传力杆参数对杆周混凝土力学响应的影响

Influence of Dowel Parameters on Mechanical Response of Concrete Around Dowel Bars

建立三维有限元实体模型,将混凝土-传力杆摩擦系数、传力杆直径、传力杆布设间距、面板厚度作为影响因子,采用单因子轮换法,分析传力杆杆周混凝土力学响应的变化规律.结果表明,随着混凝土-传力杆摩擦系数的增大,最大水平拉应力显著减小,而竖向拉应力不降反增,故存在合理的界面摩擦系数;在传力杆直径从28 mm增加到36 mm过程中,界面应力水平下降幅度较大;随着传力杆布设间距的增大,界面应力不断增长,且增长速度随着间距的增加而增加;增加面板的厚度,会少量降低杆周围混凝土的各应力水平.

Establishing the three-dimensional finite element model, the concretedowel friction coefficient, dowel diameter, dowel bar spacing and slab thickness were taken as the impact factors. The single-factor rotation method was used to analyze the variation of the mechanical response of the concrete around dowel bar. The results showed that with the increase of the concrete-dowel friction coefficient, the maximum horizontal tensile stress is significantly reduced, while the vertical tensile stress does not decrease, so there is a reasonable interfacial friction coefficient. When the dowel diameter increases from 28 mm to 36 mm, the interface stress level decreases greatly. With the increase of the dowel bar spacing, the interface stress increases, and the growth rate increases with the increase of the spacing. The increase of slab thickness reduces the stress level of concrete around dowel bar slightly.