超高性能纤维混凝土在公路桥梁加固中的应用分析

Application Analysis of Ultra-high Performance Fiber Reinforced Concrete in Highway Bridge Reinforcement

针对传统梁桥加固技术易影响桥梁耐久性的问题,提出将钢纤维混凝土材料应用于主梁和桥面铺装层,提高桥面抵抗梁端变形程度,减少应力集中现象。分析了不同钢纤维加铺层厚度,加铺层长度下路面结构的应力状态,为桥面铺装层的设计提供合理建议,研究结果表明:当钢纤维混凝土铺装长度和厚度一定时,随着跨径增加,钢纤维铺装横截面拉应力逐渐增加;当厚度和跨径一定时,随着加铺层长度增加,铺装横截面拉应力下降,最终趋于平稳;根据T型简支梁结构,考虑安全性能和经济性价比,确定钢纤维混凝土跨径为10-15 m时,加铺层长度取值为50 cm,厚度取值为8-12 cm;跨径为20-25 m时,加铺层长度取值为75 cm,加铺层厚度8-12 cm;跨径为30 m时,加铺层长度取值为100 cm,厚度取值为8-12 cm。

Aiming at the problem that the traditional beam bridge reinforcement technology is easy to affect the durability of the bridge. It is proposed that the steel fiber reinforced concrete material should be applied to the main beam and bridge deck pavement to improve the resistance of the bridge deck to the deformation of the beam end and to reduce the stress concentration phenomenon. The stress state of pavement structure under different thickness and length of steel fiber overlay is analyzed, which provides reasonable suggestions for the design of bridge deck pavement. The results show that when the pavement length and thickness of steel fiber reinforced concrete are constant, the tensile stress of cross section of steel fiber reinforced concrete increases gradually with the increase of span, and when the thickness and span are constant, the tensile stress of cross section of pavement decreases with the increase of overlay length, and finally tends to tend to. According to the T-shaped simply supported beam structure, considering the safety performance and economy point of view, When the span of steel fiber reinforced concrete is 10~15 m, the length and thickness of the overlay layer are 50 cm and 8~12 cm, and when the span is 20~25 m, the length of the overlay layer is 75 cm and the thickness of the overlay layer is 8~12 cm. When the span is 30 m, the length and thickness of the overlay layer are 100 cm and 8~12 cm, respectively.