后张预制梁终张拉和先张预制梁放张后应实测梁体弹性上拱,实测上拱值不宜大于()倍设计计算值。
A.1.2
B.1.1
C.1.05
参考答案:C
Yesterday my brother __________to say "Happy Birthday" to me from Spain.
A.calls
B.called
C.is calling
D.was calling
用心轴装夹车削套类工件,如果心轴本身同轴度超差,车出的工件会产生尺寸精度误差。()