$$
V = 0. 8 F, N = 0. 6 F (\text {拉})
$$
根据《混规》第9.7.2条
$$
\alpha_ {\mathrm{b}} = 1. 0, \quad \alpha_ {\mathrm{r}} = 0. 8 5
$$
$$
A _ {\mathrm{s}} \geqslant \frac {V}{\alpha_ {\mathrm{r}} \alpha_ {\mathrm{v}} f _ {\mathrm{y}}} + \frac {N}{0 . 8 \alpha_ {\mathrm{b}} f _ {\mathrm{y}}} + \frac {M}{1 . 3 \alpha_ {\mathrm{r}} \alpha_ {\mathrm{b}} f _ {\mathrm{y}} z}
$$
$$
2 0 1 \times 8 = \frac {0 . 8 F}{0 . 8 5 \times 0 . 6 8 6 \times 3 0 0} + \frac {0 . 6 F}{0 . 8 \times 1 . 0 \times 3 0 0} \Rightarrow F = 2 2 7 \mathrm{kN}
$$
$$
A _ {\mathrm{s}} \geqslant \frac {N}{0 . 8 \alpha_ {\mathrm{b}} f _ {\mathrm{y}}} + \frac {M}{0 . 4 \alpha_ {\mathrm{r}} \alpha_ {\mathrm{b}} f _ {\mathrm{y}} z}
$$
$$
2 0 1 \times 8 = \frac {0 . 6 F}{0 . 8 \times 1 . 0 \times 3 0 0} \Rightarrow F = 6 4 3 \mathrm{kN}
$$
二者取小
因此选（C）
