混凝土强度对钢筋混凝土桥面板抗冲切性能的影响

Influence of concrete strength on punching shear resistance performance of reinforced concrete bridge deck

为研究不同混凝土强度对钢筋混凝土桥面板抗冲切性能的影响,在试验基础上建立不同混凝土强度的钢筋混凝土桥面板数值计算模型。在验证数值计算模型正确的基础上,采用数值模拟方法分别对钢筋混凝土桥面板混凝土损伤、应力分布、极限承载力及其变化趋势进行分析。结果表明,混凝土强度对钢筋混凝土桥面板弹性模量、延性等性能均有不同程度的影响。以中国规范GB 50010—2010抗冲切承载力计算公式为基础,采用回归方法,拟合得到适用混凝土强度为C15~C80的抗冲切极限承载力公式。为验证提出公式的可靠性,通过对比国内外学者试验数据与各抗冲切承载力公式计算值,认为该公式无论在混凝土强度较低还是及较高时,均能较为准确预测钢筋混凝土桥面板极限承载力。

In order to study the influence of different concrete strength on punching shear resistance performance of reinforced concrete bridge deck, numerical calculation models of reinforced concrete bridge deck with different concrete strength grades based on the test were established. Based on verifying the correctness of the numerical calculation model, the method of numerical simulation was used to analyze the concrete damage, stress distribution, ultimate bearing capacity and its change trend of the reinforced concrete bridge deck. The results show that the concrete strength has different influence on the elastic modulus and ductility of reinforced concrete bridge deck. Based on the calculation formula for punching shear resistance bearing capacity of Chinese code GB 50010—2010, the formula for punching shear resistance bearing capacity suitable for concrete strength grades of C15~C80 was obtained by regression method. To verify the reliability of the proposed formula, by comparing the experimental data of scholars at home and abroad with the calculated values of the punching shear resistance bearing capacity formulas, it is believed that this formula can more accurately predict the ultimate bearing capacity of reinforced concrete bridge deck no matter when the concrete strength is low or high.