A.4.5m B.9m C.6m D.7.2m
A.嵌水泥砂漿 B.立磚斜側(cè) C.半磚順砌 D.澆細(xì)石混凝土
A.≤2h且≤1000mm B.≤4h且≤1500mm C.≥2h且≥1000mm D.≥4h且≥1500mm