads.

You might also like