Civil and Environmental Engineering 2221A/B Lecture Notes - Lecture 16: Virtual Work

• School: Western University
• Department: Civil and Environmental Engineering
• Course: Civil and Environmental Engineering 2221A/B
• Professor: Wenxing Zhou

Document Summary

There is limitations o n the deflections calculations based on the conservation of energy principle: Only one load can be applied to the structure. Only the deflection at the location of the load application can be calculated. So, let"s look at something to beat these limitations. Lecture notes page 1 the virtual external work done by the virtual external forces on the real external displacement the virtual internal work done by the virtual internal forces on the real internal displacement. It will be more clear with an example. What we do is apply "virtual loads" apply before the structure is subjected to any real loads. This is following on the principle we were looking at in "important principle" last lecture. Load f is gradually increased to a maximum of p. p which causes a displacement . The virtual force p1 would do virtual work on the displacement caused by the real force (the force applied after) 1.