Transverse constraint stretching device for calibrating elongation of geotechnical cloth

Abstract

A transverse constraint stretching device for calibrating the elongation of geotechnical cloth comprises a clamping device and a fixing device, and the clamping device comprises an upper clamping device, a lower clamping device and a sliding rod; the fixing device comprises a sliding block, a needle plate and an ejector rod; the needle plate and the ejector rod are fixed on the sliding block; the sliding rod is fixed with the lower clamping device, the fixing device and the upper clamping device sequentially penetrate through the sliding rod and the sliding block and are uniformly distributed between the upper clamping device and the lower clamping device, and the upper clamping device and the lower clamping device are symmetrically arranged on the universal testing machine up and down. The upper side and the lower side of the geotechnical cloth are fixed to the upper clamping device and the lower clamping device respectively, and the left side and the right side of the geotechnical cloth are fixed to the needle plates of the fixing devices respectively. According to the utility model, the geotextile can be transversely restrained to prevent necking, and meanwhile, the extension change of the geotextile after being stretched can be accurately reflected by calibrating the distance between the two ejector rods, so that more accurate mechanical properties are obtained, and the production process of the geotextile is effectively guided.

Description

Technical Field

[0001] The utility model belongs to the research field of mechanical properties of geotextiles, and specifically designs a transverse restraint stretching device for calibrating the elongation of geotextiles. Background Art

[0002] As a material for treating reflective cracks in pavement, geotextiles are increasingly used in engineering construction, and research on the mechanical properties of geotextiles is increasing. However, during the study of the tensile mechanics of geotextiles, lateral necking will occur, affecting the accuracy of the experiment.

[0003] Prior art, such as utility model patent CN 215525306 U, discloses a side-limited tensile clamp that can achieve unidirectional in-plane elongation and deformation of geotextiles while simultaneously limiting lateral displacement. However, this prior art suffers from the following drawbacks: the number of sliding blocks on the left and right sliding rods cannot be freely changed, and during stretching, the left and right sliding blocks cannot be guaranteed to remain on the same horizontal line. Furthermore, when clamping a sample with a quick clamp, the clamping force is often less than the lateral contraction force, causing the sample to slip on either side. Summary of the Invention

[0004] The purpose of the utility model is to overcome the existing problems and provide a geotextile lateral constraint stretching device for calibrating elongation changes. The left and right sides of the geotextile can be directly pressed on the needle plate to realize the lateral constraint of the geotextile, and the elongation change of the geotextile after stretching can be calibrated by measuring the distance between the two push rods.

[0005] The technical solution adopted in this utility model is:

[0006] A transverse restraint stretching device for calibrating the elongation of geotextiles includes a clamping device and several fixing devices; the clamping device includes an upper clamping device, a lower clamping device, and a sliding rod; each fixing device includes a sliding block, a needle plate, and a push rod; the needle plate and the push rod are both fixed on the sliding block; the sliding rod is fixed to the lower clamping device, the fixing device and the upper clamping device pass through the sliding rod in sequence, the sliding blocks are evenly distributed between the upper clamping device and the lower clamping device, the upper clamping device and the lower clamping device are symmetrically installed on a universal testing machine, the upper and lower sides of the geotextile are respectively fixed to the upper clamping device and the lower clamping device, and the left and right sides of the geotextile are respectively fixed to the needle plates of the fixing devices.

[0007] Preferably, six holes are evenly distributed on the clamping surfaces of the upper clamping device and the lower holding device of the utility model; the clamping surfaces of the upper clamping device and the lower clamping device are both wavy, which are used to increase the force-bearing area of ​​the geotextile and reduce the slippage of the sample.

[0008] Preferably, rolling steel balls are embedded in the sliding block of the present invention to reduce friction between the sliding block and the sliding rod.

[0009] Preferably, the number of the fixing devices of the present invention can be freely adjusted as needed.

[0010] Preferably, the utility model can fix the left and right sides of the geotextile through the needle plate of the fixing device, so that the geotextile will not neck during the stretching process. As the geotextile is stretched, the fixing device slides on the slide rod along the stretching direction of the geotextile through the steel balls inside the sliding block.

[0011] The upper side of the geotextile of the utility model is fixed in the upper clamping device, and the lower side of the geotextile is fixed in the lower clamping device. The top of the upper clamping device and the bottom center of the lower clamping device are both provided with connecting rods. The upper clamping device and the lower clamping device are respectively fixed to the upper end and the lower end of the universal testing machine through their respective connecting rods. The universal testing machine is also connected to a computer and a video extensometer.

[0012] The utility model provides a lateral constraint stretching device for calibrating the elongation of geotextiles, which can directly press the geotextiles on the needle plate of the fixing device to realize the lateral constraint of the geotextiles, and can obtain the precise elongation change of the geotextiles after stretching by calibrating the distance between the two top rods, thereby improving the accuracy of the mechanical performance parameters of the geotextiles.

[0013] The present invention adopts the above technical solution, which has the following beneficial effects compared with the prior art:

[0014] The utility model fixes the two sides of the geotextile through the needle plate of the fixing device to reduce the necking during unidirectional stretching and the left and right sides slipping of the sample caused by excessive necking force, and can calibrate the elongation change of the geotextile after stretching by measuring the distance change between the two top rods. At the same time, the sliding block of the fixing device is embedded with a rollable steel ball, which can reduce the friction between the sliding block and the sliding rod, reduce the experimental errors caused by various factors, obtain more accurate experimental data, and effectively guide the production process of the geotextile.

[0015] The utility model also relates to a method for performing transverse constrained stretching on a geotextile using the above-mentioned stretching device, which can reduce the experimental error caused by the necking of the geotextile during stretching. At the same time, the device can accurately reflect the elongation change of the geotextile after stretching by measuring the change in the distance between the two push rods. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 Schematic diagram of the transverse restraint tensile device used to calibrate the elongation of geotextiles.

[0017] Figure 2 A schematic diagram of the structure of the fixing device.

[0018] In the figure, 1-upper clamping device, 2-lower clamping device, 3-sliding block, 4-sliding rod, 5-needle plate, 6-top rod, 7-upper connecting rod, 8-lower connecting rod, 9-bolt, 10-steel ball. DETAILED DESCRIPTION

[0019] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.

[0020] The utility model provides a transverse restraint stretching device for calibrating the elongation of a geotextile.

[0021] In this embodiment, referring to Figure 1-2 The device includes a clamping device and a fixing device, the clamping device includes an upper clamping device 1 and a lower clamping device 2, the fixing device includes a sliding block 3, a needle plate 5 and a push rod 6; the sliding rod 4 is fixed to the lower clamping device 2, the fixing device and the upper clamping device 1 pass through the sliding rod 4 in turn, the sliding block 3 is evenly distributed between the upper clamping device and the lower clamping device, the upper clamping device 1 and the lower clamping device 2 are symmetrically installed on the universal testing machine, the universal testing machine is not drawn in the figure, the upper and lower sides of the geotextile are respectively fixed to the upper clamping device 1 and the lower clamping device 2, and the left and right sides of the geotextile are respectively fixed to the needle plate 5 of the fixing device.

[0022] like Figure 1 As shown, the upper clamping device 1 and the lower clamping device 2 of the present invention have openings on both the left and right sides, and the center of each opening of the upper clamping device 1 and the lower clamping device 2 is on the same vertical axis.

[0023] like Figure 1 As shown, the upper clamping device 1 and the lower clamping device 2 of the present invention are evenly provided with 6 holes and the centers of the corresponding holes on the clamping surfaces of the upper clamping device 1 and the lower clamping device 2 are all on the same vertical axis.

[0024] like Figure 1 As shown, the clamping surfaces of the upper clamping device 1 and the lower clamping device 2 of the present invention are both wavy, which increases the stress-bearing area of ​​the geotextile and reduces the slippage of the sample during stretching.

[0025] The needle plate 5 and the push rod 6 of the utility model are fixed on the sliding block. The needle plate 5 is used to fix the geotextile, and the push rod 6 is used to mark the elongation change of the geotextile after stretching and to ensure that the sliding blocks on both sides are at the same horizontal line. The needle plate 5 and the push rod 6 are fixed to the side of the sliding block 3 by bolts. Figure 2As shown, the needle plate 5 and the push rod 6 of the present invention are fixed to the side of the sliding block by bolts 9. The needle plate 5 is used to fix the geotextile, and the push rod 6 ensures that the sliding blocks on both sides are always kept at the same level.

[0026] like Figure 2 As shown, the needles of the needle plate 5 of the present invention are arranged in a staggered manner, thereby reducing local damage or errors caused by stress concentration.

[0027] The sliding block 3 of the present invention is embedded with rolling steel balls to reduce the friction between the sliding block and the sliding rod.

[0028] The number of the fixing devices of the utility model can be freely adjusted according to needs.

[0029] The upper side of the geotextile of the utility model is fixed to the upper clamping device 1, and the lower side of the geotextile is fixed to the lower clamping device 2. There are connecting rods in the center of the top of the upper clamping device 1 and the bottom of the lower clamping device 2. The upper connecting rod 7 and the lower connecting rod 8 are respectively fixed to the upper and lower ends of the universal testing machine. The universal testing machine is also connected to a computer and a video extensometer.

[0030] The working process of the transverse constraint stretching device for calibrating the elongation of geotextile in this embodiment is as follows: first, select the appropriate number of fixing devices according to the needs; fix the needle plate and the top rod to the side of the sliding block by bolts, fix the sliding rod to the opening of the lower clamping device, and then pass the fixing device and the upper clamping device through the sliding rod in sequence; then fix the upper connecting rod at the top of the upper clamping device and the lower connecting rod at the bottom of the lower clamping device to the upper and lower ends of the universal testing machine respectively; place the geotextile parallel to the fixing device to ensure that the geotextile is in a plane stretching state during the stretching process The upper and lower sides of the geotextile are fixed to the upper clamping device and the lower clamping device by bolts respectively, and the left and right sides of the geotextile are fixed by staggered needles on the needle plate; then pre-tension is applied to the geotextile and the sample size and tensile rate are set in the computer, the video extensometer is turned on to record the distance between the two push rods, and finally the universal strength machine is started to perform a transverse restraint tensile test on the geotextile. The tensile state of the sample is recorded by the tension value in the tensile software and the change displacement in the extensometer, and the universal testing machine is run until the sample is destroyed or the set displacement is reached and then stopped.

[0031] The above embodiments are intended only to illustrate the technical concepts and features of the present invention. Their purpose is to enable those familiar with the art to understand the contents of the present invention and implement them accordingly. They are not intended to limit the scope of protection of the present invention. Any equivalent changes or modifications based on the spirit of the present invention are intended to be included in the scope of protection of the present invention.

Claims

1. A transverse restraint stretching device for calibrating the elongation of a geotextile, characterized by: The invention comprises a clamping device and a plurality of fixing devices, wherein the clamping device comprises an upper clamping device (1), a lower clamping device (2), and a sliding rod (4); each fixing device comprises a sliding block (3), a needle plate (5), and a push rod (6); the needle plate (5) and the push rod (6) are both fixed on the sliding block (3); one end of the sliding rod (4) is fixed to the lower clamping device (2); the fixing device and the upper clamping device (1) pass through the sliding rod (4) in sequence; the sliding blocks (3) are evenly distributed between the upper clamping device (1) and the lower clamping device (2); the upper clamping device (1) and the lower clamping device (2) are symmetrically installed on the universal testing machine; the upper and lower sides of the geotextile are respectively fixed to the upper clamping device (1) and the lower clamping device (2); and the left and right sides of the geotextile are respectively fixed to the needle plates (5) of the fixing devices.

2. A transverse restraint stretching device for calibrating the elongation of a geotextile according to claim 1, characterized in that: The needle plate (5) and the push rod (6) are fixed on the sliding block. The needle plate (5) is used to fix the geotextile, and the push rod (6) is used to mark the elongation change of the geotextile after stretching and to ensure that the sliding blocks on both sides are in the same horizontal line. The needle plate (5) and the push rod (6) are both fixed to the side of the sliding block (3) by bolts.

3. The transverse restraint stretching device for calibrating the elongation of a geotextile according to claim 1, characterized in that: Six holes are evenly distributed on the clamping surfaces of the upper clamping device (1) and the lower clamping device (2) relative to each other; the clamping surfaces of the clamping devices are wavy, which is used to increase the stress-bearing area of ​​the geotextile and reduce the slippage of the sample during stretching.

4. The transverse restraint stretching device for calibrating the elongation of a geotextile according to claim 1, characterized in that: The sliding block (3) is embedded with a rolling steel ball (10) for reducing the sliding friction between the sliding block (3) and the sliding rod (4); the needles on the needle plate (5) are staggered and arranged for reducing local damage or error caused by stress concentration.

5. The transverse restraint stretching device for calibrating the elongation of a geotextile according to claim 1, characterized in that: The number of fixtures can be freely adjusted as needed.

Images