葡萄胎分为_________、_________两类
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Write a telephone message according to the information below.You are working at an office of a school. It is 11 A.M. A call comes in for Kathy. She is teaching a class. It is Mrs. Ross who wants to sign up for summer classes. She wants Kathy to call her before 3 P.M. today at 426-1103.
预应力混凝土构件的控制截面处于消压状态,则( )
A. 控制截面上任意一点混凝土的应力为零
B. 控制截面的抗裂边缘混凝土的应力为零
C. 控制截面上有拉应力的存在
D. 以上说法都不对
先张法预制预应力构件,持久状况正应力验算在计算中采用( )
A. 全截面换算截面
B. 净截面计算
C. 开裂截面
D. 以上都不对
对于预应力混凝土简支梁,在预加应力阶段,梁受到的作用包括()和()