A.CC%≤33.3% B.CC%>33.3% C.CC%<35.5% D.CC%>35.5%
A.卷邊發(fā)現(xiàn)有小孔或損壞 B.卷邊背彎試驗發(fā)生開裂 C.卷邊背彎試驗出現(xiàn)裂縫 D.ABC均是
A.300 B.250 C.200 D.500