A.10 B.20 C.25 D.30
A.主壓應(yīng)力過大 B.預(yù)應(yīng)力鋼筋端部錨固應(yīng)力集中 C.預(yù)應(yīng)力構(gòu)件厚度不足 D.主拉應(yīng)力過大
A.5 B.10 C.15 D.20