Action of laser radiation on rocks

Journal of Mining Science -     

Fractal properties of spectrum characteristics of electromagnetic radiation under failure of rocks and structural materials

The fractal characteristics of an electromagnetic radiation signal image in a frequency range are calculated. It is shown that the fractal dimension of time section of the signal can serve as a characteristic that the failure surface has formed. __________ Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 2, pp. 55–68, March–April, 2007.     

Identification of stresses in rocks on the basis of changes in density of infrared radiation flux

The efficiency of infrared radiometry as a source of information on changes in the stress state of rocks is substantiated experimentally. The experiments were conducted under conditions of pulse actions. An analysis of synchronized records of the mechanical state of the specimen and the corresponding variations in the intensity of heat flux from its surface shows the reliability of recording and evaluating “jumps” in stresses on the basis of radiometric data. The Gersevanov Scientific-Research Institute of Foundations and Underground Structures, Moscow. Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 6, pp. 48–53, November–December, 1999.     

关于岩石材料的流变力学模型

矿山岩体受力变形是在一定的时间和空间中发生。讨论其特性的流变力学模型主要有经验模型和组合模型两大类。近几年 ,出现了弹性 -粘塑性模型、滑移开裂模型、破裂间断波模型、突出流变机理学说及广义弹 -粘 -塑性模型等 ,有利于对岩石 (体 )材料力学性质的深入研究。     

基坑抗隆起稳定安全系数的算法对比分析

基坑隆起变形破坏是一种常见的基坑失稳形式。基坑隆起变形量监测存在一定困难,基坑坑底抗隆起稳定性分析主要是计算安全系数。目前基坑抗隆起稳定安全系数计算方法主要有极限平衡、极限分析和强度折减等方法。结合工程算例,采用上述3种算法进行基坑抗隆起稳定安全系数计算,对比分析了各种计算方法的适用性。结果表明,极限平衡传统算法忽略的工程因素较多,计算结果过于保守,通过修正可以提高适用性。极限分析与强度折减的计算结果较为准确,但极限分析的破坏模式和强度折减中基坑稳定临界状态容许隆起量仍需进一步研究。     

干湿循环作用下泥质白云岩能量机制试验研究

为揭示红页岩破坏的力学特性和能量演化规律,通过电液伺服机对红页岩进行三轴压缩试验,研究不同干湿循环作用下红页岩试样峰值强度特征、力学特性和能量演化规律。结果表明：干湿循环次数对红页岩的抗压强度有显著的影响,并呈负相关关系;干湿循环作用会使岩样破坏阶段的脆性减弱,延性增强,降低其物理力学特性;对比干湿循环作用前后试样的变形特征曲线图,红页岩原试样的变形量大于干湿循环作用后的试样变形量,约为后者的1.7倍;红页岩破坏后,原试样的耗散能增长速率为干湿循环作用后试样的2.4倍,因为干湿循环作用会软化红页岩岩石内部结构,使其破坏时体积应变变化缓慢,从而导致耗散能相比于原试样增长较慢。

     

Prospects for directional drilling in hard rocks

The study is focused on the existing methods of long directional borehole drilling in hard rocks in high-viscous oil and natural bitumen field development. The authors suggest improving the hard rock mass drilling process by combining percussion–rotary drilling and positioning systems.     

Transfer of infrared radiation energy from the final working member to the stope during electrothermal and electrothermomechanical breakage of rocks

Institute of Mining of Chemical Raw Materials, Lyubertsy. Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 4, pp. 47–53, July–August, 1988.