针对尾矿库埋入式监测仪器或传感器在不同的地下环境中腐蚀严重、经济损失大等问题,采用挂片浸泡、扫描电镜(SEM)、失重法和电化学测试相结合的方法研究了传感器外壳材料(以316L不锈钢为研究对象)在酸性环境和盐卤环境中的腐蚀规律.结果 表明,在pH1.5的酸性腐蚀环境中,不锈钢试样短期内钝化膜处于逐渐形成状态,耐蚀性越来越好;经过长期1a浸泡腐蚀后,耐蚀性略微有所降低;在pH3的硫酸与卤水混合液和pH7.5盐卤水的腐蚀环境中,不锈钢试样短期内耐蚀性越来越好;经过长期浸泡腐蚀后,由于盐卤水中侵蚀性Cl-的存在加速了钝化膜的溶解和破坏,耐蚀性下降幅度明显增大.

资源民族主义作为一种影响国际矿业投资的重要因素,在社会政治和经济形势剧烈波动的大背景下,对海外矿业投资风险的影响越来越明显,尤其在发展中国家,资源民族主义现象更加活跃.针对中国海外矿业投资项目面临的国有化风险,在分析资源民族主义成因及表现形式的基础上,通过梳理Grasberg、Ok Tedi、Porgera 3座矿山资源国有化的案例进程,分析了3座矿山不同的资源国有化背景及起因.通过对国有化过程及其影响范围的分析,展现了资源民族主义现象的复杂性,并从资本的角度揭示了资源民族主义的实质.提出了增强风险认知、利用商业保险、慎重投资决策、注重法律手段等应对策略,对中国海外矿业投资项目风险防范具有重要的指导意义.

为探究尾砂入料浓度、絮凝剂分子量、絮凝剂单耗、絮凝剂溶液浓度对全尾砂絮凝沉降与浓密的影响,以最大沉降平均速度、最终沉降浓密时间、极限底流浓度作为考察指标,对某金矿全尾砂浆展开了絮凝沉降与浓密正交试验.利用SPSS 23数理统计软件对试验结果进行了方差分析.结果 表明:影响最大沉降平均速度、最终沉降浓密时间、极限底流浓度3个指标的显著性顺序依次为尾砂入料浓度、絮凝剂分子量、絮凝剂单耗、絮凝剂溶液浓度.推荐该金矿全尾砂絮凝沉降与浓密的最佳条件为:全尾砂砂浆入料浓度20％,絮凝剂分子量1500万,絮凝剂单耗40 g/t,絮凝剂溶液浓度0.3％.

为弥补传统基于GPS/GNSS的单点监测方式无法反映尾矿坝整体变形的局限性,提出1种结合坝坡现有位移监测系统的无人机尾矿坝边坡表面变形监测方法.利用单镜头轻小型多旋翼无人机和计算机视觉技术对尾矿坝的空间三维地理信息进行数据采集与重建;基于设置在坝坡表面的位移人工监测点(水泥桩)对多期尾矿坝点云数据进行配准;通过对不同时期尾矿坝点云数据距离的计算实现对其边坡表面变形的整体监测.结果表明:经过雨季冲刷,山东某尾矿坝局部边坡出现冲沟、滑塌、表层滑移等现象;提出的方法能够精细地体现出尾矿坝边坡的整体变形与细节变化,可为尾矿坝边坡整体变形监测方法的拓展提供参考.

针对大型尾矿库溃坝灾害问题,目前大多数研究没有考虑真实地形的影响,往往对模型进行了简化.将近年发展起来的无人机摄影测量技术应用到尾矿库溃坝模拟研究领域,使用专业航测无人机对山东某尾矿库进行摄影测量,获取库区及下游区域的影像及POS数据,然后通过摄影测量三维重建软件,生成了高精度三维模型,重建影像分辨率达到2.74 cm/pixel,三维模型的精度达到了厘米级.基于无人机摄影测量三维重建的高分辨率地形,应用三维计算流体力学软件对尾矿库进行溃坝模拟,得出了尾矿库溃坝后渍决水流和尾砂的淹没范围及演进规律;通过在下游不同位置布设监测点,得出不同监测点处水流速度、淹没深度及尾砂的淤积厚度随时间的变化规律,预测了渍坝后果及危害程度.

Unmanned aerial vehicle (UAV) remote sensing is a state-of-the-art technology that integrates UAV, remote sensing sensor, GPS differential positioning, communication, and other technologies to achieve rapid collection, processing, and analysis of geographic environmental information. UAV remote sensing is considered an important supplement of spaceborne remote sensing and is recently being widely used in the topographical surveying and mapping, precision agriculture, heritage inspection, and emergency rescue, etc. For the traditional mining industry, high-quality and real-time UAV remote sensing data can be obtained at reasonable costs and benefit the mining operations, particularly for numerous small- and medium-scale mining sites where equipments and professional expertise are expensive. However, application scenarios of UAV remote sensing in the mining industry are rarely reported and lack systematic review. Therefore, the definition, platform composition, current status, and general workflow of UAV remote sensing technology were summarized in this study. Then, through significant domestic and foreign literature surveys, the application scenarios and practical case studies of UAV remote sensing in the mining industry were systematically presented. Finally, the development trend was analyzed on the basis of the shortcomings of current technology. Results show that (1) UAV remote sensing technology has the advantages of low costs, strong maneuverability, flexible data sampling settings, timeliness, repeatability, and high resolution. (2) The current applications of UAV remote sensing in the mining industry mainly include the operations management of open-pit mines, safety monitoring of tailing ponds, emergency rescue, environmental monitoring of mining areas, and prevention and control of slope disasters. (3) The development trend of UAV remote sensing technology application will include the standardization of UAV supervision, simplification of UAV control mode, augmentation of UAV endurance time, improvement of the quality of results, and further expansion of application scenarios. UAV remote sensing technology has broad application prospects in the mining industry and is bound to become an indispensable part of smart mines.

为探究在不同酸碱性流体环境作用下孔隙比、浸泡时间对尾矿砂渗透性的影响规律,选取7组不同孔隙比试样,设计变水头渗透室内试验;通过控制变量法,研究8种浸泡时间下尾矿砂渗透性变化规律,并利用扫描电镜和X射线能谱仪分析不同化学条件下孔隙比对尾矿砂渗透性影响机理.结果表明:在化学条件下尾矿砂的孔隙比与渗透系数存在"似指数"变化关系.当控制试样孔隙比为0.65时,在强酸溶液中(pH=3),尾砂的渗透系数随浸泡时间延长而增加,表现为二次抛物线关系,浸泡1600 s较浸泡200 s增加了56.92％;在强碱环境下(pH=11),尾砂的渗透系数随浸泡时间呈Logistic函数下降,浸泡1600 s较浸泡200 s下降了73.66％.基于太沙基、柯森、刘杰等渗透理论拟合得到酸性、碱性、中性三种条件下的修正关系模型.根据试验结果分析和扫描电镜观察发现,酸性条件下小颗粒尾砂被侵蚀,大颗粒尾砂棱角凸显,结合水膜变薄,孔隙增大,渗透系数变大;碱性条件下,尾砂颗粒表面与尾砂颗粒间有沉淀胶体覆盖或填充,结合水膜变厚,孔隙减小,渗透系数随之减小.

为改善充填砂仓中砂浆的流变特性,创新性地将超声场引入,利用声场辐射方式传播的特性,将超声场非接触性地作用于全尾砂砂浆介质中,研究充填砂仓中全尾砂砂浆在超声场作用下的流变特性.采用Brookfield R/S-SST软固体流变测试仪,测得不同浓度全尾砂砂浆的流变参数,并结合超声波作用机理分析其作用效果和影响原因.试验结果表明:分别对70％、72％、74％、76％和78％五种浓度全尾砂砂浆施加20 kHz和40 kHz两种频率下36 W、62 W、85 W、100 W的超声,黏度降幅可达6.421％ ～23.504％,屈服应力降幅达7.773％ ～33.125％.塑性黏度与功率存在显著的线性关系,屈服应力与功率存在明显的线性、二次、Boltzmann、Logistic分布关系.在其他试验条件相同的情况下,总体上40 kHz比20 kHz的超声作用效果相对明显,高功率优于低功率;超声波不仅能使砂浆颗粒产生机械振动,而且能产生明显的空化效应和热效应,在降低全尾砂砂浆的塑性黏度和屈服应力、改善砂仓中尾砂浆流动性和砂仓放砂等方面具有显著的优越性.

As industrial waste, the comprehensive utilization of fly ash involves many fields, among which it is widely used in cement mortar and concrete. As brine water is used in the preparation of filling slurry of Sanshandao Gold Mine, the chloride ions in the slurry have a great negative effect on the strength of the backfill. Therefore, the effects of fly ash and lime on the transport performance and the mechanical properties of cement mortar test blocks were studied by experiment. Based on fly ash XRD analysis, cement mortar block scanning electron microscope test (SEM) and fly ash with various amount and different way of adding test, the mechanism of improving the strength of the cement mortar test block produced by the fly ash and the best mixing amount of the fly ash were determined under the condition of brine water through experiment and theoretical research. Application of fly ash in undersea metal mine is a major breakthrough in the application of filling materials of metal mine undersea metal filling, having great effect on reducing the adverse effects on the strength of the filling body of bittern ions and improving the strength of the filling body.

为提高全尾砂料浆浓密沉降效果,降低脱水浓缩成本,将声波引入全尾砂浓密沉降试验中,探究声波对全尾砂料浆浓密沉降影响.利用清水与全尾砂料浆对比声压分布规律试验预选出合适的声波频率和功率,进而运用控制变量法,对声波作用参数进行优选,分析不同条件下全尾砂浓密沉降速度和底流浓度变化规律,探索声波在全尾砂料浆浓密沉降中的作用机理.结果表明:相同点的声压在全尾砂料浆中为70％的清水中声压值;当声波频率为100 Hz,功率为8 W,施加时刻为15 min时为最优作用条件,与自由沉降和絮凝沉降(单耗20 g/t、0.2％絮凝剂溶液浓度)相比,沉降速度分别提高了56.759％和0.801％,底流浓度分别提高了2.54％和6.302％;在合适的声场条件下,声波可明显提高全尾砂料浆沉降速度和底流浓度.

The mechanical performance of cemented paste backfill (CPB) placed in deep stopes often differs from laboratory-predicted performance, and the strength of CPB is generally determined to the uniaxial compressive strength (UCS) after the predetermined curing ages in laboratory. However, in situ backfilled stopes, the CPB is enclosed by the orebody and surrounding rocks usually, and the mechanical performance of CPB should not only be determined by the UCS. To investigate the mechanical performance of CPB in deep stopes during long-term service, the physical and mechanical conditions of CPB in situ backfilled stopes were simulated by the confined high-stress consolidation (CHSC), and the microstructure of CPB made by scanning electron microscopy was analyzed, and the strength regeneration mechanism of CPB was investigated from the microscopic point of view. The results showed that the strength of CPB in deep stopes could be excited to various degrees during long-term service, and the degree of excitation was closely related to the curing ages of CPB. The degree of excitation of the CPB strength was determined by the maximum confined consolidation stress, and the consolidated CPB was more beneficial to its supporting role in engineering. The macroscopic strength of CPB after CHSC can be increased by the increase of bond strength at the interfacial transition zone and the improvement of overall compactness of CPB. The re-filling and re-cementation of micro-cracks result in the strengthening of CPB during the re-curing ages. Compression consolidation (primary consolidation) and chemical consolidation (sub-consolidation) of CPB in the backfilled stopes occur simultaneously, and this is obviously different from the process of the compression consolidation of soil.

The effect of acid and alkali ions in the tailing pond on the sedimentation, microstructure, material composition and particle size gradation of tailings particles were investigated by the laboratory tests such as scanning electron microscopy (SEM), energy dispersive spectrometer(EDS), X-ray diffraction(XRD)and LMS-30 laser particle size analysis.A mathematical relationship model of void ratio and permeability coefficient under the influence of acid and alkali was established,and the model was used to characterize the coupling mechanism of stress field and seepage field in the tailing pond,so as to realize the purpose of substituting into the finite element calculation software.The results showed that the existence of chemical factors affected multiple characteristics of tailings particles.In the acidic environment, the tailings particles were corroded and partial metal elements were lost.While in the alkaline environment,the cementing material was produced between the tailings particles, and the flocculent and cluster stemming mainly containing the ferric hydroxide appeared in the pore,which changed the seepage velocity.The height of phreatic line in the tailing pond decreased in the alkaline,neutral and acidic environment in turn,while the seepage velocity increased in turn.

基于实测数据,对同一水平平台爆破震动监测的数据进行线性回归分析,得到爆破震动在水平地形上传播的萨道夫斯基衰减公式.在相似地质条件下,将不同高程的实测数据与该点使用水平地形上衰减公式计算的数据进行对比,验证凸形地貌对爆破震动传播产生的放大效应,并将获得的结论通过经验公式进行了验证;试验分析发现,相近高程、相同最大段装药量条件下,随着爆心距的增加,爆破震动的放大系数逐渐减小,超过一定距离后高程放大效应消失;在相近高程、相同爆心距条件下,随着最大段装药量的增加,高程放大系数反而逐渐减小;爆破震动垂向速度的高程放大系数随爆心距的增加逐渐减小,径向速度的高程放大系数随爆心距的增加表现较为稳定.

为了改善高浓度充填料浆的流变特性,降低充填系统中堵管现象发生的概率,将超声波非接触性地作用于充填料浆.采用高精度Brookfield R/S-SST软固体测试仪,通过试验检测得到超声波作用下不同浓度、不同灰砂比全尾砂充填料浆的流变参数.结果表明:超声波可以显著改善充填料浆的流变特性,降低充填料浆的塑性黏度和屈服应力,超声对料浆黏度值的降低效果可达4.32％～39.33％,对料浆屈服应力的减小效果可达9.66％～34.27％.同时,借助支持向量机建立充填料浆流变参数预测模型.所得预测模型校验结果显示,该模型精度较高,具有较强的泛化能力,实现了功率超声条件下充填料浆流变参数的预测.

为了深入研究煤矿事故频发原因和规律,基于国家安监总局煤矿事故查询系统得到的数据,从事故发生级别、类型、地点3个维度对我国近十年的煤矿事故进行了研究.并利用SPSS21软件构建了重大、特重大事故与瓦斯、火灾的关系模型.结果表明:较大和重大事故得到了有效地遏制,但特大事故时有发生,并容易反弹;在事故类型中顶板事故最为频发,瓦斯是造成一次伤亡最大的煤矿事故.贵州煤矿安全形势最为严峻,山西、黑龙江、内蒙古、重庆4省占全国煤矿特重大事故起数和死亡人数分别53.3％和63.8％.重大、特重大事故死亡人数与瓦斯事故死亡人数关系为二次关系,与火灾事故死亡人数为增长关系.

Sanshandao Xinli Gold Mine in Shandong Province is the first Chinese subsea gold mine. The mine uses cement backfill in the open stopes. The existence of a high concentration of Cl− in the water use to create the cement backfill affects its strength. An analysis by scanning electron microscopy and x-ray diffraction investigated the effect of salt brine on mechanical properties of cement backfill and micro-corrosion mechanism, the suitable mineral admixture of fly ash was selected after conducting theoretical analysis to decrease the effects of brine. A relationship between the elastic modulus and the uniaxial compressive strength of the cemented backfill was determined. The density, cohesion and internal friction angle of the cemented backfill were obtained. Based on x-ray diffraction analysis of fly ash, scanning electron microscope test and testing the addition of fly ash in varying amounts and ways of introduction, the mechanism for improving the uniaxial compressive strength of the cement backfill produced with the fly ash and the best mixing quantity of the fly ash was determined in briny conditions through experiments and theoretical research. Rheological properties of the filling slurry with fly ash were also investigated.

为提高全尾砂料浆浓密沉降的质量浓度,将超声波引入全尾砂料浆浓密沉降试验中.利用MATLAB模拟超声波在全尾砂料浆中的指向性,进而选取出超声波频率范围.采用Design-Expert软件设计,并分析不同条件下超声波对全尾砂料浆最终质量浓度的影响,以及各因素之间的耦合关系,进而优化超声波作用条件.结果表明:当超声波频率为20～40 kHz时,在砂仓中传播指向性较好;超声波外场作用能显著提高全尾砂料浆的最终质量浓度,当全尾砂自然沉降19.77 min后,施加频率20.02 kHz、功率50 W的超声波为最优作用条件,全尾砂料浆最终质量浓度可达77.51％,比自然沉降的最终质量浓度提高4.60％;在合适的超声场条件下,超声波在提高全尾砂料浆的最终质量浓度具有明显优越性.

为提高某缓倾斜薄至中厚多层难采复杂石墨矿体的采场生产能力和采矿效率,降低采矿成本,采用条带式开采嗣后胶结充填法.该方法考虑开采安全、成本、损失贫化率、回采率等技术经济指标因素,根据矿体多层产出、厚度不一、矿岩不稳固等开采条件,分别提出单层浅孔条带式充填采矿法、多层合采条带式充填采矿法和中深孔条带充填采矿法.生产实践表明:该方法不仅能保障安全,还大大降低了施工难度,且各项技术经济指标得到了明显改善;其中采场生产能力提高了68.25％,采矿工班效率提高了48.84％,采矿成本降低了33.98％,为企业带来了较大的经济效益和社会效益.

Tailings dam failure accidents with limited emergency response time and substantial potential threats often lead to heavy casualties and severe financial losses. In recent years, the decreasing trend of tailings dam failure accidents shows the development of modern technology and safety management. However, the frequency of major tailings dam failure accidents has increased, rather than decreased. The 2015 Samarco Accident in Brazil and the 2014 Mount Polley Accident in Canada, along with their disastrous consequences, once again sounded the alarm to improve the safety of tailings ponds. China is now facing a complicated safety situation because there are 8869 tailings ponds throughout the country, including 1425 overhead tailings ponds that represent the tailings ponds located within 1 km upstream of residential areas, workshops, schools, or other important facilities. Based on a large number of relevant research studies, focusing on three main aspects of accident prevention and management that include safety monitoring, early-warning and emergency preparation, safety management codes and standards, the status and frontier progress are reviewed in this paper. Furthermore, the relevant problems in China are discussed, and several improvement recommendations are presented that can provide a reference for theoretical research and technological innovation for preventing tailings pond accidents. The results are as follows:(1) The safety monitoring standards in China are relatively strict. However, the monitoring instruments lack stability, reliability, and practicability. Thus, specific devices and new technologies need to be developed. (2) The current early-warning method lacks diversity and reliability, and using information technology in interdisciplinary applications is becoming the developing trend. (3) The emergency management and decision-making should be based on sufficient scientific proof. However, the relevant research is limited by test methods and simulating algorithms. (4) Lastly, China has established a complete system of safety management codes and standards, but with the current problems of safety level classification, life-cycle management, change management process, and accident investigation, greater progress is needed.

本文全面分析了新时期大学生特点以及实习面临的问题,结合专业培养目标,提出了工科专业生产实习由传统体力参与到智力参与的实习模式,对大学生在生产实习中参与的环节及参与程度进行了规划设计,制定了实习效果评价体系及实习效果持续改进措施.