Study on Freeze-Thaw Performance of Polypropylene Fiber Reinforced Cement-Stabilized Aggregate

2012 ◽  
Vol 446-449 ◽  
pp. 2595-2598 ◽  
Author(s):  
Yin Hua Ma ◽  
Jian Yi Gu
Keyword(s):  
Compressive Strength ◽  
Mass Loss ◽  
Fiber Length ◽  
Loss Rate ◽  
Mass Loss Rate ◽  
Polypropylene Fiber ◽  
Strength Increase ◽  
Freeze Thaw ◽  
Splitting Strength ◽  
Reinforced Cement

In this paper, the authors study the anti-freeze-thaw performance of a new type of semi-rigid base material named polypropylene fiber reinforced cement-stabilized aggregate, and freeze-thaw mass loss rate, freeze-thaw compressive strength, freeze-thaw splitting strength are used to evaluate the effect of polypropylene fiber on the anti-freeze-thaw performance, and the relationship of polypropylene fiber content, polypropylene fiber length with the anti-freeze-thaw performance are analyzed. The test after 10 freeze-thaw cycle shows that the mix of polypropylene fiber increase the freeze-thaw compressive strength and freeze-thaw splitting strength, and decrease the mass loss rate greatly. At the same time, the paper also determine the reasonable fiber content and fiber length, under this mix proportion, the mass loss rate reduce by 80%, the freeze-thaw compressive strength increase more than 12.1% and freeze-thaw splitting strength increase more than 13.4%. This research has laid an important foundation for the follow-up research and practice.

scholarly journals Experimental Investigation on the Freeze–Thaw Resistance of Steel Fibers Reinforced Rubber Concrete

Materials ◽  
2020 ◽  
Vol 13 (5) ◽  
pp. 1260
Author(s):  
Tao Luo ◽  
Chi Zhang ◽  
Chaowei Sun ◽  
Xinchao Zheng ◽  
Yanjun Ji ◽  
...  
Keyword(s):  
Compressive Strength ◽  
Elastic Modulus ◽  
Mass Loss ◽  
Loss Rate ◽  
Bending Strength ◽  
Mass Loss Rate ◽  
Steel Fibers ◽  
Freeze Thaw ◽  
Four Point Bending ◽  
Rubber Concrete

The reuse of rubber in concrete results in two major opposing effects: an enhancement in durability and a reduction in mechanical strength. In order to strengthen the mechanical properties of rubber concrete, steel fibers were added in this research. The compressive strength, the four-point bending strength, the mass loss rate, and the relative dynamic elastic modulus of steel fiber reinforced rubber concrete, subjected to cyclic freezing and thawing, were tested. The effects of the content of steel fibers on the freeze–thaw resistance are discussed. The microstructure damage was captured and analyzed by Industrial Computed Tomography (ICT) scanning. Results show that the addition of 2.0% steel fibers can increase the compressive strength of rubber concrete by 26.6% if there is no freeze–thaw effect, but the strengthening effect disappears when subjected to cyclic freeze–thaw. The enhancement of steel fibers on the four-point bending strength is effective under cyclic freeze–thaw. The effect of steel fibers is positive on the mass loss rate but negative on the relative dynamic elastic modulus.

Effect of Mica Content in Stone Powder of Manufactured Sand on Performance of Cement Mortar

2014 ◽  
Vol 1044-1045 ◽  
pp. 624-628
Author(s):  
Jie Quan Xing ◽  
Shu Lin Zhan ◽  
Xin Yu Li
Keyword(s):  
Compressive Strength ◽  
Loss Rate ◽  
Cement Mortar ◽  
Mass Loss Rate ◽  
Strength Loss ◽  
Freezing Resistance ◽  
River Sand ◽  
Manufactured Sand ◽  
Freeze Thaw ◽  
Different Content

This paper studies the influence on compressive strength, freezing resistance and microstructure of cement mortar with different content of mica in stone powder, in the tests, manufactured sand with high content of mica and natural river sand were mixed with different proportion, and the content of stone powder was the same in mixed sand. Experiment results indicate that, with the increasing of mica content in stone powder, 28d and 60d compressive strength of cement mortar decreases obvious, mass loss rate and strength loss rate with 50 freeze-thaw cycles increase a little. Microstructure of cement mortar with higher content of mica is not compactly by SEM, the internal defects of cement hardened pastes could be increased because of the flake mica which surface is smooth, and it will cause the spread of micro crack.

Experimental Study on the Material and Environmental Property of Ancient Adobe Brick

2015 ◽  
Vol 1120-1121 ◽  
pp. 1485-1490
Author(s):  
Jian Li Yuan ◽  
Yun Yang ◽  
Sheng Nan Peng
Keyword(s):  
Experimental Study ◽  
Compressive Strength ◽  
Mass Loss ◽  
Power Function ◽  
Loss Rate ◽  
Mass Loss Rate ◽  
Damage Mechanism ◽  
Rammed Earth ◽  
Environmental Property ◽  
Rammed Earth Wall

Aiming at the environmental property and damage mechanism of ancient adobe buildings, the material components, compressive strength and freezing-thawing resisting performance of ancient adobe bricks were tested and analyzed. Based on test data, the power function relation between nondestructive rebound value and compressive strength of adobe bricks was established, and the nonlinear correlation curve between mass loss rate and freezing–thawing cycles of adobe bricks was also determined. The study shows that the compressive strength of ancient adobe brick is greater than that of adobe in traditional rammed earth wall, and ancient adobe brick is inferior to fired brick at the waterproofing quality and freezing resisting performance, it needs to adopt surface waterproofing measures for ancient adobe buildings to improve the resisting capacity to environmental erosion.

scholarly journals Corrosion Performance of Nano-TiO2-Modified Concrete under a Dry–Wet Sulfate Environment

Materials ◽  
2021 ◽  
Vol 14 (19) ◽  
pp. 5900
Author(s):  
Chao Xu ◽  
Hao-Hao Liao ◽  
You-Liang Chen ◽  
Xi Du ◽  
Bin Peng ◽  
...  
Keyword(s):  
Compressive Strength ◽  
Mass Loss ◽  
Loss Rate ◽  
Mass Loss Rate ◽  
Peak Stress ◽  
Xrd Analysis ◽  
Concrete Surface ◽  
Test Results ◽  
Nano Tio2 ◽  
Ordinary Concrete

This study compared the effects of the sulfate dry–wet cycle on the properties of ordinary concrete and nano-TiO2-modified concrete, including the mass loss rate, ultrasonic wave velocity, compressive strength, and XRD characteristics. In addition, a series of compression simulations carried out using the PFC2D software are also presented for comparison. The results show the following: (1) with an increase in dry–wet cycles, the damage to the concrete gradually increased, and adding nano-TiO2 into ordinary concrete can improve the material’s sulfate resistance; (2) after 50 sulfate dry–wet cycles, the mass loss rate of ordinary concrete was –3.744%, while that of nano-TiO2-modified concrete was −1.363%; (3) the compressive strength of ordinary concrete was reduced from 41.53 to 25.12 MPa (a reduction of 39.51%), but the compressive strength of nano-TiO2-modified concrete was reduced from 49.91 to 32.12 MPa (a reduction of 35.64%); (4) after a sulfate dry–wet cycle, the nano-TiO2-modified concrete surface produced white crystalline products, considered to be ettringite based on the XRD analysis; (5) when considering the peak stress and strain of the concrete samples, the numerical results agreed well with the test results, indicating the reliability of the method.

scholarly journals Frost Resistance Test Research on Hybrid Fiber Concrete Based on Range Analysis

2015 ◽  
Vol 9 (1) ◽  
pp. 292-297 ◽  
Author(s):  
Liu Faming ◽  
Zhao Lisha ◽  
Ma Jie
Keyword(s):  
Compressive Strength ◽  
Frost Resistance ◽  
Loss Rate ◽  
Steel Fiber ◽  
Polypropylene Fiber ◽  
Strength Loss ◽  
Hybrid Fiber ◽  
Freeze Thaw ◽  
Thaw Cycle ◽  
Fiber Concrete

The research of single doped fiber concrete is relatively mature. But the research about different varieties and different geometry shape of hybrid fiber concrete was very poor. Across the research in theory, hybrid fiber concrete can improve the balance of fiber three-dimensional distribution and coordinating role of aggregate and fiber, improve the efficiency of toughening crack resistance. In this paper, through the orthogonal experiment design method for hybrid fiber reinforced concrete, the mass and compressive strength loss rate after 50 times, 75 times, 100 times freeze-thaw cycle had been studied. Use range analysis quantified the influence level of various factors on the mechanical properties. It was analyzed the hybrid fiber influence on improving the efficiency of toughening crack resistance and frost resistance. It is concluded that adding the fiber can enhance the performance of concrete frost resistance. Long steel fiber have great influence on compressive strength loss rate of hybrid fiber concrete, such as the compressive strength loss rate was reached 65.47% after 75 times freeze-thaw cycle. Short steel fiber have certain influence on mass loss of concrete which were after less freeze-thaw cycles. The influence of polypropylene fiber on concrete frost resistance increases significantly, the effect can reach 36.78% after 50 times of freeze-thaw cycle. The optimal combination of the hybrid fiber concrete ultimately determined was A2B2C3 (simultaneously mixed with 50kg/m3 short steel fiber and long steel fiber as well as 0.9kg/m polypropylene fiber). The addition of steel fiber and polypropylene fiber are both beneficial to increase the internal air content of concrete, strengthening the frost resistance of concrete. However, with the increase of dosage, the internal porosity of concrete is gradually increasing, the density is reduced, and, as a result, the corresponding increase of the compressive strength loss rate is also improved.

Experimental Study on Frost Resistance Properties of Pumice Mixed Aggregate Concrete

2012 ◽  
Vol 476-478 ◽  
pp. 1661-1664
Author(s):  
Jun Fang Huo ◽  
Jian Jun Chu ◽  
Hui Yang
Keyword(s):  
Elastic Modulus ◽  
Mass Loss ◽  
Frost Resistance ◽  
Loss Rate ◽  
Mass Loss Rate ◽  
Strength Loss ◽  
Dynamic Elastic Modulus ◽  
Aggregate Concrete ◽  
Freeze Thaw ◽  
Thaw Cycle

Different amount of pumice were used to replace gravel to make mixed aggregate concrete, the fast freeze-thaw cycle test were conducted and the influence of pumice rate substitution to the frost resistance properties of concrete were studied.The mass loss rate, strength loss and relative dynamic elastic modulus were regarded as the evaluation index of frost resistance properties of concrete. Results showed that the mass loss rate and strength loss rate gradually decreased and the relative dynamic elastic modulus gradually increased with the increase of pumice rate, the mass loss rate, strength loss rate and the relative dynamic elastic modulus gradually decreased with the increase of freeze-thaw cycles. Polypropylene fibers could reduce the strength loss rate, improved the relative dynamic elastic modulus, but had little effect to improve the mass loss. Through the frost resistance, the frost resistance of concrete improved with the increase of pumice content, at the same time, polypropylene fiber also could improve the frost resistance of concrete.

Sign in / Sign up

Export Citation Format

Share Document