Problem 4

Abstract

Analyze the truss described in Problem 1 (Figures 1.1 and 1.2) subjected to two different loading conditions. First, apply a thermal load by raising the temperature of the six GRIDs of the structure as follows:

$$ {{\rm{T}}_1} = {{\rm{T}}_{\rm{2}}} = {{\rm{T}}_3} = {{\rm{T}}_{\rm{4}}} = 60^\circ {\rm{F}} $$

((4.1))

and

$$ {{\rm{T}}_5} = {{\rm{T}}_{\rm{6}}} = 200^\circ {\rm{F}} $$

((4.2))

Use a thermal expansion coefficient (α) of 6.3x10^-6 in/in °F and assume that the reference temperature (the temperature at which the structure is free of thermal stresses) is 20 °F. Second, determine the reaction of the structure if ROD number 100 is subjected to an axial elongation of.05 in.