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Transcripción del abstract original del autor: Continued growth in the need to transport large quantities of natural gas over long distances has focused attention on reducing the installed cost of long-distance high-capacity pipelines. One of the more attractive ways by which this can be achieved is to utilise higher strength steels. Grade X80 is now established as a fully satisfactory material technology in many parts of the world, and preproduction grade X100 pipes have been extensively evaluated during recent years, adding confidence to the use of X100 for future generation highly rated applications. Higher strength grades are in the development stage. Fracture control plans are an essential pre-requisite for safe design and operation. The designer must take measures to assess and control the likelihood of a fracture occurring and mitigate or limit the consequences if it should occur. Issues include both crack initiation and propagation in the parent pipe material, the seam and girth welds. High strength steels tend to have an inherently higher ratio of yield strength to tensile strength, combined with a lower capacity for absorbing and redistributing local plastic strain, compared to lower strength steels. Recent experimental work and analytical advances addressing these issues in the context of the fracture control plan are reviewed and evaluated in the paper to demonstrate how a sound approach to fracture control is being developed for next generation pipelines utilising high strength steels.