The difficulties associated with performing direct compression strength tests on rocks lead to the development of indirect test methods for the rock strength assessment. Indirect test methods are simple, more economic...The difficulties associated with performing direct compression strength tests on rocks lead to the development of indirect test methods for the rock strength assessment. Indirect test methods are simple, more economical, less time-consuming, and easily adaptable to the field. The main aim of this study was to derive correlations between direct and indirect test methods for basalt and rhyolite rock types from Carlin trend deposits in Nevada. In the destructive methods, point load index, block punch index, and splitting tensile strength tests are performed. In the non-destructive methods, Schmidt hammer and ultrasonic pulse velocity tests are performed. Correlations between the direct and indirect compression strength tests are developed using linear and nonlinear regression analysis methods. The results show that the splitting tensile strength has the best correlation with the uniaxial compression strength.Furthermore, the Poisson's ratio has no correlation with any of the direct and indirect test results.展开更多
With the development of the Internet, the Internet language-a new social variant of language comes into being. Owing to its distinctive features, the Internet language draws extensive attention and evokes dispute. Sho...With the development of the Internet, the Internet language-a new social variant of language comes into being. Owing to its distinctive features, the Internet language draws extensive attention and evokes dispute. Should we make laws to restrict its development or be magnanimous and tolerant？ The present authors think that the dispute reflects the clash between the traditional culture and the ＂fast food＂ culture. The two cultures would co-exist harmoniously and co-develop healthily only if we cherish the law in the development of language and grasp the indirect correlation between them.展开更多
基金CDC/NIOSH for their partial funding of this work
文摘The difficulties associated with performing direct compression strength tests on rocks lead to the development of indirect test methods for the rock strength assessment. Indirect test methods are simple, more economical, less time-consuming, and easily adaptable to the field. The main aim of this study was to derive correlations between direct and indirect test methods for basalt and rhyolite rock types from Carlin trend deposits in Nevada. In the destructive methods, point load index, block punch index, and splitting tensile strength tests are performed. In the non-destructive methods, Schmidt hammer and ultrasonic pulse velocity tests are performed. Correlations between the direct and indirect compression strength tests are developed using linear and nonlinear regression analysis methods. The results show that the splitting tensile strength has the best correlation with the uniaxial compression strength.Furthermore, the Poisson's ratio has no correlation with any of the direct and indirect test results.
文摘With the development of the Internet, the Internet language-a new social variant of language comes into being. Owing to its distinctive features, the Internet language draws extensive attention and evokes dispute. Should we make laws to restrict its development or be magnanimous and tolerant？ The present authors think that the dispute reflects the clash between the traditional culture and the ＂fast food＂ culture. The two cultures would co-exist harmoniously and co-develop healthily only if we cherish the law in the development of language and grasp the indirect correlation between them.
