INTRODUCTION
The monograph includes 37 sections, each of which is devoted to a specific
problem of national economy’s sustainable development.
The first section “IMPROVEMENT OF THE AFFORDABLE HOUSING
PRECAST AND PRECAST-CAST-IN-PLACE BUILDING PRODUCTION
TECHNOLOGIES”. Precast and precast-cast-in-place technologies as promising areas
for solving the problem of affordable housing are considered. Improved design
solutions for the joints: hollow-core slabs with monolithic bearing girders and between
themselves in a precast-cast-in-place frame structural system, as well as with wall
panels in large-panel buildings; overcolumned slabs with columns in a structural
system with ungirder overlapping; wall panels on wire rope loops in large-panel
buildings are proposed.
Systematic theoretical and experimental studies of the keyed joints of concrete
and reinforced concrete elements, which made it possible to formulate
recommendations for their design and improve the existing design solutions of joints,
have been carried out at PoltNTU over the recent thirty years. The method for calculate
the strength of the joints is proposed. This method is based on the theory of concrete
plasticity, the variation method and the principle of virtual velocities. It considers the
stage of destruction and takes into account the full set of influence factors.
The second section “CHANGES OF FERTILITY RATES ON SOD-
PODZOLIC SOILS DURING THE CULTIVATION OF CEREAL GRASSES”. In the
average during the cultivation years of cereal grasses, the percentage of cereals to
motley grasses was in the range of 71 to 92%. Leaves proportion in cereals averaged
over the years of cultivation accounted from 35.4 to 42.5%. Productivity of all
investigated factors increased only by 0.13 – 0.20 t/ha or by 2-3% at HIP05 - 0.30 t/ha
on average over three years. Changes of physico-chemical parameters of soil under the
cereal grasses stemmed from the influence of the root system to penetrate into the
thickness of the soil profile. Established, that the content of mobile phosphorus and
exchangeable potassium increased in all variants of perennial cereal grasses, for
instance, during the cultivation of Festuca orientalis and Dactylis glomerata: Р
2
О
5
increased by 12% and К
2
О by 16.4% respectively. Cultivation of cereal grasses on sod-
podzolic soils caused an increasing of their fertility, in particular increasing of nitrogen,
phosphorus and potassium.
The
third
section
“PECULIARITIES OF DEVELOPMENT AND
PRODUCTIVITY
FORMATION
OF
MISCANTHUS
DEPENDING
ON
ELEMENTS OF GROWING TECHNOLOGY UNDER CONDITIONS OF
WESTERN FOREST-STEPPE”. In the work there were established the regularities of
dependence of conditions of growth, development and productivity formation of Giant
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