Buildings and civil engineering works. Sealants. Durability to extension compression cycling under accelerated weathering

In civil engineering, the long-term service life of buildings as environmental measures is one of important performances being comparable to structure and fire safety, and it is demanded to improve durability of materials in building construction. This improvement of material durability is highly associating with lifetime of building, and so as not to reach the limit state of building components. It is imperative to determine a specific means and method in order to identify the surrounding environment on the deteriorating effect for building components and materials, as well as predicting a process of degradation phenomena and the limit state of buildings. As part of building materials, polymeric materials become widespread in civil engineering because of taking advantage of excellent property, such as lightweight, high corrosion resistance, and good formability. However, we should look ahead the lifecycle cost in order to have effective application of this material, so it is necessary to understand the lifecycle of such material. In weathering, outdoor weathering test is the surest way to clarify exactly how a material, component, or products degrade by environmental stresses in an acceptable timeframe, but it usually takes few years to decades to obtain a useful or referable result. Meanwhile, accelerated weathering test methods have been proposed as a method to obtain the results in a short period of time than outdoor weathering test. However, the method of estimating a material durability in the actual environment from these obtained data has not yet been established.In this section, it would be showing some attentions for comparison of the results from outdoor and accelerated weathering test. Then the need for investigating weatherability of polymeric materials through physicochemical analysis are emphasized to improve the relevance and precision of durability under field and laboratory weathering test. Lastly, introducing the design of accelerated weathering method based on natural weathering characteristics.

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Durability of Composite Reinforcement for Timber Bridges

Transportation Research Record Journal of the Transportation Research Board ◽

10.3141/1696-54 ◽

2000 ◽

Vol 1696 (1) ◽

pp. 131-135 ◽

Cited By ~ 9

Author(s):

Eoin P. Battles ◽

Habib J. Dagher ◽

Beckry Abdel-Magid

Keyword(s):

Mechanical Properties ◽

Civil Engineering ◽

Synergistic Effects ◽

Physical And Mechanical Properties ◽

Organic Matrix ◽

Void Content ◽

Accelerated Weathering ◽

Durability Test ◽

California Department ◽

Environmental Conditioning

Fiber-reinforced polymeric (FRP) composites are materials that are increasing in use in civil engineering applications. Despite the excellent mechanical properties and corrosion resistance offered by these organic matrix materials, their susceptibility to the synergistic effects of stress and environmental weathering hinders their widespread acceptance in civil engineering. The durability of a specific formulation of wood-compatible, pultruded, E-glass–phenolic composite is characterized. This composite is unique because its layered structure and void content make it compatible with standard structural wood adhesives. The durability of this wood-compatible FRP reinforcement cannot be directly determined from published work on the durability of E-glass composites because of its unique design. A durability test matrix was generated according to specifications and test standards from the International Conference of Building Officials Evaluation Service, Inc., and from the California Department of Transportation. Physical and mechanical properties that were used as indicators of degradation mechanisms and that applied to the bridge environment included tensile behavior, interlaminar shear strength, void content, and glass-transition temperature. Environmental testing involved exposure to various storage media, such as moisture, saline solutions, and calcium carbonate, followed by mechanical testing. Other exposure treatments included dry heat, cyclic freeze-thaw, accelerated weathering, and natural weathering. In addition to the strength-retention determination after environmental conditioning, control and exposed specimens were examined visually with optical and scanning electron microscopy to determine surface changes and their effect on failure and fracture modes.

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