ES1078585U - Exciter to induce vibrations in railway infrastructure (Machine-translation by Google Translate, not legally binding) - Google Patents

Abstract

Exciter to induce vibrations in railway infrastructure, characterized by being constituted by counter-rotating masses (1). (Machine-translation by Google Translate, not legally binding)

Description

EXCITATOR TO INDUCE VIBRATIONS IN INFRASTRUCTURE RAILWAY

OBJECT OF THE INVENTION

The present invention relates to a powerful and transportable dynamic exciter, mounted on a car designed specifically for such use that, by rotating vertically rotating masses with variable turning radius (arm) and speed, allows the transmission of intensity vibrations and variable frequency to the railway infrastructure.

BACKGROUND OF THE INVENTION

One of the factors that has the most influence on the dynamic response of the bridges and on which, in a certain paradoxically way, more uncertainties exist, is structural damping. Dynamic calculation models provide forecasts of the structural response (deformations, vibrations) that strongly depend on the value of structural damping used in the model. Complex models of the structures, capable of reproducing their three-dimensional behavior, produce calculations that influence a high number of vibration modes, whose contribution to the response may be excessive if they are assigned a damping rate that is too conservative or on the side of the security. This is a common practice today because of the lack of knowledge of the actual damping rates in higher modes of vibration, and although this practice is generally accepted because it is considered to be on the side of safety, there is no real assessment, reliable studies. , on whether this degree of conservatism can be adequate or (on the contrary) excessive in dynamic calculations of viaducts for high speeds (up to 350 km / h) and very high (higher than 350 km / h).

For this purpose, it is very interesting to have an exciter system to induce vibrations in the viaducts of intensity comparable to the passage of the trains, but that allows to perform the experimental modal analysis with a controlled excitation in different points of the structure. The possibility of carrying out multiple tests to better understand the mechanisms of structural damping is, therefore, of great interest and practical importance. Such an apparatus would be very useful for obtaining damping rates of multiple vibration modes, at amplitudes similar to those produced by the passage of railways. This would improve the methods that are currently used, which are based on (1) environmental excitations (mainly wind) of very low amplitude, so that the structure deforms very little and not all its energy dissipation mechanisms are activated , or (11) free vibrations caused by the passage of railroads, which are of very short duration and normally do not excite in the same way all the vibration modes of interest (it is even usual to have to complement the sampling time of the free vibrations with a later interval of environmental excitation in order to obtain reliable information about the different vibration modes).

The instruction on technical inspections in railway bridges (ITPF-05) sets the standards to be followed in the mandatory load tests for new construction. In this sense, he points out that all bridges will always carry out load tests that reproduce the most unfavorable load states and that these will be static and dynamic at different speeds. According to ITPF-05, dynamic tests should be performed at speeds close to the resonance speed, which would be the most unfavorable situation in terms of dynamic response of the structure. However, the maximum constant speed that can be achieved taking into account the safety requirements of load tests is normally between 60 and 100 km / h. These speeds will be in many occasions far from the resonant speeds, which could be close to the maximum speed of the line, which for the purpose of dynamic testing takes twenty percent higher than the project speed, and that in the new lines of High speed can be up to 420 km / h. An exciter device of this type would be very useful to be used in load tests in order to achieve a dynamic excitation of an intensity comparable to that produced by the train at resonant speeds, which would be of great help at the time of Reception of the structure complying with the spirit of the regulations, which is so difficult to achieve today. In the same way it would be very useful in carrying out load tests in structures in service, with a double objective: (1) to expand the knowledge of the state of the structure by evaluating its dynamic response, either periodically or as a result of inspections specials that so advise after detection of damage in basic inspections; (I1) in the case of conditioning lines to new operating conditions, both in terms of loads (passage of exclusive passenger traffic to mixed traffic) and in terms of speeds (conditioning for higher operating speeds).

DESCRIPTION OF THE INVENTION

The exciter consists of a series of vertically rotating masses (1) vertically, around a common horizontal axis (2), with suitable motors and actuators to allow varying both the distance to the axis (swing arm, 3) and the speed of rotation (4) of the masses.

The value of the masses, the range of variation of the swing arm and its speed, will be a function of the type of infrastructure to be analyzed by applying the exciter, taking into account the load and frequency requirements for the excitation. The engine design will adapt to these needs.

The exciter apparatus must be mounted on a railway car (5) designed for this purpose to be able to transport it through the tracks. Additionally, it will have a pneumatic equipment (6) that allows the direct transmission of vibrations to the infrastructure, independently of the wagon rolling equipment, through false wheels (7). This is necessary to avoid wear on the rolling elements and to avoid the loss of excitation energy in the suspension elements of the car (suspension dampers).

The equipment is completed with the appropriate software and control hardware for the variation of intensity and frequency of the excitation, through the variation of speed and swing arm.

Finally, the equipment will be equipped with the necessary load control elements to know at any moment the force actually transmitted to the infrastructure, using sensors

(8) placed in the actuators on the infrastructure.

BRIEF DESCRIPTION OF THE FIGURES

Figure 1 shows a diagram of the exciter. It represents the fundamental elements that make up the exciter, that is: vertically counter-rotating masses (1) common horizontal axis of rotation of the counter-rotating masses (2), mechanical principle of variation of the eccentricity of the masses (3) mechanical principle of variation of the speed of rotation of the masses (4) railway car designed for this purpose to be able to transport the exciter through the tracks (5) pneumatic equipment that allows the direct transmission of vibrations to the infrastructure (6) transmission system Directly from the vibrations to the infrastructure independently of the wagon rolling equipment, through false wheels (7) load control elements by means of sensors placed in the actuators on the infrastructure (8).

PREFERRED EMBODIMENT

The preferred embodiment, as can be seen in the attached figure,

it will consist of the assembly on a railway car (5) of a generator device

vibrations constituted by counter-rotating masses (1) that rotate by means of a horizontal axis

(2) to which they are joined by fasteners that allow varying the eccentricity of the masses and driven by motors (4) that allow varying the rotation speed of

the masses The vibrations generated will be transmitted to the track by means of a pneumatic device (6) that, through false wheels (7), allows the vibrations to be transmitted directly to the track independently of the carriage system. Finally, it will incorporate a software for controlling and measuring the force and vibration exerted from the sensors placed for this purpose placed on the actuators on the track (8).

Claims (1)

1.-Exciter to induce vibrations in railway infrastructure, characterized by being constituted by counter-rotating masses (1). 2.-Exciter to induce vibrations in railway infrastructure, in accordance with the Claim 5, characterized in that the axis of rotation of the counter-rotating masses (2) is horizontal (rotation in vertical planes). 3.-Exciter to induce vibrations in railway infrastructure, according to claim la, characterized in that the turning radius (arm, 3) and speed (4) are variable and controllable by means of the appropriate control equipment. 4. Exciter to induce vibrations in railway infrastructure, according to claim la, characterized by being mounted on a railway car (5). 5.- Exciter to induce vibrations in railway infrastructure, according to the la, characterized in that the wagon on which it is mounted has a hydraulic equipment (6) capable of transmitting the excitation to the infrastructure directly, without going through the 15 wagon rolling system, through false wheels (7). 6.-Exciter to induce vibrations in railway infrastructure, according to claim la, characterized by being mounted on a tire vehicle. 7.-Exciter to induce vibrations in railway infrastructure, according to claim 1, characterized in that the tire vehicle on which it is mounted 20 has a hydraulic equipment capable of transmitting the excitation to the infrastructure directly, without going through the vehicle's rolling system, through false wheels. 8.-Exciter to induce vibrations in railway infrastructure, according to claim la, characterized by having a load control equipment (8) by sensors placed in the actuators on the infrastructure. FIGURE  ~ D ~ D ~ D ~ D ~ D ~ D ~ D ~ D ~ D ~ D ~   oo ~ oo ~ oo ~ 00 ooooooooo 00 ~ oo ~ oo ~ oo ~ 00 ° ~ o oePo OO °, .. D 00 °, .. D oePo oePo, .. o oePo & bn- .. & b & bn- .. ° 00 n- .. ° 00 & t & o ~ ° 00 & b 00 o o go go o o go o ~ oo o-V oo oo o-V o-V o o 00 o o o o o o o 00 o o 00 o o o o 00 o o 00 ° o o 00 o o o o o o 00 o o o o o o