水保所知识产出(1956---)知识库

露天矿排土场平台径流汇集量大且急促，常导致边坡发生强烈沟蚀。排土场平台-
边坡系统集中来水条件下的侵蚀过程研究仍十分薄弱。本研究以平台-边坡系统为对象，采
用野外放水冲刷试验方法，研究不同放水流量(48、60、72、84 L·min
－1
)下系统径流、产沙及侵
蚀形态演变规律。结果表明: 48 L·min
－1
流量时，平台-边坡系统以细沟侵蚀为主，60 ～ 84
L·min
－1
流量下系统发育形成切沟。平台、边坡流速随放水历时呈突变-波动-稳定变化趋势，
平台流速小于边坡径流流速，减幅为 8．3% ～67．1%，边坡流速为边坡上/下部最大，较中部增
加 18．5%～44．6%。平台和边坡产沙率随放水历时呈现突变-波动-稳定 3 个阶段，边坡产沙率
高达平台的 17．4 倍;平台上细沟侵蚀产沙量占比高达 86．6%～95．1%，60～84 L·min
－1
流量下
边坡切沟侵蚀产沙量占比高达 69．2% ～86．6%。平台侵蚀沟宽深比大于边坡，边坡宽深比为
边坡上部最小，边坡中/下部最大，是边坡上部的 1．36～1．93 倍，侵蚀沟沿平台至坡脚总体上
呈“宽浅-窄深-宽浅”式发展;48 L·min
－1
流量下侵蚀主要集中在平台与边坡中部，侵蚀体积
占比分别为 29．9%、26．8%;60～84 L·min
－1
流量时，侵蚀集中在边坡上部，占总侵蚀体积的
36．1%～44．7%。结果可为陕北露天矿排土场平台-边坡系统沟蚀防治及侵蚀产沙模型的建立
和修正提供参考。

 In the open pit，runoff from the platform is large discharge and rapid afflux，which often
results in serious gully erosion of dump slope． The study of erosion process under catchment condi-
tions of the platform-slope system is still backward． In this study，field scouring experiments were
conducted to investigate runoff characteristics and sediment yield processes of the platform-slope sys-
tem under different flow discharges (48，60，72 and 84 L·min
－1
)． Our results showed that rill
erosion dominated the platform-slope system under the flow discharge of 48 L·min
－1
，and gully
was formed under 60－84 L·min
－1
． The flow velocity of the platform and the slope showed an
abrupting-fluctuating-stable trend with the duration of discharge． The flow velocity of the platform
was smaller than that of the slope，with the magnitude of reduction at 8．3%－67．1%． The highest
flow velocity appeared on the up-slop/down-slope，being 18．5%－44．6% higher than that of themiddle-slope． In general，the sediment yield rate of the platform and the slope varied with the dura-
tion of discharge，with the sediment yield rate of the slope being 17．4 times as that of the platform．
The ratio of gully width to depth showed substantial difference between the platform and slope． The
platform generally had the largest ratio than the slope． For the slope，the largest ratio appeared on
the middle-slop/down-slope，being 1．36－1．93 times as that of the up-slope． The morphology of rill
and gully along the platform to down-slope presented in the form of“wide and shallow-narrow and
deep-wide and shallow”． Ｒill erosion mainly concentrated in the platform and the middle slope
under the flow discharge of 48 L·min
－1
，contributed 29．9% and 26．8% of the total erosion
volume，respectively． When the flow discharge increased to 60－84 L·min
－1
，the largest average
across-section areas (1083．25－1737．86 cm 2 ) formed on the up-slope accounted for 36．1%－44．7%
of the total erosion volume． Our results provided evidence for modelling soil and water erosion of the
platform-slope system in opencast coal mine．