Calculation of stress field in immovable layer of loose material

The stresses and bulk densities in immovable layer of loose material are calculated using a method that is based on limiting stress state theory. The limiting and nonlimiting zones and influence of rigid bottom are taken into account.__________Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 5, pp. 69–76, September–October, 2004.     

不稳定岩层中煤仓反井钻机施工方法

王家寨煤矿-510m水平1#煤仓在掘进过程遇有4m多的岩石破碎带,本文介绍在破碎围岩中使用反井钻机施工煤仓及支护施工的方法.     

流动注射分光光度法测定有机相中铀的研究

使用流动注射分光光度法，以合并带流路模拟有机相铀标准系列溶液，从而求出未知有机相样品的铀含量。测定范围在10～200mg／L.时铀浓度与吸光度呈线性关系。载流溶液为异丙醇，混合显色剂组分为异丙醇、三乙醇胺、Br－PADAP和掩蔽剂。方法的相对标偏＜±5％。每次样品的测定速度为1min。本法具有3个特点：1）采用合并带模拟有机相铀的标准系列溶液，使测定方法的灵敏度高、准确性好;2）即使在少量混浊状态下也能进行定量测定;3）采用排带法，解决了蠕动泵管长期使用的问题。     

Estimation of the parameters of an imminent seismic event focus by the free surface strains

Dilatancy zones generated by an active internal source of isolated force in a heterogeneous rock mass are studied. Based on the solution of an inverse problem, the method is proposed for locating and determining the source focus parameters using the measurement data on strains of the daylight surface. __________ Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 3, pp. 25–35, May–June, 2007.     

地质统计学在预测煤层冲刷带中的应用研究

研究与计算验证结果表明，在采区与工作面设计布置阶段，运用地质统计学方法预测煤层冲刷带的发育与展布规律是可行的，能够保证估计偏差小，与实际情况吻合较好；采用合适尺度的正交网格实施已知区域冲刷带样本点数值的采集，是满足区域化变量准连续性和运用地质统计学方法的前提。     

东滩矿3煤顶板突水的影响因素

为了保证生产安全，分析了东滩矿3煤顶板发生的突水事故，并与大量地质钻孔资料（钻孔的岩性、冲洗液消耗量等）及水文地质资料进行对比，从而得出：构造、冒落带内岩性、含水层水文地质参数和发育高度、汇水条件以及矿山压力的影响等因素是东滩矿开采3煤顶板突水的主要影响因素．在现有水文地质资料缺乏的情况下，可以利用钻孔资料，如冲洗液消耗量在平面的分布等来估计、判断含水层的富水性或圈定3煤顶板含水层的富水区，最后提出了防治水的措施．     

贺西煤矿三采区运输巷扩刷变形分析与控制

基于扩刷施工后大断面巷道围岩控制难题,以贺西煤矿4#煤层三采区运输巷扩刷施工为研究背景,理论分析了扩刷后大断面巷道围岩控制难点,采用FLAC3D软件模拟了运输巷扩刷前后围岩铅直应力与塑性区的分布与演化特征。结果显示:扩刷后巷道围岩铅直应力集中区及塑性区分布范围明显增大,巷道浅部围岩存在3.5m厚连续均匀分布的"塑性环"。据此,提出锚杆索+注浆+U型钢棚等联合支护技术,锚杆支护后在巷道浅部围岩形成厚度为1.6m的预应力拱形承载结构。试验表明:巷道顶底板与两帮最大移近量分别为218mm和165mm,扩刷后巷道围岩变形得到了有效控制。     

Features of forming an explosive fracture zone in a hard rock mass

The effect of extended discontinuities in a hard rock mass on regularities of forming explosive fracture zones is considered. The comparison of the numerical and in situ experimental results permits to conclude that, in common with the known effect of seismic blast wave screenage, transformation of the wavefront configuration is of drastic importance. In a number of cases, that results in the generation of complex-structured fracture zones: new fractured zones can form beyond unbroken areas. It is demonstrated that the similar effects may cause redistribution of the blast energy and, as a consequence, the higher seismic efficiency produced by flat charge blasting as compared with concentrated charge blasting. __________ Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 3, pp. 65–76, May–June, 2007.     

Sources and growth dynamics of fecal indicator bacteria in a coastal wetland system and potential impacts to adjacent waters

Coastal wetlands are receiving increased attention as a putative source of fecal indicator bacteria (FIB) in Southern California coastal waters. We examined temporal trends of water and sediment-associated FIB after rain events along with spatial sediment characteristics at two sites within the Santa Ana River wetlands and made comparisons to FIB levels observed in adjacent surf zone waters. During the first two rain events, total coliforms (TC), Escherichia coli (EC) and enterococci (ENT) in wetland water and sediment samples peaked either on the same day or within several days of the rain event, while the third resulted in elevated wetlands sediment TC levels only. TC in adjacent coastal waters consistently peaked on the same day as the rain event and decreased quickly thereafter (within 1 day). The TC/EC ratios of surf zone samples consistently fell below 10, indicating an increased probability of human fecal contamination whereas wetland TC/EC ratios were higher, averaging approximately 60 and 14 at each site. These results suggest sediment-associated FIB populations may be distinct from those found in the water samples, or at least have internal dynamics independent of water-borne populations. Increases in sediment-associated FIB may be due to in situ population growth and/or increased survival due to changes in environmental parameters (salinity, moisture and nutrient input) resulting from the rain events. Spatial differences in between the two sites may be due to sediment differences such as organic content and finer grain size and/or discrete sources of FIB.     

Quantitative assessment of groundwater vulnerability using index system and transport simulation, Huangshuihe catchment, China

Groundwater vulnerability assessment has been an increasingly important environment management tool. The existing vulnerability assessment approaches are mostly index systems which have significant disadvantages. There need to be some quantitative studies on vulnerability indicators based on objective physical process study. In this study, we tried to do vulnerability assessment in Huangshuihe catchment in Shandong province of China using both contaminant transport simulations and index system approach. Transit time of 75% of hypothetical injected contaminant concentration was considered as the vulnerability indicator. First, we collected the field data of the Huangshuihe catchment and the catchment was divided into 34 sub areas that can each be treated as a transport sub model. Next, we constructed a Hydrus1D transport model of Huangshuihe catchment. Different sub areas had different input values. Thirdly, we used Monte-Carlo simulation to improve the collected data and did vulnerability assessment using the statistics of the contaminant transit time as a vulnerability indicator. Finally, to compare with the assessment result by transport simulation, we applied two index systems to Huangshuihe catchment. The first was DRASTIC system, and the other was a system we tentatively constructed examining the relationships between the transit time and the input parameters by simply changing the input values. The result of comparisons between the two index systems and transport simulation approach suggested partial validation to DRASTIC, and the construction of the new tentative index system was an attempt of building up index approaches based on physical process simulation.