CN107907438B - Device and method for detecting and evaluating abrasion and polishing performance of coarse aggregate - Google Patents
Device and method for detecting and evaluating abrasion and polishing performance of coarse aggregate Download PDFInfo
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- CN107907438B CN107907438B CN201711246469.3A CN201711246469A CN107907438B CN 107907438 B CN107907438 B CN 107907438B CN 201711246469 A CN201711246469 A CN 201711246469A CN 107907438 B CN107907438 B CN 107907438B
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N3/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N3/56—Investigating resistance to wear or abrasion
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N1/00—Sampling; Preparing specimens for investigation
- G01N1/28—Preparing specimens for investigation including physical details of (bio-)chemical methods covered elsewhere, e.g. G01N33/50, C12Q
- G01N1/286—Preparing specimens for investigation including physical details of (bio-)chemical methods covered elsewhere, e.g. G01N33/50, C12Q involving mechanical work, e.g. chopping, disintegrating, compacting, homogenising
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
- G01N33/42—Road-making materials
Abstract
The invention discloses a device and a method for detecting and evaluating abrasion and polishing performance of coarse aggregates, wherein the device comprises a base, a central processing unit, a servo motor and an abrasion and polishing performance detection component; the device also comprises an upright post, a force value sensor and a sample pressure regulating mechanism; the servo motor is fixedly arranged on the base and is controlled by the central processing unit; the abrasion and polishing performance detection assembly comprises a coarse grinding wheel, a fine grinding wheel and a pure rubber wheel; the upright post is used for fixing a force value sensor, and the force value sensor is positioned between the upright post and the sample pressure regulating mechanism; the sample pressure adjusting mechanism comprises weights, weight trays, ball linear slide rails and matched sliding connecting columns; the lower end of the sliding connecting column is provided with a sample fixing groove. The invention uses the coarse grinding wheel and the fine grinding wheel to carry out abrasion test on the sample, uses the pure rubber wheel to carry out polishing test on the coarse aggregate, and has accurate test process, time saving and labor saving.
Description
Technical Field
The invention relates to the technical field of highway pavement coarse aggregate abrasion and polishing performance, in particular to equipment and a method for detecting and evaluating the coarse aggregate abrasion and polishing performance.
Background
Currently, the grinding performance is an index reflecting the capability of stone to resist the grinding action of tires, and the aggregate grinding performance is a key index for determining whether a certain aggregate can be used for an asphalt pavement anti-skid wearing layer. The stone with high polishing value is used for paving the road surface layer of the road, so that the anti-skid capability of the road surface can be improved, and the safe running of the vehicle can be ensured. The wear value is a value that determines the ability of the stone to resist surface wear and is suitable for use in resisting wheel wear to aggregate used in the road surface anti-skid surface layer.
After the surface layer of the asphalt pavement is subjected to long-term vehicle load, the asphalt film wrapped on the surface of the aggregate is gradually worn away, the aggregate is gradually exposed, and the pavement mainly depends on the anti-skid force provided by the aggregate. Thus, under the action of the tire, not only is the aggregate required to have high abrasion resistance, but also high abrasion resistance is required. However, the polishing value test method adopted in China at present has a certain human factor from the material to the test method, so that the uncertainty of an important index of the polishing value of the anti-slip surface coarse aggregate of the asphalt pavement is caused, and the asphalt pavement becomes a soft rib in the construction of the expressway asphalt pavement in China.
The abrasion loss of coarse aggregate is an important index of aggregate service performance, especially asphalt mixture and base aggregate, is closely related to rut resistance, wear resistance and durability of asphalt pavement, and is generally small in abrasion loss, aggregate silhouette, wear resistance and good in durability. The stone with high content of weak particles and serious weathering is subjected to abrasion test, so that the stone is seriously crushed, and the index is difficult to pass. Abrasion testing is also an important tool for stone preference.
The existing standard JTG E42-2005 'road engineering aggregate test procedure' has the defects that the test procedure is complex and complicated, the test period is long, the error factor caused by the test process is more, the deviation of the measured data of the polishing value is often too large, the method is a detection item which is difficult to master and easy to cause problems in the road coarse aggregate detection, and the defects are mainly summarized in the following 4 aspects:
(1) Errors are caused by factors that polish the test piece: the polished test pieces manufactured by different personnel have uneven surface flatness, uneven aggregate gap size, extrusion phenomenon of bonding materials in the aggregate gap, and the like.
(2) The polishing performance error of the coarse aggregate is caused by the polishing performance test method: the method specifically comprises the following four aspects: first: the polishing performance of the polishing test piece is usually tested by adopting a swing value test method, the test process is not easy to control and is seriously influenced by human factors, the test steps are more, the process is tedious, and the time consumption is long. Second,: in the test process, the test piece is subjected to continuous vibration and extrusion for a long time, and the phenomena of particle falling, breakage and the like are very easy to occur. Third,: the swing value test method has low detection speed, and can only represent the friction coefficient at low speed (0-10 km/h) which is not consistent with the friction coefficient generated by actual high-speed running. Fourth,: the surface of the polished test piece is arc-shaped, the polished test piece is in arc-shaped friction when rubbed with the rubber sheet of the pendulum, the pressure value between the rubber sheet of the pendulum and the test block is a dynamic change value, and the plane friction state between the road surfaces is more important when the automobile brakes in road running, so that the friction coefficient error represented in the pendulum value test method is larger in the test of the road surface polishing performance, and the friction coefficient capable of representing the plane friction state is needed.
(3) The abrasion test method causes the abrasion performance error of coarse aggregates: the aggregate abrasion loss test is mostly adopted in the detection of the aggregate abrasion loss test, and the test adopts an external force impact test method to damage and destroy the sample, so that the test mode is too different from the use environment of the actual pavement aggregate, and the assessment method is further combined with the actual use environment.
(4) The existing assessment method has the following defects: the existing technical standards respectively provide a stipulation and evaluation method for the abrasion property and the polishing property of aggregate, but the evaluation results of a material with excellent performance on one hand and poor performance on the other hand can be contradictory and divergent.
Disclosure of Invention
The invention aims to provide equipment and a method for detecting and evaluating the abrasion and polishing performances of coarse aggregates, which can realize the rapid detection of the abrasion and polishing performances of the coarse aggregates, and the testing process is closer to the actual use process, the evaluation accuracy is higher, and the anti-polishing performances of the coarse aggregates are unified.
The invention adopts the technical scheme that:
an apparatus for detecting and evaluating abrasion and polishing performance of coarse aggregate comprises a base, a central processing unit, a servo motor and an abrasion and polishing performance detection assembly; the device also comprises an upright post, a force value sensor and a sample pressure regulating mechanism; the base is internally provided with a servo motor installation bin, the servo motor is fixedly arranged in the servo motor installation bin, and the input end of the servo motor is fixedly connected with the output end of the central processing unit; the abrasion and polishing performance detection assembly comprises a coarse grinding wheel, a fine grinding wheel and a pure rubber wheel; when the sample is subjected to rough grinding, the center of the rough grinding wheel is connected with the output end of the servo motor through a transmission shaft; when the sample is finely ground, the center of the fine grinding wheel is connected with the output end of the servo motor through a transmission shaft; when polishing performance detection is performed on the sample, the center of the pure rubber wheel is connected with the output end of the servo motor through a transmission shaft;
the upright post is perpendicular to the upper end surface of the base and is fixedly connected with the upper end surface of the base, the force value sensor is parallel to the upper bottom surface of the base, and one end of the force value sensor is fixedly connected with the side wall of the upright post; the sample pressure adjusting mechanism comprises weights, weight trays, ball linear slide rails and sliding connecting columns matched with the ball linear slide rails; the ball linear slide rail is perpendicular to the upper end surface of the base, is positioned above the abrasion and polishing performance detection assembly, and is fixedly connected with the other end of the force value sensor; the sliding connection column passes through the ball linear slide rail, the upper end face of the sliding connection column is fixedly connected with the lower end face of the weight disc, the lower end face of the sliding connection column is provided with a sample fixing groove, the groove wall of the sample fixing groove is provided with a pin hole, a sample is fixed in the sample fixing groove through a pin matched with the pin hole, and the lower end face of the sample is in contact with the upper end face of the coarse grinding wheel, the fine grinding wheel or the pure rubber wheel.
The device for detecting and evaluating the abrasion and polishing performance of the coarse aggregate further comprises a water spraying mechanism, wherein the water spraying mechanism comprises a spray head, a self-priming pump and a water storage device, the spray head is connected with the water storage device through the self-priming pump, and the spray head is arranged above the periphery of the sample fixing groove.
The device for detecting and evaluating the abrasion and polishing performance of the coarse aggregate is characterized in that the spray heads are duckbill spray heads, the number of the duckbill spray heads is multiple, and the specifications of the duckbill spray heads are different.
The device for detecting and evaluating the abrasion and polishing performance of the coarse aggregate is characterized in that the coarse grinding wheel is a brown corundum grinding wheel, and the fine grinding wheel is a green silicon carbide grinding wheel.
The sample fixing groove is a square groove.
A method for detecting and assessing coarse aggregate wear and polishing performance comprising the steps of:
1) Preparing a cuboid sample of coarse aggregate: selecting a coarse aggregate sample, and polishing the side surface of the coarse aggregate sample to be smooth, so that the coarse aggregate sample becomes a cuboid sample;
2) Abrasion performance test was performed on a rectangular parallelepiped sample:
a1: cleaning a cuboid sample, drying, and weighing the mass m of the cuboid sample 1 ；
a2: the method comprises the steps that a cuboid sample is filled into a sample fixing groove, the lower end face of the cuboid sample extends out of the sample fixing groove, and a pin penetrates through a pin hole to fix the cuboid sample in the sample fixing groove;
a3: the method comprises the steps that a worker fixedly connects an output shaft of a servo motor with the center of a rough grinding wheel through a transmission shaft, the lower end face of a cuboid sample is contacted with the outer edge of the upper end face of the rough grinding wheel, and rough grinding is carried out on the sample; setting the rotation time t of the rough grinding wheel in the central processing unit by staff 1 Duration t 1 Is a fixed value; the central processor controls the servo motor to start, the central controller controls the water spraying mechanism to start, and the central controller controls the servo motor to start at t 1 Stopping after that, and controlling the water spraying mechanism to be at t by the central controller 1 Stopping and taking down the rough grinding wheel;
a4: the staff fixedly connects the transmission shaft in the step a3 with the center of the fine grinding wheel, the lower end surface of the cuboid sample is contacted with the outer edge of the upper end surface of the fine grinding wheel, and the sample is finely ground; the staff sets the details in the CPUDuration t of rotation of grinding wheel 2 Duration t 2 Is a fixed value; the central processor controls the servo motor to start, the central controller controls the water spraying mechanism to start, and the central controller controls the servo motor to start at t 2 Stopping after that, and controlling the water spraying mechanism to be at t by the central controller 2 Stopping and taking down the fine grinding wheel; thus, qualified polishing samples are obtained;
a5: taking down the cuboid sample, namely polishing sample, and weighing the mass m of the polishing sample after drying 2 ；
a6: obtaining an abrasion value Q according to a formula (1), wherein the abrasion value Q represents the abrasion performance of the coarse aggregate:
the larger Q is, the worse the abrasion performance of the coarse aggregate is, the less abrasion-resistant the coarse aggregate is;
the smaller Q is, the better the abrasion performance of the coarse aggregate is, and the more abrasion-resistant the coarse aggregate is;
3) Polishing test of polished sample in step a4:
s1: filling a polishing sample into the sample fixing groove, enabling the lower end surface of the polishing sample to extend out of the sample fixing groove, and enabling a pin to pass through a pin hole to fix the polishing sample in the sample fixing groove; fixedly connecting the transmission shaft in the step a4 with the center of the pure rubber wheel, and enabling the lower end face of the polished sample to contact with the outer edge of the upper end face of the pure rubber wheel;
s2: quantitative weights are added into a weight tray of the sample pressure adjusting mechanism, and the vertical pressure N between the pure rubber wheel and the polished sample is obtained according to the mass of the weights 1 Divided into vertical pressure N 1 Is a fixed value; according to the mass of the sample pressure regulating mechanism, the vertical pressure N between the pure rubber wheel and the polished sample is obtained 2 Divided into vertical pressure N 1 +vertical pressure N 2 Obtaining vertical pressure N between the pure rubber wheel and the polished sample;
s3: the central processing unit controls the servo motor to start, and the force value sensor collects a first horizontal friction force F between the polishing sample and the pure rubber wheel, which corresponds to the vertical pressure N, and transmits the first horizontal friction force F to the central processing unit;
s4: obtaining a first buffing value P according to formula (2), the first buffing value P characterizing the buffing performance of the coarse aggregate:
the larger P is, the better polishing performance of the coarse aggregate is indicated, and the more antiskid the coarse aggregate is;
the smaller P is, the worse the polishing performance of the coarse aggregate is, and the less the coarse aggregate is antiskid;
4) Obtaining a coarse aggregate wear index M according to the wear values Q and the polishing values P obtained in the step 2) and the step 3) by utilizing a formula (3), wherein the coarse aggregate wear index M represents the comprehensive performance of the coarse aggregate;
the smaller M is, the poor comprehensive performance of the coarse aggregate is indicated;
the larger M is, the better the comprehensive performance of the coarse aggregate is;
further, in the substep S3 of the step 3, when the central processing unit controls the servo motor to start, the staff controls the water spraying mechanism to start, the water spraying mechanism sprays water, a water film is formed between the pure rubber wheel and the polished sample, and the force value sensor collects a second horizontal friction force F corresponding to the vertical pressure N between the polished sample and the pure rubber wheel under the condition that the water film exists 1 And apply a second horizontal friction force F 1 Transmitting to the CPU, the CPU obtains a second polishing value P according to the formula (4) 1 Second polishing value P 1 Characterization of the polishing properties of coarse aggregates with water on the surface:
further, the steps 2) and 3) are repeated respectivelyRepeating n times to obtain n sub-abrasion values Q of the cuboid sample 1 、Q 2 …Q n First polishing value P of n number of polishing samples 1 、P 2 …P n The abrasion value Q is equal to n sub-abrasion values Q of the cuboid sample 1 、Q 2 …Q n The first polishing value P is equal to n sub-first polishing values P of the polishing sample 1 、P 2 …P n Average value of (2).
The invention utilizes the grinding of the coarse grinding wheel and the fine grinding wheel to simulate the grinding of the wheel on the aggregate, is closer to the actual abrasion process of the aggregate, solves the problem that the difference between the testing mode in the los Angeles abrasion loss test and the use environment of the actual pavement aggregate is too large, and improves the assessment precision of the abrasion test; the grinding process of the coarse grinding wheel and the fine grinding wheel on the aggregate is high in efficiency, and the grinding process is fixed, so that the quality is stable, the working efficiency of aggregate grinding property detection is improved, and the problem of uneven quality of grinding test pieces manufactured by different personnel is solved;
the horizontal friction force between the rubber wheel and the aggregate is directly detected by the force value sensor, and the friction coefficient between the aggregate and the rubber wheel is reversely calculated according to the vertical loading. The abrasion loss of the test sample is measured by adopting a horizontal friction mode and is consistent with the action environment of the wheels and the road surface when the brake is carried out in the actual road condition, and the test result has more reference value; and the manual errors of different personnel operating the pendulum instrument are solved, the equipment detection data are stable, the automatic operation is realized, the time and the labor are saved, and the pendulum instrument has good economic benefit and wide application prospect.
Drawings
FIG. 1 is a schematic view of the apparatus for detecting and assessing coarse aggregate wear and polishing performance of the present invention;
FIG. 2 is a schematic diagram of a sample pressure adjustment mechanism according to the present invention;
FIG. 3 is a flow chart of a method of the present invention for detecting and assessing coarse aggregate wear and polishing performance.
Detailed Description
As shown in fig. 1 and 2, the present invention includes a base 1, a central processing unit, a servo motor 2, and a wear and abrasion performance detecting module 3; the device also comprises an upright post 4, a force value sensor 5 and a sample pressure regulating mechanism; the base 1 is internally provided with a servo motor installation bin, the servo motor 2 is fixedly arranged in the servo motor installation bin, and the input end of the servo motor 2 is fixedly connected with the output end of the central processing unit; the abrasion and polishing performance detection assembly 3 comprises a coarse grinding wheel, a fine grinding wheel and a pure rubber wheel; when the sample 10 is subjected to rough grinding, the center of the rough grinding wheel is connected with the output end of the servo motor 2 through a transmission shaft; when the sample 10 is finely ground, the center of the fine grinding wheel is connected with the output end of the servo motor 2 through a transmission shaft; when polishing performance detection is carried out on the sample 10, the center of the pure rubber wheel is connected with the output end of the servo motor 2 through a transmission shaft;
the invention utilizes the grinding of the coarse grinding wheel and the fine grinding wheel to simulate the grinding of the wheel on the aggregate, is closer to the actual abrasion process of the aggregate, solves the problem that the difference between the testing mode in the los Angeles abrasion loss test and the use environment of the actual pavement aggregate is too large, and improves the assessment precision of the abrasion test; the grinding process of the coarse grinding wheel and the fine grinding wheel on the aggregate is high in efficiency, and the grinding process is fixed, so that the quality is stable, the working efficiency of aggregate grinding property detection is improved, and the problem of uneven quality of grinding test pieces manufactured by different personnel is solved;
the upright post 4 is perpendicular to the upper end face of the base 1 and is fixedly connected with the upper end face of the base 1, the force value sensor 5 is parallel to the upper bottom face of the base 1, and one end of the force value sensor 5 is fixedly connected with the side wall of the upright post 4; the sample pressure adjusting mechanism comprises a weight 6, a weight tray 7, a ball linear slide rail 9 and a sliding connecting column 8 matched with the ball linear slide rail 9; the ball linear slide rail 9 is perpendicular to the upper end surface of the base 1, is positioned above the abrasion and polishing performance detection assembly 3, and is fixedly connected with the other end of the force value sensor 5; the sliding connection column 8 passes through the ball linear slide rail 9, the upper end face of the sliding connection column 8 is fixedly connected with the lower end face of the weight disc 7, the sliding connection column 8 is provided with a sample fixing groove at the lower end face, a sample fixing groove is not shown in the drawing, a pin hole is formed in the groove wall of the sample fixing groove, the sample 10 is fixed in the sample fixing groove through a pin 81 matched with the pin hole, and the lower end face of the sample 10 is contacted with the upper end face of the coarse grinding wheel, the fine grinding wheel or the pure rubber wheel.
The friction between the ball linear rail 9 and the sliding connection post 8 is small and is negligible in the present invention. Along with the abrasion of the lower end face of the sample 10 by the coarse grinding wheel or the fine grinding wheel, the sliding connecting column 8 can move downwards easily under the action of the weight 6, so that the lower end face of the sample 10 is always contacted with the upper end face of the coarse grinding wheel, the fine grinding wheel or the pure rubber wheel in the coarse grinding, the fine grinding and the polishing test.
Compared with the traditional polishing performance test method, the method has the advantages that the motor is adopted to drive the pure rubber wheel, the force value sensor 5 is utilized to directly detect the horizontal friction force between the rubber wheel and the aggregate during rotation, and the friction coefficient between the aggregate and the rubber wheel is reversely calculated according to vertical loading. The polishing test of the test sample 10 is carried out in a horizontal friction mode, the action environment of the wheels and the road surface is consistent with that of the brake in the actual road condition, and the test result has more reference value; and the manual errors of different personnel operating the pendulum instrument are solved, the equipment detection data are stable, the automatic operation is realized, the time and the labor are saved, and the pendulum instrument has good economic benefit and wide application prospect.
The device for detecting and evaluating the abrasion and polishing performance of the coarse aggregate further comprises a water spraying mechanism, wherein the water spraying mechanism comprises a spray head 11, a self-priming pump 12 and a water storage device 13, the spray head 11 is connected with the water storage device 13 through the self-priming pump 12, and the spray head 11 is arranged above the periphery of the sample fixing groove.
The water spraying mechanism has two functions, namely, firstly, when the coarse grinding wheel or the fine grinding wheel grinds the aggregate sample 10, water is sprayed to prevent aggregate powder from flying and reduce heat generated by friction between the sample 101 and the coarse grinding wheel or the fine grinding wheel; secondly, water is sprayed when the rubber wheel rotates, a water film is formed between the pure rubber wheel and the sample 10, and the friction coefficient between the wheel and the road surface in rainy days is simulated.
The spray heads 11 are duckbill spray heads 11, the number of the duckbill spray heads 11 is multiple, and the specifications of the duckbill spray heads 11 are different. The operator selects the duckbill spray head 11 of a proper specification according to the actual situation and manually replaces the duckbill spray head.
The coarse grinding wheel is a brown corundum grinding wheel, and the fine grinding wheel is a green silicon carbide grinding wheel. Coarse grinding is carried out on the test piece by using a brown alumina grinding wheel, and fine grinding is carried out on the test piece by using a green silicon carbide grinding wheel.
The sample fixing groove is a square groove. In the process of fixing the sample 10, the shape of the sample 10 is required to be matched with the shape of the sample fixing groove, and the cuboid sample 10 is simple to manufacture, so that the sample fixing groove is provided with a square groove.
As shown in fig. 3, a method for detecting and assessing coarse aggregate wear and polishing performance, comprising the steps of:
1) Cuboid sample 10 of coarse aggregate was prepared: selecting a coarse aggregate sample, and polishing the side surface of the coarse aggregate sample to be smooth, so that the coarse aggregate sample becomes a cuboid sample 10;
2) Abrasion performance test was performed on the rectangular parallelepiped sample 10:
a1: cleaning a cuboid sample 10, drying, and weighing the cuboid sample 10 mass m 1 ；
a2: the cuboid sample 10 is loaded into the sample fixing groove, the lower end surface of the cuboid sample 10 extends out of the sample fixing groove, and the pin 81 penetrates through the pin hole to fix the cuboid sample 10 in the sample fixing groove;
a3: the method comprises the steps that a worker fixedly connects an output shaft of a servo motor with the center of a rough grinding wheel through a transmission shaft, the lower end face of a cuboid sample is contacted with the outer edge of the upper end face of the rough grinding wheel, and rough grinding is carried out on the sample; setting the rotation time t of the rough grinding wheel in the central processing unit by staff 1 Duration t 1 Is a fixed value; the central processor controls the servo motor to start, the central controller controls the water spraying mechanism to start, and the central controller controls the servo motor to start at t 1 Stopping after that, and controlling the water spraying mechanism to be at t by the central controller 1 Stopping and taking down the rough grinding wheel;
a4: the staff fixedly connects the transmission shaft in the step a3 with the center of the fine grinding wheel, the lower end surface of the cuboid sample is contacted with the outer edge of the upper end surface of the fine grinding wheel, and the sample is finely ground; the staff sets the rotation time t of the fine grinding wheel in the CPU 2 Duration t 2 Is a fixed value; the central processor controls the servo motor to start, the central controller controls the water spraying mechanism to start, and the central controller controls the servo motor to start at t 2 Stopping after that, and controlling the water spraying mechanism to be at t by the central controller 2 Stopping and taking down the fine grinding wheel; thus, qualified polishing samples are obtained;
a5: taking down the rectangular parallelepiped sample 10, namely polishing sample 10, and weighing the mass m of polishing sample 10 after drying 2 ；
a6: obtaining an abrasion value Q according to a formula (1), wherein the abrasion value Q represents the abrasion performance of the coarse aggregate:
the larger Q is, the worse the abrasion performance of the coarse aggregate is, the less abrasion-resistant the coarse aggregate is;
the smaller Q is, the better the abrasion performance of the coarse aggregate is, and the more abrasion-resistant the coarse aggregate is;
in step 2), the abrasion performance test of the samples of different coarse aggregates is performed by a controlled variable method, i.e. a time period t 1 And a time length t 2 For a fixed value, the motor rotation speed is a fixed value, and the mass m of the cuboid sample 10 1 Equal. Duration t 1 And a time length t 2 Is set by the staff according to experience: duration t 1 The micro-texture of the lower end surface of the cuboid sample 10 is required to be completely polished, the abrasion depth of the lower end surface is preferably 3mm-6mm, and the rough polishing time t1 is determined; the abrasion depth loss of the lower end face of the cuboid sample 10 is 1-2mm in time t 2;
3) Polishing test for polished sample 10 in step a4:
s1: loading the polishing sample 10 into a sample fixing groove, extending the lower end surface of the polishing sample 10 out of the sample fixing groove, and fixing the polishing sample 10 in the sample fixing groove by a pin 81 penetrating through a pin hole; fixedly connecting the transmission shaft in the step a4 with the center of a pure rubber wheel, and enabling the lower end face of the polishing sample 10 to contact with the outer edge of the upper end face of the pure rubber wheel;
s2: a quantitative weight 6 is added in a weight tray 7 of the sample pressure adjusting mechanism,based on the mass of the weight 6, a partial vertical pressure N between the plain rubber wheel and the polished sample 10 is obtained 1 Divided into vertical pressure N 1 Is a fixed value; according to the mass of the sample pressure regulating mechanism, the vertical pressure N between the pure rubber wheel and the polished sample 10 is obtained 2 Divided into vertical pressure N 1 +vertical pressure N 2 The vertical pressure N between the plain rubber wheel and the polished sample 10 is obtained; in this step, the control variable method is also adopted, so that the motor rotation speed is kept equal and the vertical pressure N is also kept equal when different samples 10 are subjected to polishing tests; according to the standard, the pressure of the tires of the load-carrying vehicle to the ground is controlled within 0.7MPa, the influence of the self bearing of the grinding wheel is comprehensively considered, and the vertical pressure N is controlled within 20N.
S3: the central processing unit controls the servo motor 2 to start, and the force value sensor 5 collects a first horizontal friction force F between the polishing sample 10 and the pure rubber wheel, which corresponds to the vertical pressure N, and transmits the first horizontal friction force F to the central processing unit; s4: obtaining a first buffing value P according to formula (2), the first buffing value P characterizing the buffing performance of the coarse aggregate:
the larger P is, the better polishing performance of the coarse aggregate is indicated, and the more antiskid the coarse aggregate is;
the smaller P is, the worse the polishing performance of the coarse aggregate is, and the less the coarse aggregate is antiskid;
4) Obtaining a coarse aggregate wear resistance index M according to the abrasion value Q and the first polishing value P obtained in the step 2) and the step 3) by utilizing a formula (3), wherein the coarse aggregate wear resistance index M represents the comprehensive performance of the coarse aggregate;
in the field of coarse aggregates, the abrasion value Q and the first polishing value P are normally positively correlated, i.e. the smaller the abrasion value Q, the more abrasive the coarse aggregate is resistant to abrasion, the larger the first polishing value P, the more slip-resistant the coarse aggregate, and generally no material such as glass will appear with a very large abrasion value Q and a very small first polishing value P.
Therefore, in essence, the coarse aggregate wear-resistance index M further characterizes the comprehensive performance of the coarse aggregate, namely, the smaller the coarse aggregate wear-resistance index M is, the poor comprehensive performance of the coarse aggregate is indicated, and the larger the coarse aggregate wear-resistance index M is, the better the comprehensive performance of the coarse aggregate is indicated;
in order to further explain the meaning of the abrasion resistance index M of the coarse aggregate, assuming that the abrasion values Q of the first coarse aggregate and the second coarse aggregate are equal, when the abrasion resistance index M of the first coarse aggregate is smaller than the abrasion resistance index M of the second coarse aggregate, the first polishing value P of the first coarse aggregate is smaller than the first polishing value P of the second coarse aggregate, and the comprehensive performance of the second coarse aggregate is good;
assuming that the first polishing value P of the first coarse aggregate is equal to that of the second coarse aggregate, when the abrasion resistance index M of the first coarse aggregate is smaller than that of the second coarse aggregate, the abrasion resistance index M of the first coarse aggregate is larger than that of the first polishing value P of the second coarse aggregate, and the comprehensive performance of the second coarse aggregate is good.
In the method for detecting and evaluating the abrasion and polishing performance of coarse aggregate, in the substep S3 of the step 3, when the central processor controls the servo motor 2 to start, the staff controls the water spraying mechanism to start, the water spraying mechanism sprays water to form a water film between the pure rubber wheel and the polishing sample 10, and the force value sensor 5 collects a second horizontal friction force F corresponding to the vertical pressure N between the polishing sample 10 and the pure rubber wheel under the condition of the water film 1 And apply a second horizontal friction force F 1 Transmitting to the CPU, the CPU obtains a second polishing value P according to the formula (4) 1 Second polishing value P 1 Characterization of the polishing properties of coarse aggregates with water on the surface:
the method for detecting and evaluating the abrasion and polishing performance of the coarse aggregate is characterized by comprising the following steps of: the steps 2) and 3) are repeated for n times respectively to obtain a cuboid sample 1N number of sub-wear values Q of 0 1 、Q 2 …Q n N number of sub-first polishing values P of polishing sample 10 1 、P 2 …P n The abrasion value Q is equal to n sub-abrasion values Q of the rectangular parallelepiped test piece 10 1 、Q 2 …Q n The first polishing value P is equal to n sub-first polishing values P of the polishing sample 10 1 、P 2 …P n Average value of (2).
The abrasion value Q and the first polishing value P are more accurate by means of multiple measurement and averaging, and the accuracy of the method for detecting and evaluating the abrasion and polishing performance of the coarse aggregate is further improved.
Claims (6)
1. A method for detecting and assessing coarse aggregate wear and polishing performance, characterized by:
the polishing machine comprises a base, a central processing unit, a servo motor and a wear and polishing performance detection assembly; the device also comprises an upright post, a force value sensor and a sample pressure regulating mechanism; the base is internally provided with a servo motor installation bin, the servo motor is fixedly arranged in the servo motor installation bin, and the input end of the servo motor is fixedly connected with the output end of the central processing unit; the abrasion and polishing performance detection assembly comprises a coarse grinding wheel, a fine grinding wheel and a pure rubber wheel; when the sample is subjected to rough grinding, the center of the rough grinding wheel is connected with the output end of the servo motor through a transmission shaft; when the sample is finely ground, the center of the fine grinding wheel is connected with the output end of the servo motor through a transmission shaft; when polishing performance detection is performed on the sample, the center of the pure rubber wheel is connected with the output end of the servo motor through a transmission shaft;
the upright post is perpendicular to the upper end surface of the base and is fixedly connected with the upper end surface of the base, the force value sensor is parallel to the upper bottom surface of the base, and one end of the force value sensor is fixedly connected with the side wall of the upright post; the sample pressure adjusting mechanism comprises weights, weight trays, ball linear slide rails and sliding connecting columns matched with the ball linear slide rails; the ball linear slide rail is perpendicular to the upper end surface of the base, is positioned above the abrasion and polishing performance detection assembly, and is fixedly connected with the other end of the force value sensor; the sliding connecting column penetrates through the ball linear slide rail, the upper end face of the sliding connecting column is fixedly connected with the lower end face of the weight disc, the lower end face of the sliding connecting column is provided with a sample fixing groove, the groove wall of the sample fixing groove is provided with a pin hole, a sample is fixed in the sample fixing groove through a pin matched with the pin hole, and the lower end face of the sample is contacted with the upper end face of the coarse grinding wheel, the fine grinding wheel or the pure rubber wheel;
the water spraying mechanism comprises a spray head, a self-priming pump and a water storage device, wherein the spray head is connected with the water storage device through the self-priming pump, and the spray head is arranged above the periphery of the sample fixing groove;
the method comprises the following steps:
1) Preparing a cuboid sample of coarse aggregate: selecting a coarse aggregate sample, and polishing the side surface of the coarse aggregate sample to be smooth, so that the coarse aggregate sample becomes a cuboid sample;
2) Abrasion performance test was performed on a rectangular parallelepiped sample:
a1: cleaning a cuboid sample, drying, and weighing the mass of the cuboid samplem 1 ；
a2: the method comprises the steps that a cuboid sample is filled into a sample fixing groove, the lower end face of the cuboid sample extends out of the sample fixing groove, and a pin penetrates through a pin hole to fix the cuboid sample in the sample fixing groove;
a3: the method comprises the steps that a worker fixedly connects an output shaft of a servo motor with the center of a rough grinding wheel through a transmission shaft, the lower end face of a cuboid sample is contacted with the outer edge of the upper end face of the rough grinding wheel, and rough grinding is carried out on the sample; setting the rotation time t of the rough grinding wheel in the central processing unit by staff 1 Duration t 1 Is a fixed value; the central processor controls the servo motor to start, the central controller controls the water spraying mechanism to start, and the central controller controls the servo motor to start at t 1 Stopping after that, and controlling the water spraying mechanism to be at t by the central controller 1 Stopping and taking down the rough grinding wheel;
a4: the staff fixedly connects the transmission shaft in the step a3 with the center of the fine grinding wheel, the lower end surface of the cuboid sample is contacted with the outer edge of the upper end surface of the fine grinding wheel, and the sample is finely ground; the staff sets the rotation time t of the fine grinding wheel in the CPU 2 Duration t 2 Is a fixed value; the central processor controls the servo motor to start, the central controller controls the water spraying mechanism to start, and the central controller controls the servo motor to start at t 2 Stopping after that, and controlling the water spraying mechanism to be at t by the central controller 2 Stopping and taking down the fine grinding wheel; thus, qualified polishing samples are obtained;
a5: taking down the cuboid sample, namely polishing sample, and weighing the mass of the polishing sample after dryingm 2 ；
a6: obtaining an abrasion value Q according to a formula (1), wherein the abrasion value Q represents the abrasion performance of the coarse aggregate:
𝑄=（𝑚 1 −𝑚 2 ）/ 𝑚 1 ×100% （1）
the larger Q is, the worse the abrasion performance of the coarse aggregate is, the less abrasion-resistant the coarse aggregate is;
the smaller Q is, the better the abrasion performance of the coarse aggregate is, and the more abrasion-resistant the coarse aggregate is;
3) Polishing test of polished sample in step a4:
s1: filling a polishing sample into the sample fixing groove, enabling the lower end surface of the polishing sample to extend out of the sample fixing groove, and enabling a pin to pass through a pin hole to fix the polishing sample in the sample fixing groove; fixedly connecting the transmission shaft in the step a4 with the center of the pure rubber wheel, and enabling the lower end face of the polished sample to contact with the outer edge of the upper end face of the pure rubber wheel;
s2: quantitative weights are added into a weight tray of the sample pressure adjusting mechanism, and the vertical pressure N between the pure rubber wheel and the polished sample is obtained according to the mass of the weights 1 Divided into vertical pressure N 1 Is a fixed value; according to the mass of the sample pressure regulating mechanism, the vertical pressure N between the pure rubber wheel and the polished sample is obtained 2 Divided into vertical pressure N 1 +vertical pressure N 2 Obtaining vertical pressure N between the pure rubber wheel and the polished sample;
s3: the central processing unit controls the servo motor to start, and the force value sensor collects a first horizontal friction force F between the polishing sample and the pure rubber wheel, which corresponds to the vertical pressure N, and transmits the first horizontal friction force F to the central processing unit;
s4: obtaining a first buffing value P according to formula (2), the first buffing value P characterizing the buffing performance of the coarse aggregate:
𝑃= F/N （2）
the larger P is, the better polishing performance of the coarse aggregate is indicated, and the more antiskid the coarse aggregate is;
the smaller P is, the worse the polishing performance of the coarse aggregate is, and the less the coarse aggregate is antiskid;
4) Obtaining a coarse aggregate wear index M according to the wear values Q and the polishing values P obtained in the step 2) and the step 3) by utilizing a formula (3), wherein the coarse aggregate wear index M represents the comprehensive performance of the coarse aggregate;
M=P/Q ×100% （3）
the smaller M is, the poor comprehensive performance of the coarse aggregate is indicated;
the larger M indicates the better comprehensive performance of the coarse aggregate.
2. The method for detecting and assessing coarse aggregate wear and abrasion performance of claim 1, wherein: in the substep S3 of the step 3), when the central processing unit controls the servo motor to start, the staff controls the water spraying mechanism to start, the water spraying mechanism sprays water to form a water film between the pure rubber wheel and the polished sample, and the force value sensor collects a second horizontal friction force between the polished sample and the pure rubber wheel corresponding to the vertical pressure N under the condition of the water film𝐹 1 And apply a second level of friction𝐹 1 Transmitting to the CPU, the CPU obtaining a second polishing value according to formula (4)𝑃 1 Second polishing value𝑃 1 Characterization of the polishing properties of coarse aggregates with water on the surface:
𝑃 1 =𝐹 1 /𝑁 （4）。
3. the method for detecting and assessing coarse aggregate wear and abrasion performance of claim 1, wherein: the step 2) and the step 3) are respectively repeated for n times to obtain n sub-abrasion values Q of the cuboid sample 1 、Q 2 … Qn, n number of sub-first polishing values P of polishing sample 1 、P 2 …P n The abrasion value Q is equal to n sub-abrasion values Q of the cuboid sample 1 、Q 2 …Q n The first polishing value P is equal to n sub-first polishing values P of the polishing sample 1 、P 2 …P n Average value of (2).
4. The method for detecting and assessing coarse aggregate wear and abrasion performance of claim 1, wherein: the duckbill type spray head is characterized in that the spray heads are duckbill spray heads, the number of the duckbill spray heads is multiple, and the specifications of the duckbill spray heads are different.
5. The method for detecting and assessing coarse aggregate wear and abrasion performance of claim 1, wherein: the coarse grinding wheel is a brown corundum grinding wheel, and the fine grinding wheel is a green silicon carbide grinding wheel.
6. The method for detecting and assessing coarse aggregate wear and abrasion performance of claim 1, wherein: the sample fixing groove is a square groove.
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| CN109580407B (en) * | 2018-11-13 | 2022-04-08 | 葛洲坝集团交通投资有限公司 | Method for measuring wear resistance of pavement coarse aggregate |
| CN111665147B (en) * | 2020-06-09 | 2022-10-11 | 山西交通职业技术学院 | Method for measuring impact value of coarse aggregate based on vibration compaction method |
| CN113466076A (en) * | 2021-07-28 | 2021-10-01 | 广东长亨石业有限公司 | Abrasion device and test method for machine-made sand test piece |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201083664Y (en) * | 2007-08-07 | 2008-07-09 | 广东轻工职业技术学院 | Material friction wear properties tester |
| CN201368833Y (en) * | 2009-03-27 | 2009-12-23 | 长安大学 | Road surface accelerated wear testing apparatus |
| CN102680218A (en) * | 2012-04-25 | 2012-09-19 | 中国铁道科学研究院金属及化学研究所 | Test table for polishing sand wheel and test method using same |
| CN102944512A (en) * | 2012-11-03 | 2013-02-27 | 中国矿业大学 | Test machine and test method for real-time and dynamic observation of end surface torsion friction and abrasion of friction interface |
| CN104122158A (en) * | 2014-07-03 | 2014-10-29 | 开封恒锐新金刚石制品有限公司 | Cutting line grinding test device and test method |
| CN104237038A (en) * | 2014-09-03 | 2014-12-24 | 北京科技大学 | Friction load coupling experimental device and friction load coupling experimental method in marine climate environment |
| CN104502215A (en) * | 2015-01-08 | 2015-04-08 | 攀钢集团研究院有限公司 | Wear test device and wear test method |
| CN107350970A (en) * | 2017-05-12 | 2017-11-17 | 河南理工大学 | A kind of ELID emery wheels oxide-film coefficient of friction on-line measurement, ELID grindings, polishing all-in-one |
-
2017
- 2017-12-01 CN CN201711246469.3A patent/CN107907438B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201083664Y (en) * | 2007-08-07 | 2008-07-09 | 广东轻工职业技术学院 | Material friction wear properties tester |
| CN201368833Y (en) * | 2009-03-27 | 2009-12-23 | 长安大学 | Road surface accelerated wear testing apparatus |
| CN102680218A (en) * | 2012-04-25 | 2012-09-19 | 中国铁道科学研究院金属及化学研究所 | Test table for polishing sand wheel and test method using same |
| CN102944512A (en) * | 2012-11-03 | 2013-02-27 | 中国矿业大学 | Test machine and test method for real-time and dynamic observation of end surface torsion friction and abrasion of friction interface |
| CN104122158A (en) * | 2014-07-03 | 2014-10-29 | 开封恒锐新金刚石制品有限公司 | Cutting line grinding test device and test method |
| CN104237038A (en) * | 2014-09-03 | 2014-12-24 | 北京科技大学 | Friction load coupling experimental device and friction load coupling experimental method in marine climate environment |
| CN104502215A (en) * | 2015-01-08 | 2015-04-08 | 攀钢集团研究院有限公司 | Wear test device and wear test method |
| CN107350970A (en) * | 2017-05-12 | 2017-11-17 | 河南理工大学 | A kind of ELID emery wheels oxide-film coefficient of friction on-line measurement, ELID grindings, polishing all-in-one |
Non-Patent Citations (2)
| Title |
|---|
| 沥青混凝土防滑磨耗层防滑性能加速试验方法的研究;杨众 等;华东公路(第135期);第50-54页 * |
| 粗集料磨耗试验方法讨论;成全喜;科技资讯(第07期);第116页 * |
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