The switch-back curve roads of open-pit mines are the key section which affects the transportation.In order to improve the road condition level of the switch-back curve roads and solve the damage problems of sags crests and track rut-deep,taking Hushan Uranium Mine in Namibia as the engineering background,the subgrade strength,pavement strength and superelevation setting of each switch-back curve road were calculated and verified respectively,and the corresponding management measures were put forward according to the production situation.The results show that the bearing capacity of calcium conglomerate subgrade on the surface is 1026.754 kPa,which is greater than its actual bearing of 825.0506 kPa,so there is no need to replace the calcium conglomerate subgrade.The pavement strength can be represented by the pavement thickness.Based on the truck types,traffic volume and road design of each road section as the basic input parameters,the minimum pavement thickness of the switch-back curve located on the pitheads of Z1S3,Z2S3 and the passageway of No.6 dump are respectively amended to 231.91 m,182.22 m,and 185.53 m,and the pavement thickness of switch-back curve located on the pithead of Z2S2 does not need to be adjusted.The superelevation,speed and turning radius at each switch-back curve should satisfy tana=v2/(Rg),and the speed should be remained at 10 km/h.The superelevation of the switch-back curve located on the heavy and empty lanes of Z1S3,the heavy lane of Z2S2,the heavy lane of Z2S3,and the heavy and empty lanes of No.6 dump are respectively amended to 2.4∶100,1.6∶100,2.7∶100,3.3∶100,1.6∶100,and 2.5∶100.The corresponding management measures have been put forward from three aspects:strengthening maintenance,regulating driving and standard shovel.The results have significantly improved transportation safety,service life,transportation efficiency and comprehensive costs of mine roads,and can provide a reference for the design optimization of switch-back curve roads of open-pit mines at home and abroad.
维普
万方数据