مقاله انگلیسی رایگان در مورد تاثير ريزساختار ترکيبات سنگی بر خواص مکانیک سنگ آن – الزویر ۲۰۱۸

Abundant high quality coal resources exist in the Ordos and Yulin coal fields, China, which have developed into an important modern coal production bases. However, the bedrock is relatively thin with low shear bond strength. This specific roof strata structure, as well as the high mining dynamic stress caused by the high strength mining. Severe dynamic disasters, such as large area roof falls and shield damaged were occurred by the high ground pressure. The specific physical and mechanical properties of the overlying strata are the internal factors causing the dynamic disasters. Therefore, the study of the physical properties of the overburden strata under this mining conditions is the fundamental research for the prevention of the dynamic disasters. In recent years, many scholars have researched in this area with great success. Many valuable achievements on strata movement and control, and the microstructures of the shallow buried have been produced [1–۱۲]. For micro-structure research, the relationship between micro-structure and rock mechanics properties has been analyzed [13–۱۵]. Lindqvist et al. studied the effects of mineral composition, grain size, porosity and micro-fissures on rock mechanics properties [16]. Johansson confirmed that mineral composition, micropore porosity, grain size and shape as well as lamination are the most important factors influencing rock mechanics properties, He also summarized the different characteristics of various mineral composition and structure porosity as well as their effects on rock mechanics properties [17]. Tug˘rul et al. recognized that the physical and mechanics properties of rock are functions of mineral composition and structure [18]. Prˇikryl concluded that the uniaxial compressive strength (UCS) of granite is closely related to its grain size [19]. Although many significant results have been obtained by numerous researchers in the past, there exist many problems in theoretical research and production process. Therefore the research on rock’s mineral composition, structure and rock mechanics, especially the relationships among them are needed. In order to study the effect of rock composition, micro structure and porosity on rock mechanics properties, five kinds of sandstones located at different depths were selected for this research. Their compositions were analyzed by X-ray diffraction instrument. The semi quantitative analysis of the components was carried out by using the Jade 6.0 analysis software. The microstructure characteristics were observed by using the scanning electron microscope of SM-6390LV.