根据《混规》第 9.3.11 条，第 9.3.12 条
$$
a = 4 0 0 + 3 5 0 - 6 0 0 + 2 0 = 1 7 0 \mathrm{mm} > 0. 3 \times 3 5 0 = 1 0 5 \mathrm{mm}
$$
$$
A _ {\mathrm{sv}} = \frac {F _ {\mathrm{v}} a}{0 . 8 5 f _ {\mathrm{y}} h _ {0}} = \frac {3 0 0 \times 1 0 ^ {3} \times 1 7 0}{0 . 8 5 \times 3 6 0 \times 3 5 0} = 4 7 6. 2 \mathrm{mm} ^ {2}
$$
$$
\rho_ {\mathrm{sv}, \min} = \max \left\{0.2\%, 0.45 \times \frac {1.71}{360} \right\} = \max \left\{0.2\%, 0.214 \% \right\} = 0.214 \%
$$
$$
A _ {\mathrm{sv,min}} = 0.214 \% \times 700 \times 400 = 599.2 \mathrm{mm} ^ {2} > A _ {\mathrm{sv}}
$$
$$
A _ {\mathrm{sh}} = 1. 2 \frac {F _ {\mathrm{h}}}{f _ {\mathrm{y}}} = 1. 2 \times \frac {3 0 \times 1 0 ^ {3}}{3 6 0} = 1 0 0 \mathrm{mm} ^ {2}
$$
$$
A _ {\mathrm{s}} = 5 9 9. 2 + 1 0 0 = 6 9 9. 2 \mathrm{mm} ^ {2}
$$
因此选（C）
