Engineering Classification of Jointed Rock Mass Based on Connectional Expectation: A Case Study for Songta Dam Site, China

Table 1

A list of influencing factors considered in typical rock mass classification methods.

Method	RSR	RMR	Q	Z	YZP	ET	China national standard	Number of factors
Proposed age	1972	1973	1974	1979	1985	1985	1994
Number of joint sets			√					1
Joint spacing	√	√	√		√	√	√	6
Joint state	√	√	√		√	√	√	6
RQD		√	√		√	√	√	5
Rock mass structure				√				1
Integrity		√		√	√	√	√	5
Weathering					√	√	√	3
In situ stress			√			√	√	3
Groundwater	√	√	√		√	√	√	6
Geological structure	√							1
Rock strength	√	√	√	√	√	√	√	7
Joint shear strength				√	√	√		3
Rock mass deformation modulus					√	√		2
Rock deformation model					√			1
Rock mass elastic wave velocity				√	√		√	3
Rock wave velocity			√	√	√	√	√	5
Joint orientation	√	√		√	√		√	5
Construction method				√				1
Classification grade	5 grades	5 grades	9 grades	5 grades	5 grades	5 grades	5 grades
Engineering application	Tunnel support	Tunnel mining	Tunnel cavern	Dam foundation of underground engineering	Rock mass of dam foundation	Rock mass of dam foundation	Underground and ground slope