CN2789755Y - Tester adapted to testing soil body fracture parameter - Google Patents
Tester adapted to testing soil body fracture parameter Download PDFInfo
- Publication number
- CN2789755Y CN2789755Y CN 200520071672 CN200520071672U CN2789755Y CN 2789755 Y CN2789755 Y CN 2789755Y CN 200520071672 CN200520071672 CN 200520071672 CN 200520071672 U CN200520071672 U CN 200520071672U CN 2789755 Y CN2789755 Y CN 2789755Y
- Authority
- CN
- China
- Prior art keywords
- loading
- sample
- load
- displacement
- crack
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Images
Landscapes
- Investigating Strength Of Materials By Application Of Mechanical Stress (AREA)
Abstract
The utility model relates to a tester adapted to testing the fracture parameters of a soil body, which is composed of a loading handle, a gearbox, a dowel bar, a loading sensor, a loading bar, a dial gauge, a conductometer, a universal roller bracket and a sample, wherein the loading handle is connected with the gearbox which is connected with the dowel bar, the dowel bar is connected with the loading sensor connected with the loading bar, the dial gauge is connected with the loading bar of the sample, an electrode in the dial gauge is directly inserted into both ends of the sample and the universal roller bracket is placed on the bottom part of the sample. The utility model has the advantages of high measurement precision, simple and convenient operation and easily guaranteed sample quality. The influence of the self weight of the sample to the test process and the test result is eliminated, the loading-displacement curve of the whole loading process can be measured, the influences of the crack incision quality of the sample and the mounting quality of an extensometer on the test result can be effectively avoided, the critical load of the crack initiation of a crack is determined by the method of a loading displacement curve and a conductance displacement curve and the accuracy of the critical load is guaranteed.
Description
Technical field
The utility model relates to a kind of tester that is suitable for testing soil mass fragmentation parameters, belong to soil mass fragmentation parameters testing tool technical field.
Background technology
What use always in the prior art is standard three-point bending fracture test method.Described standard three point bending test is the standard method of test metal and fracture parameters of concrete, and the deadweight direction of loading direction and sample is consistent in the test.During the fragmentation parameters of the relatively poor material of break resistance such as the test soil body etc., the rupture failure that causes because of the sample deadweight may take place in sample before loading, even this destruction is not taken place, also conducting oneself with dignity to compare can not ignore with breaking load because of sample obviously influences test findings; Measure crack mouth opening displacement with the displacement tens(i)ometer in the test, this makes the installation quality of sample crack kerf quality and tens(i)ometer have considerable influence to test findings, and for soil sample, the displacement tens(i)ometer is difficult to install especially; Moreover, be difficult to obtain the trial curve behind the load peak value during with existing method test soil sample; For the situation of no obvious load peak value in the load-displacement curve, determine that with existing method the precision of the critical load of crack crack initiation is difficult to guarantee.
Summary of the invention
The purpose of this utility model is to overcome the defective of above-mentioned conventional tearing test method and testing tool, proposes a kind of instrument and method of testing that is applicable to research soil mass fragmentation characteristic, has not only easy and simple to handle but also can guarantee the soil mass fragmentation instrument of precision.It has not only eliminated the influence of sample deadweight to process of the test and test findings, and has improved measuring accuracy, the fracture characteristics experimental study of the suitable relatively poor material of this class break resistance of the soil body.Technical solution of the present utility model: soil mass fragmentation parameters tester, its structure is that the loading handle connects wheel box, wheel box connects transmission rod, transmission rod connects load sensor, load sensor connects loading pole, dial gauge links to each other with the sample loading pole, and the electrode in the conductivity meter directly inserts the sample two ends, and universal rolling wheel supports and is positioned over the sample bottom.
The method of testing of soil mass fragmentation parameters is that the loading mode is simple loading or cyclic loading, the loading direction is a horizontal direction, load is by a journey high-precision load sensor measurement in a small amount, the loading pole displacement is measured by dial gauge, the sample electricity is led by conductivity meter and is measured, and critical load is determined by load-displacement curve and conductance increment displacement curve method.
Advantage of the present utility model: the measuring accuracy height, easy and simple to handle, less demanding to sample crack kerf quality, sample mass is easy to guarantee.The loading direction is vertical with sample deadweight direction, has eliminated the influence of sample deadweight to process of the test and test findings; Can measure the load-displacement curve of whole loading process, comprise softening section; The high-precision load sensor of little range can record the payload values of enough accuracy; Dial gauge is measured the loading pole displacement, avoids the influence to test findings of sample crack kerf quality and tens(i)ometer installation quality; The electricity of sample is led variation in the conductivity meter experiment with measuring; Determine the critical load of crack crack initiation by load-displacement curve and two kinds of methods of conductance increment displacement curve, guaranteed the accuracy of critical load.
Description of drawings
Accompanying drawing 1 is a structural representation of the present utility model.
Accompanying drawing 2 is the utility model structural principle synoptic diagram.
The test result figure of the load-displacement curve when accompanying drawing 3 is simple loadings.
The test result figure of the conductance increment displacement curve when accompanying drawing 4 is simple loadings.
The test result figure of the load-displacement curve when accompanying drawing 5 is cyclic loading.
The test result figure of the conductance increment displacement curve when accompanying drawing 6 is cyclic loading.
Accompanying drawing 7 is circuit structure calcspars of conductivity meter in the structure of the present invention.
Among the figure 1 ' is that loading handle, 2 ' is that wheel box, 3 ' is that transmission rod, 4 ' is that load sensor, 5 ' is that loading pole, 6 ' is that dial gauge, 7 ' is that conductivity meter, 8 ' is that universal rolling wheel support, 9 ' is that sample, AA, BB are that sample fulcrum, CC are that sample loading pole, DD are that electrode, F are that crack otch, W are that specimen width, B are that sample thickness, P are that load, a are that the penetration of fracture, S are that sample effective length, 10 ' is an electrode; 11 ' is that sensor 12 ' is an amplifier; 13 ' is the A/D conversion; 14 ' is data acquisition; 15 ' is central processing unit; 16 ' is the data outputs.
Embodiment
Above-mentioned two kinds of curves all can be used for determining the size of critical load.For curve shown in the accompanying drawing 3,4, before the load peaking, the sample electricity is not led and is changed, be that the crack is not expanded, behind the load peaking, electricity is led with displacement and is changed, be that the crack is expanded, the load peak value is exactly the critical load of crack crack initiation, and the displacement of critical load correspondence just in time is the displacement of the flex point correspondence of conductance increment displacement curve, two kinds of unanimities as a result that method is determined.Tangible load peak value does not appear in the load-displacement curve of some situation, and critical load can determine that the accuracy of critical load can guarantee according to the flex point of conductance increment displacement curve.
Sample effective length S=18.5cm, specimen width W are respectively 4.4,4.6,4.8cm, and sample thickness B is respectively 2.20,2.30,2.40cm, and penetration of fracture a is respectively 2.00,2.25,2.50cm.
The loading direction be level to, load by one in a small amount the journey high-precision load sensor measure, the loading pole displacement is measured by dial gauge, the sample electricity is led by conductivity meter and is measured, critical load is represented by load-displacement curve or conductance increment displacement curve.Described conductivity meter is formed by prior art electrode 10 ', sensor 11 ', amplifier 12 ', A/D conversion 13 ', data acquisition 14 ', central processing unit 15 ', data output 16 ' serial connection.
For simple loading situation, load, loading pole displacement, sample conductance measurement value are shown in subordinate list 1 in the test, and conductance increment is obtained by diagometer in the table.Critical load can be obtained by load-displacement curve or conductance increment displacement curve.Draw load-displacement curve according to load P and loading pole displacement, as shown in Figure 3.Transverse axis is the loading pole displacement in the accompanying drawing 3, and the longitudinal axis is a load.As can be seen, when load during less than peak value, load is linear substantially with the loading pole displacement and increases in the accompanying drawing 3, and the load peak value is exactly a critical load.Lead variable quantity and loading pole displacement drafting conductance increment displacement curve according to the electricity of sample, as shown in Figure 4.Transverse axis is the loading pole displacement in the accompanying drawing 4, and the longitudinal axis is a conductance increment.
Comparative drawings figs 4 and accompanying drawing 3 as can be known, during less than the displacement of load peak value correspondence, the sample conductance increment is zero in the loading pole displacement, promptly the crack is not expanded; When loading pole displacement during greater than the displacement of load peak value correspondence, the sample electricity is led and is changed, and promptly the crack is expanded; The loading pole displacement of load peak value correspondence just in time is the displacement of the flex point correspondence of conductance increment displacement curve, i.e. the displacement of crack crack initiation, and the load peak value is exactly a critical load.Two kinds of unanimities as a result that method is determined.
For the cyclic loading situation, load, loading pole displacement, sample conductance measurement value are shown in subordinate list 2 in the test, and conductance increment is obtained by diagometer in the table.Critical load can be obtained by load-displacement curve or conductance increment displacement curve.Draw load-displacement curve according to load P and loading pole displacement, as shown in Figure 5, transverse axis is the loading pole displacement in the accompanying drawing 5, and the longitudinal axis is a load.Lead variable quantity and loading pole displacement drafting conductance increment displacement curve according to the electricity of sample, as shown in Figure 6, transverse axis is the loading pole displacement in the accompanying drawing 6, and the longitudinal axis is a conductance increment.All can determine critical load according to accompanying drawing 5,6, its method is identical with simple loading situation, repeats no more here.
It can also be seen that from accompanying drawing 5,6 in the off-load before the load peaking-loading circulation, electricity is not led and changed, show that the crack do not expand; In off-load behind the load peaking-loading circulation, electricity is led and is remained unchanged during off-load, and electricity is led slow variation during loading, reach the peak value of loading again when load after, electricity is led along virgin curve and is changed, the crack is not expanded when showing off-load, the crack is expanded during loading.
Probationary certificate has been eliminated the influence of soil sample deadweight to process of the test and test findings.Traditional standard three-point bending fracture test method is improved, loading direction by vertically to change into level to, thereby make loading direction and soil sample deadweight direction vertical.The high-precision load sensor of little range has guaranteed the load measurement precision.The sample bottom is used universal rolling wheel and is supported, and does not retrain the distortion of sample when eliminating test bottom friction power.Dial gauge is used to measure the displacement of sample loading pole.Measure the electricity of sample leads with conductivity meter.Lead the critical load that the displacement curve method is determined the sample crack initiation with load-displacement curve method and electricity, can guarantee the accuracy of critical load.Can record the load-loading pole displacement curve in the whole fracture process of sample.Can carry out three-point bending fracture test and 4 asymmetric tearing tests respectively.Can test fracture toughness KIC, the KIIC of soil sample I type and II type crack problem and the K factor of the compound crack problem of I-II respectively.
The simple bearing test test data of table 1
| Displacement/mm | Load/N | Electricity is led/S | Conductance increment/S | Displacement/mm | Load/N | Electricity is led/S | Conductance increment/ |
| 0 | 0 | 25.2 | 0 | 0.8 | 4.8 | 23 | -2.2 |
| 0.05 | 1.3 | 25.2 | 0 | 0.85 | 4 | 22.7 | -2.5 |
| 0.1 | 2.8 | 25.2 | 0 | 0.9 | 3.7 | 22.4 | -2.8 |
| 0.15 | 4.5 | 25.2 | 0 | 0.95 | 3.4 | 22.1 | -3.1 |
| 0.2 | 5.8 | 25.2 | 0 | 1 | 3.3 | 21.8 | -3.4 |
| 0.25 | 8 | 25.2 | 0 | 1.05 | 3 | 21.5 | -3.7 |
| 0.3 | 10.6 | 25.2 | 0 | 1.1 | 2.9 | 21.2 | -4 |
| 0.35 | 13 | 25.2 | 0 | 1.15 | 2.8 | 21 | -4.2 |
| 0.4 | 14.1 | 25.2 | 0 | 1.2 | 2.7 | 20.7 | -4.5 |
| 0.45 | 11.6 | 24.9 | -0.3 | 1.25 | 2.6 | 20.5 | -4.7 |
| 0.5 | 9.5 | 24.6 | -0.6 | 1.3 | 2.4 | 20.2 | -5 |
| 0.55 | 7.6 | 24.4 | -0.8 | 1.35 | 2.2 | 19.9 | -5.3 |
| 0.6 | 6.5 | 24.1 | -1.1 | 1.4 | 2.1 | 19.7 | -5.5 |
| 0.65 | 5.8 | 23.8 | -1.4 | 1.45 | 1.9 | 19.5 | -5.7 |
| 0.7 | 5.5 | 23.6 | -1.6 | 1.5 | 1.7 | 19.3 | -5.9 |
| 0.75 | 5.2 | 23.3 | -1.9 | 1.55 | 1.5 | 19.1 | -6.1 |
Table 2 cyclic loading experimental test data
| Displacement/mm | Load/N | Electricity is led/S | Conductance increment/S | Displacement/mm | Load/N | Electricity is led/S | Conductance increment/ |
| 0 | 0 | 31.9 | 0 | 0.65 | 7.4 | 30.9 | -1 |
| 0.025 | 0.4 | 31.9 | 0 | 0.675 | 7 | 30.8 | -1.1 |
| 0.05 | 0.8 | 31.9 | 0 | 0.7 | 6.1 | 30.7 | -1.2 |
| 0.075 | 1.3 | 31.9 | 0 | 0.675 | 3.5 | 30.7 | -1.2 |
| 0.1 | 2 | 31.9 | 0 | 0.65 | 2.6 | 30.7 | -1.2 |
| 0.125 | 2.5 | 31.9 | 0 | 0.625 | 1.5 | 30.7 | -1.2 |
| 0.15 | 3 | 31.9 | 0 | 0.6 | 0.8 | 30.7 | -1.2 |
| 0.175 | 3.5 | 31.9 | 0 | 0.575 | 0 | 30.7 | -1.2 |
| 0.2 | 4.1 | 31.9 | 0 | 0.6 | 3.5 | 30.65 | -1.25 |
| 0.225 | 4.9 | 31.9 | 0 | 0.625 | 4.3 | 30.6 | -1.3 |
| 0.25 | 5.5 | 31.9 | 0 | 0.65 | 5 | 30.55 | -1.35 |
| 0.275 | 6.1 | 31.9 | 0 | 0.675 | 5.2 | 30.5 | -1.4 |
| 0.3 | 6.9 | 31.9 | 0 | 0.7 | 5.4 | 30.4 | -1.5 |
| 0.325 | 7.7 | 31.9 | 0 | 0.725 | 5.2 | 30.3 | -1.6 |
| 0.35 | 8.1 | 31.9 | 0 | 0.75 | 5 | 30.2 | -1.7 |
| 0.375 | 8.8 | 31.9 | 0 | 0.775 | 4.6 | 30.1 | -1.8 |
| 0.4 | 9.2 | 31.9 | 0 | 0.8 | 4.3 | 30 | -1.9 |
| 0.375 | 5.5 | 31.9 | 0 | 0.825 | 4.1 | 29.9 | -2 |
| 0.35 | 3.1 | 31.9 | 0 | 0.85 | 3.9 | 29.8 | -2.1 |
| 0.325 | 1.8 | 31.9 | 0 | 0.825 | 1.7 | 29.8 | -2.1 |
| 0.3 | 0.5 | 31.9 | 0 | 0.8 | 0.8 | 29.8 | -2.1 |
| 0.275 | 0 | 31.9 | 0 | 0.775 | 0 | 29.8 | -2.1 |
| 0.3 | 3.6 | 31.9 | 0 | 0.8 | 2.5 | 29.75 | -2.15 |
| 0.325 | 5.3 | 31.9 | 0 | 0.825 | 2.9 | 29.7 | -2.2 |
| 0.35 | 6.9 | 31.9 | 0 | 0.85 | 3.3 | 29.65 | -2.25 |
| 0.375 | 7.9 | 31.9 | 0 | 0.875 | 3.2 | 29.6 | -2.3 |
| 0.4 | 9.2 | 31.9 | 0 | 0.9 | 3 | 29.5 | -2.4 |
| 0.425 | 10 | 31.9 | 0 | 0.925 | 2.9 | 29.4 | -2.5 |
| 0.45 | 10.95 | 31.9 | 0 | 0.95 | 2.8 | 29.3 | -2.6 |
| 0.475 | 11.6 | 31.9 | 0 | 0.975 | 2.7 | 29.2 | -2.7 |
| 0.5 | 10.4 | 31.8 | -0.1 | 1 | 2.6 | 29.1 | -2.8 |
| 0.475 | 6.1 | 31.8 | -0.1 | 1.025 | 2.5 | 29 | -2.9 |
| 0.45 | 4.8 | 31.8 | -0.1 | 1.05 | 2.4 | 28.9 | -3 |
| 0.425 | 3.4 | 31.8 | -0.1 | 1.075 | 2.3 | 28.8 | -3.1 |
| 0.4 | 1.9 | 31.8 | -0.1 | 1.1 | 2.2 | 28.7 | -3.2 |
| 0.375 | 1.1 | 31.8 | -0.1 | 1.125 | 2.1 | 28.6 | -3.3 |
| 0.35 | 0 | 31.8 | -0.1 | 1.15 | 2 | 28.5 | -3.4 |
| 0.375 | 3.9 | 31.75 | -0.15 | 1.175 | 1.9 | 28.4 | -3.5 |
| 0.4 | 5.5 | 31.7 | -0.2 | 1.2 | 1.8 | 28.3 | -3.6 |
| 0.425 | 7.1 | 31.65 | -0.25 | 1.225 | 1.8 | 28.2 | -3.7 |
| 0.45 | 8.2 | 31.6 | -0.3 | 1.25 | 1.7 | 28.1 | -3.8 |
| 0.475 | 9.2 | 31.55 | -0.35 | 1.275 | 1.7 | 28 | -3.9 |
| 0.5 | 9.4 | 31.5 | -0.4 | 1.3 | 1.7 | 29.1 | -4 |
| 0.525 | 9.2 | 31.4 | -0.5 | 1.325 | 1.6 | 27.8 | -4.1 |
| 0.55 | 8.8 | 31.3 | -0.6 | 1.35 | 1.6 | 30.1 | -4.2 |
| 0575 | 8.6 | 31.2 | -0.7 | 1.375 | 1.6 | 27.6 | -4.3 |
| 0.6 | 8.2 | 31.1 | -0.8 | 1.4 | 1.6 | 31.1 | -4.4 |
| 0.625 | 7.8 | 31 | -0.9 |
Claims (1)
1, a kind of tester that is suitable for testing soil mass fragmentation parameters, it is characterized in that loading handle (1 ') connects wheel box (2 '), wheel box (2 ') connects transmission rod (3 '), transmission rod (3 ') connects load sensor (4 '), load sensor (4 ') connects loading pole (5 '), dial gauge (6 ') links to each other with sample loading pole (5 '), and the electrode in the conductivity meter (7 ') (DD) directly inserts sample (9 ') two ends, and universal rolling wheel support (8 ') is positioned over sample (9 ') bottom.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200520071672 CN2789755Y (en) | 2005-05-16 | 2005-05-16 | Tester adapted to testing soil body fracture parameter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200520071672 CN2789755Y (en) | 2005-05-16 | 2005-05-16 | Tester adapted to testing soil body fracture parameter |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN2789755Y true CN2789755Y (en) | 2006-06-21 |
Family
ID=36790089
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 200520071672 Expired - Fee Related CN2789755Y (en) | 2005-05-16 | 2005-05-16 | Tester adapted to testing soil body fracture parameter |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN2789755Y (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100370240C (en) * | 2005-05-16 | 2008-02-20 | 河海大学 | Method for testing soil mass fragmentation parameters and tester thereof |
| CN102128742A (en) * | 2010-12-07 | 2011-07-20 | 重庆交通大学 | Testing device and method of soil body II-type fracture damage |
| CN105865924A (en) * | 2016-06-13 | 2016-08-17 | 南京大学 | Cohesive-soil strain-control-type I-type fracture toughness tester and testing method |
| CN108896409A (en) * | 2018-06-12 | 2018-11-27 | 河海大学 | A kind of 3 points of curved pilot systems of floated level and test method of the fracture of test material I type |
| CN114577564A (en) * | 2022-02-11 | 2022-06-03 | 中国电建集团西北勘测设计研究院有限公司 | Method for loading cracks of prefabricated mortar test piece by three-point bending |
-
2005
- 2005-05-16 CN CN 200520071672 patent/CN2789755Y/en not_active Expired - Fee Related
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100370240C (en) * | 2005-05-16 | 2008-02-20 | 河海大学 | Method for testing soil mass fragmentation parameters and tester thereof |
| CN102128742A (en) * | 2010-12-07 | 2011-07-20 | 重庆交通大学 | Testing device and method of soil body II-type fracture damage |
| CN105865924A (en) * | 2016-06-13 | 2016-08-17 | 南京大学 | Cohesive-soil strain-control-type I-type fracture toughness tester and testing method |
| CN108896409A (en) * | 2018-06-12 | 2018-11-27 | 河海大学 | A kind of 3 points of curved pilot systems of floated level and test method of the fracture of test material I type |
| CN114577564A (en) * | 2022-02-11 | 2022-06-03 | 中国电建集团西北勘测设计研究院有限公司 | Method for loading cracks of prefabricated mortar test piece by three-point bending |
| CN114577564B (en) * | 2022-02-11 | 2023-02-10 | 中国电建集团西北勘测设计研究院有限公司 | Method for prefabricating cracks of mortar test piece by three-point bending loading |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN2789755Y (en) | Tester adapted to testing soil body fracture parameter | |
| CN101694436B (en) | Strain control method of cantilever bending and loading low-circle fatigue test | |
| CN104949883A (en) | Device for testing fracture toughness of sheet center crack tensile sample | |
| CN105300796B (en) | A kind of sheet metal Instability wrinkling test and evaluation device of adjustable Normal Constraint | |
| Lim et al. | Design and development of a miniaturised tensile testing machine | |
| CN100370240C (en) | Method for testing soil mass fragmentation parameters and tester thereof | |
| DE102010052814B4 (en) | Device and method for avoiding instabilities of loaded structures | |
| CN105806210A (en) | High-resolution strain testing method | |
| KR20120074353A (en) | Three point bending test machine | |
| CN201166629Y (en) | High precision great range torsional angle measuring instrument | |
| CN211317204U (en) | Displacement measuring equipment | |
| CN102384878B (en) | Scale-span in situ micro-nano stretching/compressing hydraulic drive testing device under microscopic assembly | |
| CN105698996A (en) | Shearing strength testing device for pile-soil interface | |
| CN106403868A (en) | Crack width change dynamic monitoring method based on strain induction | |
| CN114636626A (en) | Method for measuring trabecula beam bottom tensile strain based on four-point bending fatigue test | |
| CN106248027A (en) | Fracture width variation monitoring method based on string vibration frequency | |
| CN211876970U (en) | Ball screw clearance measuring device | |
| CN207366350U (en) | A kind of detection test specimen of Creep of Concrete-filled Steel Tube | |
| CN1587892A (en) | Plane strain measurement sensor | |
| CN206291842U (en) | A kind of impact specimen lateral expansion test fixture | |
| CN210374978U (en) | A quick measuring device for bridge load | |
| CN211121764U (en) | Calibration force application device for power indicator force sensor of shock absorber | |
| CN109187184B (en) | Soil pressure test demonstration system and method | |
| CN202501977U (en) | Experimental device for testing normal-stiffness and retardant features of double-bolt joint surface | |
| CN202351139U (en) | Cross-scale in situ micro-nano tensile/ compression hydraulic driving test device under microscopic components |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C19 | Lapse of patent right due to non-payment of the annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |