关于中硬以下岩石合金钎头的刃角问题

在机掘坑探打眼工作中,过去一直认为无论打什么岩石,所用的合金钎头刃角都不应小于110°±2,否则合金就崩刃、掉角,笔者在中硬以下岩石(6-8级)中将合金钎刃自110°减小至100°~90°进行了打眼试验。通过三个月的长期观察和一个时期的实际测定结果证明:不仅钻速提高20%左右,而且从未发生崩刃、掉角等不正常损坏现象。测定资料见下表:     

典型窝崩三维数值模拟

窝崩是冲积河流常见的一种崩岸类型,具有发展速度快、破坏力强等特点,且不易成功模拟。以长江下游扬中河段指南村窝崩为例,基于窝崩机理及其力学模式,采用考虑回流区紊动影响的挟沙力公式模拟窝塘内泥沙输移,初步建立了窝崩三维数值模拟方法。研究结果表明:窝崩发生初期窝塘内局部水流具有底层流速大于上层流速的特征,这为窝塘底部及坡脚淘刷提供了动力条件;窝塘内回流区水流挟沙力的计算对窝崩形态模拟结果存在显著影响,考虑回流区紊动影响的泥沙输移特性后,模拟结果与实测结果基本吻合,可较好地模拟窝崩的快速发展过程。研究成果可为窝崩机理的深入认识和窝崩治理提供科技支撑。     

Environmental investigation for causality and remediation of cadmium contaminated soils in Tak Province, Thailand

Highly elevated cadmium concentrations in paddy soil in the Mae Sod District, Tak Province, Thailand, was detected and widely reported in 2003. This emergence provoked public interest and demands for responsibility and remedial actions. As zinc mines and concentrator were located in the upstream area, mining activities were proclaimed a contamination source. Department of Primary Industries and Mines （DPIM）, a governmental organization responsible for mining and mineral processing, was thus challenged to verify the reliability of post monitoring data displaying consistently low heavy metal concentrations in compliance with the standard limits for over 15 years. Detailed survey and deep-going research on the causes, boundary and severity of cadmium contamination as well as the environmental impact alleviation were consequently conducted. Environmental samples were accumulated systematically for 2 years throughout the areas of upstream and downstream mining sites. A total of 259 soil samples from 53 spots at the depths of 0-20, 20-40, 40-60 and 60-200 cm were drilled with hand auger. Samples of water, stream sediment and mine tailing were also collected. Chemical analysis for cadmium （Cd）, zinc （Zn） and lead （Pb） concentrations with AAS and ICP were undertaken. The contaminated area was finally defined to spread over approximately 18 square kilometer mainly of mountainous mineralizing land and colluvium.     

南极中山站地区冰崩概况

本文是根据１９９４年在南极中山站首次使用数字触发地震仪测量的冰崩，研究南极中山站地区冰崩规律及其与自然环境（温度，风速等）的关系，这对于考察船在南极的安全航行以及科考人员的人身安全都有极为重要的意义，并且对于南极冰川，冰山，冰盖等方面的科学研究有参考价值，结果表明１～９月份冰崩次数曲线呈口朝上抛物型变化，１０～１２月冰崩次数急剧增加，冰崩曲线与月最低气温、最高气温、月平均气温三者的拟合曲线吻合得很     

Formation Mechanism and Stability Assessment of the Colluvial Deposit Slope in Zuoyituo

The basic features of the colluvial deposit slope in Zuoyituo such as geological conditions, dimensions, slip surfaces and groundwater conditions are described concisely in this paper. The formation mechanism of the slope is discussed. It is considered that the formation of the colluvial deposit slope in Zuoyituo has undergone accumulation, slip, load, deformation and failure. The effects of rainfall on slope stability are categorized systematically based on existing methodology, and ways to determine the effects quantitatively are presented. The remained slip force method is improved by the addition of quantitative relations to the existing formulae and programs. The parameters of the colluvial deposit slope are determined through experimentation and the method of back-analysis. The safety factors of the slope are calculated with the improved remained slip force method and the Sarma method. The results show that rainfall and water level in the Yangtze River have a significant effect on the stability of the colluvial deposit slope in Zuoyituo. The hazards caused by the instability of the slope are assessed, and prevention methods are put forward.     

中国崩滑堵江事件及其环境效应研究

崩滑堵江事件在世界范围内,尤其在山区广泛存在.中国也是崩滑堵江现象较为多发的国家之一.笔者在长达十余年的研究基础上,收集和调查了170余起典型崩滑堵江事件,并以岷江和金沙江流域为重点进行了现场调查.在此基础上,以系统论为指导思想,研究了崩滑堵江事件的全过程,并对其发育分布规律、类型及特点、堵江危险度评价、溃坝洪水灾害、环境效应以及综合治理利用等进行了全面深入研究.     

陕北洛川塬黄土崩滑及谷坡扩展模式

陕北洛川黄土塬是水土流失严重的地区。通过野外调查发现黄土崩滑作用是造成该区水土流失的主要之一，发育于黄土塬-沟谷过渡地带。该区黄土崩滑首次被划分为单面崩滑及栅格崩滑两种基本类型。黄土单面崩滑主要分布于冲沟、切沟地貌环境，而栅格崩滑主要分布于级别较高的沟道之中，活跃于区域Ⅲ、Ⅳ级沟道，显示出黄土崩滑与区域水文网之间的对应关系。根据地貌景观和沟谷几何特征第一次提出洛川黄土塬河道谷坡以陡倾加宽和鱼鳞状后退扩展为模式。黄土崩滑是蚕塬的重要方式，在水土保持过程中，就加强不同类型崩滑的针对性研究、预报和防护治理，促进水保效益的提高。     

山体崩滑破坏的视滑力问题──以链子崖危岩体为例

本文提出了山体崩滑破坏的视滑力概念,给出其分析方法,并结合长江三峡链子崖危岩体进行了应用研究。它对于认识斜坡变形破坏的机理,改进稳定性评价,提高防治工程方案的针对性与工程布置的准确性有重要意义。     

雨强对安溪县尧山村滑坡地下水渗流系统及稳定性的影响研究

本文以安溪县尧山村滑坡为研究对象,通过现场走访调查、工程勘查和专业监测等手段,查明了研究区的地形地貌、地层岩性、地下水管网渗流系统的发育特征、坡体变形破坏模式、分布特征以及变形破坏范围等实际情况。然后基于FEFLOW软件构建出研究区的三维地下水渗流模型,探寻在不同雨强条件下研究区的地下水渗流场变化规律,再利用FLAC强度折减法计算滑坡体滑动面深度及其稳定系数。结果表明,崩坡积碎石土滑坡的地下水管网状渗流系统发育,坡体不仅只表现为拉裂型变形破坏特征,而且地面沉降和地面塌陷等特征也十分明显,在雨强165.5 mm·m-1和317.7 mm·m-1条件下,地下水位较天然工况分别上升0.5~1.5 m和0.5~2.5 m,滑动面深度9~12 m,稳定系数分别是1.04和0.97,通过分析比对,模拟结果的误差值都在容许范围之内,并与现场调查和实际监测的数值均较为吻合。因此,采用“盲沟盲管+截排水沟”为主要工程治理措施。