预应力等截面T梁锚固区开裂机理分析及优化

Analysis and Optimization of Cracking Mechanism in Anchorage Zone of Prestressed Uniform-section T-beam

摘要:

随着我国逐步提出绿色低碳高质量发展的前进战略，众多学者提出了等截面T梁的概念，并着重于等截面T梁在抗剪承载能力方面的研究，对由于腹板厚度降低而产生的预应力锚固区裂缝鲜有涉及。为探索等截面T梁在实际应用中，梁端锚固区的应力分布规律，进行了参数化的有限元分析，并提出合理的等截面T梁预应力布置方法和思路。研究表明等截面T梁虽然在支点位置腹板并未加宽，但仍然能够满足国内外对结构抗弯、抗剪承载能力的要求。同时等截面T梁梁端截面会由于预应力张拉产生局部腹板开裂现象，这种现象与梁体截面大小关联性较小，与预应力钢束布置位置有关。

Abstract:

As China gradually advances its green, low-carbon and high-quality development strategy, numerous scholars have proposed the concept of uniform-section T-beams and focused on studying their shear bearing capacity. However, there is little research on cracks in the prestressed anchorage zone caused by reduced web thickness. To explore the stress distribution pattern in the beam end anchorage zone of uniform-section T-beams in practical applications, a parametric finite element analysis is conducted, and a reasonable prestressing arrangement method and approach for uniform-section T-beams are proposed. The research indicates that although the web plate is not widened at the fulcrum position of the uniform-section T-beam, it still meets the domestic and international requirements for structural bending and shear bearing capacity. At the same time, the beam end section of the uniform-section T-beam may experience local web plate cracking due to prestress tensioning. This phenomenon is less related to the size of the beam section and more related to the arrangement position of the prestressed steel tendons.