Risk Assessment of Water and Sand Inrush in Mining under Thick Loose Layer Based on Comprehensive Weight-Cloud Model

Table 1

Risk grade interval of water and sand inrush risk assessment index.

Index	Risk grade interval
	I	II	III
(m)	0~15	15~30	>30
(-)	0~1	1~3	>3
(m)	>10	5~10	0~5
(m)	0~3.5	3.5~8	>8
(%)	80~100	60~80	0~60
(-)	0~0.4	0.4~0.6	0.6~1.0
(m)	>40	20~40	0~20