SU978007A1 - Device for material specimen yclic testing in volume-stressed state - Google Patents

Description

one

The invention relates to the study of the strength properties of materials, namely, devices for cyclic testing of materials in the bulk stressed state, and can be fade. Used to study rock deformations under cyclic loading.

Known devices for cyclic. testing materials that contain hydro pulsators with traction, repulsive Q s load on the sample T11.

The disadvantage of these devices is that in order to create a synchronous cyclic load on a sample under a volumetric stress state, when one, j taking the components of the tensor of tensions not two others, these devices need to be connected to an additional hydropulsator.

The closest to the proposed by the technical essence is a device for cyclic testing of samples of materials with a tight load.

a state containing a high pressure gauge to accommodate a test | sample, installed in a piston and specimen grips, and an exciter associated with the piston. In addition, with a synchronous load and pressure change circuit, the device contains a second piston, and the chamber cavity is stepped, and the areas of the pistons are different C23.

Claims (2)

The disadvantages of the known device are the inability to replace the ratio between the component and the tensor of the vacuum. Indeed, the ratio between the axial in the lateral, and the group of sites is determined by the ratio between the areas of the upper and lower and amp; go kyurshney, which is a constant for this camera. Along with this, for a number of problems of a mechanically deformable body, in particular for rock mechanics, the results of research are of great variability in the variation between the components of the stress tensor, which is a reflection of the effect of stress in the mountain range. rocks as the transition from the contour into the array. Since, in the known device, the axial load is created by compressing the sample to the upper pistons and the lower pistons, only one sample can be placed in the chamber (different samples, at least rocks, do not allow several samples to be installed between the pistons at a time). state of stress. This reduces the performance of the test. The purpose of the invention is to expand the functionality of the device by changing the ratio between the components of the stress tensor. The spruce is achieved by the fact that the device for cyclic testing of material samples is equipped with a rigid frame placed in the pressure chamber and co-axially mounted piston and filled with adjustable quantity of liquid syphons with which the specimen grips are connected. The drawing shows the circuit of the proposed device. 1 and 2 mounted coaxially in a rigid frame 3, connected to the bellows 1 and 2 grips 4 and 5, in which the primer 6 of the test material is installed, a high pressure chamber 7 in which p zmesheny said elements and the piston 8, koto ing through rod 9 is connected to the energizer (not shown). The pressure chamber 7 is connected via a rod 10 to an energizer or a fixed traverse test machine (not shown). It is preferable to use a fatigue testing machine hydraulic actuator. Each W3 bellows 1 and 2 has a device 11 for filling the bellows with a controlled amount of liquid. The device works as follows. The energizer using a piston 8 creates a pulsating pressure of the fluid in chamber 7. This pressure is the side pressure for sample 6. The pressure in chamber 7 causes the bellows 1 and 2 to deform along the axis of sample 6 and create pressure in the fluid inside the bellows 1 and 2. The pressure of the fluid inside the bellows 1 and 2 is different from the pressure of the fluid in the chamber 6. The pressure is determined by the pressure-free volume of each of the bellows. The amount of load required to deform the bellows is governed by the amount of fluid placed inside the bellows. Since the pressure inside the bellows creates an axial load on the sample 6, changing the amount of fluid inside the bellows 1 and 2 is a means of changing the ratio between axial and lateral loads of sample 6. This ratio can vary in the proposed device over a wide range as by changing the amount of liquid in the bellows, and by selecting the stiffness and size themselves. bellows. The range of variation of the axial component of the stress tensor ranges from zero (with empty rigid bellows) to the value of the side components of the stress tensor (with fully compliant bellows completely filled with liquid). The proposed device allows varying the ratio between the components of the stress tensor over a wide range. This circumstance makes it possible to efficiently use a device for solving broad problems of rock mechanics, where it is of interest to change one of the components of the stress tensor from zero (for the contour of the array) to the Stress state of hydrostatic compression (in the depth of the array). The advantage is the ease of changing the characteristics of the device, not conforming to design changes. In addition, test performance is improved by simultaneously testing several samples in a single high pressure chamber. For cyclic tests associated with a long duration of the experiment, the simultaneous testing of several samples several times increases the capacity of the equipment and, moreover, ensures the similarity of the test conditions of the series of samples. Claims J Apparatus for cyclic testing of material samples in bulk stress state, comprising a high pressure chamber for accommodating a test specimen, a piston installed therein and specimen grips and an exciter associated with the piston, characterized in that