老木孔水库成库后乐山港港区河段泥沙冲淤演变研究

Sediment Scour and Silting Evolution Research at the Area of Le shan Port in Old Wood Hole Reservoir

乐山港位于老木孔水利枢纽库区河段,该段河床及水流条件复杂。为确保工程建设后航道畅通、港口正常使用,在定床模型基础上进行动床河工模型试验,以研究成库后泥沙冲淤演变及相应通航水流条件。试验结果表明:水库运行初期库区河床淤积较快,随着水库运用年限的增长,淤积速率逐渐放慢,至水库运用20a,库区河床冲淤尚未达到平衡状态;重点淤积部位在老江坝尾至坝址河段左右两岸边滩疏浚区,老江坝右汊及涌澌江口附近;水库运用20a,河床发生淤积,但库区航道尺度(航深、航宽、弯道半径)仍大于岷江三级航道标准,通航水流条件(流速、比降、流态)满足流量10 000 m3/s以下船舶的通航要求。

Leshan port is located in the old wood hole reservoir River.There river bed and flow conditions are complex.In order to ensure the smooth channel,normal use after the port construction,made a movable bed model test based on the fixed bed model test,to study the reservoir sediment scour and silting evolution and corresponding navigation flow condition.The test results show that,(1)Silting of riverbed is rapid in the early stage of reservoir operation,along with the reservoir operation for years,the depositing speed gradually slow down,to reservoir operation 20 years,reservoir bed has yet to reach an equilibrium state.(2)The main deposition sites are around the beach dredging area on both sides of the old river dam site to end,the right branch of old river dam and in the vicinity of Chung Adams.(3)Through bed sediment,but the reservoir area channel scale(navigation depth,boat is wide,the radius of the bend) is still larger than the channel three standard and the navigable flow conditions(flow rate,ratio,flow pattern of flow is 10 000 m3/s) satisfy the following requirements for ship navigation too,after the reservoir operates 20 years.