预应力型钢混凝土梁结构设计与研究

Structural design and research of prestressed steel reinforced concrete beam

采用预应力技术改善大跨度型钢混凝土梁正常使用性能,从而形成新型的预应力型钢混凝土梁(PSRCB)组合结构。文章基于大跨度框架梁结构设计,对型钢混凝土梁与预应力型钢混凝土梁结构方案进行了对比研究,采用非线性有限元分析考察了预应力型钢混凝土梁的受力机理和结构设计的可靠性。结果表明:大跨度型钢混凝土梁的配筋由正常使用性能(如最大裂缝宽度)控制,采用预应力型钢混凝土梁更加经济合理;预应力型钢混凝土框架梁内置型钢减小了开裂后刚度的变化量,材料强度得到充分发挥;适度增加型钢混凝土梁预应力度可以减小的梁跨中挠度,降低钢筋及型钢受拉应力,改善其正常使用性能。

Prestressed steel reinforced concrete（ PSRC）beam is a new type prestressed composite beam which uses prestressing technology in SRC beam to improve its serviceable performance. The comparison between PSRC beam and SRC beam was conducted to point out the advantages and disadvantages of each structure scheme. The bearing mechanism and the reliability of structural design for PSRC beam we are analyzed by three-dimensional nonlinear finite element method. Research indicates that,the serviceable performance（such as maximum crack width）of large span SRC beam is difficult to control and the use of prestressing technology in SRC beam is economical and reasonable;the rigidity of PSRC beam decreases more slowly after crack due to the H-tape steel;the strength of material is fully utilized;the deflection and stress of tensile rebar and H-tape steel are reduced by improving the prestressing degree of PSRC beam.