A.35° B.50° C.65° D.80°
A.施加預(yù)應(yīng)力宜采用一端張拉工藝 B.臺座應(yīng)有足夠的強(qiáng)度、剛度和穩(wěn)定性 C.在澆筑混凝土前,發(fā)生斷裂或滑脫的預(yù)應(yīng)力筋必須予以更換 D.預(yù)應(yīng)力筋放張時,當(dāng)無設(shè)計要求時,不應(yīng)低于設(shè)計的混凝土立方體抗壓強(qiáng)度標(biāo)準(zhǔn)值的70%