English to Portuguese Tech/Engineering Mining & Minerals / Gems

The shape of the loosening zone becomes an ellipse with its long axis oriented in the direction of major principle stress. this is due to the confining effect of higher stresses. Note that the opposite trend will be observed if the stresses are high enough to cause rockmass failure. In this case the ellipse will be oriented with the long axis perpendicular to the major principle stress
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tensão máxima principal?
Esta é do tempo do Shakespeare. Deve ser de um inglês lá de Stratford-on-Avon...