CN114397433A - Test method for service of shape memory alloy recovery asphalt pavement deformation research - Google Patents
Test method for service of shape memory alloy recovery asphalt pavement deformation research Download PDFInfo
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Abstract
The invention belongs to the technical field of road engineering, and particularly relates to a test method for service shape memory alloy recovery asphalt pavement deformation research, which comprises the following steps: alternately laying asphalt concrete and a plurality of shape memory alloy wires in a sample forming mould, arranging asphalt concrete layers adjacent to the top and the bottom of the sample forming mould, and forming and demoulding according to a conventional procedure after the sample forming mould is filled up to prepare a test sample strip with a preset size; bending the test sample strip from two ends to the middle to a preset deformation rate in a temperature environment higher than the phase transition temperature of the shape memory alloy wire, and cooling and shaping in a temperature environment lower than zero centigrade; the invention aims to provide a test method for researching the deformation of a service shape memory alloy recovery asphalt pavement, which is comprehensive in system and simple to implement.
Description
Technical Field
The invention belongs to the technical field of road engineering, and particularly relates to a test method for service shape memory alloy recovery asphalt pavement deformation research.
Background
Under the action of multiple factors such as weather conditions, driving load and the like, the asphalt pavement can deform and even be damaged by fatigue. Therefore, the research and application of the rapid, efficient and less-interference technology or the technology for repairing the asphalt pavement has become one of the research directions in the field of road engineering in recent years. In recent years, a few of domestic researchers have begun to apply shape memory alloy materials with a deformation recovery function to asphalt pavements in order to recover asphalt pavement deformation, repair asphalt pavement diseases and the like. However, there is currently no uniform, standardized test method for the application of shape memory alloys to asphalt pavement research.
Disclosure of Invention
In view of the above technical problems, the present invention aims to provide a test method for performing a simple service on the deformation research of the shape memory alloy restored asphalt pavement, wherein the test method is comprehensive in system.
In order to achieve the purpose, the technical scheme adopted by the invention is as follows:
a test method for service shape memory alloy recovery bituminous pavement deformation research comprises the following steps: alternately laying asphalt concrete and a plurality of shape memory alloy wires in a sample forming mould, arranging asphalt concrete layers adjacent to the top and the bottom of the sample forming mould, and forming and demoulding according to a conventional procedure after the sample forming mould is filled up to prepare a test sample strip with a preset size; bending the test sample strip from two ends to the middle to a preset deformation rate in a temperature environment higher than the phase transition temperature of the shape memory alloy wire, and cooling and shaping in a temperature environment lower than zero centigrade; and testing the deformation recovery condition of the test sample strip by using a shape memory alloy wire clamped by the test sample strip after the bending processing is electrically triggered.
In some embodiments, the test strip is subjected to a bending process that meets one or more of the three criteria of micro-deformation, large deformation, and micro-crack deformation.
In some technical schemes, the deformation rate of the micro deformation of the test sample strip is 1% -2%; the deformation rate of large deformation is 2-8%; and the micro-crack deformation is the deformation rate when micro-cracks just appear in the bending process of the test sample strip.
In some technical schemes, the deformation rate of the test sample strip during the bending process when micro deformation, large deformation and micro-crack deformation occur is calculated by adopting the following formula:
wherein, deltaiIs the deformation rate; l0Is formed by bendingTesting the initial length of the sample strip before bending deformation; liFor testing the length of the strip after bending deformation, said0And liThe unit of (A) is: mm.
In some technical schemes, the deformation recovery condition of the test sample strip is tested by using a shape memory alloy wire clamped by the test sample strip after electric trigger bending processing, and the test instrument is electrically connected with the end parts of the shape memory alloy wire extending out of the two ends of the test sample strip through electric pulse test wires.
In some embodiments, the energizing current of the test instrument satisfies the following equation:
c is the specific heat constant of a single shape memory alloy wire and is 535J/kg.K;
s is the area of the end face of a single shape memory alloy wire, and the diameter of the end face of the shape memory alloy wire is 1.5 multiplied by 10-4m；
Rho is the density of a single shape memory alloy wire and is 6500kg/m3；
The delta T is the difference value between the ambient temperature and the temperature for triggering the shape memory alloy wire to exert the deformation recovery action, and the unit is;
epsilon is the resistivity of a single shape memory alloy wire and is 0.8 multiplied by 10-6Ω·m；
t is the energization time in units of s.
In some technical schemes, the plurality of shape memory alloy wires are uniformly distributed to a plurality of groups in the die length direction at intervals, and after demolding, linear cutting is carried out along the central line between two adjacent groups to prepare a plurality of test sample strips with preset sizes.
In some technical schemes, the spacing distance between adjacent groups is 10-20mm, four shape memory alloy wires are distributed in any group, the total length of the test sample strip extending out of two ends of each shape memory alloy wire is 40-100mm, and the end parts of each group of shape memory alloy wires are flush.
In some technical schemes, the test sample bar is a cuboid, and the length before bending processing is between 100 and 160mm, the width is between 20 and 40mm, and the height is between 20 and 50 mm.
In some technical schemes, the asphalt concrete is prepared by mixing and stirring aggregate and asphalt, and the particle diameter of the aggregate is not higher than 10 mm.
The invention adopts the technical scheme and at least has the following beneficial effects:
1. designing a multi-link comprehensive test system comprising spline preparation, deformation processing and a trigger mechanism to form a unified and standard test method for applying the shape memory alloy to asphalt pavement research;
2. the asphalt concrete and the shape memory alloy wires are alternately laid in the sample forming die to form the test sample strips with stable structures, and in some technical schemes, a plurality of test sample strips are prepared at one time in an interval laying mode, so that the operation is simple, and the preparation efficiency is improved;
3. the deformation processing technology of high-temperature bending deformation and low-temperature shaping is adopted, the implementation is simple, and in some technical schemes, the bending processing completion standard is provided: micro deformation, large deformation and micro crack deformation, and designing a calculation formula and a threshold range aiming at the deformation rate;
4. the deformation recovery condition of the test spline is tested by adopting an electric trigger mechanism, the cost is saved, the operation is convenient, in some technical schemes, a calculation formula of an electric trigger current value is also provided, and the test result is accurate and reliable.
Drawings
In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings and the reference numerals thereof used in the embodiments are briefly described below, and it is obvious that the drawings described below are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained based on these drawings without creative efforts.
FIG. 1 is a schematic plan view of an electrical triggering mechanism according to an embodiment of the present invention;
FIG. 2 is a schematic side view of a test bar according to an embodiment of the present invention;
FIG. 3 is a schematic view of the arrangement of shape memory alloy wires in a sample forming die according to an embodiment of the present invention;
fig. 4 is a schematic diagram of the deformation degree of the test bar according to the embodiment of the present invention.
The notations in the figures have the following meanings:
10-test bars; 20-shape memory alloy wire; 30-a test instrument; 40-electrical pulse test line; 50-sample forming die; 61-micro deformation; 62-greater deformation; 63-microcrack deformation occurred.
Detailed Description
In order to make the technical features, objects and effects of the present invention more clearly understood, a detailed description of embodiments of the present invention will be given below with reference to the accompanying drawings.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.
The shape memory alloy material is a functional material with shape memory effect, and is widely applied to the fields of spaceflight, machinery, electronics, medical treatment, daily life and the like. The method is based on the application of the shape memory alloy material in the deformation recovery of the asphalt pavement, a multi-link comprehensive test system comprising spline preparation, deformation processing and a triggering mechanism is designed, and a unified and standard test method is formed.
Referring to fig. 2 and 3, in one embodiment, the specific operation steps for preparing the sample strip are shown, which include:
s1, mixing the asphalt concrete by adopting a conventional mixing process, and uniformly paving half of all asphalt concrete materials in the sample forming mold 50;
the asphalt concrete is prepared by mixing and stirring aggregate and asphalt, and the particle diameter of the aggregate is less than or equal to 10 mm; the sample forming die 50 had a length of 300mm and a width of 150 mm.
S2, distributing the shape memory alloy wires 20 to the length direction of the sample forming die 50 in a mode of arranging a plurality of groups at intervals, wherein any group comprises four shape memory alloy wires 20 which are uniformly distributed at intervals in the range of 20-30mm in the die length direction, the total length of a test sample strip 10 extending out of two ends of each shape memory alloy wire 20 is 40-100mm, the end parts of each group of shape memory alloy wires 20 are flush, and the interval distance between adjacent groups is 10-20 mm;
s3, after the shape memory alloy wires 20 are arranged, filling the sample forming die 50 with the rest half of the asphalt concrete material and forming according to the conventional process;
and S4, after the sample is molded, the sample is released from the mold and is linearly cut along the middle of two adjacent groups of shape memory alloys symmetrically, and the whole sample is processed into the test sample strip 10 meeting the preset size.
It should be noted that the test specimen 10 is a rectangular parallelepiped, and the length before bending is between 100 and 160mm, the width is between 20 and 40mm, and the height is between 20 and 50 mm.
In this embodiment, a test sample bar 10 having a stable structure is formed by alternately laying asphalt concrete and laying shape memory alloy wires 20 in a sample forming mold 50; a plurality of test sample strips 10 are prepared at one time by adopting a mode of interval arrangement, the operation is simple, and the preparation efficiency is improved.
Referring to FIG. 4, in another embodiment, the deformation processing of the sample bars tested in the present application is shown in a plurality of shapes, namely micro-deformation 61, large deformation 62 and micro-crack deformation 63. The specific operation mode is as follows: and (3) bending the prepared test sample strip 10 from two ends to the middle to a preset deformation rate in a temperature environment higher than the phase transition temperature of the shape memory alloy wire, quickly cooling and shaping the bent and deformed test sample strip 10 in a temperature environment below zero centigrade for at least 10min, and further obtaining the bent and deformed test sample strip 10 for testing.
In a preferred embodiment, the test bars 10 have a micro-deformation rate of 1% to 2%; the deformation rate of large deformation is 2-8%; the occurrence of the micro-crack deformation is a deformation rate at which micro-cracks just occur during the bending process of the test specimen 10.
The application also provides a specific calculation formula of the deformation rate:
wherein, deltaiIs the deformation rate; l0The initial length of the test specimen before bending deformation; liFor testing the length of the specimen after bending deformation,/0And liThe unit of (A) is: mm.
In the embodiment, the deformation processing technology of high-temperature bending deformation and low-temperature shaping is adopted, the implementation is simple, and the standard of bending processing completion is provided: micro deformation 61, large deformation 62 and micro crack deformation 63, and a calculation formula and a threshold range are designed according to the deformation rate.
Referring to fig. 1, in another embodiment, a specific configuration of the triggering mechanism is shown, which includes a testing instrument 30, the testing instrument 30 is electrically connected to the ends of the shape memory alloy wires 20 extending out of the two ends of the test spline 10 through electric pulse testing wires 40, and a certain pulse signal is applied to the ends of the shape memory alloy wires through the current conducted by the testing instrument 30, so as to test the deformation recovery condition of the bending deformation shape memory alloy to the test spline 10.
In a preferred embodiment, the calculation formula of the energizing current of the testing instrument is specifically given as follows:
c is the specific heat constant of a single shape memory alloy wire and is 535J/kg.K;
s is the area of the end face of a single shape memory alloy wire, and the diameter of the end face of the shape memory alloy wire is 1.5 multiplied by 10-4m；
Rho is the density of a single shape memory alloy wire and is 6500kg/m3；
The delta T is the difference value between the ambient temperature and the temperature for triggering the shape memory alloy wire to exert the deformation recovery action, and the unit is;
epsilon is the resistivity of a single shape memory alloy wire and is 0.8 multiplied by 10-6Ω·m；
t is the energization time in units of s.
In the embodiment, an electric trigger mechanism is adopted to test the deformation recovery condition of the test spline 10, the cost is saved, the operation is convenient, a calculation formula of an electric trigger current value is provided, and the test result is accurate and reliable.
The method designs a multi-link comprehensive test system comprising spline preparation, deformation processing and triggering mechanisms based on the application of the shape memory alloy material in asphalt pavement deformation recovery, provides a processing deformation calculation formula and range, and provides a calculation formula of an electric trigger passing current value, so that a person skilled in the art can implement a test of asphalt pavement deformation research by only depending on the method, the method is suitable for wide popularization and application, has practical value, and has a promoting effect on the field.
The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the present invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present invention should be subject to the appended claims.
Claims (10)
1. A test method for service shape memory alloy recovery bituminous pavement deformation research is characterized by comprising the following steps:
alternately laying asphalt concrete and a plurality of shape memory alloy wires in a sample forming mould, arranging asphalt concrete layers adjacent to the top and the bottom of the sample forming mould, and forming and demoulding according to a conventional procedure after the sample forming mould is filled up to prepare a test sample strip with a preset size;
bending the test sample strip from two ends to the middle to a preset deformation rate in a temperature environment higher than the phase transition temperature of the shape memory alloy wire, and cooling and shaping in a temperature environment lower than zero centigrade;
and testing the deformation recovery condition of the test sample strip by using a shape memory alloy wire clamped by the test sample strip after the bending processing is electrically triggered.
2. The test method according to claim 1, wherein the test bar bending process is performed to meet one or more of the three conditions of micro-deformation, large deformation and occurrence of micro-crack deformation.
3. The test method according to claim 2, wherein the deformation ratio of the test spline micro-deformation is 1% to 2%; the deformation rate of large deformation is 2-8%; and the micro-crack deformation is the deformation rate when micro-cracks just appear in the bending process of the test sample strip.
4. The test method according to claim 3, wherein the deformation rate at the time of micro deformation, large deformation and micro crack deformation during the bending process of the test spline is calculated by the following formula:
wherein, deltaiIs the deformation rate; l0The initial length of the test specimen before bending deformation; liFor testing the length of the strip after bending deformation, said0And liThe unit of (A) is: mm.
5. The test method according to claim 1, wherein the test of the deformation recovery of the test sample strip by using the shape memory alloy wire clamped by the test sample strip after the bending processing by electric triggering specifically uses a test instrument, and the test instrument is electrically connected with the end parts of the shape memory alloy wire extending out of the two ends of the test sample strip through electric pulse test wires respectively.
6. The test method according to claim 5, wherein the energizing current of the test instrument satisfies the following formula:
c is the specific heat constant of a single shape memory alloy wire and is 535J/kg.K;
s is the area of the end face of a single shape memory alloy wire, and the diameter of the end face of the shape memory alloy wire is 1.5 multiplied by 10-4m；
Rho is the density of a single shape memory alloy wire and is 6500kg/m3；
The delta T is the difference value between the ambient temperature and the temperature for triggering the shape memory alloy wire to exert the deformation recovery action, and the unit is;
epsilon is the resistivity of a single shape memory alloy wire and is 0.8 multiplied by 10-6Ω·m；
t is the energization time in units of s.
7. The test method according to claim 1, wherein the plurality of shape memory alloy wires are distributed at intervals in the length direction of the die, and are subjected to linear cutting along the center line between two adjacent groups after being demolded to obtain a plurality of test sample bars with preset sizes.
8. The test method as claimed in claim 7, wherein the spacing distance between adjacent groups is 10-20mm, four shape memory alloy wires are distributed in any group, the total length of the test sample strip extending from both ends of each shape memory alloy wire is 40-100mm, and the ends of each group of shape memory alloy wires are flush.
9. The test method as claimed in any one of claims 1 to 8, wherein the test specimen is a rectangular parallelepiped, and has a length of 100-160mm, a width of 20-40mm and a height of 20-50mm before the bending process.
10. The test method according to claim 1, wherein the asphalt concrete is prepared by mixing and stirring an aggregate with asphalt, and the particle diameter of the aggregate is not more than 10 mm.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| RU2299417C2 (en) * | 2005-07-12 | 2007-05-20 | Сергей Константинович Илиополов | Mode of evaluation of fatigue of asphalt concrete at cyclical dynamic impacts |
| CN103115825A (en) * | 2013-01-17 | 2013-05-22 | 东南大学 | Asphalt surface course structure indoor environment simulation and high-temperature deformation test method |
| CN107421820A (en) * | 2017-08-25 | 2017-12-01 | 南京林业大学 | Asphalt mastic self-healing properties evaluation method based on shape-memory properties |
| CN107576783A (en) * | 2017-08-25 | 2018-01-12 | 南京林业大学 | A kind of asphalt mastic shape-memory properties method of testing |
| CN109440565A (en) * | 2018-12-25 | 2019-03-08 | 沈阳建筑大学 | A kind of Fe base shape memory alloy wire net bituminous pavement and preparation method thereof |
-
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- 2021-12-15 CN CN202111537829.1A patent/CN114397433A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| RU2299417C2 (en) * | 2005-07-12 | 2007-05-20 | Сергей Константинович Илиополов | Mode of evaluation of fatigue of asphalt concrete at cyclical dynamic impacts |
| CN103115825A (en) * | 2013-01-17 | 2013-05-22 | 东南大学 | Asphalt surface course structure indoor environment simulation and high-temperature deformation test method |
| CN107421820A (en) * | 2017-08-25 | 2017-12-01 | 南京林业大学 | Asphalt mastic self-healing properties evaluation method based on shape-memory properties |
| CN107576783A (en) * | 2017-08-25 | 2018-01-12 | 南京林业大学 | A kind of asphalt mastic shape-memory properties method of testing |
| CN109440565A (en) * | 2018-12-25 | 2019-03-08 | 沈阳建筑大学 | A kind of Fe base shape memory alloy wire net bituminous pavement and preparation method thereof |
Non-Patent Citations (1)
| Title |
|---|
| 牛晓东;王利;吕昊暾;龚建华;: "NiTi形状记忆合金丝的加热电流与相变时间关系的研究", 弹箭与制导学报, no. 04, 15 August 2008 (2008-08-15), pages 306 - 308 * |
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