Study on the Allowable Exposure Time of Temporary Goaf in the Open Stope and Backfill Mining Method with Large Structure Parameters

Table 2

Uniaxial creep statistics of the iron ore specimens.

Specimens	Stress level(% R)	Creep stress(MPa)	Predetermined load(kN)	Initial strain(%)	Final strain(%)	Creep strain(%)	Creep time(h)
Y2-6	50	81.80	153.88	0.23	0.247	0.017	192
Y2-7	60	98.15	184.93	0.27	0.291	0.021	192
Y2-8	70	114.51	216.82	0.32	0.348	0.028	192
Y2-9	80	130.87	247.59	0.36	0.483	0.123	175