一种无腹筋混凝土梁受剪承载力计算的新方法

发布时间：2018-03-19 08:15

本文选题：钢筋混凝土梁　切入点：受剪承载力　出处：《东南大学学报(自然科学版)》2017年02期 　论文类型：期刊论文

【摘要】：为了提高无腹筋混凝土梁特别是大尺寸、低纵筋率的无腹筋梁的受剪承载力预测精度,提出了一种无腹筋混凝土梁受剪承载力计算的新方法.首先,假定剪力主要由无腹筋梁的混凝土受压区承担,并根据其破坏模式将混凝土受压区细分为剪压区和斜拉区2个部分;其次,通过分析剪压区和斜拉区的破坏机理,建立抗剪贡献的计算公式;然后,通过合理简化和理论推导,确定受压区高度、剪压区高度等主要参数的取值;最后,在考虑尺寸效应的基础上,建立无腹筋混凝土浅梁的受剪承载力解析公式,该公式具有明确的物理涵义,能够反映混凝土强度、纵筋率、剪跨比以及尺寸效应等主要因素的影响.试验结果表明,相比于现行主要规范公式,所提公式的预测精度和预测稳定性均有明显提高.
[Abstract]:In order to improve the prediction accuracy of shear capacity of concrete beams without web reinforcement, especially those with large size and low longitudinal reinforcement ratio, a new method for calculating the shear capacity of concrete beams without web reinforcement is proposed. It is assumed that the shear force is mainly borne by the concrete compression zone without web reinforcement, and according to its failure mode, the concrete compression zone is subdivided into shear-compression zone and cable-stayed zone. Secondly, the failure mechanism of shear-compression zone and inclined tension zone is analyzed. Then, through reasonable simplification and theoretical derivation, the values of the main parameters such as the height of the compression zone and the height of the shear zone are determined. Finally, on the basis of considering the size effect, An analytical formula for shear bearing capacity of concrete shallow beams without web reinforcement is established. The formula has a clear physical meaning and can reflect the influence of the main factors such as concrete strength, longitudinal reinforcement ratio, shear span ratio and size effect. Compared with the current main standard formulas, the prediction accuracy and prediction stability of the proposed formula are obviously improved.
【作者单位】：东南大学混凝土与预应力混凝土结构教育部重点实验室;中铁大桥勘测设计院集团有限公司;
【基金】：交通运输部建设科技资助项目(2014318494020) 江苏省交通运输科技资助项目(2014Y01)
【分类号】：TU375.1

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