Abstract

The main aim of the work is to study the effect of different fibres (steel, glass and basalt) on resistance of blast furnace slag-based alkali-activated mortar in acidic environment. The alkaliactivated slag mortars were exposed to 5% sulfuric and acetic acid solutions for 30 days. Mass change, compressive strength and microstructural changes were evaluated. In plain mortar, it was observed that 70% of the strength was retained in acetic acid environment whereas only 20% of residual strength remains in sulphuric acid environment. FTIR spectroscopy shows the degradation of the matrix, which implies the alkali-activated mortar was more vulnerable in sulphuric acid environment due to its aggressive nature compared to acetic acid. Decalcification and formation of calcium acetate also hinders the further progress of damage in acetic acid attack. Fibres helped in improving the performance of the mortar by holding the matrix together when the degradation occurred in acidic environment. Compared to plain mortar, incorporation of steel fibres exhibited a maximum strength retention of 19% in acetic acid and 7% in sulphuric acid, followed by glass and basalt fibres. SEM images clearly show the debonding of fibres and disintegration of matrix in acidic environment, which resulted in strength loss.

Abstract

Research aim - to produce conclusions that will result in the increase of the productivity and reduction of specific expense of fuel of tippers, while taking into account the tippers operational characteristics at transportation of metallurgical slags and products of their processing.. As a result of research the analysis of tippers of BelAZ-7540 exploitation was conducted on a metallurgical enterprise in the climactic conditions of southeast of Ukraine,. In addition, factors contributing to the efficiency of the tippers use have been distinguished and examined. It was found that the efficiency of the use of tippers, namely the studied change of expense of fuel is contingent on the work of tippers. Thus, in the process of research, there was the educed periodicity of oscillation of expense of fuel of tippers. The application of the research findings is that appropriate procedures are recommended in terms of the rational use of fuel, in particular, in the process of determination, planning, setting of norms of the necessary amount of fuel, which is one of the most essential and actual tasks for modern metallurgical enterprises today.

Abstract

"jats:p"A current worldwide economy problem includes both the responsible management of the planet's non-renewable resources and the waste management. The benefits of using recyclable materials and recycling technologies with asphalt mixtures consist mainly of reducing fuel consumption and greenhouse gas emissions. It is well known that oil (from which bitumen is obtained) is a non-renewable resource, hence the its price increase. Therefore, at present, the world is looking for solutions that will lead to a better use of natural resources and to an economic integration of sub-products from various industries. This paper intends to raise awareness of the possibilities for asphalt mixtures recycling and of the recyclable materials that can be used as additives with benefits of each. Document type: Article