CN213240057U

CN213240057U - Expansion stress measuring device used after sample shrinkage deformation

Info

Publication number: CN213240057U
Application number: CN202021347848.9U
Authority: CN
Inventors: 杨彪; 刘伟
Original assignee: China Institute for Radiation Protection
Current assignee: China Institute for Radiation Protection
Priority date: 2020-07-10
Filing date: 2020-07-10
Publication date: 2021-05-18
Anticipated expiration: 2030-07-10

Abstract

The utility model relates to an expansion stress measuring device for after sample contraction deformation, including the base, the support of setting on the base has the over-and-under type cylinder cap on the support, has the sample chamber on the base, and the sample that awaits measuring is placed to the sample intracavity, and the top or the bottom in sample chamber install axial stress sensor, and radial stress sensor is installed in the global outside in sample chamber, and axial stress sensor and radial stress sensor passing signal line are connected with data acquisition system, are equipped with the water inlet and the delivery port that communicate with the sample chamber on the base. The device can obtain the axial and radial expansion force of the initial compacted sample under the initial sample volume after the initial compacted sample is subjected to shrinkage deformation, can truly reflect the influence of the action exerted on the compacted sample on the expansion force, realizes the real-time monitoring of the expansion force of the compacted sample of clay minerals when the compacted sample is subjected to shrinkage deformation under a certain action, and has high monitoring precision and efficiency.

Description

Expansion stress measuring device used after sample shrinkage deformation

Technical Field

The utility model belongs to the technical field of high radioactive waste geology is dealt with and specifically relates to an expansion stress measuring device that is used for after sample shrinkage deformation specifically is a device that radial and axial expansion stress real-time data acquireed after the deformation takes place for compaction bentonite piece.

Background

At present, the internationally accepted disposal of high-level radioactive waste (HLW) is deep geological disposal, which is designed based on multiple barrier principles. The cushioning material is the last artificial barrier in its design. Bentonite is widely selected as a buffering backfill material due to its good water-swelling capacity and nuclide adsorption capacity. In practical engineering, the cushioning material is required to have good ability to support and balance the peripheral pressure, which requires that the compacted bentonite should have moderate water swelling stress. Meanwhile, because the high-level radioactive waste has the characteristic of heat release, the buffer material tightly surrounding the waste is bound to be under the action of heat, and the buffer material loses water and is contracted and deformed under the action of heat (high temperature at the initial stage of treatment), so that the volume of the buffer material is reduced compared with that of an initial sample. The traditional expansion stress testing device can only test the stress value of a sample under the actual volume, and in the real disposal, the expansion force of the buffer material which is heated, dehydrated and contracted and is firstly expanded when absorbing water and is completely filled with the original volume is the real acting force to the outside. Therefore, in order to obtain the effect of thermal action on the expansion force, given the true expansion force of the sample after contraction by thermal action, improvements to existing testing devices are needed.

SUMMERY OF THE UTILITY MODEL

The utility model aims at solving the defect that prior art exists, provide an expansion stress measuring device that is used for after sample shrinkage deformation.

In order to realize the purpose, the utility model discloses a technical scheme as follows:

the utility model provides an expansion stress measuring device for after sample contraction deformation, includes the base, the support of setting on the base has the over-and-under type cylinder cap on the support, has the sample chamber on the base, the sample of awaiting measuring is placed to the sample intracavity, the top or the bottom installation axial stress sensor in sample chamber, radial stress sensor is installed in the global outside in sample chamber, axial stress sensor and radial stress sensor pass through the signal line and are connected with data acquisition system, be equipped with water inlet and the delivery port with sample chamber intercommunication on the base.

Furthermore, the base comprises an upper base and a lower base, wherein the opposite end faces of the upper base and the lower base are provided with grooves, and after the upper base and the lower base are spliced, the two grooves are butted to form a sealed sample cavity.

Further, the piston is connected to the bottom of over-and-under type cylinder cap, and the tip installation of piston the axial stress sensor, go up fixed mounting piston cover on the base, the inner chamber of piston cover with sample chamber intercommunication, the tip of piston stretches into in the piston cover, and the axial stress sensor of piston tip stretches into in the sample chamber, and the piston reciprocates in the piston cover and is suitable for controlling the height that sets up of axial stress sensor in the sample chamber.

Further, settle the permeable stone in the top recess of lower base, the permeable stone is located the bottom in sample chamber, water inlet and delivery port setting are in the bottom of permeable stone.

Further, the global department of contact of piston and piston sleeve, the global department of contact of piston and last base, the top surface edge of permeable stone all are equipped with the sealing washer.

Furthermore, the water inlet is connected with a water supply container with a pressure adjusting function through a guide pipe, and valves are arranged at the water inlet and the water outlet.

The utility model has the advantages that: the device can obtain the axial and radial expansion force of the initial compacted sample under the initial sample volume after the initial compacted sample is subjected to shrinkage deformation, can truly reflect the influence of the action exerted on the compacted sample on the expansion force, realizes the real-time monitoring of the expansion force of the compacted sample of clay minerals when the compacted sample is subjected to shrinkage deformation under a certain action, and has high monitoring precision and efficiency.

Drawings

Fig. 1 is a schematic structural view of the present invention;

figure 2 is high temple sub-bentonite expansion stress after the high temperature effect with conventional expansibility measurement system test and the utility model discloses the contrast picture of test result.

Detailed Description

As shown in figure 1, the device for measuring the expansion stress after the sample is contracted and deformed comprises a base, a support 1 arranged on the base, a lifting cylinder cover 2 is arranged on the support 1, a sample cavity 3 is arranged on the base, a sample to be tested is placed in the sample cavity 3, an axial stress sensor 4 is arranged at the top or the bottom of the sample cavity 3, a radial stress sensor 5 is arranged on the outer side of the periphery of the sample cavity 3, the axial stress sensor 4 and the radial stress sensor 5 are connected with a data acquisition system through signal lines, a water inlet 6 and a water outlet 7 which are communicated with the sample cavity are arranged on the base, the water inlet 6 is connected with a water supply container with a pressure adjusting function through a guide pipe, and valves are arranged at the positions of the water.

In order to facilitate sample placement and overall assembly, the base comprises an upper base 8 and a lower base 9, grooves are formed in the opposite end faces of the upper base 8 and the lower base 9, the upper base 8 and the lower base 9 are connected through bolts 10, and after the upper base 8 and the lower base 9 are spliced, the two grooves in the opposite faces of the upper base 8 and the lower base 9 are butted to form the sealed sample cavity 3.

In addition, the bottom of the lifting cylinder cover 2 is connected with a piston 11, the end part of the piston 11 is provided with an axial stress sensor 4, an upper base 8 is fixedly provided with a piston sleeve 12, the inner cavity of the piston sleeve 12 is communicated with the sample cavity 3, the end part of the piston 11 extends into the piston sleeve 12, the axial stress sensor 4 at the end part of the piston 11 extends into the sample cavity 3, and the piston 11 moves up and down in the piston sleeve 12 and is suitable for controlling the corresponding installation height of the axial stress sensor 4 in the sample cavity 3.

Further, a permeable stone 13 is arranged in a groove at the top of the lower base 9, the permeable stone 13 is positioned at the bottom of the sample cavity 3, and the water inlet 6 and the water outlet 7 are arranged at the bottom of the permeable stone 13. In order to ensure the sealing performance of the installation, the contact peripheral surface of the piston 11 and the piston sleeve 12, the contact peripheral surface of the piston 11 and the upper base 8, and the top surface edge of the permeable stone 13 are all provided with a sealing ring 14.

Further, the use method of the measuring device is as follows:

firstly, preparing a sample, namely preparing the sample with the diameter of 50mm and the thickness of 20mm by using a die and a press machine under certain pressure; then, performing high-temperature action on the prepared sample for a period of time, taking out the sample subjected to the heat action, and measuring the diameter, the thickness and the mass of the sample; placing a sample subjected to high-temperature action in a sample cavity 3 of an expansion chamber, placing a permeable stone 13 at the lower end of the sample, then placing a piston 11, an axial stress sensor 4 and a radial stress sensor 5, and then fastening an expansion chamber formed by an upper base 8 and a lower base 9 through bolts 10; the axial stress sensor 4 and the radial stress sensor 5 are connected with a data acquisition system through signal lines, and a water supply container is connected with a water inlet 6 through a conduit and then a test is started.

When the test is started, the pressure in the water supply container is increased to 100kPa, then the valve at the joint of the guide pipe is opened to inject the underground water, the water outlet 7 is opened, and after the gas in the water tank at the bottom of the sample cavity 3 is discharged, the water outlet 7 is closed. The sample of placing in the sample chamber 3 begins the inflation after absorbing water, uses data acquisition system to gather the data of axial and radial expansion stress in real time, when waiting that the data of gathering do not have obvious change in 10h, the end test, derives data, carries out data arrangement and analysis, obtains the high temple sub-bentonite expansion stress after the high temperature effect after the arrangement analysis test with conventional expansibility measurement system test and the utility model discloses the contrast map of test result is shown in fig. 2.

It can be known through the comparison, this device can obtain initial compaction sample after taking place shrinkage deformation, its axial and radial expansive force under initial sample volume, can truly reflect the effect of exerting on the compaction sample to its expansive force's influence, has realized the real-time supervision of its expansive force when clay class mineral compaction sample takes place shrinkage deformation under certain effect, monitoring accuracy, efficient.

The foregoing shows and describes the general principles, essential features, and advantages of the invention. It will be understood by those skilled in the art that the present invention is not limited to the above embodiments, and that the principles of the present invention may be applied to any other embodiment without departing from the spirit and scope of the present invention. The scope of the invention is defined by the appended claims and equivalents thereof.

Claims

1. The utility model provides an expansion stress measuring device for after sample contraction deformation, includes the base, the support of setting on the base has the over-and-under type cylinder cap on the support, a serial communication port, the sample chamber has on the base, the sample of awaiting measuring is placed to the sample intracavity, the top or the bottom installation axial stress sensor in sample chamber, the radial stress sensor of global outside installation in sample chamber, axial stress sensor and radial stress sensor pass through the signal line and are connected with data acquisition system, be equipped with the water inlet and the delivery port with sample chamber intercommunication on the base.

2. The device for measuring the expansion stress of the sample after the shrinkage deformation according to claim 1, wherein the base comprises an upper base and a lower base, the opposite end surfaces of the upper base and the lower base are provided with grooves, and after the upper base and the lower base are spliced, the two grooves are butted to form a sealed sample cavity.

3. The device for measuring the expansion stress after the contraction deformation of the sample according to claim 2, wherein a piston is connected to the bottom of the lifting cylinder cover, the axial stress sensor is installed at the end of the piston, a piston sleeve is fixedly installed on the upper base, the inner cavity of the piston sleeve is communicated with the sample cavity, the end of the piston extends into the piston sleeve, the axial stress sensor at the end of the piston extends into the sample cavity, and the piston moves up and down in the piston sleeve to control the setting height of the axial stress sensor in the sample cavity.

4. The apparatus according to claim 3, wherein a permeable stone is disposed in the groove at the top of the lower base, the permeable stone is located at the bottom of the sample cavity, and the water inlet and the water outlet are disposed at the bottom of the permeable stone.

5. The apparatus as claimed in claim 4, wherein the sealing rings are disposed at the contact surface between the piston and the piston sleeve, the contact surface between the piston and the upper base, and the edge of the top surface of the permeable stone.

6. The device for measuring the expansion stress of the sample after the shrinkage deformation according to claim 4, wherein the water inlet is connected with a water supply container with a pressure adjusting function through a conduit, and valves are arranged at the water inlet and the water outlet.