预应力混凝土连续梁抗剪强度研究

Study of shearing strength of P.C. continuous beams

现行《公路桥涵设计规范》（ Ｊ Ｔ Ｊ０２３８５）［１］ 尚缺乏预应力混凝土连续梁抗剪强度的计算公式，且国内外对此也很少研究，无经验可援。在对钢筋混凝土简支梁［２］ 、连续梁［３］和预应力混凝土简支梁［４］抗剪强度研究的基础上，建立了按承载能力极限状态计算预应力混凝土连续梁抗剪强度的公式和构造要求；并通过４ 根较大尺寸（ｌ＝ ５ｍ ＋ ５ｍ ）的等高度和变高度预应力混凝土连续梁的试验梁验证，证明所建议的计算公式和构造要求是安全、适用的；计算模式和现行《公路桥涵设计规范》一致，因此应用也很方便。

There is still no shear formula in calculating the P.C continuous beams in the present 'Design Code for Highway Bridges and Culverts' (JTJ 023 85). In this paper, the formula of shearing strength in limit state, design method and construction provisions for such beams are proposed. Furthermore four larger size models of P.C.continuous beams (l=5m+5m) with constant depth and variable depth are investigated. The experimental results show that the design method and computation formula proposed by the authors can give acceptable results on the safe side.