体外无粘结预应力结构技术的探讨

Discussion on External Unbonded Prestress Structure Technology

体外预应力是后张预应力体系的一个重要分支。在进行体外预应力结构设计时,基本上以无粘结预应力设计为蓝本,没有充分考虑应力增量及二次效应的影响。针对现有的体外预应力混凝土结构设计存在的局限性,结合相关规范及国内外的研究成果,对体外预应力结构设计时应考虑的一些问题进行了探讨,包括体外预应力筋应力增量的取值、钢筋混凝土梁极限应力及抗弯承载力的的计算方法等。

External prestress is an important branch in the post-tensioned prestress. During the external prestress structure designing, the unbonded prestress design is usually taken as an blueprint, the stress increment and the domino effect is not fully considered. According to the limit of current external prestress concrete structure design, based on standards and the search achievement at home and aboard, the discussion is made on some problems should be considered in the external prestress structure design, including the value of external prestress and prestress increment, calculation method of the steel concrete beam limit prestress and flexural capacity.