A propped cantilever beam is subjected to a point load, P at its mid span as shown in figure. The load P is gradually increased to a certain value till the formation of plastic hinge at fixed support only. What would be the additional increment in load is required at its midpoint so that a complete collapse mechanism is formed in the propped cantilever beam, where Mp is the plastic moment carrying capacity of section.
1
\(\frac{{16{M_p}}}{{3L}}\)
2
\(\frac{{6\;{M_p}}}{L}\)
3
\(\frac{{2{M_p}}}{{3L}}\)
4
\(\frac{{\;{M_p}}}{{3L}}\)