If load P = 80 kN, find the reaction R(in kN) (correct to

If load P = 80 kN, find the reaction R(in kN) (correct to 1-decimal place) using elastic analysis.

Equating deflection at end R
Let l = 3 m

∴	R(l)³	=	P(1.5)³	+	P(1.5)²	× 1.5
	3EI		3EI		2EI

⇒	R(3)³	=	1.125P	+	1.6875P
	3EI		EI		EI

	9R	=	1.125P	+	1.6875P
	EI		EI		EI

⇒ R =	5	P
	16

or R =	5	× 80 = 25 kN
	16