Effect of curing method on compressive strength of rapid hardening sulphoaluminate cement mortar at -10 °C

The effects of wood fiber and polypropylene fiber on the mechanical performance, drying shrinkage and moisture loss of sulphoaluminate cement (SAC) mortar were studied. The experimental results show that wood fiber and polypropylene fiber can both improve the flexural strength of the mortar and reduce drying shrinkage ratio and moisture loss at different ages. Polypropylene fiber can also improve the late compressive strength of the mortar. Adding 0.3% mass fraction of wood fiber, the drying shrinkage ratio and moisture loss of the motar reach minimum values. The drying shrinkage ratio reduces to 0.029% at 28d. Moisture loss reduces to 0.4%. Adding 0.5% mass fraction of polypropylene fiber, the drying shrinkage ratio and moisture loss of the motar also reach minimum values. The drying shrinkage ratio reduces to 0.03% at 28d and moisture loss reduces to 0.39%.

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Redispersible Polymer Powder-Modified Sulphoaluminate Cement Mortar

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.726.495 ◽

2017 ◽

Vol 726 ◽

pp. 495-499 ◽

Cited By ~ 4

Author(s):

Peng Du ◽

Zong Hui Zhou ◽

Zheng Mao Ye ◽

Xin Cheng

Keyword(s):

Compressive Strength ◽

Flexural Strength ◽

Compression Ratio ◽

Bonding Strength ◽

Cement Mortar ◽

Morphological Structure ◽

Sulphoaluminate Cement ◽

Polymer Powder ◽

Powder Particles ◽

Redispersible Polymer Powder

The super-softening property of redispersible polymer powder can improve the flexibility of cement-based materials while guarantees other work performances. In this study, the influences of different mixing amounts of redispersible polymer powders on the compressive strength, flexural strength, flexural compression ratio and bonding strength of sulphoaluminate cement mortar were investigated. The microscopic morphological structure of redispersible polymer powder-modified sulphoaluminate cement mortar was also observed through SEM to analyse the influence mechanism. Results show that, with the mixing amount of 2.0%, the compressive strength of cement mortar was improved. This mixing amount also increased the 28d flexural strength to 8.21 MPa (5.0% improvement) and 14d bonding strength to 5.6 MPa (27.3% improvement). Addition of more redispersible polymer powder resulted in the increase in flexural compression ratio because the powder particles formed water-insoluble continuous polymer colloidal film in hardened paste. This film generated a network with cement dydration products throughout the paste, consequently promoting the flexibility of cement.

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Microbially Induced Carbonate Precipitation in Sulphoaluminate Cement Mortar

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.454.234 ◽

2013 ◽

Vol 454 ◽

pp. 234-237

Author(s):

Xiao Lu Yuan ◽

Shi Hua Zhou ◽

Wei Min Hu ◽

Dong Mei Liu

Keyword(s):

Compressive Strength ◽

Flexural Strength ◽

Cement Mortar ◽

Carbonate Precipitation ◽

Sulphoaluminate Cement ◽

Microbially Induced Carbonate Precipitation

This paper investigated microbially induced carbonate precipitation in sulphoaluminate cement mortar. Urea and calcium of varied amounts were studied on the growth of microorganisms, the degradation of urea and the precipitation production. Compressive strength and flexural strength of sulphoaluminate cement mortar were measured and discussed. Results indicate that urea of 10g/L and calcium of 2mmol/L achieved favorable microorganism growth and the production of precipitation, which was composed of large amounts of calcite as well as small vaterite. Biodeposition increased the compressive strength and the flexural strength of sulphoaluminate cement mortar by 10% and 21%, respectively.

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Impermeability of Sulphoaluminate Cement Mortar Modified by Redispersible Polymer Powders

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.168-170.1886 ◽

2010 ◽

Vol 168-170 ◽

pp. 1886-1890 ◽

Cited By ~ 2

Author(s):

Zheng Mao Ye ◽

Wen Chen ◽

Xin Cheng

Keyword(s):

Compressive Strength ◽

Flexural Strength ◽

Mass Fraction ◽

Cement Mortar ◽

Total Porosity ◽

Gap Filling ◽

Sulphoaluminate Cement ◽

Cement Mortars ◽

Film Forming ◽

Polymer Powders

The impermeability and other performance of sulphoaluminate cement were studied, which mixed with redispersible polymer powders. With the help of SEM and mercury intrusion apparatus, the morphology of the hydrates and the pore structure of the cement mortars were observed. The impermeability mechanism of redispersible polymer powders in sulphoaluminate cement mortar was analyzed. The results show that sulphoaluminate cement mortar could be modified by adding redispersible polymer powders. The flexural strength of sulphoaluminate cement mortar could be increased by adding redispersible polymer powders, and compressive strength of sulphoaluminate cement mortar could also be increased to a certain extent. When the mass fraction of redispersible polymer powders was 0.9%, the flexural strength and compressive strength reached 9.2 MPa and 52.5 MPa. When small amount of redispersible polymer powders was added, the impermeability of modified sulphoaluminate cement mortar was improved significantly. When the mass fraction of redispersible polymer powders exceeded 0.9%, impermeability of Sulphoaluminate cement mortar would not be improved significantly. Due to redispersible powders gap filling and film forming, the interface of cement and aggregate is more closed, total porosity decreased and unharmful porosity increased when redispersible polymer powders is added.

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Strength and Water-Repelling Properties of Cement Mortar Mixed with Water Repellents

Materials ◽

10.3390/ma14185407 ◽

2021 ◽

Vol 14 (18) ◽

pp. 5407

Author(s):

Hyeju Kang ◽

Sukpyo Kang ◽

Byoungky Lee

Keyword(s):

Contact Angle ◽

Compressive Strength ◽

Water Contact Angle ◽

Cement Mortar ◽

Contact Angles ◽

Water Repellent ◽

Water Contact ◽

Rapid Hardening ◽

Before And After ◽

Large Water

In this study, the compressive strength and water contact angle of mortar specimens prepared by mixing two types of water repellent with ordinary Portland cement (OPC) and rapid-hardening cement mortar were measured before and after surface abrasion. In addition, the hydration products and chemical bonding of cement mortar with the repellents were examined using X-ray diffraction (XRD), thermogravimetry-differential thermal analysis (TG-DTA), and Fourier-transform infrared spectroscopy (FT-IR) to evaluate the performance of these cement mortar mixtures as repair materials. We found that the fast-hardening cement mortar mixture containing the oligomer water repellent showed the best performance with a high compressive strength and large water contact angle. With the oligomer water repellent, the rapid-hardening cement mortar mixture showed contact angles of 131° and 126° even after a 2 mm abrasion, thereby confirming that the water repellent secured hydrophobicity through strong bonding with the entire cement mortar as well as its surface. The compressive strengths were found to be 34.5 MPa at 3 h and 54.8 MPa at 28 days, confirming that hydration occurred well despite the addition of water repellent.

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Resistance to Hydrochloric Acid Corrosion of Latex Modified Sulphoaluminate Cement Mortar

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.174-177.1372 ◽

2012 ◽

Vol 174-177 ◽

pp. 1372-1375 ◽

Cited By ~ 3

Author(s):

Wei Dong Hua ◽

Hong Yi Jiang ◽

Zi Xia Zhou

Keyword(s):

Compressive Strength ◽

Hydrochloric Acid ◽

Flexural Strength ◽

Weight Change ◽

Cement Mortar ◽

Acid Corrosion ◽

Change Rate ◽

Cement Ratio ◽

Sulphoaluminate Cement ◽

Acrylic Latex

The correlation between the ratio of styrene-acrylic latex to sulphoaluminate cement and the resistance of latex modified sulphoaluminate cement mortar to hydrochloric acid corrosion was investigated. The weight change rate, compressive strength, and flexural strength of various latex modified cement mortar in the hydrochloric acid solution at different ages were tested and the samples appearance was observed. The results show that the resistance of latex modified sulphoaluminate cement mortar to hydrochloric acid corrosion is related to the latex/cement ratio. With the increase of the latex/cement ratio, the resistance performance of sulphoaluminate cement mortar to hydrochloric acid corrosion was improved firstly and then decreased. When the polymer/cement ratio was 0.2, the latex modified cement mortar presented the highest ability in compressive strength, flexural strength, weight change rate, and the appearance, showing its excellent resistance to hydrochloric acid corrosion.

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Effect of Redispersible Powders on Frost Resistance of Sulphoaluminate Cement Mortar

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.174-177.716 ◽

2012 ◽

Vol 174-177 ◽

pp. 716-720

Author(s):

Zheng Mao Ye ◽

Liancong Zheng ◽

Yong Zhang ◽

Xin Cheng

Keyword(s):

Frost Resistance ◽

Cement Mortar ◽

Mercury Porosimetry ◽

Resistance Mechanism ◽

Micro Structure ◽

Rapid Hardening ◽

Sulphoaluminate Cement

Frost Resistance of rapid hardening sulphoaluminate cement was modified with redispersible powders. Frost resistance and strength of sulphoaluminate cement mortar were tested. With the help of SEM and mercury porosimetry, the morphology of the hydrates and the micro-structure of the mortar were observed. The frost resistance mechanism of redispersible powders in the mortar is analyzed. The results show that the frost resistance of sulphoaluminate cement mortar could be improved significantly by mixing redispersible powders. The optimal content of redispersible powders is 0.9%.

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Incorporation of Iraqi Rocks in the Production of Eco-Friendly Cement Mortar

Engineering and Technology Journal ◽

10.30684/etj.v38i10a.1479 ◽

2020 ◽

Vol 38 (10A) ◽

pp. 1522-1530

Author(s):

Rawnaq S. Mahdi ◽

Aseel B. AL-Zubidi ◽

Hassan N. Hashim

Keyword(s):

Mechanical Properties ◽

Thermal Conductivity ◽

Compressive Strength ◽

Water Absorption ◽

Structural Properties ◽

Mechanical Milling ◽

Cement Mortar ◽

Cement Mortars

This work reports on the incorporation of Flint and Kaolin rocks powders in the cement mortar in an attempt to improve its mechanical properties and produce an eco-friendly mortar. Flint and Kaolin powders are prepared by dry mechanical milling. The two powders are added separately to the mortars substituting cement partially. The two powders are found to improve the mechanical properties of the mortars. Hardness and compressive strength are found to increase with the increase of powders constituents in the cement mortars. In addition, the two powders affect water absorption and thermal conductivity of the mortar specimens which are desirable for construction applications. Kaolin is found to have a greater effect on the mechanical properties, water absorption, and thermal conductivity of the mortars than Flint. This behavior is discussed and analyzed based on the compositional and structural properties of the rocks powders.

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Mechanical Behavior of Brick Masonry in an Acidic Atmospheric Environment

Materials ◽

10.3390/ma12172694 ◽

2019 ◽

Vol 12 (17) ◽

pp. 2694 ◽

Cited By ~ 2

Author(s):

Shansuo Zheng ◽

Lihua Niu ◽

Pei Pei ◽

Jinqi Dong

Keyword(s):

Mechanical Properties ◽

Compressive Strength ◽

Fly Ash ◽

Acid Rain ◽

Cement Mortar ◽

Brick Masonry ◽

Atmospheric Environment ◽

Peak Strain ◽

Lime Mortar ◽

Attenuation Model

In order to evaluate the deterioration regularity for the mechanical properties of brick masonry due to acid rain corrosion, a series of mechanical property tests for mortars, bricks, shear prisms, and compressive prisms after acid rain corrosion were conducted. The apparent morphology and the compressive strength of the masonry materials (cement mortar, cement-lime mortar, cement-fly ash mortar, and brick), the shear behavior of the masonry, and the compression behavior of the masonry were analyzed. The resistance of acid rain corrosion for the cement-lime mortar prisms was the worst, and the incorporation of fly ash into the cement mortar did not improve the acid rain corrosion resistance. The effect of the acid rain corrosion damage on the mechanical properties for the brick was significant. With an increasing number of acid rain corrosion cycles, the compressive strength of the mortar prisms, and the shear and compressive strengths of the brick masonry first increased and then decreased. The peak stress first increased and then decreased whereas the peak strain gradually increased. The slope of the stress-strain curve for the compression prisms gradually decreased. Furthermore, a mathematical degradation model for the compressive strength of the masonry material (cement mortar, cement-lime mortar, cement-fly ash mortar, and brick), as well as the shear strength attenuation model and the compressive strength attenuation model of brick masonry after acid rain corrosion were proposed.

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Preparation of Electric- and Magnetic-Activated Water and Its Influence on the Workability and Mechanical Properties of Cement Mortar

Sustainability ◽

10.3390/su13084546 ◽

2021 ◽

Vol 13 (8) ◽

pp. 4546

Author(s):

Kaiyue Zhao ◽

Peng Zhang ◽

Bing Wang ◽

Yupeng Tian ◽

Shanbin Xue ◽

...

Keyword(s):

Magnetic Field ◽

Mechanical Properties ◽

Compressive Strength ◽

Flexural Strength ◽

Cement Paste ◽

Cement Mortar ◽

Environmental Issues ◽

Chemical Admixtures ◽

Untreated Water ◽

Alternating Voltage

Cement-based materials prepared with activated water induced by a magnetic field or electric field represent a possible solution to environmental issues caused by the worldwide utilization of chemical admixtures. In this contribution, electric- and magnetic-activated water have been produced. The workability and mechanical properties of cement mortar prepared with this activated water have been investigated. The results indicate that the pH and absorbance (Abs) values of the water varied as the electric and magnetic field changed, and their values increased significantly, exhibiting improved activity compared with that of the untreated water. In addition, activated water still retains activity within 30 min of the resting time. The fluidity of the cement paste prepared with electric-activated water was significantly larger than that of the untreated paste. However, the level of improvement differed with the worst performance resulting from cement paste prepared with alternating voltage activated water. In terms of mechanical properties, both compressive strength and flexural strength obtained its maximum values at 280 mT with two processing cycles. The compressive strength increased 26% as the curing time increased from 7 days to 28 days and flexural strength increased by 31%. In addition, through the introduction of magnetic-activated water into cement mortar, the mechanical strength can be maintained without losing its workability when the amount of cement is reduced.

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