CN107560937B - Clamp and method for testing anti-shearing performance of road joint sealing adhesive - Google Patents

Abstract

The invention provides a test fixture and a test method for the shear resistance performance of road seam filling glue, belonging to the technical field of traffic roads, in particular to a test fixture and a test method for the shear resistance performance of road seam filling glue. The test fixture of the present invention includes a clamping tension component and a forming component; the specific process of the test method is as follows: step 1, making several asphalt concrete test blocks; step 2, making several test pieces; step 3, making several groups of test pieces shear, and obtain the shear displacement curve of the joint glue; step 4, calculate the failure strain ε and failure shear stress τ; step 5, according to the failure strain ε and failure shear stress τ, carry out the shear resistance performance of the joint glue Evaluation. The invention solves the problem that the prior art cannot effectively evaluate the shear resistance performance of the road joint filling glue, which leads to the insufficiency of the road maintenance department in analyzing the failure mechanism of the joint filling glue. The invention can be applied to the performance test of the joint-filling glue.

Description

A test fixture and test method for shear resistance performance of road joint filling glue

technical field

The invention belongs to the technical field of traffic roads, and particularly relates to a test fixture and a test method for the shear resistance performance of road joint-filling glue.

Background technique

Cracks are one of the most common pavement diseases. At present, the method to deal with pavement cracks is usually grouting. As a common grouting material, road joint grouting glue is widely used by maintenance departments. The road joint filling glue should have good low temperature deformation ability. The test method for the low temperature deformation performance of road joint filling glue is mainly tensile test. Previously, after literature retrieval, the invention patent with the patent number of 201310133624.6 provides a low temperature joint filling material. Loading device for performance testing. However, the road joint glue will be subjected to the comprehensive shearing action of temperature stress and wheel load during the service process. The road joint glue is made of modified asphalt polymer materials, usually made of asphalt, rubber and other modifiers. There are obvious differences in the shear resistance and tensile properties of the material, and the traditional tensile test cannot effectively evaluate the shear resistance of the road joint glue, which leads to the lack of road maintenance departments in analyzing the failure mechanism of the joint glue. Therefore, it is necessary to develop a shearing jig for road joint caulk and propose a new method for testing the shear resistance of road joint grouting based on this jig.

SUMMARY OF THE INVENTION

In order to solve the problem that the prior art cannot effectively evaluate the shear resistance performance of the road joint filling glue, which leads to the insufficiency of the road maintenance department in analyzing the failure mechanism of the joint filling glue, the invention provides a test for the shear resistance performance of the road joint filling glue. Fixtures and test methods.

The test fixture for the shear resistance performance of road seam filling glue according to the present invention comprises a clamping and stretching component and a forming component;

The clamping and stretching assembly includes two oppositely arranged clamping arms, each clamping arm includes a bottom plate and a side plate vertically fixed to the bottom plate; one of the bottom plate is provided with a limiting groove inside, and the other bottom plate is provided inside a limit protrusion, the limit groove and the limit protrusion are matched with each other; the side plate extends inward with a sample groove;

The forming assembly includes a spacer block and two limit blocks, the two limit blocks are symmetrically arranged on the spacer block, and the inner sides of the two limit blocks and the spacer block form a rectangular hole groove; the spacer block is connected to the two spacer blocks. The width of the limit block is equal;

The height of the sample slot is equal to the sum of the height of the rectangular hole slot and twice the height of the spacer, and the distance between the two sides of the sample slot is greater than the distance between the two sides of the rectangular hole slot;

When the clamping and stretching assemblies are closed, that is, when the limiting groove and the limiting protrusion are sleeved, the two sample grooves are aligned, and the distance between the two sample grooves is equal to the distance between the two sample grooves. width.

The method for testing the shear resistance of road joint filling glue according to the present invention is realized by the following technical solutions:

Step 1, make several asphalt concrete test blocks: select asphalt concrete blocks according to the gradation of surface layer materials in the actual pavement structure, and use a cutting machine to cut the selected asphalt concrete blocks into asphalt concrete test blocks with the same size as the sample groove;

Step 2, making a number of test pieces composed of asphalt concrete test blocks and joint-filling rubber blocks;

Step 3. Perform shearing of several groups of specimens to obtain the shear displacement curve of the joint-filling glue;

The specific process of specimen shearing is as follows:

Step 31: Install the clamping and stretching assembly in the loading device for the low-temperature performance test of the joint filling material, so that the limiting protrusion is sleeved with the limiting groove;

Step 32: Install the prepared specimen in the sample tank;

Step 33: Keep the heat preservation at the specified test temperature for more than or equal to 4h;

Step 34: Connect the loading device, and set the loading rate and loading range;

Step 35: Shear the specimen to obtain the shear displacement curve of the seam-filling glue;

Step 4: Calculate the failure strain ε and the failure shear stress τ;

Step 5: Evaluate the shear resistance of the joint-filling adhesive according to the failure strain ε and the failure shear stress τ.

The most prominent feature and significant beneficial effect of the present invention are:

Through the shear resistance test tests carried out on three kinds of joint glues by the present invention at a temperature of -15°C and a loading rate of 100mm/h, it can be seen that the present invention has the following advantages:

(1), use the road joint-filling glue shear resistance test fixture and the test method proposed by the present invention to measure the road joint-filling glue shear resistance performance, by transforming the existing equipment, to obtain the shear failure interface using the loading device The purpose of the shear displacement curve;

(2) The test method is simple and easy to understand, and the clamping and stretching components and forming components can be used repeatedly up to 1 million times;

(3) The length of the test piece can be changed by adjusting the distance of the limit block of the forming assembly;

(4) The test piece simulates the service environment of the seam filling glue (the actual pavement structure environment), which is scientific and reasonable. The shear resistance of 99% of the seam filling glue in the actual engineering road can be evaluated by the present invention.

Description of drawings

FIG. 1 is a schematic structural diagram of the clamping and stretching assembly according to the present invention;

FIG. 2 is a schematic structural diagram of the molding assembly of the present invention;

Fig. 3 is the schematic diagram of the sample molding of the present invention;

Fig. 4 is the schematic diagram of the test piece of the present invention;

5 is a schematic diagram of the assembly and loading of the clamping tension assembly and the test piece according to the present invention;

Fig. 6 is the failure strain and failure shear stress curve diagram of the test piece in the embodiment of the present invention;

Fig. 7 is the schematic diagram of the loading device of the present invention;

Among them, 21. Clamping and tensile assembly, 22. Forming assembly, 23. Asphalt concrete test block, 24. Test piece, 25. Joint glue, 21-1. Sample groove, 21-2. Limit protrusion, 21-3. Limit groove, 21-4. Bottom plate, 21-5. Side plate, 22-1. Spacer block, 22-2. Limit block, 22-3 Rectangular hole groove.

Detailed ways

Embodiment 1: This embodiment will be described with reference to FIG. 1 and FIG. 2 . A test fixture for the shear resistance of road joint filling glue provided in this embodiment includes a clamping and stretching assembly 21 and a forming assembly 22;

As shown in FIG. 1 , the clamping and stretching assembly 21 includes two oppositely arranged clamping arms, each clamping arm includes a bottom plate 21-4 and a side plate 21-5 vertically fixed to the bottom plate; one of them The inner side of the bottom plate 21-4 is provided with a limiting groove 21-3, and the inner side of the other bottom plate is provided with a limiting protrusion 21-2, and the limiting groove 21-3 and the limiting protrusion 21-2 are matched with each other; The side plate 21-5 extends inwardly to form a rectangular sample slot 21-1; the inner side here refers to the opposite side of the two clamping arms.

As shown in FIG. 2 , the forming assembly 22 includes a spacer block 22-1 and two limit blocks 22-2. The two limit blocks 22-2 are symmetrically arranged on the spacer block 22-1. The inner side of the block 22-2 and the spacer block 22-1 form a rectangular hole groove 22-3; the spacer block 22-1 and the two limit blocks 22-2 have the same width;

The height of the sample slot 21-1 is equal to the sum of the height of the rectangular hole slot 22-3 and twice the height (ie thickness) of the spacer 22-1, and the distance between the two sides of the sample slot 21-1 is greater than that of the rectangular hole slot 22-3 The distance between the two sides; in this way, the contact surface of the joint glue block 25 in the middle of the test piece 24 made by the molding assembly 22 and the asphalt concrete test block 23 is located in the middle of the side surface of the asphalt concrete test block 23, and the joint glue Compared with the asphalt concrete test block 23, the upper and lower surfaces of the block 25 are both retracted by a distance equivalent to the thickness of the pad block 22-1;

When the clamping and stretching assembly 21 is closed, that is, when the limiting groove 21-3 is sleeved with the limiting protrusion 21-2, the two sample grooves 21-1 are aligned, and the two sample grooves 21-1 are aligned. The distance between 21-1 is equal to the width of the spacer 22-1.

Embodiment 2: The difference between this embodiment and Embodiment 1 is that the width of the spacer block 22-1 and the two limiting blocks 22-2 are both 12 mm.

Other steps and parameters are the same as in the first embodiment.

Embodiment 3: The difference between this embodiment and Embodiment 2 is that when the clamping and stretching assembly 21 is closed and the limiting groove 21-3 is sleeved with the limiting protrusion 21-2, A gap is left between the two sample grooves 21-1, and the distance between the two sample grooves 21-1 is 12 mm.

Other steps and parameters are the same as in the second embodiment.

Embodiment 4: The difference between this embodiment and Embodiment 2 is that the height of the spacer 22-1 is preferably 3-7 mm.

Embodiment 5: The difference between this embodiment and the second embodiment is that the height of the rectangular hole 22-3 formed by the inner side surfaces of the two limiting blocks 22-2 and the spacer block 22-1 is 20 mm.

Other steps and parameters are the same as in the second embodiment.

Embodiment 6: The difference between this embodiment and Embodiment 1 is that the material of the clamping and stretching assembly 21 is preferably a rigid material with a relatively high stubbornness.

Other steps and parameters are the same as in the first embodiment.

Embodiment 7: This embodiment will be described with reference to Fig. 2, Fig. 3, Fig. 4, Fig. 5 and Fig. 7. This embodiment provides a method for testing the shear resistance of road joint filling glue. The testing method is specific Include the following steps:

Step 1. Make several asphalt concrete test blocks 23: Select asphalt concrete blocks according to the gradation of surface layer materials in the actual pavement structure, and use a cutting machine to cut the selected asphalt concrete blocks into asphalt concrete test blocks of the same size as the sample groove 21-1. block 23;

Step 2, as shown in FIG. 3, make a test piece 24 composed of several asphalt concrete test blocks 23 and joint-filling rubber blocks 25, as shown in FIG. 4 is a schematic structural diagram of the test piece 24;

Step 3: As shown in Figure 5, shear several groups of test pieces 24 to obtain the shear displacement curve of the joint-filling glue;

The specific process of shearing the specimen 24 is as follows:

Step 31. Install the clamping and stretching assembly 21 in the loading device for the low temperature performance test of the joint filling material, so that the limiting protrusion 21-2 is sleeved with the limiting groove 21-3; this embodiment adopts the patented The invention patent No. 201310133624.6 provides a loading device for low-temperature performance testing of seam filling materials, as shown in Figure 7, the loading device includes an oil tank 1, a bearing plate, a transmission unit, a support sliding unit and a loading unit;

The transmission unit includes a motor 3, a reducer 4, a first bevel gear 5, a second bevel gear 6, a transmission shaft 7, a fixed frame 8 and a transmission member 9;

The supporting sliding unit includes a sliding rail 10, a sliding plate 11, a connecting assembly 12 and a transition plate 13;

The loading unit includes a pressure sensor 16, a mobile loading platform 14, a fixed loading platform 19 and two sets of fixtures 15;

The fixing frame 8 is installed on the bearing plate 2 arranged on the bottom end surface of the oil tank 1, the bearing plate 2 is installed with the slide rail 10, the slide plate 11 is installed on the slide rail 10, and the slide plate 11 can slide on the slide rail 10, moving the loading The platform 14 is used to install one end of the test piece 18, and the fixed loading platform 19 is used to install the other end of the test piece 18;

The fixed loading platform 19 is connected with the fixed frame 8, the mobile loading platform 14 is connected with the sliding plate 11 through the connecting assembly 12, a set of fixtures 15 is installed on each of the fixed loading platform 19 and the mobile loading platform 14, and the two sets of fixtures 15 are arranged opposite to each other. , each set of fixtures 15 includes a movable plate 15-1, a fixed plate 15-2, a wrench 15-3, a column 15-4, four coil springs 15-5 and four top columns 15-6, each set of fixtures The movable plate 15-1 and the fixed plate 15-2 in 15 are arranged side by side. There are four top posts 15-6 passing through between the movable plate 15-1 and the fixed plate 15-2. The plate 15-1 is fixedly connected, the four top columns 15-6 can slide on the fixed plate 15-2, and the end of each top column 15-6 adjacent to the specimen on the mobile loading platform 14 is provided with a protrusion 15 -7, the end of each top column 15-6 adjacent to the test piece on the fixed loading platform 19 is provided with a protrusion 15-7, the top column located between the protrusion 15-7 and the fixed plate 15-2 15-6 is sleeved with a coil spring 15-5, one end of the wrench 15-3 is rotatably connected with the mobile loading platform 14 connected with the sliding plate 11, and a wrench is arranged between the fixed plate 15-2 and the movable plate 15-1. 15-3 is connected to the cylinder 15-4, the rotation of the wrench 15-3 can drive the cylinder 15-4 to rotate, and the rotation of the cylinder 15-4 can drive the movable plate 15-1 to reciprocate horizontally;

The output shaft of the motor 3 is arranged vertically, the output end of the motor 3 is connected with the input end of the reducer 4, the output end of the reducer 4 is installed with the first bevel gear 5, the second bevel gear 6 is installed on the transmission shaft 7, and the first bevel gear 5 is installed on the output end of the reducer 4. A bevel gear 5 meshes with the second bevel gear 6, the transmission shaft 7 is rotatably connected to the fixing frame 8, one end of the transmission shaft 7 is threaded, and the transmission member 9 is installed on one end of the transmission shaft 7 and the two are threadedly connected. A pressure sensor 16 is installed at the end, a transition plate 13 is connected to the lower end surface of the mobile loading platform 14 between the pressure sensor 16 and the connecting assembly 12 , and the sensing end of the pressure sensor 16 points to the transition plate 13 .

Step 32: Install the prepared test piece 24 in the sample tank 21-1, so that the asphalt concrete test block 23 matches the sample tank 21-1;

Step 33: Keep the heat preservation at the specified test temperature for more than or equal to 4h;

Step 34: Connect the loading device, and set the loading rate and loading range;

Step 35: Shear the test piece 24 to obtain the shear displacement curve of the seam-filling glue; the loading device applies a reverse force to the two bottom plates 21-4 to force the two clamps that clamp the tension assembly 21. The arms are separated, resulting in shear damage at the joint-filling rubber block 25 of the specimen 24;

Step 4: Calculate the failure strain ε and the failure shear stress τ;

Step five, according to the failure strain ε and failure shear stress τ to evaluate the shear resistance of the joint-filling adhesive:

The failure strain and failure shear stress of several groups of specimens 24 can be obtained, and the average value can be obtained, and then the shear resistance performance of the joint potting compound can be evaluated according to the failure strain ε and failure shear stress τ, or according to the failure strain ε and failure The shear stress τ is obtained from the failure strain and failure shear stress curve, and the shear resistance of the joint potting compound is evaluated.

Embodiment 8: The difference between this embodiment and Embodiment 7 is that the specific process of making the test piece composed of the asphalt concrete test block 23 and the joint-filling rubber block 25 described in step 2 is as follows:

Step 21: As shown in Figure 2, evenly brush the release agent in the rectangular hole groove 22-3, and place two asphalt concrete test blocks 23 made in step 1 symmetrically on both sides of the rectangular hole groove 22-3, The limit blocks 22-2 are in contact, and the distance between the limit blocks 22-2 is adjusted so that the distance between the two sides of the rectangular hole groove 22-3 is smaller than the length of the asphalt concrete test block 23; the adjustment of the limit blocks 22- After the distance between 22-3, the spacer can also be brushed on the bottom surface of the rectangular hole groove 22-3.

Step 22: Slowly pour the fluidized joint glue into the rectangular hole groove 22-3 until the rectangular space enclosed by the asphalt concrete test block 23 and the molding assembly 22 is filled. When air bubbles are generated, the surface of the glue for the joint filling should be slightly higher than the surface of the groove 22-3 of the rectangular hole, and then it is cooled at a temperature of 20°C to 25°C for more than or equal to 2 hours. The asphalt concrete test block 23 is consolidated;

Step 23: Use a hot scraper to scrape off the joint glue on the top surface beyond the notch surface of the rectangular hole groove 22-3, and take out the two limit blocks 22-2 and the spacer block 22-1 to obtain an asphalt concrete test block 23 24 test pieces composed of 25 joint glue blocks.

Other steps and parameters are the same as in the seventh embodiment.

Specific embodiment 9: The difference between this embodiment and the specific embodiment 8 is that the calculation method of the failure strain ε and the failure shear stress τ described in step 4 is:

Wherein: ε represents the failure strain; l represents the length of the joint-filling rubber block 25 in the middle of the specimen 24 at failure, which is read by the data acquisition system of the loading device; _l0 represents the original length of the joint-filling rubber block 25 in the middle of the test piece 24 (that is, the distance between the two sides of the rectangular hole 22-3); τ represents the failure shear stress; F represents the failure tensile force, which is read by the data acquisition system of the loading device, and A represents the shear area of the test piece 24, that is, the The contact area between the joint block 25 and the asphalt concrete test block 23 .

Other steps and parameters are the same as in the ninth embodiment.

Embodiment 10: This embodiment differs from Embodiment 9 in that the number of groups for shearing the specimen 24 in the third step is 3 to 5 groups.

Other steps and parameters are the same as in the ninth embodiment.

Example

Adopt the following examples to verify the beneficial effects of the present invention:

First, a test fixture for the shear resistance of road joint-filling glue is made, including a clamping and stretching assembly 21 and a forming assembly 22; the clamping and stretching assembly 21 is made of stainless steel, and the size of the sample groove 21-1 is 40mm×30mm× 30mm (wherein, the distance between the two sides of the sample groove 21-1 is 40mm); the spacer block 22-1 is 12mm wide and 5mm high, and the inner sides of the two limit blocks 22-2 and the spacer block 22-1 form a rectangle The hole groove 22-3; the width of the spacer block 22-1 and the two limit blocks 22-2 are both 12mm; the inner side surface of the two limit blocks 22-2 and the spacer block 22-1 form a size of 1 ₀ × 20mm×12mm rectangular hole slot 22-3.

The specific process of the test is:

Step 1. Make 18 asphalt concrete test blocks 23: Select asphalt concrete blocks according to the gradation of surface layer materials in the actual pavement structure, and use a cutting machine to cut the selected asphalt concrete blocks into asphalt concrete with the same size as the sample groove 21-1. Test block 23;

Step 2, use B joint glue, C joint glue, D joint glue to make 3 pieces (a total of 9 pieces) of asphalt concrete test block 23 and joint glue block 25 respectively to make test pieces 24; The specific method is:

Step 21. Evenly brush the release agent in the rectangular hole groove 22-3, and place two asphalt concrete test blocks 23 produced in step 1 symmetrically on both sides of the rectangular hole groove 22-3, and connect with the limit block 22. -2 close, adjust the distance between the limit blocks 22-2, so that the length of the rectangular hole groove 22-3 is smaller than the length of the asphalt concrete test block 23;

Step 22: Slowly pour the fluidized joint glue into the rectangular hole groove 22-3 until the rectangular space enclosed by the asphalt concrete test block 23 and the molding assembly 22 is filled, and then the temperature is 20°C to 25°C. After cooling for 2 hours at the temperature, the joint filling glue solidifies into joint filling glue block 25;

Step 23: Take out the two limit blocks 22-2 and the cushion block 22-1 to obtain a test piece 24 composed of an asphalt concrete test block 23 and a joint-filling rubber block 25.

Step 3: The shearing of three groups of specimens 24 is performed on the B joint glue, the C joint glue, and the D joint glue, respectively, and the shear displacement curve of the joint glue is obtained;

The specific process of shearing the specimen 24 is as follows:

Step 31. Install the clamping and stretching assembly 21 in the loading device, so that the limiting protrusion 21-2 is sleeved with the limiting groove 21-3;

Step 32: Install the prepared sample 24 in the sample tank 21-1;

Step 33: Incubate at -15°C for 4h;

Step 34: Connect the loading device, set the loading rate to 100mm/h, and the loading range;

Step 35: Shear the test piece 24 to obtain the shear displacement curve of the joint-filling glue;

Step 4. Calculate the failure strain ε and the failure shear stress τ:

Step 5: Obtain the failure strain and failure shear stress of 3 groups of specimens 24 for each type of joint glue, and take the average value, and finally obtain the failure strain and failure shear stress curve as shown in Figure 6, which is used for evaluation. The shear resistance of the joint glue, and it can be concluded that the C joint glue is better than the D joint glue, and the D joint glue is better than the B joint glue.

The present invention can also have other various embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art can make various corresponding changes and deformations according to the present invention, but these corresponding changes and deformations are all It should belong to the protection scope of the appended claims of the present invention.

Claims (3)

1. A road joint-filling adhesive shear resistance test fixture is characterized in that, comprising clamping and stretching assembly (21) and forming assembly (22); The clamping and stretching assembly (21) includes two clamping arms arranged opposite to each other, and each clamping arm includes a bottom plate (21-4) and a side plate (21-5) vertically fixed on the bottom plate; The inner side of the bottom plate (21-4) is provided with a limiting groove (21-3), and the inner side of the other bottom plate is provided with a limiting protrusion (21-2), the limiting groove (21-3) and the limiting protrusion The tops (21-2) are matched with each other; the side plates (21-5) are extended inwardly to form a sample groove (21-1); The forming assembly (22) includes a spacer (22-1) and two limit blocks (22-2), and the two limit blocks (22-2) are symmetrically arranged on the spacer (22-1) , the inner sides of the two limit blocks (22-2) and the spacer block (22-1) form a rectangular hole groove (22-3); the spacer block (22-1) and the two limit blocks (22-2) ) are equal in width; The height of the sample slot (21-1) is equal to the sum of the height of the rectangular hole slot (22-3) and twice the height of the spacer (22-1), and the distance between the two sides of the sample slot (21-1) greater than the distance between the two sides of the rectangular hole slot (22-3); When the clamping and stretching assembly (21) is closed, that is, when the limiting groove (21-3) is sleeved with the limiting protrusion (21-2), the two sample grooves (21-1) ) are aligned, and the distance between the two sample slots (21-1) is equal to the width of the spacer (22-1); The width of the spacer block (22-1) and the two limit blocks (22-2) are both 12mm. When the clamping and stretching assembly (21) is closed, the gap between the two sample slots (21-1) is The distance is 12mm; The height of the rectangular hole groove (22-3) formed by the inner side surfaces of the two limiting blocks (22-2) and the spacer block (22-1) is 20 mm. 2 . The shear resistance test fixture for road joint filling glue according to claim 1 , wherein the height of the spacer ( 22 - 1 ) is 3-7 mm. 3 . 3 . The shear resistance test fixture for road joint-filling glue according to claim 1 , wherein the clamping and stretching assembly ( 21 ) is made of a steel material. 4 .

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