09-05-2012, 10:58 AM
Beams
BEAMS THEORY.pdf (Size: 614.51 KB / Downloads: 99)
Introduction to Beams
• A beam is a
horizontal structural
member used to
support loads
• Beams are used to
support the roof and
floors in buildings
Beam Theory
• Consider a simply supported beam of
length, L. The cross section is
rectangular, with width, b, and depth, h.
Beam Theory
• An area has a centroid, which is similar to a center of
gravity of a solid body.
• The centroid of a symmetric cross section can be easily
found by inspection. X and Y axes intersect at the
centroid of a symmetric cross section, as shown on the
rectangular cross section.
Modulus of elasticity, E, is a property that indicates the
stiffness and rigidity of the beam material. For example,
steel has a much larger modulus of elasticity than wood.
Values of E for many materials are readily available in
tables in textbooks. Some common values are