进行水泥胶砂强度试验时,当其某个试件强度值超出平均强度值的()时,应剔除后再取平均值。 ["10%","15%","20%","25%"]
为防止脚手架的内倒外倾,加强立杆的纵向刚度必须规定设置()。 ["A、十字撑","B、扫地杆","C、联墙体","D、斜撑"]
1atm(标准大气压)=()kPa1mmHg(毫米汞柱)=()Pa(帕) ["101325,101.325","101.325,101325","101.325,133.332","1.01325,133.332"]
()石油中含量最多的元素是。 ["A、碳","B、氢","C、氧"]
普通水泥强度等级分为()。 ["32.5","32.5R","62.5","62.5R","42.5、42.5R","52.5、52.5R"]
焊补时发生爆炸火灾的原因有那些?