Experimental Study on the Transition between Static and Kinetic Frictions of Steel/Shale Pairs

Table 2

Mechanical parameters and plasticity index of steel/shale specimens.

Mechanical parameter	Steel ball	Shale 1#	Shale 2#	Shale 3#
E (GPa)	190		44.41
	0.305		0.24
(GPa)	1.0097		2.64
()	0.28	0.693	0.944	0.622
R ()	20	12	8	12
	4.51	3.50	5.00	3.32