The purpose of the research was to raise the level of environmental safety in the coal mining regions by using combustion metamorphic rocks of the spoil banks, which were reinforced with the modified wastes of the polymer production, namely carbonous binders, as a man-made raw material for the base courses of roads. The environmentally friendly technology for the construction of the base course of roads from layers of combustion metamorphic rock mixtures (CMRM) with different largest granule size of crushed stone was developed. The bulk density and compressive strength in a cylinder on a hydraulic press were used as the criteria for determining the rational granulometric composition. The practicability of reinforcing combustion metamorphic rocks with coal tar, which is a modified waste of the polystyrene production, i.e polystyrene dust, was shown. The technology of preparation of the tar and polystyrene binder (TPB) was developed. The optimal concentration of polystyrene dust in the organic binder of the coke production and the time of their combination (as the optimal areas of admissible values of variation factors X 1 , X 2 , X 3 ) were determined using the method of mathematical planning of the three-factor experiment (5 optimization parameters). The coefficients of the regression equations were calculated using the least squares method. Regression equations are a second-degree polynomial. The three-dimensional diagrams "parameters of system optimization -variance factors" were calculated and drawn. In accordance with the obtained regression equations, the response surface was designed in a three-dimensional space. The areas of admissible values of optimal variance factors correspond to the limit values of the response functions.

A floor heave is usually a serious failure phenomenon in mine roadways, especially in the conditions of a wet soft rock. There are bright prospects for using a method of reinforcing for controlling a floor heave in mine roadways under a dramatic heave. In the current research, a floor heave mechanism in the wet soft rock of mine roadways was investigated while the moisture content of the rocks was increasing. That was done by performing numerical simulations in a finite element analysis software system Ansys and by reinforcing the floor in the shape of inverted arch. It was found that a decrease in the modulus of elasticity of rocks caused by saturation leads to a nonlinear increase in a floor heave. This can be explained by the fact that rocks of the floor become plastic strains. A stable correlation was established between water content and a floor heave of a wet rock. It was found that when the floor is reinforced, the proportion of plastic strains in the soil is significantly reduced. The growth of the modulus of elasticity of rocks in the reinforced zone, caused by reinforcing of the floor in the form of inverted arch, leads to a nonlinear decrease of a floor heave. The effective range of floor reinforcing was established. A reliable relation was established between the ratio of the modulus of elasticity of rocks of the reinforced zone to the modulus of elasticity of the surrounding rock and heaving of reinforced rocks. The obtained results can be used to predict the magnitude of heaving of rocks at their saturation, as well as after they are reinforced.

Coal auger mining is a promising technology used for excavating thin coal seams. The efficiency of auger mining is largely related to the stability of mine roadways in the influence zone of the coal-face. Roof bolting systems are promising in such conditions. An adequate choice of roof bolting parameters is only possible if one understands the features of the stratification of the rocks and stages of deformation of the array in auger mining. Modern monitoring methods of the condition of rocks are based on the use of mechanical benchmarks, sounding of the mine array and the use of optical devices. There are few studies concerning roadways with auger mining. The innovations presented in this manuscript are a determination of the research results of the in-situ processes of rock deformation around a roadway in auger mining which will help to better understand the features of deformation processes in the technological method and design an adequate support system. Some field studies were undertaken in order to investigate the geo-mechanical processes that can be observed while auger mining a roadway with fully grouted bolts of 2.4 m in length. The research included monitoring rock stratification with the help of mechanical telltales, the convergence in the roadway using contour benchmarks, measurements of altitude and rock falls, and visual observations. The presented results show that roof-bolting can be used to support the roadways for auger mining.

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Стаття розглядає історію появи інженерно-технічної освіти в США. Здатність США підтримувати інновації перш за все потребує професіоналів, які мають високу кваліфікацію в галузі науки, техніки, інженерії та математики (STEM). Ці професіонали працюють в уряді, промисловості та науці. Інженери відіграють особливо важливу роль у розробці новітніх технологічних систем та процесів. Останні десятиліття політики, роботодавці, дослідники та освітяни приділяють пильну увагу системі інженерної освіти США та відповідності отриманих інженерних навичок сучасним потребам економіки країни. Поява та розповсюдження програм підготовки інженерно-технічних спеціалістів є результатом поєднання декількох ключових чинників технологічного розвитку в Сполучених Штатах. Такими чинниками стають бажання нації залишатися головним лідером у галузі технологій та інновацій; національні звіти про стан інженерної освіти; розвиток технічних університетів; розширення програм у галузі інженерно-технічної освіти; поступовий розвиток навчальних програм, що містять більший акцент на теоретичних знаннях. Інженерні навички та знання є вирішальними чинниками для інновацій і технологічного розвитку країни. Вони також сприяють довгостроковому економічному зростанню та допомагають вирішити основні суспільні проблеми. Саме тому важливо розуміти освітній та кар’єрний шлях інженерів, які втілюють отримані навички та знання, а також систему інституцій, стратегії розвитку, ринок, трудові та інші ресурси, що разом готують, розвивають і поповнюють запас інженерів країни.