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11.
Rapid, field‐based assessments of rock hardness are required in a broad range of geomorphological investigations where rock intact strength is important. Several different methods are now available for taking such measurements, in particular the Schmidt hammer, which has seen increasing use in geomorphology in recent decades. This is despite caution from within the engineering literature regarding choice of Schmidt hammer type, normalization of rebound (R‐) values, surface micro‐roughness, weathering degree and moisture content, and data reduction/analysis procedures. We present a pilot study of the use of an Acoustic Energy Meter (AEM), originally produced, tested and developed within the field of underground mining engineering as a rapid measure of rock surface hardness, and compare it with results from a mechanical N‐Type Schmidt hammer. We assess its capabilities across six lithological study sites in southeast Queensland, Australia, in the Greater Brisbane area. Each rock exposure has been recently exposed in the 20th/21st century. Using a ‘paired’ sampling approach, the AEM G‐value shows an inverse relationship with Schmidt hammer R‐value. While both devices show variability with lithology, the AEM G‐values show less scatter than the Schmidt hammer. We conclude that each device can contribute to useful rock hardness testing in geomorphological research, but the AEM requires further field testing in a range of environments, and in particular on older and naturally‐exposed rock surfaces. Future evaluations can extend this pilot study by focusing on sampling procedures, energy sources, and data reduction protocols, within the framework of a comparison study with other rock hardness testing apparatus. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
12.
邓丽娟  刘亮 《地下水》2009,31(2):17-19
依据新疆某水库周边耕地地下水水样化验数据,应用灰色关联分析与相关分析相结合的方法,分析了地下水主要成分与总硬度、总碱度、电导率及矿化度4个指标之间的关系.结果表明,总硬度变化主要受Ca2+影响,水中HCO3-含量与总碱度关系密切,电导率主要受Mg2+影响,Na+、K+和与Mg2+对矿化度有较大影响.通过相关分析,发现它们之间相关性极为显著.  相似文献   
13.
吕洪富  宋健 《探矿工程》2012,39(8):26-28,35
坚硬弱研磨性地层钻进效率低一直是敦化大蒲柴河金矿区钻探难题,通过投磨料、调整钻头技术参数等措施得到了一些改善,尤其是液动潜孔锤的成功应用,彻底解决了该矿区钻进效率低下难题;此外,对复杂坍塌、漏失、涌水不稳定地层采用重晶石粉加水泥灌注的技术措施,解决了孔壁严重垮塌问题。  相似文献   
14.
土壤表面划痕与颗粒碰撞磨蚀实验研究   总被引:1,自引:0,他引:1  
贾晓鹏  王海兵 《中国沙漠》2009,29(2):219-222
在沙漠地区,风蚀作用可以导致土壤表面破碎,土壤表面的性质不同,破碎的程度也不尽相同。划痕方法在测量土壤表面的比研磨能量上具有较好的效果,使用通用微型摩擦计(UMT)测量沙土、沙壤土、粉沙壤土、壤土,粉沙粘壤土和粉沙粘土6种不同土壤类型的土壤表面相对磨蚀能量和相对表面硬度,发现土壤表面相对硬度对土壤表面相对磨蚀能量有很大的影响。对沙土,沙壤土、粉沙壤土、壤土、粉沙粘壤土和粉沙粘土6种不同类型的土壤表面进行了颗粒碰撞磨蚀试验,结果表明,土壤表面的碰撞磨蚀速率与碰撞颗粒速度的平方成正比、土壤平均颗粒大小的2.6次方成正比,而与土壤表面相对磨蚀能量的1.5次方成反比,与土壤相对硬度的1.7次方成反比。  相似文献   
15.
由酸雨对包气带土样的淋滤试验和浸泡试验资料表明,在岩-水相互作用的初期,硬度主要来自土中易溶盐的溶解和H ̄+、Na ̄+对上颗粒表面Ca ̄(2+)、Mg ̄(2+)、Fe ̄(2+)等的交换;在后期,硬度主要来自土中碳酸盐、铝硅酸盐的风化水解。酸雨中的酸度与土壤溶液中的碱度的中和过程,即是水中硬度的形成过程;酸雨的pH值越低,在相同作用时间内形成的硬度值越高。是硬度组分自土中迁出的主要载体;岩水作用的时间越长,硬度值也越高。  相似文献   
16.
The Schmidt hammer is employed by geomorphologists as a convenient field instrument for measuring the hardness of rock surfaces. Field trials indicate that the readings obtained are a function of not only the hardness of the surfaces but also their texture. Smooth planar surfaces give much higher readings than rough or irregular surfaces. This makes interpretation of the results particularly difficult when the hammer is used to measure the hardness of natural rock surfaces that have been roughened by weathering.  相似文献   
17.
Physico-mechanical properties of rocks have great significance in all operational parts in mining activities, from exploration to final dispatch of material. Compressional wave velocity (p-wave velocity) and anisotropic behaviour of rocks are two such properties which help to understand the rock response under varying stress conditions. They also influence the breakage mechanism of rock. There are different methods to determine thep-wave velocity and anisotropyin situ and in the laboratory. These methods are cumbersome and time consuming. Fuzzy set theory, Fuzzy logic and Neural Networks techniques seem very well suited for typical geotechnical problems. In conjunction with statistics and conventional mathematical methods, hybrid methods can be developed that may prove to be a step forward in modeling geotechnical problems. Here, we have developed and compared two different models, Neuro-fuzzy systems (combination of fuzzy and artificial neural network systems) and Artificial neural network systems, for the prediction of compressional wave velocity.  相似文献   
18.
提出了一种能很好适应电镀金刚石钻头要求的新型胎体材料即镍钴锰三元合金镀层,给出了新镀层的电镀液配方,对比测量了镍钴锰镀层与目前广为采用的镍钴和镍锰镀层的硬度与韧性,结果指出,镍钴锰三元合金镀层具有比镍钴或镍锰镀层更高的综合机械性能和低得多的钴含量,更适合于制造电镀金刚石钻头,在适当条件下,镍钴锰胎体钻头可以分别更好地适应于镍钴和镍锰胎体钻头的应用领域。  相似文献   
19.
人类活动对河北平原地下水水质演化的影响   总被引:17,自引:1,他引:17       下载免费PDF全文
广大的平原地区和主要城市地区地下水水质的变化状况可以说明,人类活动引起了河北平原地下水化学组分的改变,其中硬度是一个普遍升高,且超标的化学组分,因此,认为硬度是反映人类活动对地下水影响的特征性化学指标,人类活动引起地下水的明显污染可以由铵来表征,通过对地下水硬度升高原因的分析,论述了人类活动影响地下水水质演化的基本机理。  相似文献   
20.
Summary Shore hardness has been used to estimate some mechanical and physical properties of rocks for many years. This study differs from previous studies in a way that it is directly oriented to rock cuttability. Two Shore hardness values (SH 1 andSH 2) and a coefficient of deformation value (K) have been measured for 30 different rock samples. In the first stage of the study, optimum specific energy values for 16 different rock samples obtained from full-scale cutting tests were correlated with the Shore hardness values of the same rock samples changingSH 1 values from 9 to 66 andSH 2 values from 25 to 83, with deformation coefficient values changing from 26 to 195. In the second stage, the performance of a roadheader used in the Kü?üksu (Istanbul) tunnel was recorded in detail and the instantaneous cutting rate of the machine was determined. Then, the relationship between Shore hardness values, deformation coefficient and the instantaneous cutting rate of the machine was determined for different formations encountered. It is concluded that there is a relationship between Shore hardness values, optimum specific energy and compressive strength, which may be used to estimate the rock cuttability and the instantaneous cutting rates of roadheaders within certain limits of reliability.  相似文献   
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