Evaluation of Effects of Emulsified Asphalt on Strength and Freeze-thaw Mass-loss Rate of Cement Mortar

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.

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

Materials ◽

10.3390/ma13051260 ◽

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.

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Development of the Fog Seal Layer Characterized by Durability in Terms of Skid Resistance

Advances in Materials Science and Engineering ◽

10.1155/2021/6210875 ◽

2021 ◽

Vol 2021 ◽

pp. 1-18

Author(s):

Yingjun Jiang ◽

Jiangtao Fan ◽

Pengyu Lv ◽

Kejia Yuan ◽

Yong Yi ◽

...

Keyword(s):

Mass Loss ◽

Loss Rate ◽

Mass Loss Rate ◽

Reduction Rate ◽

Skid Resistance ◽

Wheel Wear ◽

Bonding Performance ◽

Resistance Durability ◽

The One ◽

Emulsified Asphalt

In this paper, based on the thermosetting properties, bonding performance, high-temperature water damage resistance, and aging resistance properties of epoxy-emulsified asphalt, the best formulation of epoxy emulsified asphalt as a skid resistance fog sealing asphalt is studied. Through accelerated wheel wear and other tests, the effects of the ratio of the amount of skid resistance particles to the amount of epoxy emulsified asphalt, the total amount of skid resistance fog seal asphalt, and the construction process on the skid resistance durability of the skid resistance fog seal were studied. The results show that the epoxy emulsified asphalt formula code A80 (E2) (emulsified asphalt : water-based epoxy = 80 : 20) is the best formula; when the proportion of emery and epoxy emulsified asphalt is 1 : 1, the British Pendulum Number (BPN) reduction rate of the skid resistance fog seal-test piece worn 100,000 times was 27.4%. Compared with the same period, the reduction rate was reduced by 4.6% on average, with the smallest mass loss rate and the best skid resistance durability. When the total amount of skid resistance fog seal asphalt is 1.2 kg/m2, the BPN reduction rate of the skid resistance fog seal specimen worn 100,000 times was 27.4%, which is an average reduction of 5.8% over the same period, and the mass loss rate is the smallest, and the skid resistance durability optimal. When using the premixed process, the BPN of the specimen was reduced by 13.2% after abrasion of 100,000 times. Compared with the “one asphalt and one sand” and “double asphalt and one sand” molded specimens, the mass loss rate was reduced by 15.0%, 4eU&7.2%, showing the best skid resistance performance. The results can provide guidance for the design and construction of AC-13 and other pavement skid resistance fog seals.

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

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.446-449.2595 ◽

2012 ◽

Vol 446-449 ◽

pp. 2595-2598 ◽

Cited By ~ 1

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.

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Experimental Study on Frost Resistance Properties of Pumice Mixed Aggregate Concrete

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.476-478.1661 ◽

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.

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