滨海矿山充填假底中钢筋腐蚀行为与防护研究  

Study on the Corrosion Behavior and Protection of Reinforcing Steel Bar in Cemented Backfill Bottom of Coastal Mine

作　　者：齐宽 王昆[2] 林枝祥 QI Kuan;WANG Kun;LIN Zhixiang(CNACG Ecological Environment Technology Co.,Ltd.,Beijing 100067,China;College of Energy and Mining Engineering,Shandong University of Science and Technology,Qingdao 266590,China;263 Brigade of Jiangxi Nuclear Industry Geological Bureau,Nanchang 330000,China)

机构地区：[1]中煤地生态环境科技有限公司,北京100067 [2]山东科技大学能源与矿业工程学院,山东青岛266590 [3]江西省核工业地质局二六三大队,江西南昌330000

出　　处：《金属矿山》2021年第3期11-18,共8页Metal Mine

基　　金：中国煤炭地质总局科技发展专项基金项目(编号:ZMKJ-2018-2,ZMKJ-2017-01)。

摘　　要：滨海地区资源开发是当代矿业发展的趋势之一。充填采矿工艺中胶结充填假底稳定性是保障地下安全开采的关键,而滨海矿山深部盐卤环境极易造成其腐蚀失稳,成为滨海地区资源开发的一大阻碍。以国内某大型滨海金矿为工程背景,现场采集制样,通过实验室自制装置模拟还原充填假底内部腐蚀环境,采用电化学分析等方法研究充填假底内HPB235钢的腐蚀行为。水泥净浆试块强度试验及XRD衍射分析研究表明,盐卤离子有利于生成水化反应产物,并对胶结试块早期强度有利,充填假底失稳的主要原因为HPB235钢筋结构腐蚀。之后分别通过开路电位、极化曲线、电化学阻抗谱测试和失重法4种试验手段研究了各防护措施下的钢筋腐蚀行为,研究结果得到相互印证,均表明:未防护处理的试样发生严重腐蚀,腐蚀速率高达4.828 g/m^(2)/d;包裹环氧树脂涂层使得其自腐电流密度降低95.8%、腐蚀速率降低93.8%,防护效果较为显著,可尝试应用于滨海矿山充填假底施工中,以延长假底服役寿命,保障矿山安全生产;阻锈剂防护作用甚微,仅可作为辅助手段。The exploitation of resources in coastal area is one of the trends of contemporary mining development.Cemented backfill bottom(CBB)stability is the key factor of underground safety mining.However,the CBB can be corroded and lose strength easily under the brine environment in coastal mines,posing huge threatens to the coastal resource exploitation.Based on the engineering background of a large-scale coastal gold mine in China,this study collects samples on site,simulates the internal corrosion environment of the filling false bottom by using self-made laboratory equipment,and uses electrochemical analysis and other interdisciplinary methods are used to study the corrosion behavior of HPB235 steel in the CBB.The strength test and XRD analysis of cement paste test block show that salt halide ion is conducive to the formation of hydration reaction products,and is beneficial to the early strength of cemented test block.The main reason for the instability of CBB is the corrosion of HPB235 reinforcement structure.And the steel electrochemical corrosion behaviors under different protective measures are studied by open circuit current measurement,potentiodynamic polarization test,electrochemical impedance spectroscopy(EIS)and weight-loss method respectively.The result shows that significant corrosions have been found in the unprotected steel bars.The corrosion rate is up to 4.828 g/m^(2)/d.And the epoxy resin coating is proven to be an effective measure which can reduce the current density by 95.8%and the corrosion rate by 93.8%.However,the corrosion inhibitor can only be an auxiliary measure based on its limited effect.

关 键 词：充填开采 滨海矿山 胶结充填假底 钢腐蚀 电化学测试 

分 类 号：TD853[矿业工程—金属矿开采]