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Question 26.12: Investigate the strength of the laminate of P.26.11 if it is......

Investigate the strength of the laminate of P.26.11 if it is subjected to a compressive load intensity of -100 N/mm. The strength criteria are the same as those of P.26.11.

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From S.26.11,

\sigma_l=-90.4 N / mm ^2  (the load is now compressive)

\begin{aligned}& \sigma_{ t }=-93.4 N / mm ^2 \\& \tau_{ lt }=105 N / mm ^2\end{aligned}

Then

\begin{aligned}& \sigma_1 / X_{ C }=90.4 /1000=0.09 \\& \sigma_{ t } / Y_{ C }=93.4 / 200=0.47 \\& \tau_{ lt}=105 / 70=1.5\end{aligned}

Therefore the plies fail in shear only.

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