Ключові слова: максимальні витрати, швидкість
добігання, середньозважений діаметр наносів, руслоформуючі витрати, мезоформи, руслові
деформації.
Korbutyak V.M. Improvement of calculation methods of maximum runoff determination
by parameters of fluviomorphological process
The dissertation is dedicated to theoretical
generalization and new methods of solving of scientific task of determination
of calculation maximum cloud-burst water discharge values under missing or
insufficiency of hydrometric observational data for river of Ukrainian
Carpathians. Designing, construction and maintenance of flood-control and
coast-protecting structures, heavy using of the Ukrainian Carpathians water
resources and its preservation require corresponding scientific ground.
Experience of structures operation on Carpathians rivers point to low efficiency
and short life span of many types of structures, that is explained by failure
to take account of features of riverbed deformations development at
flood-control and coast-protecting works (incorrect composition without
forecasting of deformations development), riverbed deformations caused by
quarrying of river sediments from flood-lands and riverbeds.
At the present day evolution of
fluviomorphological process theory gives new point of view on phenomena, that
takes place in water flow. It opens up possibilities for determining hydrologic
parameters by studying of main energetic, morphological and physiographical
factors, that effect on forming of different riverbed types. Developing of
regional methods of hydrologic characteristics determination is especially
actual with relation to complexity of realization of hydrometric observations
during high water period on mountain rivers.
The necessity of further inquiry of
distinguished problems is caused by variety of natural factors, that determine
structural and dynamic peculiarities of mountain rivers. These factors not
adequately explored at present day.
The object of our investigations is the
process of forming of maximum runoff and riverbed deformations on the rivers of
Ukrainian Carpathians. The subject of our investigations are methods of
calculation of maximum water discharges in case of missing or insufficiency of
hydrometric observational data; fluviomorphological process of Ukrainian
Carpathian rivers and their riverbed formative water discharges. The main
methods of our investigations – in-situ observation of riverbed deformations,
analysis of hydrometric observational data, analysis of cartographic sources,
using of present-day methods of data processing (mathematical methods,
geoinformation technologies). Analysis of obtained data was executed with using
of results of in-situ measurements, theoretical and laboratorial investigations
of other authors. Scientific newness lies in using of in-situ measurements data
of riverbed formations for determining maximum water discharges. In particular,
formula for determination of lag velocity by parameter of riverbed type is
offered. Relation of weighted average value of riverbeds sediment diameter with
weighted average value of drainage area altitude for Carpathians region was
obtained. Possibility of using of bed-formation discharges for distinguishing
of calculated values of maximum downpour water discharges is supported.
Formulas for determining of value of bed-formation water discharge by riverbed
forms linear parameters have being received. Relations based on hydraulic
characteristics for typification of riverbeds, which can be used for
forecasting of possible riverbed deformations on Carpathians Rivers, are
offered. Estimation of evolution of riverbed deformation under the influence of
quarrying alluvial sediment is accomplished, based on data of long-term
observations. Basic conclusions by results of fulfilled researches come to
next.
Data of hydrometric observations on mounting
and submounting sections of rivers are not enough for engineering-hydrological
support of hydraulic construction. Hydrometric station damaging by high water,
changes of riverbed capacity under influence of quarrying out of alluvial
sediment causing deranging of representativeness of observational series.
Therefore studying of parameters of riverbed forms, created under influence of
floods is useful for subsequent determination of values of maximum water
discharges.
Weighted average value of riverbed sediment
diameter is one of the main parameters, that characterizes channels conditions
of floods passing. Peculiarities of
bedload transport regime and water runoff effect on determining conditions of
high water discharges forming. Quarrying of river sediment directly effects on
regime of rivers. It is discovered that developing of channel deformations,
caused by sediment excavation, keep on in the form of residual deformation. Energetic
characteristics, that determine kinematic structure of stream, used as criteria
of shaping of structural riverbed forms, allowed to separate channels by their
types definitely. That can be used for foreseeing of possible changes of
general scheme of riverbed deformations under hydraulic constructions and
quarrying of river sediment influence.
Lag velocity of flood surge is one of the main
parameters of genetic formulas for determining of maximum water discharges.
Calculations of maximum runoff with taking into account of fluviomorphological
process allowed to increase an accuracy of determination of values of maximum
water discharges in the whole.
Exposed regularities of forming of Carpathian
rivers bottom topography, obtained criterion of functional dependences of
riverbed types, specified parameters of formula of maximum water discharge and
calculation of bedload sediment transport in structured form create reliable
ground for quantitative assessment of maximum water discharges and riverbed
deformations for all tasks of design and operation of water-management systems
on the Ukrainian Carpathian rivers. That allows to raise reliability of
hydraulic structures in the whole.
Key words: high flow, lag velocity, weighted
average value of riverbed sediment diameter, bed-formation water discharge,
riverbed forms, channel deformations.
