Civil Engineering Reference
In-Depth Information
P =K δ
(5.5.1A-1)
where:
P
is a vector of resultant prestress and applied nodal loads
K
is the stiffness matrix
δ
is a vector of nodal displacements
There are several ways to solve this set of simultaneous equations, either directly or
indirectly. For example, if we wish to analyze the effect of an applied load of 2.0 kN
on the prestressed three bar network shown in Figure 5-13.
Figure 5-13
Stiffness Example
(Drawing by the author)
In this example the supports at A, B & D provide translational but not rotational
restraint. The bars are steel, with equal areas.
Given:
A(0,1000)
B(0,-1000)
D(4000,0)
P
CX
=0.0 kN
P
CY
=2.0 kN
And:
A = 40 mm
2
for each bar
E =200 kPa (kN/mm
2
) for each bar
F
i
= 10.0 kN prestress in each bar
Find:
C
(XY)
The displacement of point C
F
i
The corresponding force in each bar
Search WWH ::
Custom Search