某一钢丝绳的破断拉力为300kN,用作载人时,其最大允许拉力为()。A. 37.5kNB. 60kNC. 25kND. 85.7kN

作者: rantiku 人气: - 评论: 0
问题 某一钢丝绳的破断拉力为300kN,用作载人时,其最大允许拉力为()。
选项 A. 37.5kN B. 60kN C. 25kN D. 85.7kN
答案 C
解析 本题考查的是钢丝绳。钢丝绳许用拉力=钢丝绳破断拉力/安全系数。如果用于载人,则安全系数不小于12~14.300/12=25;300/14=21.4.所以答案应该在21.4和25区间。

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