Understanding the shrinkage compensating ability of type K expansive agent in concrete

Previous research studies have indicated that using fibres to improve crack resistance and applying expansive agent (EA) to compensate shrinkage are both effective methods to mitigate shrinkage cracking of concrete, and the additions of both fibres and EA can enhance the other performance attributes of concrete. In this study, an EA was added to fibre reinforced concrete (FRC) to produce concrete mixes with various water/binder (W/B) ratios, steel fibre (SF) contents and EA contents for testing of their workability and compressive properties. The test results showed that adding EA would slightly increase the superplasticiser (SP) demand and decrease the compressive strength, Young’s modulus and Poisson’s ratio, but significantly improve the toughness and specific toughness of the steel FRC produced. Such improvement in toughness may be attributed to the pre-stress of the concrete matrix and the confinement effect of the SFs due to the expansion of the concrete and the restraint of the SFs against such expansion.

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Expression of human endogenous retrovirus type K envelope glycoprotein in insect and mammalian cells.

Journal of Virology ◽

10.1128/jvi.71.4.2747-2756.1997 ◽

1997 ◽

Vol 71 (4) ◽

pp. 2747-2756 ◽

Cited By ~ 18

Author(s):

R R Tönjes ◽

C Limbach ◽

R Löwer ◽

R Kurth

Keyword(s):

Envelope Glycoprotein ◽

Mammalian Cells ◽

Endogenous Retrovirus ◽

Human Endogenous Retrovirus ◽

Type K

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Effects of plastic expansive agent on the fluidity, mechanical strength, dimensional stability and hydration of high performance cementitious grouts

Construction and Building Materials ◽

10.1016/j.conbuildmat.2020.118204 ◽

2020 ◽

Vol 243 ◽

pp. 118204

Author(s):

Guofang Zhang ◽

Dawei Qiu ◽

Shunxiang Wang ◽

Peiming Wang

Keyword(s):

Mechanical Strength ◽

Dimensional Stability ◽

High Performance ◽

Expansive Agent

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Experimental Study on Deformation Behavior and Compressive Strength of Concrete Cast in Steel Tube Arches under Low-Temperature Conditions

Advances in Materials Science and Engineering ◽

10.1155/2020/8016282 ◽

2020 ◽

Vol 2020 ◽

pp. 1-10

Author(s):

Tuo Shi ◽

Nianchun Deng ◽

Xiao Guo ◽

Wen Xu ◽

Shi Wang

Keyword(s):

Compressive Strength ◽

Low Temperature ◽

Performance Test ◽

Large Diameter ◽

Test Site ◽

Steel Tube ◽

Design Strength ◽

Curing Conditions ◽

Expansive Agent ◽

Arch Bridges

Taking the construction of a concrete-filled steel tube (CFST) arch bridge (part of the Sichuan-Tibet Railway) in low temperatures as the test site, firstly the deformation performance test of concrete was carried out. Following this initial testing, measurement of compressive strength and shrinkage performance was conducted in large-diameter CFSTs under a variety of curing conditions. Experimental results showed that the expansion effect of Ca-Mg composite expansive agent in concrete was better than that of other expansive agents at any stage. Under low-temperature curing (0°C), the sampling strength of the large-diameter CFSTs reached 73.5% of the design strength at 28 d in the presence of a nonthermal curing system. The design strength itself was reached, when a curing system involving a thermal insulation film was applied, and use of this film also led to improvements in concrete shrinkage. The results suggested that a Ca-Mg composite expansive agent, combined with an insulation film curing system, should be the technique selected for concrete pumping construction of CFST arch bridges in Tibet.

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The dynamical behaviour of type-K competitive Kolmogorov systems and its application to three-dimensional type-K competitive Lotka Volterra systems

Nonlinearity ◽

10.1088/0951-7715/16/3/301 ◽

2003 ◽

Vol 16 (3) ◽

pp. 785-801 ◽

Cited By ~ 24

Author(s):

Xing Liang ◽

Jifa Jiang

Keyword(s):

Three Dimensional ◽

Dynamical Behaviour ◽

Type K ◽

Volterra Systems

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An Improved Nickel Based MIMS Thermocouple for High Temperature Gas Turbine Applications

Volume 1: Aircraft Engine; Ceramics; Coal, Biomass and Alternative Fuels; Controls, Diagnostics and Instrumentation ◽

10.1115/gt2012-68464 ◽

2012 ◽

Author(s):

Michele Scervini ◽

Catherine Rae

Keyword(s):

High Temperature ◽

Gas Turbine ◽

High Temperatures ◽

Gas Turbines ◽

Material Science ◽

University Of Cambridge ◽

Type K ◽

Metallurgical Analysis ◽

The University ◽

High Temperature Gas

A new Nickel based thermocouple for high temperature applications in gas turbines has been devised at the Department of Material Science and Metallurgy of the University of Cambridge. This paper describes the new features of the thermocouple, the drift tests on the first prototype and compares the behaviour of the new sensor with conventional mineral insulated metal sheathed Type K thermocouples: the new thermocouple has a significant improvement in terms of drift and temperature capabilities. Metallurgical analysis has been undertaken on selected sections of the thermocouples exposed at high temperatures which rationalises the reduced drift of the new sensor. A second prototype will be tested in follow-on research, from which further improvements in drift and temperature capabilities are expected.

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Mixture Ratio Design of Inorganic Polymer Concrete and the Study of Expansive Performance

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.357-360.1142 ◽

2013 ◽

Vol 357-360 ◽

pp. 1142-1147 ◽

Cited By ~ 1

Author(s):

Li Ming Yu ◽

Zhe An Lu ◽

Xiao Hui Yuan ◽

Hui Guo Chen

Keyword(s):

Volume Growth ◽

Inorganic Polymer ◽

Polymer Concrete ◽

Material Strength ◽

Mixture Ratio ◽

Engineering Research ◽

Expansive Agent ◽

New Material ◽

Dry Shrinkage ◽

Mixture Ratio Design

norganic polymer concrete of a new environment-friendly material has been the hot issue in engineering research so far. For this new material, the main job of the paper includes: we design mixture ratios of inorganic polymer concrete by ourselves, testing the concrete in the age periods of 3, 7, 28 d. The results indicate that this kind of material strength develops mainly in the first 3 d, the strength grows slowly in the later stage; the dry shrinkage of the configured concrete properties are measured, the curve of dry shrinkage shows that the dry shrinkage occurs mainly in the first 14 d and develops slowly in the late; And measure the expansion performance of the concrete member mixed the different categories expansive agent, the results show that the volume growth of mortar specimens to join HCSA expansion agent are obvious; Test results provide a certain basis for the inorganic polymer concrete of micro expansion.

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