Energy saving benefit, mechanical performance, volume stabilities, hydration properties and products of low heat cement-based materials

The influence of graphene oxide (GO) and polyvinyl alcohol (PVA) fiber on the mechanical performance, durability, and microstructure of cement-based materials was investigated in this study. The results revealed that compared with a control sample, the mechanical strength and durability of cement-based materials were significantly improved by adding PVA fiber and GO. The compressive and flexural strength at 28 d were increased by 30.2% and 39.3%, respectively. The chloride migration coefficient at 28 d was reduced from 7.3 × 10−12 m2/s to 4.3 × 10−12 m2/s. Under a sulfate corrosion condition for 135 d, the compressive and flexural strength still showed a 13.9% and 12.3% gain, respectively. Furthermore, from the Mercury Intrusion Porosimetry (MIP) test, with the incorporation of GO, the cumulative porosity decreased from more than 0.13 cm3/g to about 0.03 cm3/g, and the proportion of large capillary pores reduced from around 80% to 30% and that of medium capillary pores increased from approximately 20% to 50%. Scanning electron microscope (SEM) images showed a significant amount of hydration products adhering to the surface of PVA fiber in the GO and PVA fiber modified sample. The addition of GO coupling with PVA fiber in cement-based materials could promote hydration of cement, refine the microstructure, and significantly improve mechanical strength and durability.

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Influence of coarse aggregate angularity on the mechanical performance of cement-based materials

Construction and Building Materials ◽

10.1016/j.conbuildmat.2019.01.135 ◽

2019 ◽

Vol 204 ◽

pp. 184-192 ◽

Cited By ~ 9

Author(s):

Seung Jae Lee ◽

Chang Hoon Lee ◽

Moochul Shin ◽

Sumana Bhattacharya ◽

Yu Feng Su

Keyword(s):

Coarse Aggregate ◽

Mechanical Performance ◽

Cement Based Materials

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Synergistic effect of nano-silica and silica fume on hydration properties of cement-based materials

Journal of Thermal Analysis and Calorimetry ◽

10.1007/s10973-019-08929-8 ◽

2019 ◽

Vol 140 (5) ◽

pp. 2225-2235

Author(s):

Yansheng Wang ◽

Zhenhai Xu ◽

Jinbang Wang ◽

Zonghui Zhou ◽

Peng Du ◽

...

Keyword(s):

Synergistic Effect ◽

Silica Fume ◽

Nano Silica ◽

Hydration Properties ◽

Cement Based Materials

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Influence of Carbon Nanofibers on the Mechanical Performance and Microstructure of Cement-Based Materials

Nanoscience and Nanotechnology Letters ◽

10.1166/nnl.2013.1679 ◽

2013 ◽

Vol 5 (10) ◽

pp. 1112-1118 ◽

Cited By ~ 4

Author(s):

Bao-Min Wang ◽

Yuan Zhang ◽

Shuai Liu

Keyword(s):

Carbon Nanofibers ◽

Mechanical Performance ◽

Cement Based Materials

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Physical and Chemical Influence of Polyacrylate Latex on Cement Mortars

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.261-263.807 ◽

2011 ◽

Vol 261-263 ◽

pp. 807-811 ◽

Cited By ~ 1

Author(s):

Ye Tian ◽

Zong Jin Li ◽

Hong Yan Ma ◽

Xian Yu Jin ◽

Nan Guo Jin

Keyword(s):

Pore Structure ◽

Cement Hydration ◽

Bending Strength ◽

Mechanical Performance ◽

Air Entrainment ◽

Hydration Products ◽

Cement Mortars ◽

Cement Based Materials ◽

Physical And Chemical ◽

Chemical Influence

In this research, the physical and chemical influence of polyacrylate (PA) latex on cement-based materials were studied using polymer modified mortars with polymer/cement (P/C) ratios of 0%, 5% and 10%. Physically, the mechanical performance of PA latex modified mortars was investigated with compression toughness energy and bending strength. Further more, a comparison of the pore structure and porosity between PA latex modified and unmodified mortars was conducted. The chemical reactions between PA polymer and cement hydrates were clarified with thermogravimetric (TG) analysis. It can be concluded from this research that PA polymer can refine the pore structure of cement mortars and link the cement hydration products together chemically. While, at the same time, PA latex addition can cause air entrainment which will weaken the physical behavior of cement mortars. So there is an optimum P/C ratio to achieve the best mechanical properties. And in this research, the optimum P/C ratio is 5%.

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Effect of curing temperature on hydration properties of waste glass powder in cement-based materials

Journal of Thermal Analysis and Calorimetry ◽

10.1007/s10973-014-4095-6 ◽

2014 ◽

Vol 119 (1) ◽

pp. 47-55 ◽

Cited By ~ 23

Author(s):

Shuhua Liu ◽

Guoshuai Xie ◽

Shu Wang

Keyword(s):

Glass Powder ◽

Waste Glass ◽

Curing Temperature ◽

Hydration Properties ◽

Waste Glass Powder ◽

Cement Based Materials

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Effects of Red Mud Addition in the Microstructure, Durability and Mechanical Performance of Cement Mortars

Applied Sciences ◽

10.3390/app9050984 ◽

2019 ◽

Vol 9 (5) ◽

pp. 984 ◽

Cited By ~ 5

Author(s):

José Ortega ◽

Marta Cabeza ◽

Antonio Tenza-Abril ◽

Teresa Real-Herraiz ◽

Miguel Climent ◽

...

Keyword(s):

Portland Cement ◽

Red Mud ◽

Mechanical Performance ◽

Network Evolution ◽

Cement Industry ◽

Pozzolanic Activity ◽

Great Effort ◽

Chloride Ingress ◽

Cement Mortars ◽

Cement Based Materials

Recently, there has been a great effort to incorporate industrial waste into cement-based materials to reach a more sustainable cement industry. In this regard, the Bayer process of obtaining alumina from bauxite generates huge amounts of waste called red mud. Few research articles have pointed out the possibility that red mud has pozzolanic activity. In view of that, the objective of this research is to analyse the short-term effects in the pore structure, mechanical performance and durability of mortars which incorporate up to 20% of red mud as a clinker replacement. As a reference, ordinary Portland cement and fly ash Portland cement mortars were also studied. The microstructure was characterised through mercury intrusion porosimetry and non-destructive impedance spectroscopy, which has not previously been used for studying the pore network evolution of red mud cement-based materials. The possible pozzolanic activity of red mud has been checked using differential scanning calorimetry. The non-steady state chloride migration coefficient and the mechanical properties were studied too. According to the results obtained, the addition of red mud entailed a greater microstructure refinement of the mortar, did not worsen the resistance against chloride ingress and reduced the compressive strength compared to control binders.

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Energy-saving mechanisms in walking and running

Journal of Experimental Biology ◽

10.1242/jeb.160.1.55 ◽

1991 ◽

Vol 160 (1) ◽

pp. 55-69 ◽

Cited By ~ 27

Author(s):

R. M. Alexander

Keyword(s):

Energy Saving ◽

Mechanical Performance ◽

Elastic Strain Energy ◽

Metabolic Energy ◽

Elastic Recoil ◽

Work Requirements ◽

Terrestrial Locomotion ◽

Speed Parameter ◽

The Relationship ◽

Positive Work

Energy can be saved in terrestrial locomotion in many different ways. The maximum shortening speeds (Vmax) of the muscles can be adjusted to their optimum values for the tasks required of them. The moments exerted by the muscles at different joints can be adjusted to keep the ground force in line with the leg so that muscles do not work against each other. The joints of the legs can be kept as straight as possible, minimizing muscle forces and work requirements. Walking gaits should be selected at low Froude numbers (a dimensionless speed parameter) and running gaits at high Froude numbers. Tendon and other springs can be used to store elastic strain energy and to return it by elastic recoil. This paper aims to show how these energy-saving mechanisms work and to what extent mammals exploit them. Arguments based on our rather limited knowledge of the relationship between the mechanical performance of muscle and its metabolic energy consumption are used throughout. They suggest that muscles that are optimally adapted for their tasks in running should do positive work with constant efficiency.

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