A student wants to measure the strain at a particular point K on a loaded specimen, so she affixes a 45° strain rosette at point K and obtains the following results: €A = 390 μrad €B = 275 μrad Ec = 325 μrad After packing up and going home to analyse her results, she realises that the strain rosette was misaligned by 0 degrees CW (where a negative corresponds to CCW) from the x-y axes-ie. Gauge C is not parallel with the x-axis and is instead parallel with a different x' axis that is rotated by 0 degrees-where: 0 = 16 deg Instead of replacing the rosette and retaking measurements, the student realises she can use what she learned in ENGG2400 to find the strains she's interested in. 45° 45° a) Draw a diagram of the situation, showing both the x-y axes and the strain rosette. b) Calculate Exx, Eyy and Yxy. c) Calculate the maximum in-plane shear strain and the associated average normal strain. K X

A student wants to measure the strain at a particular point K on a loaded specimen, so she affixes a 45° strain rosette at point K and obtains the following results: €A = 390 μrad €B = 275 μrad Ec = 325 μrad After packing up and going home to analyse her results, she realises that the strain rosette was misaligned by 0 degrees CW (where a negative corresponds to CCW) from the x-y axes-ie. Gauge C is not parallel with the x-axis and is instead parallel with a different x' axis that is rotated by 0 degrees-where: 0 = 16 deg Instead of replacing the rosette and retaking measurements, the student realises she can use what she learned in ENGG2400 to find the strains she's interested in. 45° 45° a) Draw a diagram of the situation, showing both the x-y axes and the strain rosette. b) Calculate Exx, Eyy and Yxy. c) Calculate the maximum in-plane shear strain and the associated average normal strain. K X

Materials Science And Engineering Properties

1st Edition

ISBN:9781111988609

Author:Charles Gilmore

Publisher:Charles Gilmore

Chapter6: Introduction To Mechanical Properties

Section: Chapter Questions

Problem 6.9P

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