部分预应力混凝土环形截面压弯构件延性系数计算

Study on Ductility Factor of Compress-bend Member for Partial Prestressed Concrete with Ring Section

目的建立环形截面部分预应力混凝土高耸结构截面延性系数的精确计算公式,提出延性系数和预应力度的关系.方法根据周边均匀配筋的环形截面的受力特点和平截面假定,应用规范中混凝土和钢筋的常用应力应变关系,进行了环形截面部分预应力压弯构件的承载力和延性系数计算.结果提出了部分预应力压弯构件延性系数的计算公式、建立了延性系数和预应力度的关系曲线,为构件的设计和计算提供了参考.结论通过实例计算可以看出,随着预应力度的增加构件的延性系数降低很快,因此在进行部分预应力构件设计时,延性问题应该引起足够的重视.

In order to make the partial prestressed concrete high-rlse tower structure with ring section meet regular service, the higher prestress degree is applied. Therefore, it is necessary to correctly count ductility factors. According to the character of uniform reinforcement with ring section, the assumption of strains of section keeping in plane and general stress-straln relationship from China concrete code, the formula of ductility factor of partial pre-stressed concrete compress-bending member with ring section are put forward, which can be used as a reference for partial prestressed concrete high-rise tower structure design and the related calculations. Rapid reduction of ductility factor, when pre-stress degree increases, is observed from the example. Hence, ductility should be drawn attention to in the course of design and calculation of member of partial prestressed concrete.