Freeze–thaw damage and chemical change of a portland cement concrete in the presence of diluted deicers

The SHRP 2 R21 project on composite pavement investigated the durability of various mixtures of portland cement concrete (PCC) used in the construction of a two-layer composite PCC pavement. Project consultants in Europe, where composite PCC over PCC pavement was more common than in the United States, advised the R21 research team to consider using the CIF (capillary suction, internal damage, and freeze–thaw) standard of the International Union of Laboratories and Experts in Construction Materials, Systems, and Structures (RILEM), Paris, rather than the familiar ASTM standards. As a result, the R21 project adopted the RILEM CIF standard to evaluate the freeze–thaw durability and salt scaling resistance of concretes. The research also explored a modified RILEM CIF test (using pure water instead of a sodium chloride solution in scaling tests) alongside the standard RILEM CIF tests. The paper describes this experience to expose other institutions and agencies in the United States to the RILEM standards for the freeze–thaw durability and salt scaling resistance testing of concretes.

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Freeze-Thaw Durability of Portland Cement Concrete Subjected to Aircraft Deicer

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.152-153.1856 ◽

2010 ◽

Vol 152-153 ◽

pp. 1856-1861 ◽

Cited By ~ 1

Author(s):

Hai Yan Ma ◽

Hong Fa Yu ◽

Wen Tao Cao ◽

Kang Bai ◽

Peng Zhou ◽

...

Keyword(s):

Portland Cement ◽

Tap Water ◽

Portland Cement Concrete ◽

Nacl Solution ◽

Cement Concrete ◽

Commercial Aircraft ◽

Freeze Thaw ◽

Negative Effect ◽

Glycol Solution ◽

Durability Of Concrete

Influence of glycol, which is the main composition of the most frequently used aircraft dicer, on the freeze-thaw durability of Portland cement concrete were investigated. Freeze-thaw durability of Portland cement concrete was tested by accelerated freeze-thaw test. Four kinds of solutions, namely tap water, 3.5% NaCl solution, glycol solutions and a LBR-A type commercial aircraft deicer were employed to be the freezing-thawing mediums. Results show that freeze-thaw durability of concrete exposed to glycol solutions is closely related to the solution concentrations. Failure of concretes exposed to 3.5% glycol solution is similar to that of those exposed 3.5% NaCl solution, which are attributed to serious surface scaling. While damage of concrete exposed to 12.5% and 25% glycol solutions are postponed, and the durability of concrete are increased. Compared with glycol solution, the commercial aircraft deicer demonstrated much more negative effect to concrete freeze-thaw durability, and the degree even exceeds 3.5% NaCl solution. Consequently, the commercial aircraft deicer is not a kind of environmental friendly deicer as usually considered.

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Development of a Capacitor Probe to Detect Subsurface Deterioration in Concrete

MRS Proceedings ◽

10.1557/proc-503-231 ◽

1997 ◽

Vol 503 ◽

Cited By ~ 2

Author(s):

B. K. Diefenderfer ◽

I. L. Al-Qadi ◽

J. J. Yoho ◽

S. M. Riad ◽

A. Loulizi

Keyword(s):

Dielectric Constant ◽

Portland Cement ◽

Electromagnetic Waves ◽

Low Cost ◽

Complex Dielectric Constant ◽

Life Cycle Costs ◽

Parallel Plates ◽

Portland Cement Concrete ◽

Cement Concrete ◽

Set Up

ABSTRACTPortland cement concrete (PCC) structures deteriorate with age and need to be maintained or replaced. Early detection of deterioration in PCC (e.g., alkali-silica reaction, freeze/thaw damage, or chloride presence) can lead to significant reductions in maintenance costs. However, it is often too late to perform low-cost preventative maintenance by the time deterioration becomes evident. By developing techniques that would enable civil engineers to evaluate PCC structures and detect deterioration at early stages (without causing further damage), optimization of life-cycle costs of the constructed facility and minimization of disturbance to the facility users can be achieved.Nondestructive evaluation (NDE) methods are potentially one of the most useful techniques ever developed for assessing constructed facilities. They are noninvasive and can be performed rapidly. Portland cement concrete can be nondestructively evaluated by electrically characterizing its complex dielectric constant. The real part of the dielectric constant depicts the velocity of electromagnetic waves in PCC. The imaginary part, termed the “loss factor,” describes the conductivity of PCC and the attenuation of electromagnetic waves.Dielectric properties of PCC have been investigated in a laboratory setting using a parallel plate capacitor operating in the frequency range of 0.1 to 40.1MIHz. This capacitor set-up consists of two horizontal-parallel plates with an adjustable separation for insertion of a dielectric specimen (PCC). While useful in research, this approach is not practical for field implementation. A new capacitor probe has been developed which consists of two plates, located within the same horizontal plane, for placement upon the specimen to be tested. Preliminary results show that this technique is feasible and results are promising; further testing and evaluation is currently underway.

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