根据《桩规》第 5.3.8 条
$$
h _ {\mathrm{b}} / d _ {1} = 4. 5 / 0. 2 1 = 2 1. 4 3 > 5, \quad \lambda_ {\mathrm{p}} = 0. 8
$$
$$
A _ {\mathrm{j}} = \frac {\pi}{4} \left(d ^ {2} - d _ {1} ^ {2}\right) = \frac {1}{4} \times 3. 1 4 \times \left(4 0 0 ^ {2} - 2 1 0 ^ {2}\right) \times 1 0 ^ {- 6} = 0. 0 9 0 9 8 \mathrm{m} ^ {2}
$$
$$
A _ {\mathrm{pl}} = \frac {\pi}{4} d _ {1} ^ {2} = \frac {3 . 1 4}{4} \times 2 1 0 ^ {2} \times 1 0 ^ {- 6} = 0. 0 3 4 6 2 \mathrm{m} ^ {2}
$$
$$
Q _ {\mathrm{uk}} = Q _ {\mathrm{sk}} + Q _ {\mathrm{pk}} = u \Sigma q _ {\mathrm{sik}} l _ {\mathrm{i}} + q _ {\mathrm{pk}} \left(A _ {\mathrm{j}} + \lambda_ {\mathrm{p}} A _ {\mathrm{pl}}\right)
$$
$$
= 3. 1 4 \times 0. 4 \times (2. 5 \times 4 0 + 3 0 \times 1 2 + 8 \times 4 0 + 8 5 \times 4. 5) + 5 0 0 0 \times (0. 0 9 0 9 8 + 0. 8 \times 0. 0 3 4 6 2) = 2 0 5 3 \mathrm{kN}
$$
