Vibration diagnostics of thin sandwich shells

The work is concerned with the thin shells of the gas generators and power plants with strength-fastened sandwich in the functioning conditions on the test stand. The aim is to develop, investigate and introduce the vibration diagnostics of technical sandwich shell state and also to investigate the monitoring suitability of structures. The flaw detection methods of article with evaluating stressed-deformated state of structures have been developed on base of the vibration testing the sandwich shells. The methods for calculating parameters of the disturbing gas pressure influences in the sandwich channel have been developed. The special features of determining the damping characteristics of the cloth materials have been investigated. The experimental plants and new diagnostic method of sandwich shells have been proposed. The vibration diagnostics of sandwich shells has been introduced in Kirov NPAAvailable from VNTIC / VNTIC - Scientific & Technical Information Centre of RussiaSIGLERURussian Federatio

Railway diagnosis of electric transport

The increase in noise level at cities is increasing the requirements to functional interaction of road users - pedestrians and drivers - with the parameters of the environment as a leading component of Afferentation synthesis in the complicated complex of locomotive activity. City noise is one of the most widespread factors of unfavorable living and working conditions. The noise of high intensity provokes diseases, lowers labor activity. At present, many large cities pay much attention to electric vehicles. The authors present an analysis of the poor state of tram track in areas of high noise and vibration of car and under-sleeper base design. A negative effect of noise and vibration on the formation of urban areas environment is shown as well as the impact of these conditions on the person. The advantages of the application of electric transport are specified, noise displacement curve of railway and under sleeper base is plotted depending on the frequency of the applied load and the modulus of elasticity, as well as under sleeper base vibroacceleration depending on time. The authors offer a systematic study on the basis of a mathematical model of the sources of noise in the process of a tram motion

IMPLEMENTATION OF DIAGNOSIS AND REPAIR OF BRIDGE STRUCTURES

Insufficiency and delays of maintenance of the technical state of bridges is greatly related to work labour input, absence of adequate mechanical means and automation of the process of inspection of structures. The authors considered domestic and foreign Machinery which repair bridge structures and are used to conduct surveys, tests and special repairs on different levels, both above and below the vehicle position. The design of a machine with the main operational characteristics is presented. The defects detected during the inspection of bridges are enumerated. In the conditions of deterioration of the bridges of different structures and responding the requirements to reduce the risk level of engineering structures’ operation there is a demand in renewing the population of machines for investigation of the technical condition of automobile bridge, because of special vehicles deterioration, there is no staff of specialists who are able to solve the problems of maintenance and increasing the reliability of bridge structures to the required extend. Also the main principles of control and inspection of bridge structures include the requirements to technical equipment for measurements and testing equipment

DYNAMIC RESPONSE OF PAVEMENT SUBJECTED TO MOVING LOAD

The problem of dynamic equilibrium of the pavement under the action of moving load using ratios plane strain viscoelastic solid, resting on viscoelastic foundation is considered. By using finite difference method developed economical constitutive relation for numerical im- plementation of the problem. Approach to analysis in the frequency range is offered. Depend- ences of the road surface displacement amplitude on moving load speed for different values of foundation modulus are shown. Optimal speed of moving load is determined