病险溢洪道混凝土溢流面加固技术探讨与实践  

Research and practice on reinforcement technology for concrete overflow surface of dangerous spillways

作　　者：李婵娟 LI Chanjuan(Beijing Miyun Reservoir Management Office,Beijing 101512,China)

机构地区：[1]北京市密云水库管理处,北京101512

出　　处：《北京水务》2024年第6期70-76,共7页Beijing Water

摘　　要：密云水库自高水位运行以来,由于水位落差较大,在闸后泄槽0+234~0+240 m附近出现2处混凝土气蚀情况,造成混凝土溢流面破坏,钢筋混凝土保护层被气蚀剥落,配置钢筋表面出现锈蚀,从而成为病险溢洪道。为解决此问题,选用新型混凝土进行修复,新建总长172 m泄槽,其中:第一段为沿轴线等宽57.8 m矩形泄槽;第二段为下游出口14 m长挑流坎;第三段为过闸室段后建76 m斜坡段(底板加厚0.6~1.3 m),坡度为2%;第四段是38 m反弧段(R=296 m,底板厚0.6 m);第五段是58 m斜坡段(底板厚0.6 m),坡度为15%;底板顶高程为126.55~140.00 m,总高差13.45 m。在对病险溢洪道混凝土溢流面进行加固修复后,泄槽工程各部位混凝土经受住了输水检验,期间最大流速与之前冲刷流速基本持平,同时在停水期间对修补的混凝土外观及状态进行复核,外观无异常,建筑物基本完好,使用功能正常,保障安全输水。Since the operation of Miyun Reservoir at high water levels,significant water level differences have caused two instances of concrete cavitation near 0+234~0+240 m in the discharge chute behind the sluice gate.This resulted in the erosion of the concrete overflow surface,the cavitation-induced spalling of the reinforced concrete protective layer,and the rusting on the surface of the reinforcing steel,which thus rendered the spillway dangerous.Through careful design and selection of new concrete for reparation,a 172 m long discharge channel has been newly constructed.The first section was a rectangular discharge channel with equal width of 57.8 m along the axis.The second section was a 14m long flip bucket at the downstream outlet.The third section was a 76 m slope section(with a thickened bottom plate of 0.6~1.3 m)built after the gate chamber section,with a slope of 2%.The fourth section was a 38 m reverse arc section(R=296 m,bottom plate thickness 0.6 m),and the fifth section was a 58 m slope section(bottom plate thickness 0.6 m)with a slope of 15%.The top elevation of the bottom plate was 126.55~140.00 m with a total height difference of 13.45 m.After reinforcing and repairing the concrete overflow surface of the spillway,the concrete in all parts of the discharge chute passed the water delivery test.The maximum flow velocity during this period was comparable to the previous scouring velocity.Additionally,the appearance and condition of the repaired concrete were rechecked during water stoppages,revealing no abnormalities.The structure remained intact,functioned normally,and ensured safe water conveyance.

关 键 词：病险溢洪道 混凝土溢流面 气蚀 加固技术 

分 类 号：TV873[水利工程—水利水电工程]