铅锌矿尾砂水稳层力学及耐久性研究OA
Research on Mechanical and Durability of Lead-Zinc Mine Tailings Cement Stabilized Base
为实现铅锌矿尾砂的资源化利用,规避土壤污染风险,拟将其作为水稳层浇筑材料.开展了不同水泥掺量和水胶比条件下铅锌矿尾砂水稳层的力学及耐久性试验,并进一步以重金属离子浸出试验探究水泥对铅锌矿尾砂中Pb2+、Zn2+等离子的固稳能力,最后利用微观测试手段表征了水稳层的物相组成及微观形貌.结果表明:随着水泥掺量的增加及水胶比的提升,将产生更多的C-S-H凝胶与AFt等水化胶凝产物,该类产物能够有效胶结铅锌矿尾砂颗粒并填补空隙,使试样微观结构更加密实,从而提升试样的宏观力学性能;当水泥掺量为6%、水胶比为0.5时制备的铅锌矿尾砂水稳层28 d抗压强度达到4.15 MPa,且经干湿、冻融循环后,其无侧限抗压强度保留率分别为73%~79%和88%~90%,均满足JTG E51-2009《公路工程无机结合料稳定材料试验规程》的要求;同时水泥可以有效固稳铅锌矿尾砂中的重金属离子,当水泥掺量为6%时,水稳层浸出液重金属质量浓度低于GB 5749-2022《生活饮用水卫生标准》中的控制值.相关研究成果可为铅锌矿尾砂的利用提供参考和借鉴.
In order to realize the resource utilization of lead-zinc mine tailings and avoid the risk of soil pollution,it is proposed to be the pouring material of concrete stabilized base.The mechanical and durability tests of the cement stabilized base of lead-zinc mine tailings were carried out under different cement content and water binder ratios.The stabilization ability of cement to Pb2+and Zn2+plasma in lead-zinc mine tailings was further explored by heavy metal ion leaching test.Finally,the phase composition and micro morphology of the cement stabilized base were characterized by microscopic test method.The results show that more hydration cementation products such as C-S-H gel and AFt will be produced with the increase of cement content and water binder ratio,which can effectively bond lead-zinc tailings particles and fill the gap,making the microstructure of the sample more denser,so as to improve the macro mechanical properties;When the cement content is 6%and the water binder ratio is 0.5,the 28 d com-pressive strength of the lead-zinc mine tailings cement stabilized base is 4.15 MPa,the unconfined compressive strength retention rates are 73%~79%and 88%~90%,respectively,which meet the requirements of JTG E51-2009 Test methods of materials stabilized with inorganic bindersfor highway engineering.At the same time,cement can effectively stabilize the heavy metal ions in the tailings of lead-zinc mine.When the cement content is 6%,the heavy metal concentration in the leaching solution of cement stabilized base is lower than the control value in GB 5749-2022 Standards for drinking water quality.The relevant research results can provide reference for the utiliza-tion of lead-zinc tailings.
杨桃;魏丽君;许睿霖;陈英豪;罗正东
聊城盛宏岩土工程有限公司,山东聊城 252000山东国亚市政工程有限公司,山东 聊城 252000湘潭大学土木工程学院,湖南湘潭 411105
化学工程
铅锌矿尾砂固废利用水稳层力学性能耐久性
lead-zinc mine tailingssolid waste utilizationcement stabilized basemechanical propertiesdurability
《市政技术》 2024 (008)
85-92 / 8
湖南省自然科学基金项目(2023JJ50008);湖南省研究生科研创新项目资助(QL20230154)
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