RU71768U1 - INSTALLATION FOR DETERMINING THE DYNAMIC ELASTIC MODULE OF BITUMINOMERAL MATERIALS UNDER THE INFLUENCE OF SHORT-TERM LOAD - Google Patents

Abstract

Installation for determining the dynamic elastic modulus of bitumen-mineral materials under the influence of short-term loads, containing a pressure unit on the sample is a climatic chamber for setting the test temperature, in which the control panel of the climatic chamber is mounted, a node for fixing the test sample, the pressure unit on the sample, made in the form a pneumatic cylinder with a pressure regulator, on which there is a mechanical load transducer with a sensor, plunger and device, before the vertical load on the sample along the generatrix, and the measuring device is displacement sensors installed on both sides horizontally along the generatrix of the sample in one plane passing through its center, sensors of the transducer of mechanical load and temperature, which are connected via electronic cables to the electronic control unit and information processing with the ability to display information and process it on a computer.

Description

The utility model relates to testing equipment and can be used in testing the design, deformation characteristics of bitumen-mineral materials. A device for compression testing (RU 2163715) is known, which relates to means for testing materials and can be used to measure the modulus of elasticity and strength of non-metallic materials. The device is a camera in the form of a glass for placement of a test sample in it, a punch and measuring sensors, an information unit that receives signals from sensors.

However, such a test device is not effective enough, since during the test, in addition to compressing the sample, the elastic deformation of the punch over its entire height is taken into account, which leads to distorted readings and a decrease in the reliability of the test results.

By the number of common features and the achieved result, the closest device to determine the elastic modulus of asphalt concrete is closest to the claimed technical solution. (Instructions for the design of pavements of non-rigid type "Ministry of Transport, VSN 46-83, Moscow" Transport ", 1985, S.141-142.)

Test the samples in the laboratory room, maintaining the temperature of the sample with electric heaters. The load on the sample prepared in accordance with the requirements of standard procedures is transferred from the lever press through a steel stamp, a dial indicator attached to the stand is placed under the sample for

determination of vertical displacement (deflection). The sample is tested twice, the readings of the indicators are taken at the end of loading and at the end of rest, and then the reversible vertical movement (in centimeters) of the stamp is calculated by the difference in counts, constantly checking the rigidity of the indicators by lightly tapping a metal object along the edge of the form. Moduli of elasticity (in megapascals) are calculated by the formula. Having the values of the elastic modulus of asphalt concrete, determine the elastic modulus of the material working in conditions close to natural.

The main objective of the utility model is to create a device that allows to increase test efficiency, accuracy and reliability of readings due to the possibility of measuring small linear displacements in static and dynamic modes, in the efficiency of measurements and processing of measurement results.

The technical result is achieved by the fact that the installation for determining the dynamic elastic modulus of bitumen-mineral materials under the influence of short-term loads, containing a pressure unit on the sample and a measuring device, is a climatic chamber in which a control panel for the climatic chamber is mounted to set the test temperature, a unit for fixing the sample for tests, the pressure unit on the sample, made in the form of a pneumatic cylinder with a pressure regulator, on which there is a transform mechanical load generator with a sensor, plunger and device transmitting the vertical load on the sample along the generatrix, and the measuring device is displacement sensors installed horizontally on both sides along the generatrix of the sample in one plane passing through its center, sensors of the mechanical load and temperature transducer, which are connected via connecting cables to the electronic control and information processing unit, which converts the signals of the measurement information about the measured values controlled samples, displaying their digital value on the display with the ability to display information and process it on a computer.

The technical solution for determining the dynamic elastic modulus of bitumen-mineral materials under the influence of short-term loads is based on the principle of recording the changing linear parameters of the control object (sample) under the influence of loads (mechanical forces).

The electronic control and information processing unit, consisting of measuring and information units, is designed to measure small, slowly and rapidly varying linear parameters of the sample, deviations from the nominal linear size of the controlled sample, as well as to measure the mechanical forces acting on the control object and the ambient temperature and displays a digital value about the measured values of the controlled sample on the display with the ability to process these values on a computer.

The presence of an electronic control unit and processing the results, receiving signals from the sensors, can improve the efficiency of the device by quickly receiving test results in the form of a test schedule and digital values.

The drawing shows a General view of the installation for determining the dynamic modulus of elasticity of bitumen-mineral materials under the influence of short-term loads. The installation for determining the dynamic modulus of elasticity of bitumen-mineral materials under the influence of short-term loads includes a climate chamber 1, a unit for fixing a test sample 2, displacement sensors 3, a temperature sensor 4, a pneumatic cylinder with a pressure regulator 5, a mechanical load transducer with a sensor 6, a plunger 7, a device transmitting the vertical load on the sample 8, the control panel of the climate chamber 9, the electronic control unit and information processing 10.

The principle of operation of the installation is based on a preliminary short-term mechanical action (loading) on the test sample and measurement of its linear dimensions.

The electronic control and information processing unit can operate in four modes:

- Parameters - for measuring the initial values of the measured values of the load and the temperature in the test chamber;

- Preliminary compression - for a number of preliminary tests to make sure that they are flowing correctly;

- Test - to establish the number of measurements;

- Remote control - to control the test process and obtain results remotely using a PC at a distance via the RS 232 interface.

The choice of the temperature mode of operation is made using the buttons located on the front panel of the climate control panel.

The installation works as follows: the test sample is installed in the climatic chamber 1 for testing in the mounting unit 2. On the upper surface of the sample, a device is installed that transfers the vertical load to the sample 8 connected to the pneumatic cylinder with pressure regulator 5 through the plunger 7 and the mechanical load transducer 6. From two sides horizontally along the generatrix of the sample in one plane passing through its center, set the displacement sensors 3. On the remote control of the electronic control unit and processing inf rmatsii 10 set one of four modes, e.g., test mode.

When a load is applied through a pressure unit consisting of a pneumatic cylinder with a pressure regulator 5, a plunger 7, a mechanical load transducer with a sensor 6, a device transmitting a mechanical load 8, the sample is deformed, two displacement sensors 3, which are in direct contact with the deforming surface of the sample, perceive linear movements and generate an electrical signal. The signals from the linear displacement sensors 3, as well as from the sensors of the mechanical load transducer 6 and temperature 4, are supplied to

electronic control and information processing unit 10, where they are processed, stored, and output of measurement results to the electronic display in the form of a digital code. A computer with appropriate software is connected to the output of the electronic unit.

In this case, no additional time is required for taking readings and processing the test results. Readings and their processing are carried out automatically. During the loading of the sample, a test schedule is drawn on the monitor screen and the value of the dynamic elastic modulus of bitumen-mineral materials under the influence of the load is displayed.

Sources used

1. RF patent №2163715, Cl. G01N 3/08, publ. 2001.02.27.

2. (Instructions for the design of pavements of a non-rigid type "Ministry of Transport, VSN 46-83, Moscow" Transport ", 1985, S.141-142.) (Prototype)

Claims (1)

Installation for determining the dynamic elastic modulus of bitumen-mineral materials under the influence of short-term loads, containing a pressure unit on the sample and a measuring device, characterized in that the installation is a climate chamber, in which a control panel for the climate chamber is mounted to set the test temperature, a unit for fixing the test sample , the pressure unit on the sample, made in the form of a pneumatic cylinder with a pressure regulator, on which there is a fur converter load with a sensor, a plunger and a device that transmits the vertical load on the sample along the generatrix, and the measuring device is displacement sensors installed on both sides horizontally along the generatrix of the sample in the same plane passing through its center, sensors of the transducer of mechanical load and temperature, which through connecting cables are connected to an electronic control and information processing unit with the ability to output information and process it on a computer.