Structural damage

Pollution is defined as the introduction by man into the environment of substances liable to cause hazards to human health, harm living resources and ecological systems, damage structure or amenity, or interfere with legitimate use of the environment. This all-embracing definition includes the impact of polymers on the environment, both in their original form as raw materials. 

There is an enzymatic mechanism of DNA damage repair, which is responsible for recognition, discharge, and replacement of damaging structures with normal ones. On the other hand, carbon radicals formed on the DNA backbone can be repaired by the interaction with antioxidants. Practically all traditional antioxidants and free radical scavengers have been described to inhibit free radical-mediated DNA damage. 

Insulators or materials with low heat conduction are often used for fire protection coatings and thermal insulation. This thermal barrier prevents heat reaching and damaging structural steel and process vessels. 

Dismantling operations will create materials that are heavy and unwieldy. Handling heavy objects will create a risk of damaging structures and equipment still in operation or intended for abandonment in place. Workers could also incur risks. The placement and use of lifting equipment must be carefully planned to minimize the possibility of boom overload, collision of a boom or load with fixed objects, and contact with energized electrical distribution lines. 

In the aerospace market a distinction is made between primary and secondary structural applications. Joint failure in a primary structure will result in the loss of the aircraft, whereas failure in a secondary structure will result in only localized damage. Structural adhesives are used in both applications. Figure 1.4 illustrates the degree to which adhesive bonding is used in modem aircraft. 

Electron microscopy is one of the most powerful methods for studying the damage structure of irradiated materials. Its limitation lies in the observable size of the de-... 

Chromosome damage (structural and some indication of potential numerical damage, e.g., polyploidy). 

Fibre-reinforced polymers (FRP) rebars, usually made of an epoxy matrix reinforced with carbon or aramide fibres, have also been proposed both as prestressing wires and reinforcement. Nevertheless, they are not discussed here, because these applications are still in the experimental phase and there is a lack of experience on their durability. In fact, while they are not affected by electrochemical corrosion typical of metals, they are not immune to other types of degradation. FRP are also used in the form of laminates or sheets as externally bonded reinforcement in the rehabilitation of damaged structures this application will be addressed in Chapter 19. 

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