先张法的预压指的是张拉预应力钢筋至最大控制应力并加以锚固的时刻。
查看答案
后张法的预压指的是放松预应力钢筋的时刻.
A. 对
B. 错
There are many ___ jewels in the museum.
A. valued
B. invaluable
C. valueless
D. worthy
The rising crime rate is ___ major concern of ___ society.
A.the, the
B.a, \
C.a, the
D.\, the
You see the lighting ___ it happens, but you hear the thunder later.
A.the instant
B.on the instant
C.for an instant
D.in an instant
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