10.3 Main Technical Standard of Railway Line
10.3.1 Locomotives and wagons of standard-gauge railway shall be categorized in accordance with the following requirements:
1 When the fixed wheelbase of locomotive is no more than 2.6m and total wheelbase is less than 11m，and fixed wheelbase of ore wagon is no more than 1.8m and total wheelbase is less than 11m，the locomotive and wagon shall be categorized as CategoryⅠ.
2 When the fixed wheelbase of locomotive is no more than 2.6m and total wheelbase is no less than 11m but less than 16m，and fixed wheelbase of ore wagon is no more than 1.8m and total wheelbase is less than 11m，the locomotive and wagon shall be categorized as CategoryⅡ.
3 For the renovated and extended mine，if the fixed wheelbase of reused locomotive is more than 2.6m but less than 3m，and fixed wheelbase of ore wagon is no more than 1.8m and total wheelbase is less than 11m，the locomotive and wagon may comply with the CategoryⅡstandard.
4 When the fixed wheelbase of ore wagon is 1.2m×2 and total wheelbase is less than 13m，the locomotive and wagon shall be categorized as CategoryⅢ.
10.3.2 The minimum radius of plane curve of railway line within standard-gauge railway sections shall be in accordance with those specified in Table 10.3.2.
Table 10.3.2 Minimum radius of plane curve of railway line within standard-gauge track sections（m）
Note:Value in bracket is the allowable value for circular moveable line in the mining field.
10.3.3 The minimum radius of plane curve of standard-gauge railway connecting line may comply with the standard for ClassⅢsemi-fixed railway line as stipulated in Table 10.3.2.
10.3.4 In the area with restricted terrain conditions，the minimum radius of plane curve of standardgauge railway line may comply with the following requirements:
1 ClassⅡandⅢfixed line may be subject to the standard for semi-fixed line of the same class.
2 ClassⅡsemi-fixed line may be subject to the standard for ClassⅢsemi-fixed line.
10.3.5 Where an old standard-gauge railway line undergoes renovation or a second line is added，the radius of curve may be non-integral.In the areas with restricted terrain condition，the minimu radius of plane curve may be determined after comparison with the old line condition.
10.3.6 The minimum radius of plane curve of narrow-gauge railway line shall be in accordance with the following requirements:
1 Complying with those specified in Table 10.3.6.
Table 10.3.6 Minimum radius of plane curve of narrow-gauge railway line（m）
Table 10.3.6（Continued）
2 In the areas with particularly difficult conditions，the minimum radius of plane curve of narrowgauge railway line may comply with the following requirements:
1）The minimum curve radius of ClassⅠandⅡrailway line may be subject to the standards one class inferior to those specified in Table 10.3.6.
2）The minimum curve radius of initial subgrade of ClassⅢrailway line and moveable line shall not be less than 15 times of fixed wheelbase for 600mm gauge railway，and not less than 25 times of fixed wheelbase for 762mm/900mm gauge railway.
10.3.7 Maximum grade of section line and connecting line of standard-gauge railway shall not be larger than those specified in Table 10.3.7.
Table 10.3.7 Maximum grade of section line and connecting line of standard-gauge railway（‰）
10.3.8 Maximum grade of narrow-gauge railway shall not be larger than those specified in Table 10.3.8.
Table 10.3.8 Maximum grade of narrow-gauge railway（‰）
10.3.9 Width of subgrade surface of single track standard-gauge railway at straight section shall be in accordance with the following requirements:
1 As per those specified in Table 10.3.9.
Table 10.3.9 Width of subgrade surface of single-track standard-gauge railway at straight section（m）
2 The distance from centerline of standard-gauge railway in the cutting along bottom level of the sleeper to side slopes of cutting shall not be less than 3.5m on one side and 2.8m on the other.
3 As for the ClassⅢfixed line of which the transport volume exceeds 2Mt/a，width of nonpermeable soil subgrade surface shall be 10 cm more than those specified in Table 10.3.9.
10.3.10 Width of subgrade surface of single fixed line narrow-gauge railway at straight section shall be in accordance with those specified in Table 10.3.10.
Table 10.3.10 Width of subgrade surface of single fixed line narrow-gauge railway at straight section（m）
10.3.11 For track type selection of the standard-gauge railway，the following requirements shall be complied with when the axle load of locomotive and wagon is 25t or less:
1 Track type of standard-gauge railway section lines shall be selected in accordance with those specified in Table 10.3.11.
Table 10.3.11 Track type of standard-gauge railway section lines
Table 10.3.11（Continued）
2 Track type of connecting line and station line may be selected in accordance with standard for ClassⅢrailway line specified in Table 10.3.11.
3 For empty-wagon-traveling line of double-track railway，the steel track should be of the same type as for loaded-wagon-traveling line，whereas the number of sleepers may be 80 pcs/km or 160 pcs/km less compared with those specified in Table 10.3.11，however，the number of sleepers shall in no case be less than 1520pcs/km.
4 If curve radius of railway line for CategoryⅠwagon is less than 150m，that for CategoryⅡwagon is less than 180m，and that for CategoryⅢwagon is less than 200m，the number of sleepers in curve area shall be 80pcs/km more than those specified in Table 10.3.11，however，the number of sleepers shall in no case exceed 1760pcs/km.
5 Track bed of moveable line shall be filled，leveled and compacted by using materials available at site.Thickness of track bed shall not be less than 15cm.
6 Thickness of track bed in the switch area shall not be less than that of track bed of the railway line connected to the said switch.
7 As for the ClassⅢfixed line of which the transport volume exceeds 2Mt/a，thickness of track bed on the non-permeable soil subgrade shall be 5 cm more than those specified in Table 10.3.11.
8 When the axle load of locomotive is 28t，number of concrete sleeper shall be 1760pcs/km，and thickness of track bed shall not be less than 35cm.
10.3.12 Track type of the narrow-gauge railway may be selected according to those specified in Table 10.3.12 and meanwhile shall be in accordance with tthe following requirements:
1 As for the moveable line，its steel tracks shall be selected in accordance with the criteria for tracks of main line to which it is connected，and the number of wooden sleepers shall be 80pcs/km-100pcs/km more than those required in the criteria for tracks of main line to which it is connected.When there is no track bed，the subgrade shall be filled，leveled and compacted by using materials avialbe at site.
2 Track type of all railway lines other than main line，station line and moveable line shall be selected according to the criteria for tracks of station line to which the said line is connected.
Table 10.3.12 Track type of narrow-gauge railway
Note:As for length of each link of steel track on which the calculation of number of sleeper is based，it is 12.5m if the track is heavier than 24kg/m，and 10m in all other cases.For the railway line with staggered joints or laid with steel tracks shorter than standard length（each link），the number of sleepers per kilometer may be incrased appropriately.