CN102183412B - Tension-shear coupling characteristic tester of asphalt concrete material - Google Patents
Tension-shear coupling characteristic tester of asphalt concrete material Download PDFInfo
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- CN102183412B CN102183412B CN 201110040751 CN201110040751A CN102183412B CN 102183412 B CN102183412 B CN 102183412B CN 201110040751 CN201110040751 CN 201110040751 CN 201110040751 A CN201110040751 A CN 201110040751A CN 102183412 B CN102183412 B CN 102183412B
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Abstract
The invention discloses a tension-shear coupling characteristic tester of an asphalt concrete material. The tester comprises a temperature control box, vertical uploading control system for shearing a load, a transverse uploading control system for tensioning or compressing the load, and a coupling characteristic testing centre for controlling the temperature of the temperature control box, the vertical uploading and the transverse uploading and obtaining a tensioning stress and a shearing stress in the horizontal direction according to fitting of a tensioning-compressing displacement and a shearing displacement; a station platform for placing the asphalt concrete material to be tested is arranged in the temperature control box; the vertical uploading control system comprises a vertical oil cylinder, a vertical servo valve, a vertical displacement sensor and a vertical uploading controller; the transverse uploading control system comprises a transverse oil cylinder, a transverse servo valve, a horizontal displacement sensor and a transverse uploading controller; and the vertical uploading controller and the transverse uploading controller both are connected with the coupling characteristic testing centre. The tension-shear coupling characteristic tester of the asphalt concrete material can test the tension-shear coupling characteristic at controllable temperature.
Description
Technical field
The present invention relates to asphalt concrete pavement material mechanical characteristic equipment; Especially a kind of deformation characteristic and quiet dynamic response that reproduces in the on-the-spot actual use of bituminous pavement; Be that a kind of local loading that comprises stretches, local loading stretches or compression and shearing coupling, the comprehensive tester that local circulation loads; And can carry out comprehensive detection and evaluation to bituminous pavement stretching and shearing cracking destruction characteristic based on test findings and theory of mechanics and numerical simulation.
Background technology
At present, the main method of asphalt road surface surface layer deformation mechanics characteristic experimental study both at home and abroad has: marshall's method, triaxial (test) method, creep testing, wheel tracking test method and shear test method etc.The index that many countries such as the U.S., Japan and China estimate high-temperature stability is the degree of stability and the flow valuve of marshall's method, and the dynamic stability of wheel tracking test.
Marshall Test is pure empirical method; Bruce Marshell by Mississippi state highway department invented in nineteen forty-six the earliest; And formally in 1949 require test specimen under 60 ℃ of conditions, to make an experiment, and effective simulated roadway pressurized shear failure process for the AUS employing.Wheel tracking test adopts the to-and-fro movement of rubber tire to simulate the effect of traffic load, has certain emulation property, so in road engineering, obtained using widely.But because wheel tracking test rolling forming method; It is relatively poor that each organizes the repdocutbility of test specimen; Rubber tire back and forth rolls on the out-of-flatness test specimen in addition, will cause very big error when carrying out the vertical deformation test, so the discrete type of wheel tracking test is bigger; And the dynamic stability index is an indirect index, and does not have strict corresponding relationship between the wheel tracking test total deformation.
University of Nottingham has designed and developed dynamic shearing case (The Dynamic Shear Box) and Italian Ma Erkai university has designed ASTRA (Ancona Shear Testing Research and Analysis; Peace Kona shear test research and analysis) instrument is used by Carr [2001] and Ferrotti [2007] respectively.The dynamic shearing case adopts the double-deck slab that is of a size of 320mm * 200mm, applies the normal direction load and repeats shear load.That the ASTRA instrument can be tested is prismatic, and (design size is 100mm * 100mm) or the double-deck test specimen of cylinder (diameter is 94-100mm).In the test, ASTRA test applies the constant displacement rate of 2.5mm/min and perpendicular to the constant vertical load of interface plane.But this testing equipment can only be simulated the coupling analysis that vertically is pressed into load and horizontal shear load, can not solve stretching and the analysis of shearing coupled characteristic that common Pavement Low temperature load and traffic load cause.Crispino etc. [1997] have designed the dynamic shear modulus that a dynamic shear test is confirmed the pitch interface layer.They make an experiment under different frequency and temperature.Mohammad etc. [2002] have studied about the bonding between many tack coats brea bed and have confirmed best coating rate.They make an experiment through in Superpave shearing test apparatus (SST), placing a simple shear.This shear mainly be in order to ensure fracture occur in a diameter be the 150mm cylindrical specimen at the interface.Test specimen receives the constant shearing LOADING RATES of 222.5N/min, up to fracture.Write down corresponding shear load and shear displacemant, so that obtain the shear stress-displacement curve and the shear resistance at interface.Romanoschi adopts different normal direction loads with Metcalf [2002], and (138～522kPa) have carried out indoor direct shear test.They use shearing test device and take from the pitch nuclear core of full-scale test spot diameter as 95mm.Shear load applies with the transport ratio of constant 12mm//min, reaches 12mm up to total shear displacemant.Record and control shearing force F
v, normal force F
hAnd shear displacemant.
Owing to there is the direct shear test of normal direction load to have the test complicacy, design has been simplified by many countries, developed different can't be to the direct shear test equipment of load.Leutner [1979] has designed one and has been called the Leutner shear test.The brill core test specimen that diameter is 150 ± 2mm is adopted in this experiment.Can't only on the test specimen interface, apply the shear displacemant rate to load in the test; The result can't effectively simulate the interface stress form under the traffic loading.For guaranteeing the test specimen fixation and between test specimen and load equipment, suitable contact being arranged, specify test specimen interface lower thickness and upper thickness to be respectively 70mm and 25mm at least.(148～152mm) load equipment (being upper and lower shearing ring) has removable scope, so that parcel test specimen diameter for experimental facilities anchor clamps and different-diameter.Test is carried out under 20 ± 1 ℃ of code test temperature, and applies 50 ± 3mm/min standard transport ratio.Extensive accepted standard Marshall in actual road test chamber or California bearing ratio loading equipemtn also can carry out the test of 50 ± 3mm/min standard transport ratio.
Summary of the invention
Can't detect the deficiency that stretches and shear coupled characteristic for what overcome existing asphalt concrete pavement material mechanical characteristic equipment, the present invention provides a kind of and under the Controllable Temperature condition, realizes stretching and shear asphalt concrete material that coupled characteristic detects and draw and cut the coupling characteristic test appearance.
The technical solution adopted for the present invention to solve the technical problems is:
A kind of asphalt concrete material draws cuts the coupling characteristic test appearance; Comprise temperature control box, be used to accomplish shear load vertical Loading Control System, be used to accomplish stretch or the horizontal Loading Control System of compression load and in order to control temperature control box temperature, vertically load and laterally load and obtain the coupling characteristic test center of level to tension and shear stress according to tension and compression displacement and shear displacemant match; Be provided with in the said temperature control box in order to place the station platform of asphalt concrete material to be detected; Said vertical Loading Control System comprises vertical oil cylinder, vertical servo-valve, vertical displacement sensor and vertical loading control; The motion end of said vertical oil cylinder is connected with said asphalt concrete material to be detected; The controlled end of said vertical oil cylinder is connected with said vertical loading control; Said vertical oil cylinder is provided with the vertical displacement sensor, and said vertical servo-valve all is connected with said vertical loading control with the vertical displacement sensor; Said horizontal Loading Control System comprises horizontal oil cylinder, horizontal servo-valve, horizontal displacement sensors and horizontal loading control; The motion end of said horizontal oil cylinder is connected with said asphalt concrete material to be detected; The controlled end of said horizontal oil cylinder is connected with said horizontal loading control; Said horizontal oil cylinder is provided with horizontal displacement sensors; Said horizontal servo-valve all is connected with said horizontal loading control with horizontal displacement sensors, and said vertical loading control all is connected with said coupling characteristic test center with horizontal loading control.
As preferred a kind of scheme: the station platform of above-mentioned said asphalt concrete material to be detected is up and down and is symmetrical set, and the upper and lower end face of said station platform is provided with two vertical Loading Control System respectively; The side up and down of said station platform is provided with two horizontal Loading Control System respectively.
Technical conceive of the present invention is: do not have level both at home and abroad to applying tensile load and drawing the testing equipment of cutting coupling analysis in the bituminous pavement that the vertical shearing load acts on simultaneously.And conventional bituminous pavement failure mode mainly contains cracking and rut; Wherein the main reason of bituminous pavement cracking is exactly the temperature stress that vehicular load and low temperature cause; And pavement structure is under the effect of these two kinds of loads; Be a kind of stretching and shearing coupling process, domestic and international research in this respect is a blank.
The research and development temperature conditions is controlled; Can simulate asphalt concrete material stretch with the testing equipment of shearing coupling come the simulated roadway structure in actual use the testing equipment of the mechanical response under traffic load and temperature load effect have great importance; Also can be used for theoretical research and engineering site simultaneously and detect, for actual Engineering Quality Control and asphalt concrete material performance study provide foundation and support.
Beneficial effect of the present invention mainly shows: under the Controllable Temperature condition, realize stretching (or compression) and the detection of shearing coupled characteristic.
Description of drawings
Fig. 1 cuts the coupling test system synoptic diagram for asphalt draws;
Fig. 2 is closed-loop servosystem control principle figure;
Fig. 3 is the I-I diagrammatic cross-section of Fig. 1.
Embodiment
Below in conjunction with accompanying drawing the present invention is further described.
With reference to Fig. 1～Fig. 3; A kind of asphalt concrete material draws cuts the coupling characteristic test appearance; Comprise temperature control box 10, be used to accomplish shear load vertical Loading Control System, be used to accomplish stretch or the horizontal Loading Control System of compression load and in order to control temperature control box temperature, vertically load and laterally load and obtain the coupling characteristic test center 1 of level to tension and shear stress according to tension and compression displacement and shear displacemant match; Be provided with in the said temperature control box 10 in order to place the station platform of asphalt concrete material to be detected; Said vertical Loading Control System comprises vertical oil cylinder 4, vertical servo-valve 6, vertical displacement sensor 8 and vertical loading control 2; The motion end of said vertical oil cylinder 4 is connected with said asphalt concrete material to be detected; The controlled end of said vertical oil cylinder 4 is connected with said vertical loading control 2, and said vertical oil cylinder 4 is provided with vertical displacement sensor 8, and said vertical servo-valve 6 all is connected with said vertical loading control 2 with vertical displacement sensor 8; Said horizontal Loading Control System comprises horizontal oil cylinder 5, laterally servo-valve 7, horizontal displacement sensors 9 and horizontal loading control 3; The motion end of said horizontal oil cylinder 5 is connected with said asphalt concrete material test specimen loading bin to be detected; The controlled end of said horizontal oil cylinder 5 is connected with said horizontal loading control 3; Said horizontal oil cylinder 5 is provided with horizontal displacement sensors 9; Said horizontal servo-valve 7 all is connected with said horizontal loading control 3 with horizontal displacement sensors 9, and said vertical loading control 2 all is connected with said coupling characteristic test center with horizontal loading control 3.
The station platform of above-mentioned said asphalt concrete material to be detected is up and down and is symmetrical set, and the upper and lower end face of said station platform is provided with two vertical Loading Control System respectively and is used to accomplish shear action; The side up and down of said station platform is provided with two horizontal Loading Control System respectively.
Shown in Figure 1 for asphalt concrete pavement material draws the composition synoptic diagram of cutting the coupled characteristic comprehensive tester, this equipment by support, coupling characteristic test center 1, vertical loading control 2, laterally loading control 3, vertical oil cylinder 4, laterally oil cylinder 5, vertical servo-valve 6, laterally servo-valve 7, vertical displacement sensor 8, horizontal displacement sensors 9, temperature control box 10 are formed.
Test specimen places on the station platform of temperature control box 10, and vertical oil cylinder 4 links to each other with vertical loading control 2, and laterally oil cylinder 5 links to each other with horizontal loading control 3, and vertical loading control links to each other with coupling characteristic test center 1 with horizontal loading control.
The closed-loop servosystem control principle is as shown in Figure 2.
The asphalt of present embodiment draws (pressure) to cut coupling test system, can realize following function through adjusting and the control to vertical Loading Control System, horizontal Loading Control System and temperature control box 10:
A item content of the test: the research asphalt (is realized by horizontal loading system) under the effect of fixing pressure load; Different shear loads (being realized by vertical loading system) are to the effect of asphalt, thus the anti-shear performance under the press loading effect of judgement asphalt.
B item content of the test: can realize drawing effect through horizontal Loading Control System to the bituminous concrete test specimen; And on this basis; Realize test specimen is applied the shear load effect through vertical Loading Control System, judge that asphalt draws the anti-shear performance under the load action thereby reach.
C item content of the test:, can test anti-shear performance and alternating temperature and the driving equivalent load coupling of asphalt in-30 ℃～60 ℃ scopes through the temperature control system of temperature control box 10.
Bituminous concrete shear stress and tension: can obtain asphalt concrete material at level different tension and compression displacement ε constantly under the effect that loads and vertically load through test
xWith shear displacemant ε
y, can further obtain level to tensile stress sigma through match
xWith value of shearing σ
yThereby, can study the coupling relation between the shear stress that asphalt tension that cause the cryogenic temperature field and traffic load cause.
Advantages such as present embodiment has used the self-regulating PID of parameter (P is differential as ratio, I as integration, D) control technology, it the has absorbed elimination stable state of rapid reaction function, I control of P control action is poor, the forecast function of D control but must the appropriate design parameter.Based on computer and I/O parts, adopt graphical tools that system is monitored, carry out multi-channel data acquisition, storage, data processing and curve display simultaneously.Linear feed forward prediction adopts PID control, and system then adopts displacement type PID control, and constant with shear rate is standard; The high-precision hydraulic synchro control of vertical load equally also adopts displacement type PID to control and realizes.Shearing test device is through the operation of accepting feedback signal value and the making load one side command value that can follow up, thereby realizes high-speed real-time collection and complicated control.Through adopting a closed circulation that is positioned at control system software to realize constant normal stiffness boundary condition, cooperate electron servo control simultaneously.Control and the nonlinear feedback analysis of measuring realize on the PC window, through a multi-functional analog digital, digital simulation, digital input and output control panel (A/D, D/A and DIO).The test figure of collecting comprises normal stress, shear stress, corresponding displacement and loads the value that right cylinder valve level loads and vertically loads.
Claims (1)
1. an asphalt concrete material draws and cuts the coupling characteristic test appearance; It is characterized in that: said tester comprises temperature control box, be used to accomplish the vertical Loading Control System of shear load, be used to accomplish stretch or the horizontal Loading Control System of compression load and in order to control temperature control box temperature, vertically load and laterally load and obtain the coupling characteristic test center of level to tension and shear stress according to tension and compression displacement and shear displacemant match; Be provided with in the said temperature control box in order to place the station platform of asphalt concrete material to be detected; Said vertical Loading Control System comprises vertical oil cylinder, vertical servo-valve, vertical displacement sensor and vertical loading control; The motion end of said vertical oil cylinder is connected with said asphalt concrete material to be detected; The controlled end of said vertical oil cylinder is connected with said vertical loading control; Said vertical oil cylinder is provided with the vertical displacement sensor, and said vertical servo-valve all is connected with said vertical loading control with the vertical displacement sensor; Said horizontal Loading Control System comprises horizontal oil cylinder, horizontal servo-valve, horizontal displacement sensors and horizontal loading control; The motion end of said horizontal oil cylinder is connected with said asphalt concrete material to be detected; The controlled end of said horizontal oil cylinder is connected with said horizontal loading control; Said horizontal oil cylinder is provided with horizontal displacement sensors; Said horizontal servo-valve all is connected with said horizontal loading control with horizontal displacement sensors, and said vertical loading control all is connected with said coupling characteristic test center with horizontal loading control; The station platform of said asphalt concrete material to be detected is up and down and is symmetrical set, and the upper and lower end face of said station platform is provided with two vertical Loading Control System respectively and accomplishes the shear load effect; The side up and down of said station platform is provided with two horizontal Loading Control System respectively and accomplishes stretching or compression load effect.
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| CN 201110040751 CN102183412B (en) | 2011-02-18 | 2011-02-18 | Tension-shear coupling characteristic tester of asphalt concrete material |
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| CN 201110040751 CN102183412B (en) | 2011-02-18 | 2011-02-18 | Tension-shear coupling characteristic tester of asphalt concrete material |
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| CN102183412B true CN102183412B (en) | 2012-12-12 |
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| CN102507342A (en) * | 2011-11-24 | 2012-06-20 | 长安大学 | Testing method and device for researching on shear property of asphalt mixture |
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| CN107024389B (en) * | 2017-05-25 | 2023-11-24 | 扬州大学 | Asphalt mixture transverse shear deformation acquisition device and method thereof |
| CN107843485B (en) * | 2017-12-19 | 2023-06-23 | 浙江工业大学 | Temperature control shearing box device for direct shearing experiment and operation method |
| CN110658079B (en) * | 2019-09-18 | 2024-04-05 | 浙江大学 | Indoor characterization method of asphalt surface layer under multiple environment gradient coupling |
| CN110763566B (en) * | 2019-11-28 | 2021-05-11 | 大连理工大学 | Method for determining circumferential thickness anisotropy coefficient of anisotropic pipe |
| CN113447370B (en) * | 2021-06-24 | 2023-05-30 | 江苏省建筑工程质量检测中心有限公司 | Integral tensile and shear test system and method for precast concrete sandwich heat-insulating wallboard |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5817946A (en) * | 1996-10-28 | 1998-10-06 | Test Quip, Inc. | Gyratory compaction apparatus for creating compression and shear forces in a sample material |
| CN101408489A (en) * | 2008-11-21 | 2009-04-15 | 哈尔滨工业大学 | Concrete plane complicated applied force test device |
| CN101464249A (en) * | 2009-01-09 | 2009-06-24 | 长安大学 | Interlayer tensile strength detecting instrument for asphalt pavement |
| CN101464239A (en) * | 2009-01-09 | 2009-06-24 | 长安大学 | Interlayer shear strength detecting instrument for asphalt pavement |
| CN201583450U (en) * | 2009-12-09 | 2010-09-15 | 胡小弟 | Asphalt mixture cracking resistance tester |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2008026020A (en) * | 2006-07-18 | 2008-02-07 | Maeda Corp | Compression strength test control method of concrete |
-
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Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5817946A (en) * | 1996-10-28 | 1998-10-06 | Test Quip, Inc. | Gyratory compaction apparatus for creating compression and shear forces in a sample material |
| CN101408489A (en) * | 2008-11-21 | 2009-04-15 | 哈尔滨工业大学 | Concrete plane complicated applied force test device |
| CN101464249A (en) * | 2009-01-09 | 2009-06-24 | 长安大学 | Interlayer tensile strength detecting instrument for asphalt pavement |
| CN101464239A (en) * | 2009-01-09 | 2009-06-24 | 长安大学 | Interlayer shear strength detecting instrument for asphalt pavement |
| CN201583450U (en) * | 2009-12-09 | 2010-09-15 | 胡小弟 | Asphalt mixture cracking resistance tester |
Non-Patent Citations (1)
| Title |
|---|
| JP特开2008-26020A 2008.02.07 |
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