【摘要】 随着预应力混凝土结构的广泛应用,其耐久性问题已经成为普遍关注的研究课题。钢绞线作为无粘结预应力结构的关键材料,研究其锈蚀引起的耐久性问题具有较强的现实意义。本文采用钢绞线加速锈蚀试验,研究无粘结预应力钢绞线锈蚀后的力学性能,分析不同锈蚀程度对钢绞线的名义极限强度、名义屈服强度、名义弹性模量、伸长率的影响,建立锈蚀率与钢绞线名义极限强度、名义屈服强度,名义弹性模量和伸长率之间关系的数学表达式,提出锈蚀钢绞线的应力-应变本构关系。对比普通钢筋锈蚀后的力学性能,研究表明:钢绞线与普通钢筋相比,对锈蚀更为敏感。本文建议在无粘结预应力混凝土结构中更应该关注钢绞线的锈蚀问题。更多还原

【Abstract】 Along with widespread application of prestressed concrete structures the problem of durability has become the research topic subject to general attention.As the key material of the unbonded prestressed structure,the durability quality of steel stranded wires affected by corrosion remains the research subject of stronger practical significance.By the accelerated steel strand corrosion test,the mechanical properties of corroded unbonded prestressed steel stranded wires are studied.The affection of different degrees of corrosion on the nominal ultimate strength,nominal yield strength,nominal elastic modulus and elongation ratio of steel stranded wires are analyzed.The mathematical expression of the relation between the corrosion ratio and the nominal ultimate strength,nominal yield strength,nominal elastic modulus and elongation ratio of steel stranded wires is built.The stress-strain constitutive relation of corroded steel stranded wires is put forward.Compared with the mechanical performance of ordinary corroded steel bars,the steel stranded wires are proved more sensitive to corrosion.This paper suggests to pay close attention to corrosion of steel stranded wires in the unbonded prestressed concrete structures.更多还原