Open AccessTowards the dynamic coefficient
Author(s) -
A. V. Kartopoltsev,
V. M. Kartopoltsev,
S. A. Kukhachenko
Publication year - 2021
Publication title -
vestnik tomskogo gosudarstvennogo arhitekturno-stroitelʹnogo universiteta
Language(s) - English
Resource type - Journals
eISSN - 2310-0044
pISSN - 1607-1859
DOI - 10.31675/1607-1859-2021-23-5-127-141
Subject(s) - inertia , vibration , stiffness , dynamic load testing , structural dynamics , mechanics , oscillation (cell signaling) , mode (computer interface) , stress (linguistics) , dynamic equilibrium , span (engineering) , damping ratio , dynamic stress , structural engineering , control theory (sociology) , dynamic loading , physics , classical mechanics , computer science , engineering , thermodynamics , chemistry , acoustics , biochemistry , linguistics , philosophy , control (management) , artificial intelligence , operating system
For the first time, this paper studies the fundamental conditions of the dynamics of bridge spans under non-stationary oscillations with regard to the mass inertia of the span–vehicle system. Based on the dynamic analysis of the stress-strain state of spans under changing live load, the mechanical and energy principles of additional dynamic load characterized by the dynamic coefficient, are formulated and substantiated. It is found that the dynamic coefficient slightly depends on the system vibrations due to the temporary nature of its application. The amplitudefrequency characteristics of the dynamic stress-strain state are considered in the mode of stable oscillations only. Theoretical and experimental studies of road bridges of various designs and lengths confirm the relationship between the dynamic coefficient and the parameters of damping and resonance. It is found that the dynamic coefficient reflecting the energy balance of the system allows considering the critical ratios of the equilibrium amplitudes and dynamic stiffness of the spans under the changing effect of the live load as well as the presence of road defects and span bearing elements in terms of the well-known Hurwitz criterion.