SU1153247A1 - Device for dynamic testing of buildings and structures - Google Patents

Abstract

A DEVICE FOR DYNAMIC TESTS OF BUILDINGS AND STRUCTURES, containing a base with an oscillation pathogen, characterized in that, in order to increase the reliability of operation and simplify the device, the oscillation pathogen is made in the vehicle with a load, two permanent magnets, inductive coils and spring stabilizers, and These magnets are rigidly fixed at opposite ends of the trolley coaxially with inductive coils rigidly attached to the base, and the trolley with a load is mounted on the base with the possibility of reciprocating of the downward movement and associated with it spring stabilizers. SP 00 th Jib.

Description

The invention relates to construction and is intended for dynamic testing of buildings of their fragments and large models. A device for dynamic testing of building structures is known, which comprises a troso-block system for resetting horizontally applied forces. The loss of this device is that it allows to conduct tests of buildings only in full size. Closest to the invention is a device for dynamically testing buildings and structures, containing a base with a C2 oscillation pathogen. However, in this device, the shafts of the vibrating machine used as the exciter, which are equipped with off-center loads, quickly wear out under the action of centrifugal forces, which reduces the service life of the machine. For building a directional action (usually horizontal) on the test building, the vibrator contains two shafts, which, firstly, leads to a complication of the design and increase in the cost of the machine, second, it creates pairs of forces with a shoulder equal to the distance between the shafts creating bending moments that periodically change their sign, and this leads to parasitic oscillations and additional wear. In addition, the presence of moving parts of shafts, bearings, gears brings additional parasitic oscillations during the test. The inertial forces excited on the vibrator shaft depend on the square of the rotation frequency, which adversely affects the testing of buildings in higher oscillation forms and makes it necessary to vary the mass of off-center loads using a set of debapans, since the radius of their rotation remains unchanged. In this case, every time you have to stop the vibrator. The purpose of the invention is to increase the reliability and simplify the device. The goal is achieved by the fact that in the device for dynamic testing of buildings and structures containing a base with a vibration exciter, the vibration exciter 47 is made in the form of a trolley with a load, two permanent magnets, inductive coils and spring stabilizers, and the permanent magnets are rigidly fixed at opposite ends of the trolley coaxially with inductive coils rigidly attached to the base, and the trolley with the load is mounted on the base with the possibility of reciprocating motion and connected with it by a spring nnym stabilizers. The drawing shows a device for Dynamic testing of buildings and structures, a general view. The device contains a base 1 fixed on the test building 2, a trolley 3 and inductive coils 4 mounted on the base, permanent magnets 5 mounted on a trolley, spring stabilizers 6, weights 7 and a generator 8. The device works as follows. The sinusoidal current of the required frequency from the generator 8, the passage through the successively connected windings of the coils 4, creates in them a sinusoidal magnetic field, which, interacting with the magnetic field of the permanent magnets 5, results in a pull in the coil and a repulsive force in the other directed along the axis of the coils, sinusoidally varying in magnitude with a frequency equal to the frequency of the current at the output of the generator 8. Under the action of these forces, there is a reciprocating movement of the carriage 3 with fixed on it, magnets 5 along the base, thanks to the inertial forces arising from this, proportional to the mass of the trolley 3c with loads 7, and the rigid attachment of the base to the building 2 being tested, the latter starts to oscillate with a frequency equal to the frequency of the trolley movement. The magnitude of the inertial forces depending on the test program for each fixed frequency can be varied by changing the amplitude of the back and forth motion of the carriage by changing the power of the electrical signal applied to the inductive coils 4, as well as by changing the mass of the loads mounted on the carriage.

311532474

The proposed device differs in the process of testing buildings and

simplicity of design and control of structures according to higher forms of oscillation. There is almost no

the possibility of occurrence of any In addition, the proposed device

parasitic vibrations. There is a high reliability in

It is possible to vary as a mass work, since it practically

cargo and amplitude move-there are no parts working under

nor a trolley, which is significantly relieved by forceful action.

Claims (1)

DEVICE FOR DYNAMIC TESTS OF BUILDINGS AND STRUCTURES, containing a base with a vibration exciter, characterized in that, in order to increase the reliability and simplify the device, the vibration exciter is made in the form of a trolley with a load, two permanent magnets, inductive coils and spring stabilizers, and constant magnets are rigidly fixed at opposite ends of the trolley coaxially to inductive coils rigidly attached to the base, and the trolley with cargo is mounted on the base with the possibility of reciprocating motion and is connected with it by spring _Λ stabilizers. (L