Concrete multi-factors durability experimental device under bent tension stress and environment coupled action

An experimental device and concrete technology, applied in the direction of applying a stable bending force to test the strength of materials, material inspection products, etc., can solve the problems of low control precision of stress wrench, change of bolt friction coefficient, occupying test space, etc., and achieve accurate test results Reliable, uniform and accurate force, and simple force application method

Inactive Publication Date: 2008-10-01
SOUTHEAST UNIV
View PDF0 Cites 31 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The advantage of the lever loading device is that the principle is simple, the load controllability is relatively good, and it is not affected by temperature; the disadvantage is that the loading efficiency is relatively low. When loading 50% bending stress of a 40mm×40mm×160mm specimen, the length of the lever needs 0.6 meters, which takes up a lot of test space. When multi-factor durability tests such as loading-freeze-thawing and loading-carbonization are carried out at the same time, the test box of the test instrument can hardly accommodate it. If the length of the lever arm is reduced, the load accuracy will be reduced.
The advantages of the rod loading system are easy to operate, the device is small in size, and can be adapted to existing standard carbonization boxes and freeze-thaw testers and other durability devices to achieve stress-environment (carbonization, freeze-thaw, etc.) coupling; the disadvantage is the stress wrench The control accuracy is low, and it is easily affected by the corrosion of bolts, etc., which further reduces the load control accuracy; the stress will relax greatly during the long-term load process
In addition, this method is not suitable for loading in freeze-thaw tests, because the thermal expansion and contraction of the tie rods will cause large errors when the temperature changes. Errors caused by deformation and surface peeling cannot be ignored, and the bolts tightened with a stress wrench may be immersed in water or solution during the freezing and thawing process, which will cause changes in the friction coefficient of the bolts. A small change in the friction coefficient will caus

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
  • Concrete multi-factors durability experimental device under bent tension stress and environment coupled action
  • Concrete multi-factors durability experimental device under bent tension stress and environment coupled action
  • Concrete multi-factors durability experimental device under bent tension stress and environment coupled action

Examples

Experimental program
Comparison scheme
Effect test

Example Embodiment

[0036] Example 1:

[0037] Concrete mix ratio (kg / m 3 ): Cement-275, fly ash-183, sand-705, gravel-1127, water-160, polycarboxylic acid superplasticizer-3.2

[0038] According to the above ratio, after mixing with a forced mixer, pour the fresh concrete into a steel mold with a size of 70mm×70mm×280mm, vibrate the shaker for 30s, leave it in the laboratory for 24h and demould, and then remove the concrete sample Put it into a standard curing room (temperature (20±3°C, relative humidity above 90%)) to cure to the specified age and then take it out. Use the MTS810 testing machine to conduct four-point bending strength test on the cured concrete specimen, and pass the control during the experiment The loading rate is 0.01mm / s. In the four-point bending test, the center span of the lower bottom surface is 210mm, and the span of the upper surface fulcrum is 70mm. According to the measured bending strength, 0.20, 0.35, 0.50, 0.65, 0.80 are applied to the concrete specimens. Two stress l...

Example Embodiment

[0039] Example 2:

[0040] Concrete mix ratio (kg / m 3 ): Cement-275, fly ash-183, sand-705, gravel-1127, water-160, polycarboxylic acid superplasticizer-3.2

[0041] According to the above ratio, after mixing with a forced mixer, pour the fresh concrete into a steel mold with a size of 70mm×70mm×280mm, vibrate the shaker for 30s, leave it in the laboratory for 24h and demould, and then remove the concrete sample Put it into a standard curing room (temperature (20±3°C, relative humidity above 90%)) to cure to the specified age and then take it out. Use the MTS810 testing machine to conduct four-point bending strength test on the cured concrete specimen, and pass the control during the experiment The loading rate is 0.01mm / s. In the four-point bending test, the center span of the lower bottom surface is 210mm, and the span of the upper surface fulcrum is 70mm. According to the measured bending strength, 0.20, 0.35, 0.50, 0.65, 0.80 are applied to the concrete specimens. A stress lev...

Example Embodiment

[0042] Example 3:

[0043] Concrete mix ratio (kg / m 3 ): Cement-275, fly ash-183, sand-705, gravel-1127, water-160, polycarboxylic acid superplasticizer-3.2

[0044] According to the above ratio, after mixing with a forced mixer, pour the fresh concrete into a steel mold with a size of 70mm×70mm×280mm, vibrate the shaker for 30s, leave it in the laboratory for 24h and demould, and then remove the concrete sample Put it into a standard curing room (temperature (20±3°C, relative humidity above 90%)) to cure to the specified age and then take it out. Use the MTS810 testing machine to conduct four-point bending strength test on the cured concrete specimen, and pass the control during the experiment The loading rate is 0.01mm / s. In the four-point bending test, the center span of the lower bottom surface is 210mm, and the span of the upper surface fulcrum is 70mm. According to the measured bending strength, 0.20, 0.35, 0.50, 0.65, 0.80 are applied to the concrete specimens. A stress lev...

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

No PUM Login to view more

Abstract

In a concrete multi-factor durability experimental device under the action of the bend-pulling stress and the environment coupling, lower part of the pulling rod (6) is connected to a lower pressing board (9); the upper part of the pulling rod (6) presses a stress sensor (1) on the pulling board (2) via the screw cap (3) traversing the upper pressing board (5) and pulling board (2); a spring (4) is arranged between the pulling board (2) and the upper pressing board (5); concrete test pieces (8) are arranged between the upper pressing board (5) and the lower pressing board (9); a mat stick (7) is arranged between the concrete test pieces and between the concrete test piece (8) and the upper pressing board (5) or the lower pressing board (9); two sides of the concrete test piece (8) are arranged with a constant force holding meter (10); the constant force holding meter (10) is connected to the non-metal supersonic testing meter (11). The device is suitable for the big size concrete test piece, retaining the no stress loosing state in the process of loading in a long term.

Description

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

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
Owner SOUTHEAST UNIV
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

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2023 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap