Device for testing bonding performance of synthetic fiber and cement based material during plastic stage

A technology of cement-based materials and synthetic fibers, which is applied in the direction of applying stable tension/pressure to test the strength of materials, etc., can solve the problems that synthetic fibers cannot be applied, and achieve the goal of preventing inaccurate test curves, ensuring accuracy, and high-precision measuring range Effect

Active Publication Date: 2012-06-27
JIANGSU SOBUTE NEW MATERIALS
View PDF7 Cites 17 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0006] The problem to be solved by the present invention is that the single fiber pull-out test commonly used at present is carried out on a micro

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Device for testing bonding performance of synthetic fiber and cement based material during plastic stage
  • Device for testing bonding performance of synthetic fiber and cement based material during plastic stage
  • Device for testing bonding performance of synthetic fiber and cement based material during plastic stage

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0031] In this example, polypropylene (PP) fibers were used to investigate the influence of the test time after molding on the fiber pull-out load-displacement curve, interface bond strength and fiber energy consumption. The bottom area of ​​the cement matrix holding the mold is 500mm 2 , the height is 7.5mm, that is, the fiber embedding depth is 7.5mm, and the braking control speed is 0.01mm / s. Fiber performance parameters, see Table 1; matrix mix ratio, see Table 2.

[0032] Table 1 Fiber performance parameters

[0033]

[0034] Table 2 Matrix mix ratio

[0035] water-binder ratio

[0036] The interface bond strength can be calculated according to formula (1):

[0037] τ=P max / πdL e (1)

[0038] Where: P max is the maximum load when the fiber is pulled out; d is the fiber diameter; L e is the fiber embedding depth.

[0039] During the drawing process, the fiber will go through two stages of debonding and pulling out, absorbing a lot of energy. Fib...

Embodiment 2

[0045] In this example, polypropylene (PP) and polyvinyl alcohol (PVA) fibers were used to investigate the effect of fiber types on the interfacial bond strength as the test time prolongs. The bottom area of ​​the cement matrix holding the mold is 500mm 2 , the height is 7.5mm, that is, the fiber embedding depth is 7.5mm, and the braking control speed is 0.01mm / s. The fiber performance parameters are shown in Table 4; the matrix mix ratio is the same as in Example 1, see Table 2.

[0046] Table 4 Fiber types and properties

[0047]

[0048] In this embodiment, the influence of the type of synthetic fiber on the interfacial bond strength is shown in image 3 .

[0049] From image 3 It can be seen that the interfacial bond strength between PVA and PP fibers is not much different within 6 hours after the cement matrix is ​​formed, but after 6 hours, the interfacial bond strength has been significantly improved, and the increase rate is relatively large. The reason why PV...

Embodiment 3

[0051] In this example, polyvinyl alcohol (PVA) fibers were used to investigate the influence of the matrix type on the bonding performance of the fiber-matrix interface. The bottom area of ​​the cement paste holding mold is 500mm 2 , the height is 7.5mm; the bottom area of ​​the mortar holding mold is 700mm 2 , with a height of 7.5mm. The brake control speed is 0.01mm / s. Polyvinyl alcohol (PVA) fiber performance parameter, with embodiment 2, sees Table 4; Matrix mix ratio, sees Table 5, and wherein sand is the standard sand that saturated surface is dry.

[0052] Table 5 Matrix mix ratio

[0053] water-binder ratio

[0054] From Figure 4 Two points can be seen, (1) After chemical debonding, the interfacial friction between PVA fiber and matrix continues to increase; (2) The interfacial bonding strength between fiber and mortar is higher than that of cement paste. This may be because the surface of the PVA fiber is continuously worn during the pulling out pro...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
Bottom areaaaaaaaaaaa
Heightaaaaaaaaaa
Login to view more

Abstract

A device for testing bonding performance of a synthetic fiber and cement based material during the plastic stage contains a force transducer, a holder, a drive system and a computer. The upper end of synthetic fiber is fixed by the holder and the lower end is embedded in a cement matrix. The holder is installed on the force transducer. The cement matrix is linked with the transmission system. The end of the synthetic fiber clamped by the holder is fixed. Under the control of the computer, the transmission system drives the cement matrix to move such that the synthetic fiber is pulled out from the cement matrix. The force transducer inputs force parameters measured during the pulling process into the computer for test and analysis. The invention solves problems of large measuring range and insufficient precision of present test equipment. According to the invention, the whole process is completed by the operation of the computer, and corresponding measurement and control parameters are arranged for the synthetic fiber, so as to guarantee validity and accuracy of the test result.

Description

technical field [0001] The invention belongs to the technical field of concrete, relates to plastic cracking of concrete, and is used for pulling out tests of synthetic fibers, in particular to a device for testing the interface bonding performance of synthetic fibers and cement-based materials in the plastic stage. Background technique [0002] With the advancement of modern concrete, concrete is developing towards high strength, high performance and multifunctionality. However, due to the widespread use of mineral admixtures and chemical admixtures, and the impact of harsh environments in some areas, concrete is prone to plastic cracking. The existence of plastic cracks provides a channel for the entry of harmful media, which seriously affects the safety and durability of concrete structures. Today, when the durability of concrete is paid more and more attention, it is particularly important to carry out the research on the key technology of concrete crack control. [00...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): G01N3/16
Inventor 刘加平李长风刘建忠阳知乾周华新崔巩
Owner JIANGSU SOBUTE NEW MATERIALS
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products