The Effect of Crumb Rubber on Freeze-Thaw Durability of Portland Cement Concrete

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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Influence of Crumb-Rubber in the Mechanical Response of Modified Portland Cement Concrete

Advances in Civil Engineering ◽

10.1155/2017/3040818 ◽

2017 ◽

Vol 2017 ◽

pp. 1-9

Author(s):

J. Retama ◽

A. G. Ayala

Keyword(s):

Mechanical Properties ◽

Portland Cement ◽

Damage Evolution ◽

Mechanical Response ◽

Numerical Models ◽

Experimental Tests ◽

Crumb Rubber ◽

Portland Cement Concrete ◽

Cement Concrete ◽

Main Hypothesis

The influence of crumb-rubber on the mechanical properties of Portland cement concrete (PCC) is studied by experimental tests and numerical simulations. The main hypothesis of the study is that replacing part of the stone aggregate with crumb-rubber in the mix modifies the energy dissipation during the cracking process and affects the concrete behaviour under monotonically increasing loads. The experimental research program characterizes the mechanical properties of PCC for three different types of concrete with a variable content of crumb-rubber. The experimental results showed that fracture energy and other properties are directly related to the rubber fineness used in the mixture. The material properties derived for these laboratory tests are used to study, by numerical models, its response through its damage evolution. The numerical model used to simulate the damage evolution of the concrete is the Embedded Discontinuity Method (EDM). One characteristic of the EDM is that it does not need to modify the mesh topology to propagate the damage through the continuum solid. For this study, the Disk-Shaped Compact Tension specimen geometry, normed by the D7313-13 of the ASTM, is used. Results showed that the numerical methods provide good approximation of the experimental curve in the elastic and softening branches.

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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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