"Вестник МГСУ"

Subject: among the modern heat-insulating materials lightweight concrete on porous aggregates is widely used. Currently, porous aggregates are mainly represented by expanded clay gravel, which has some drawbacks in its physical and mechanical properties: high content of split grains and significant grain shape factor. The presence of split grains in expanded clay gravel leads to an increase in consumption of cement paste. Significant grain shape factor limits the use of expanded clay gravel in lightweight concrete of higher strength. Granulated foam glass is an alternative porous aggregate for lightweight concrete. It is characterized by high physical and mechanical properties and low values of thermal conductivity. Research objectives: in this article, the results of studies of physical and mechanical properties of expanded clay gravel and granulated foam glass are presented, the differences between these materials are revealed and the possibility of using granulated foam glass as a porous aggregate in lightweight concrete is studied. Materials and methods: properties of granulated foam glass and expanded clay gravel are determined according to the standards. Conclusions: according to the test results, it was found that granulated foam glass has higher values for a complex of physical and mechanical properties in comparison with expanded clay gravel, produced traditionally. However, the compressive strength test in the cylinder showed that the granulated foam glass has a significantly lower strength than the expanded clay gravel with the same value of their apparent density. Also during the tests, the possibility of using granulated foam glass to obtain a lightweight concrete corresponding to the grade class B5 and density class D1000 was established. In this case, there is a need to adjust the grain-size composition of the aggregate and component composition of concrete mixture.

A substantial amount of waste products of heat-and-power engineering has been accumulated
in Russian Federation up to the present time. The waste products include ash and other waste
materials. Their utilization is of particular significance in road building because this sector
demonstrates a high consumption rate of thermal engineering waste.
Physical and mechanical properties of the materials in question are different from the natural
properties of the soil, and they are determined by a variety of factors. Civil engineers tend not to
apply any waste products of heat-and-power engineering in soil building. The reason for that is that
the properties of these materials have not been examined thoroughly enough. The findings of the
examination of the properties of ash and waste products performed using the method of intensive
dynamic compacting satisfy the set of requirements developed by the road building authorities with
reference to the characteristics of the road embankment.

The article states that the use of spoil heaps (coal mining waste) in the production of structural ceramics is expedient. It shows the reduction of negative ecological effects during the life cycle when coal mining waste is used in the initial blend for the production of structural ceramics. It shows that the development of the recommendations for the use of coal mining waste in the production of structural ceramics is an urgent issue as far as the use of coal mining waste in the production of structural ceramics can lead both to the achievement of resource saving and positive ecological effect and to the undesirable decrease of the basic physical and mechanical properties of the final products when the structure of the mix is inappropriate. In order to develop these recommendations the authors have examined the microstructure, mineral composition and physical and mechanical properties of structural ceramics produced with the use of coal mining waste, which effect the consumer properties of the target material. As a result of the research the authors have made the conclusions about the nature and degree of impact of coal mining waste quantity on the physical and mechanical properties of construction ceramics. The comparison of the data received during the measurement of the basic physical and mechanical properties of construction ceramics with the results of the research of microstructure, elemental and mineral composition of the samples has shown their correlation.