Road and bridge deck concrete abrasion impact composite damage testing device and testing method

Abstract

The invention relates to the technical field related to concrete tests, in particular to a road and bridge deck concrete abrasion impact composite damage testing device and method.The device comprises a device body and device accessories, and the device body is a concrete abrasion impact testing machine; the device accessories are a high-power dust collector, a digital display control instrument, a small ball fixing clamp, an impact steel ball, an impacted small ball and a concrete mold. The testing method comprises the following steps: pouring a test block by using a concrete mold according to a concrete mixing proportion; fixing the test block maintained to the target age by using a fixing clamp, and carrying out wear test on the test block by using a wear test module; the drop hammer impact test module is used for carrying out impact test on the test block, and the wear impact composite test can be realized by switching the function switching test module through the device.

Description

Technical Field

[0001] The invention relates to the technical field related to concrete testing, and in particular to a device and method for testing composite damage of road and bridge deck concrete caused by wear and impact. Background Art

[0002] In civil engineering construction, road and bridge decks are usually subjected to wear and impact damage from vehicles and other vehicles. These damages generally cause composite damage and fatigue damage to the concrete of road and bridge decks. After wear and impact damage, concrete cracks, peeling and potholes appear on the surface of the road and bridge deck, which need to be repaired, seriously affecting the service performance and service life of the road and bridge deck concrete. It is particularly necessary to study the wear and impact resistance of road and bridge deck concrete, especially the damage form and composite damage fatigue number of concrete after wear and impact composite damage.

[0003] The current wear and impact resistance specifications for road and bridge deck concrete have separate requirements for concrete wear resistance and impact resistance, but road and bridge deck concrete usually faces combined damage from wear and impact, and wear damage and impact damage aggravate each other. Wear damage causes the concrete surface to peel off, fibers to be exposed, and aggregates to protrude. The concrete materials no longer have adhesion and synergy, and the concrete's impact resistance performance is significantly reduced; impact damage causes concrete cracking and surface depressions, and the interior of the concrete is exposed after damage. When the vehicle is worn, the interior of the concrete can be damaged through the defects left by the impact. Considering the wear resistance and impact resistance of concrete alone has great limitations. At present, the test equipment for wear and impact of road and bridge deck concrete is only a single test. Different devices have different requirements for concrete test blocks, test surfaces, and test methods. This type of device cannot achieve concrete wear and impact combined damage testing.

[0004] In order to facilitate the testing of concrete wear resistance and impact resistance in road and bridge deck construction site laboratories and scientific research institution laboratories, it is particularly necessary to develop a set of road and bridge deck concrete wear resistance and impact resistance testing equipment that is mature and stable, simple to operate, compact in structure, fast and efficient. Summary of the invention

[0005] The purpose of the present invention is to provide a test device and a test method for wear and impact composite damage of road and bridge deck concrete. The device can effectively simulate the wear damage and impact damage of common vehicles on road and bridge deck concrete, provide ideal experimental conditions for testing the wear resistance and impact resistance of concrete, and reveal the rules of improving the wear resistance and impact resistance of concrete by different methods such as strengthening, toughening and increasing bonding strength through studying the wear and impact damage mode and fatigue times of road and bridge deck concrete, so as to provide solid support for scientific research and technological innovation in the field of concrete wear resistance and impact resistance.

[0006] The present invention achieves the above-mentioned purpose by adopting the following technical scheme: providing a road bridge deck concrete wear and impact composite damage testing device, the device comprising a testing device body and a testing device accessory,

[0007] The test device body comprises a main body and a test bench, a concrete test block fixing fixture is arranged on the test bench, a wear motor is arranged behind the main body, the wear motor transmits torque to the detachable transmission shaft inside the column through a transmission shaft installed inside the main body, the column and the gear box transmit torque to the gear set inside the gear box through a detachable transmission shaft, the column and the gear box are connected through a variable bayonet concentric locking device, the variable bayonet concentric locking device can be unlocked by pulling the lock buckle upward, the gear box can be rotated by turning the handle, the counterweight plate is installed on the gear box and loaded on the main shaft, the torque is transmitted to the main shaft by the gear box, the main shaft drives the grinding head to rotate, a wear gear is installed on the grinding head, a telescopic sleeve is provided outside the main shaft for protection, the height of the drop hammer magnetic suction head is adjusted by a ruler, and the height of the drop hammer magnetic suction head can be fixed by tightening the locking rotary rod;

[0008] The test device accessories include a concrete test block mold, a vacuum cleaner, a suction head, a CNC box, a steel ball, a cover plate and a steel ball. The vacuum cleaner uses the suction head to clean the debris or fragments of concrete peeling caused by wear or impact tests. The CNC box is connected to the main body through a cable. The digital display screen displays the current test items. The button start and stop device, the test items and the test mode are switched, and the steel ball or hammer impacts the concrete test block. The cover plate is used to fix the small steel ball to be impacted during the impact test. The small steel ball transfers the load to the concrete test block under the impact of the steel ball or the falling hammer.

[0009] The concrete test block fixing fixture is composed of a fixture positioning mark and a fixing knob.

[0010] The concrete test block mold has a size of Φ150mm×50mm and is made of steel or plastic.

[0011] The mass of the steel ball is 4.5 kg.

[0012] The testing method applicable to the road and bridge deck concrete wear and impact composite damage testing device comprises the following steps:

[0013] (1) Prepare concrete according to the mix ratio and pour it into the concrete test block mold;

[0014] (2) Curing the test pieces to the specified age;

[0015] (3) Conduct a single wear test, a single impact test, or a combined wear and impact test.

[0016] The separate wear test is to place the test block on the main test bench, fix the test block in the working position with the concrete test block fixing fixture, pull up the lock buckle to unlock the variable bayonet concentric locking device, swing and rotate the handle to make the gear box drive the main shaft to align with the working position, adjust the use of one or two counterweight plates according to the test requirements, set the CNC box, press the test preparation button, the transmission shaft outputs the test preparation torque to make the main shaft fall to the working position, the grinding head with the worn gear contacts the surface of the test block, select the time test or the number of laps test according to the test requirements, press the CNC box button to adjust the test time length or the number of test laps, press the start button to perform a wear test on the concrete test block, turn on the vacuum cleaner and use the suction head to clean the debris caused by the wear of the concrete without large fragments, and record the data as follows:

[0017] Record the following data at the initial wear (normal use limit), and do not record if it does not appear;

[0018]

[0019]

[0020] The following data are recorded when the damage occurs (working service limit), and no data is recorded if it does not occur;

[0021] <![CDATA[Cumulative number of wear times N cβ > <![CDATA[Cumulative damage mass G cβ > i＝β b

[0022]

[0023] Where N cα N is the limit damage times for normal use. cβ is the number of damages in service, G c The damage amount is kg / m 2 , G i is the damage amount of the ith test kg / m 2 , m1 is the mass of the specimen before the test (kg), m2 is the mass of the specimen after the test (kg), A is the damaged area of ​​the specimen (m 2 , α and β are the number of normal use limit damage and working service limit damage, a and b are the mass of normal use limit damage and working service limit damage, respectively;

[0024] The single impact test is to place the test block on the main test bench, use the concrete test block fixing fixture to place the test block in the working position, align the drop hammer magnetic suction head with the working position, adjust the ruler height so that the drop hammer reaches the required height for the predetermined impact energy, tighten the locking rod to fix the height of the drop hammer magnetic suction head, adsorb the steel ball or hammer head on the drop hammer magnetic suction head, complete the drop hammer preparation, adjust the concrete test block fixing fixture knob so that the concrete fixture is located at the calibration position, completely fit the cover plate on the concrete test block fixing fixture, put a small steel ball in the middle hole, complete the concrete test block impact preparation, select single or multiple impacts according to the test requirements, press the CNC box button to start the impact test, after the single impact is completed, restore the small steel ball impact position, install the steel ball or hammer head back on the drop hammer magnetic suction head, and then perform the impact test again. The recorded data is as follows:

[0025] When the initial crack occurs (normal use limit), record the following data, if it does not occur, do not record;

[0026]

[0027] The following data are recorded when the damage occurs (working service limit), and no data is recorded if it does not occur;

[0028]

[0029] W i =N i ×m c gh (3)

[0030]

[0031] Where N sα N is the limit damage times for normal use. sβ W is the number of damages in service. i is the impact energy dissipation J, N i is the number of damages (i=1,2,…,n), m c is the mass of the falling weight kg, g is the free fall acceleration 9.8 m·s 2 , h is the drop height m, D is the impact toughness ratio, E is the ductility ratio, E is the impact energy ratio, α and β are the number of normal use limit damage and working service limit damage, respectively, c and d are the normal use limit damage and working service limit impact energy consumption, respectively;

[0032] The wear-impact composite test is performed according to the wear test steps and the impact test steps. Switching from the wear test to the impact test includes pulling up the lock to unlock the variable bayonet concentric locking device, swinging the handle to align the gear box with the main shaft to the non-working position, and aligning the drop hammer magnetic suction head to the working position. Switching from the impact test to the wear test includes removing the steel ball or hammer head, unlocking the locking rod adjustment scale to adjust the drop hammer magnetic suction head to the standard working height, pulling up the lock to unlock the variable bayonet concentric locking device, swinging the handle to align the gear box with the main shaft to the working position. After the test, record the concrete damage parameters of the single wear test and the single impact test, record the concrete damage parameters of the wear-impact composite damage test, compare the service environment design requirements, if the requirements are met, pass the concrete wear and impact design, if not, further optimize the concrete design, repeat the above test until the concrete meets the wear resistance and impact resistance requirements of the service environment design, and record the wear test data and the impact test data;

[0033] The recorded data is as follows:

[0034] After β cumulative impact damage or wear damage, a wear test is performed separately after impact damage until wear damage, and an impact test is performed separately after wear damage until impact damage. The residual properties of the specimen after a single damage are recorded:

[0035]

[0036] L i = l i-1 -l i (6)

[0037]

[0038] Where N i is the number of residual damages (i=1,2,…,n), N β is the number of damages in service, G i is the damage amount of the ith test kg / m 2 , L i The damage depth of the i-th test is m, L c is the damage depth m, e, f and g are the residual damage times, residual damage magnitude and residual damage depth respectively.

[0039] The application of the testing method of the road and bridge deck concrete wear and impact composite damage testing device comprises the following steps:

[0040] The wear-impact composite damage test is for urban roads and highways with a pavement thickness of 150-300mm, taking 200mm as a representative value, a damage depth of 5% as the normal use limit, and a damage depth of 10% as the working service limit, so the damage depths are 10mm and 20mm respectively; according to the recommended test block thickness of 50mm, the damage depths of 20% and 40% are set to correspond to the normal use limit damage depth of 10mm and the working service limit damage depth of 20mm, respectively.

[0041] ①Damage depth L c =l0-l i ≥20%×l0(normal use limit);

[0042] Damage depth L c =l0-l i ≥40%×l0(working service limit).

[0043] Where, L c is the damage depth m, l0 is the thickness of the specimen before the test m, l i is the thickness of the specimen after i tests, m,

[0044] ② The specimen is not damaged, that is, there is no through crack, and the test piece can still remain a whole (normal use limit);

[0045] The specimen is damaged, i.e. a through crack appears, causing the specimen to be unable to remain intact (working service limit).

[0046] Composite test: impact test first, then wear test, and repeat until any failure condition is met.

[0047] The outstanding advantages of the present invention are:

[0048] 1. The present invention can quantify the fatigue times of the concrete structure of the road bridge deck under the conditions of wear damage and impact damage, and quantitatively evaluate the wear damage, impact damage and wear-impact combined damage of the concrete of the road bridge deck.

[0049] 2. It overcomes the defect that traditional road and bridge deck concrete wear resistance and impact resistance testing equipment cannot perform wear and impact tests at the same time. The wear and impact damage state of the road and bridge deck concrete structure is characterized by the wear and impact composite damage testing device of the road and bridge deck concrete. It has important academic significance and engineering application value for the comprehensive evaluation and optimization of the wear and impact of concrete in multiple working conditions such as roads, bridges, and runways.

[0050] 3. This method is mature and stable, simple to operate, compact in structure, fast and efficient. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 It is an overall schematic diagram of the device of the present invention;

[0052] Figure 2 is a front view of the device of the present invention;

[0053] Figure 3 is a side view of the device of the present invention;

[0054] Figure 4 is a top view of the device of the present invention;

[0055] Figure 5 It is a schematic flow chart of the device testing method of the present invention.

[0056] Marked in the figure are: main body 1, test bench 2, concrete test block fixing fixture 2a, wear motor 3, column 4, gear box 5, variable bayonet concentric locking device 6, lock buckle 7, rotating handle 8, counterweight plate 9, main shaft 10, grinding head 11, telescopic sleeve 12, ruler 13, drop hammer magnetic suction head 14, rotary rod 15, concrete test block mold 16, vacuum cleaner 17, suction head 18, CNC box 19, steel ball 20, cover plate 21, small steel ball 22. DETAILED DESCRIPTION

[0057] The technical solution of the present invention is further described in detail below in conjunction with the accompanying drawings and implementation modes.

[0058] Example 1

[0059] like Figures 1 to 5 As shown, this embodiment is an example of the road and bridge deck concrete wear and impact composite damage testing device of the present invention, and the device includes a testing device body and testing device accessories.

[0060] The test device body includes a wear composite impact device body 1 and a test bench 2. The test bench 2 is provided with a concrete test block fixing fixture, including a fixture positioning calibration and a fixing knob. The rear of the main body 1 is a wear motor 3. The wear motor 3 transmits torque to the separated transmission shaft inside the column 4 through a transmission shaft installed inside the main body 1. The column 4 and the gear box 5 transmit torque to the gear set inside the gear box 5 through a detachable transmission shaft. The gear box 5 and the column 4 are connected by a variable bayonet concentric locking device 6. The variable bayonet concentric locking device 6 can be unlocked by pulling the lock buckle 7 upward. The gear box 5 can be rotated by rotating the handle 8. The test can be adjusted to use one or two counterweight plates 9 according to needs. The torque is transmitted from the gear box 5 to the main shaft 10, and the main shaft 10 drives the grinding head 11 to rotate. The grinding head 11 is equipped with a wear gear. The main shaft 10 is protected by a telescopic sleeve 12. The scale 13 can adjust the height of the drop hammer magnetic suction head 14. The height of the drop hammer magnetic suction head 14 can be fixed by tightening the locking rod 15.

[0061] The test device accessories include a test concrete block mold 16, the size of the concrete block mold 16 is a Φ150mm×50mm concrete mold, and the material can be steel or plastic; a vacuum cleaner 17 uses a suction head 18 to clean the debris or fragments of concrete peeling caused by wear or impact tests; a numerical control box 19 is connected to the device body 1 through a cable, and the digital display screen can display the current test items. The device can be started and stopped, and the test items and test methods can be switched through the buttons next to it; a steel ball 20 or a hammer with a mass of 4.5kg is used to impact the concrete block; a cover plate 21 is used to fix the impacted small steel ball 22 during the impact test, and the small steel ball 22 can transfer the load to the concrete block under the impact of the steel ball 20 and the drop hammer.

[0062] Example 2

[0063] This embodiment is an example of a test method applicable to the road bridge deck concrete wear and impact composite damage test device of the present invention. The road bridge deck concrete wear and impact composite damage test device is used to evaluate the durability and impact resistance of road bridge deck concrete under friction, wear and impact load composite damage, including the following steps:

[0064] (1) Test sample preparation: Design the concrete mix ratio and prepare concrete specimens using a Φ150 mm × 50 mm mold;

[0065] (2) Test equipment adjustment: select the wear test part or impact test part of the device according to the test needs. For composite damage tests, the test part can be switched during the test;

[0066] (3) Test parameter setting: Design test parameters according to test requirements and set test parameters in the CNC box. For the wear test part, you can input the number of grinding head rotations, the grinding head rotation time, or adjust the weight of the counterweight plate. For the impact test part, you can adjust the impact height (impact energy) and the number of impacts.

[0067] (4) Conduct a separate wear test: Place the test block on the test bench of the main body 1, fix the test block in the working position using the concrete test block fixing fixture 2, pull up the lock buckle 7 to unlock the variable bayonet concentric locking device 6, swing and rotate the handle 8 to make the gear box 5 drive the main shaft 10 to align with the working position, adjust the use of one or two counterweight plates 9 according to the test requirements, set the CNC box 19, press the test preparation button, the transmission shaft outputs the test preparation torque to make the main shaft 10 fall to the working position, the grinding head 11 with the worn gear contacts the surface of the test block, select the time test or the number of laps test according to the test requirements, press the button of the CNC box 19 to adjust the test time length or the number of test laps, press the start button to perform a wear test on the concrete test block, turn on the vacuum cleaner 17 and use the suction head 18 to clean the debris caused by wear and tear of the concrete without large fragments;

[0068] (5) Conducting a separate impact test: placing the test block on the test bench of the main body 1, placing the test block in the working position using the concrete test block fixing fixture 2, aligning the drop hammer magnetic suction head 14 with the working position, adjusting the height of the ruler 13 so that the drop hammer reaches the height required for the predetermined impact energy, tightening the locking rod 15 to fix the height of the drop hammer magnetic suction head 14, adsorbing the steel ball 20 or the hammer head on the drop hammer magnetic suction head 14, completing the drop hammer preparation, adjusting the knob of the concrete test block fixing fixture 2 so that the concrete fixture is located at the calibration position, completely fitting the cover plate 21 on the concrete test block fixing fixture, placing a small steel ball 22 in the middle hole, completing the concrete test block impact preparation, selecting single or multiple impacts according to the test requirements, pressing the button of the numerical control box 19 to start the impact test, after the single impact is completed, restoring the impact position of the small steel ball 22, installing the steel ball 20 or the hammer head back on the drop hammer magnetic suction head 14, and then conducting the impact test again;

[0069] (6) Carrying out a combined wear and impact test: The wear and impact test are tested according to the above steps. Switching from the wear test to the impact test includes pulling up the lock buckle 7 to unlock the variable bayonet concentric locking device 6, swinging the handle 8 to make the gear box 5 drive the main shaft 10 to align with the non-working position, and aligning the drop hammer magnetic suction head 14 to the working position; switching from the impact test to the wear test includes removing the steel ball 20 or the hammer head, unlocking the locking rotary rod 15 and adjusting the scale 13 to adjust the drop hammer magnetic suction head 14 to the standard working height. The working height is adjusted only when the working height of the drop hammer magnetic suction head 14 is lower than the standard working height, pulling up the lock buckle 7 to unlock the variable bayonet concentric locking device 6, swinging the handle 8 to make the gear box 5 drive the main shaft 10 to align with the working position; after the test, record the concrete damage parameters of the single wear test and the single impact test, and record the concrete damage parameters of the wear and impact combined damage test, and compare them with the service environment design requirements. If the requirements are met, the concrete wear and impact design is passed. If the requirements are not met, the concrete design is further optimized. Repeat the above test until the concrete meets the wear resistance and impact resistance requirements of the service environment design.

[0070] (7) Analysis of test results: Analyze the correlation between the surface wear depth, damage mass, impact cracks and deformation of the concrete specimens after damage, establish a wear-impact composite damage model for road and bridge deck concrete, and quantitatively evaluate the wear-impact composite damage resistance of road and bridge deck concrete.

[0071] Specific wear-impact composite damage test application examples:

[0072] Composite damage test steps:

[0073] (1) Pre-wear test: Use a counterweight plate to apply a load of 200N and pre-wear 30rad; brush the surface of the specimen clean and record the initial mass m0 and initial specimen thickness l0;

[0074] (2) i-th round of testing (i = 1, 2, ..., n)

[0075] 1) Impact test:

[0076] First record the specimen mass m1 and conduct a single impact test;

[0077] When the initial crack occurs (normal use limit), record the following data, if it does not occur, do not record;

[0078]

[0079] The following data are recorded when the damage occurs (working service limit), and no data is recorded if it does not occur;

[0080]

[0081] 3) Wear test:

[0082] Use the counterweight plate to apply a load of 200N and wear 60rad; brush the surface of the specimen clean and record the mass m2 and wear depth l of the specimen. i , calculate the damage amount G of the i-th test i With L i ;

[0083] Record the following data at the initial wear (normal use limit), and do not record if it does not appear;

[0084] <![CDATA[Cumulative wear times N cα > <![CDATA[Cumulative damage mass G cα > i＝α c

[0085] The following data are recorded when the damage occurs (working service limit), and no data is recorded if it does not occur;

[0086] <![CDATA[Cumulative wear times N cβ > <![CDATA[Cumulative damage mass G cβ > i＝β d

[0087] 4) Record the number of impact damage cycles N i

[0088] 5) Repeated impact test

[0089] 6) Repeated wear test

[0090] β) to impact damage or wear damage, after impact damage, wear test is performed separately until wear damage, after wear damage, impact test is performed separately until impact damage, and the residual properties of the specimen after single damage are recorded:

[0091]

[0092] The test example is as follows: It is known that concrete mix ratio x and concrete mix ratio y will be used in a certain highway road panel. It is now necessary to compare the wear and impact resistance of the two. The road and bridge deck concrete wear and impact composite damage test device and test method are used.

[0093] The following data were obtained through testing and recording:

[0094]

[0095] The following data are calculated:

[0096]

[0097]

[0098] Analysis of the anti-abrasion and impact performance of concrete x and concrete y: By comparing and analyzing the differences in the size of each data, the following results can be obtained: ① The advantages and disadvantages of the anti-abrasion and impact performance of concrete x and concrete y in the whole stage;

[0099] ② The impact resistance of concrete x and concrete y at the initial crack stage;

[0100] ③ The advantages and disadvantages of the wear resistance of concrete x and concrete y in the initial grinding stage;

[0101] ④ The impact resistance of concrete x and concrete y from the initial crack stage to the failure stage;

[0102] ⑤ The advantages and disadvantages of the wear resistance of concrete x and concrete y from the initial grinding stage to the destruction stage;

[0103] ⑥ The impact resistance or wear resistance of concrete a and concrete b after destruction.

[0104] By comparing the above situations, the anti-wear and impact performance of concrete a and concrete b is comprehensively analyzed and the best one is selected.

[0105] Application Example 1

[0106] C40 concrete with different mix ratios

[0107] Mix ratio per m 3 Amount of various concrete materials (kg)

[0108]

[0109] The following data were obtained through testing and recording:

[0110]

[0111] The following data are calculated:

[0112] C40x / C40y at first crack C40x / C40y at destruction D 1.59 1.62

[0113] C40x C40y E 0.26 0.24

[0114] Analysis of the anti-abrasion performance of concrete C40x and concrete C40y: By comparing and analyzing the differences in the size of each data, the following results can be obtained:

[0115] ① The abrasion resistance of the full-stage concrete C40x is better than that of concrete C40y;

[0116] ② The impact resistance of concrete C40x at the initial crack stage is better than that of concrete C40y;

[0117] ③ The wear resistance of concrete C40x in the initial grinding stage is better than that of concrete C40y;

[0118] ④ The impact resistance of C40x from the initial crack stage to the failure stage is better than that of concrete C40y;

[0119] ⑤ The impact resistance of C40x from the initial grinding stage to the destruction stage is better than that of concrete C40y;

[0120] ⑥ The impact resistance or wear resistance of concrete C40x and concrete C40y after destruction.

[0121]

[0122] C40x still has a certain residual wear resistance after impact damage, and C40y still has a certain residual impact resistance after wear damage.

[0123] Application Example 2

[0124] C30 concrete and C60 concrete

[0125] Mix ratio per m 3 Amount of various concrete materials (kg)

[0126]

[0127]

[0128] The following data were obtained through testing and recording:

[0129]

[0130] The following data are calculated:

[0131] Initial cracking time C60 / C30 Destruction time C60 / C30 D 5.40 3.84

[0132] x y E 0.52 0.90

[0133] Analysis of the anti-wear and impact performance of concrete C60 and concrete C30: By comparing and analyzing the differences in the size of each data, the following results can be obtained:

[0134] ① The abrasion resistance of the full-stage concrete C60 is better than that of the concrete C30;

[0135] ② The impact resistance of concrete C60 at the initial crack stage is better than that of concrete C30;

[0136] ③ The wear resistance of concrete C60 in the initial grinding stage is better than that of concrete C30;

[0137] ④ The impact resistance of C60 from the initial crack stage to the damage stage is better than that of concrete C30;

[0138] ⑤ The impact resistance of C60 from the initial grinding stage to the destruction stage is better than that of concrete C30;

[0139] ⑥ The impact resistance or wear resistance of concrete C60 and concrete C30 after destruction.

[0140]

[0141] C60 still has a certain residual impact resistance after wear and tear, while the residual performance of C30 after damage is 0.

[0142] Application Example 3

[0143] C80 concrete and ultra-high performance concrete

[0144] Mix ratio per m 3 Amount of various concrete materials (kg)

[0145]

[0146] The following data were obtained through testing and recording:

[0147]

[0148] The following data are calculated:

[0149] Initial cracking time C120 / C80 Destruction C120 / C80 D 1.24 1.26

[0150] C120 C80 E 0.52 0.49

[0151] Analysis of the anti-abrasion performance of ultra-high performance concrete and C80 concrete: By comparing and analyzing the differences in the size of each data, the following results can be obtained:

[0152] ① The anti-abrasion and impact performance of the full-stage ultra-high performance concrete is better than that of concrete C80;

[0153] ② The impact resistance of ultra-high performance concrete in the initial crack stage is better than that of concrete C80;

[0154] ③ The wear resistance of UHP concrete in the initial grinding stage is better than that of concrete C80;

[0155] ④ The impact resistance of ultra-high performance concrete from the initial crack stage to the destruction stage is better than that of concrete C80;

[0156] ⑤ The impact resistance of ultra-high performance concrete from the initial grinding stage to the destruction stage is better than that of concrete C80;

[0157] ⑥ The impact resistance or wear resistance of ultra-high performance concrete and concrete C80 after destruction.

[0158]

[0159] The residual impact resistance of ultra-high performance concrete after wear and tear is better than that of C80 concrete. The failure modes of ultra-high performance concrete and C80 concrete are both wear and tear.

Claims

1. A road and bridge deck concrete wear and impact composite damage testing device, characterized in that: The device includes a test device body and test device accessories. The test device body comprises a main body and a test bench, a concrete test block fixing fixture is arranged on the test bench, a wear motor is arranged behind the main body, the wear motor transmits torque to the detachable transmission shaft inside the column through a transmission shaft installed inside the main body, the column and the gear box transmit torque to the gear set inside the gear box through a detachable transmission shaft, the column and the gear box are connected through a variable bayonet concentric locking device, the variable bayonet concentric locking device can be unlocked by pulling the lock buckle upward, the gear box can be rotated by turning the handle, the counterweight plate is installed on the gear box and loaded on the main shaft, the torque is transmitted to the main shaft by the gear box, the main shaft drives the grinding head to rotate, a wear gear is installed on the grinding head, a telescopic sleeve is provided outside the main shaft for protection, the height of the drop hammer magnetic suction head is adjusted by a ruler, and the height of the drop hammer magnetic suction head can be fixed by tightening the locking rotary rod; The test device accessories include a concrete test block mold, a vacuum cleaner, a suction head, a CNC box, a steel ball, a cover plate and a steel ball. The vacuum cleaner uses the suction head to clean the debris or fragments of concrete peeling caused by wear or impact tests. The CNC box is connected to the main body through a cable. The digital display screen displays the current test items. The button start and stop device, the test items and the test mode are switched, and the steel ball or hammer impacts the concrete test block. The cover plate is used to fix the small steel ball to be impacted during the impact test. The small steel ball transfers the load to the concrete test block under the impact of the steel ball or the falling hammer.

2. The road and bridge deck concrete wear and impact composite damage testing device according to claim 1 is characterized in that: The concrete test block fixing fixture is composed of a fixture positioning mark and a fixing knob.

3. The road and bridge deck concrete wear and impact composite damage testing device according to claim 1 is characterized in that: The concrete test block mold has a size of Φ150mm×50mm and is made of steel or plastic.

4. The road and bridge deck concrete wear and impact composite damage testing device according to claim 1 is characterized in that: The mass of the steel ball is 4.5 kg.

5. A testing method applicable to the road and bridge deck concrete wear and impact composite damage testing device according to claim 1, characterized in that: The steps include: (1) Prepare concrete according to the mix ratio and pour it into the concrete test block mold; (2) Curing the test pieces to the specified age; (3) Conduct a single wear test, a single impact test, or a combined wear and impact test. The separate wear test is to place the test block on the main test bench, fix the test block in the working position with the concrete test block fixing fixture, pull up the lock buckle to unlock the variable bayonet concentric locking device, swing and rotate the handle to make the gear box drive the main shaft to align with the working position, adjust the use of one or two counterweight plates according to the test requirements, set the CNC box, press the test preparation button, the transmission shaft outputs the test preparation torque to make the main shaft fall to the working position, the grinding head with the worn gear contacts the surface of the test block, select the time test or the number of laps test according to the test requirements, press the CNC box button to adjust the test time length or the number of test laps, press the start button to perform a wear test on the concrete test block, turn on the vacuum cleaner and use the suction head to clean the debris caused by the wear of the concrete without large fragments, and record the data as follows: Record the following data at the initial wear (normal use limit), and do not record if it does not appear; The following data are recorded when the damage occurs (working service limit), and no data is recorded if it does not occur; Where N cα N is the limit damage times for normal use. cβ is the number of damages in service, G c The damage amount is kg / m 2 , G i is the damage amount of the ith test kg / m 2 , m1 is the mass of the specimen before the test (kg), m2 is the mass of the specimen after the test (kg), A is the damaged area of ​​the specimen (m 2 , α and β are the number of normal use limit damage and working service limit damage, a and b are the mass of normal use limit damage and working service limit damage, respectively; The single impact test is to place the test block on the main test bench, use the concrete test block fixing fixture to place the test block in the working position, align the drop hammer magnetic suction head with the working position, adjust the ruler height so that the drop hammer reaches the required height for the predetermined impact energy, tighten the locking rod to fix the height of the drop hammer magnetic suction head, adsorb the steel ball or hammer head on the drop hammer magnetic suction head, complete the drop hammer preparation, adjust the concrete test block fixing fixture knob so that the concrete fixture is located at the calibration position, completely fit the cover plate on the concrete test block fixing fixture, put a small steel ball in the middle hole, complete the concrete test block impact preparation, select single or multiple impacts according to the test requirements, press the CNC box button to start the impact test, after the single impact is completed, restore the small steel ball impact position, install the steel ball or hammer head back on the drop hammer magnetic suction head, and then perform the impact test again. The recorded data is as follows: When the initial crack occurs (normal use limit), record the following data, if it does not occur, do not record; The following data are recorded when the damage occurs (working service limit), and no data is recorded if it does not occur; <h2 style=";text-align:left;direction:ltr">W<h2 style=";text-align:left;direction:ltr"> i <h2 style=";text-align:left;direction:ltr"> =N<h2 style=";text-align:left;direction:ltr"> i <h2 style=";text-align:left;direction:ltr"> ×m<h2 style=";text-align:left;direction:ltr"> c <h2 style=";text-align:left;direction:ltr"> gh (3) Where N sα N is the limit damage times for normal use. sβ W is the number of damages in service. i is the impact energy dissipation J, N i is the number of damages (i=1,2,…,n), m c is the mass of the falling weight kg, g is the free fall acceleration 9.8 m·s 2 , h is the drop height m, D is the impact toughness ratio, E is the ductility ratio, E is the impact energy ratio, α and β are the number of normal use limit damage and working service limit damage, respectively, c and d are the normal use limit damage and working service limit impact energy consumption, respectively; The wear-impact composite test is performed according to the wear test steps and the impact test steps. Switching from the wear test to the impact test includes pulling up the lock to unlock the variable bayonet concentric locking device, swinging the handle to align the gear box with the main shaft to the non-working position, and aligning the drop hammer magnetic suction head to the working position. Switching from the impact test to the wear test includes removing the steel ball or hammer head, unlocking the locking rod adjustment scale to adjust the drop hammer magnetic suction head to the standard working height, pulling up the lock to unlock the variable bayonet concentric locking device, swinging the handle to align the gear box with the main shaft to the working position. After the test, record the concrete damage parameters of the single wear test and the single impact test, record the concrete damage parameters of the wear-impact composite damage test, compare the service environment design requirements, if the requirements are met, pass the concrete wear and impact design, if not, further optimize the concrete design, repeat the above test until the concrete meets the wear resistance and impact resistance requirements of the service environment design, and record the wear test data and the impact test data; The recorded data is as follows: After β cumulative impact damage or wear damage, a wear test is performed separately after impact damage until wear damage, and an impact test is performed separately after wear damage until impact damage. The residual properties of the specimen after a single damage are recorded: L i ＝l i-1 -l i (6) Where N i is the number of residual damages (i=1,2,…,n), N β is the number of damages in service, G i is the damage amount of the ith test kg / m 2 , L i The damage depth of the i-th test is m, L c is the damage depth m, e, f and g are the residual damage times, residual damage magnitude and residual damage depth respectively.

6. Application of the testing method of the road and bridge deck concrete wear and impact composite damage testing device according to claim 5, characterized in that: The steps include: The wear-impact composite damage test is for urban roads and highways with a pavement thickness of 150-300mm, taking 200mm as a representative value, a damage depth of 5% as the normal use limit, and a damage depth of 10% as the working service limit, so the damage depths are 10mm and 20mm respectively; according to the recommended test block thickness of 50mm, the damage depths of 20% and 40% are set to correspond to the normal use limit damage depth of 10mm and the working service limit damage depth of 20mm, respectively. ①Wound depth L c =l0-l i ≥20%×l0(normal use limit); Damage depth L c =l0-l i ≥40%×l0(working service limit); Where, L c is the damage depth m, l0 is the thickness of the specimen before the test m, l i is the thickness of the specimen after i tests, m, ② The specimen is not damaged, that is, there is no through crack, and the test piece can still remain a whole (normal use limit); The specimen is damaged, i.e. a through crack appears, causing the specimen to be unable to remain intact (working service limit). Composite test: impact test first, then wear test, and repeat until any failure condition is met.

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