【摘要】 我国现行设计规范中钢筋混凝土框架中节点抗剪强度计算为半经验半理论计算公式,由于试验数据的有限性和钢筋混凝土材料的离散性,规范建议公式缺乏明确的理论模型。该文以贝叶斯动态信息更新思路,根据主观经验信息选定先验模型,将国内外已完成101组钢筋混凝土框架中节点试件的试验结果作为数据库,应用贝叶斯参数估计方法综合两类信息进行推断,建立了基于贝叶斯理论的多元线性钢筋混凝土中节点抗剪强度概率模型,进而采用贝叶斯后验模型参数剔除理论,剔除影响节点抗剪强度的次要因素,对概率模型进行动态更新,得到中节点抗剪强度简化模型,并将抗剪模型计算值与试验值和美国ACI 352R-02中钢筋混凝土节点抗剪强度的计算公式进行了对比。研究表明:贝叶斯方法继承了先验信息的完备性和大量试验数据的准确性,建议的中节点贝叶斯概率抗剪模型与试验值吻合良好,且较规范值能够更准确地预测钢筋混凝土中节点抗剪强度,可用于该类节点的抗剪强度计算。更多还原

【Abstract】 The current codes for calculating the shear capacity of internal reinforced concrete frame joints are simi-empirical and semi-theoretical. Due to limited test data and the discretized characteristics of concrete structures, the design equations recommended in the code is lack of a clear theoretical framework. Thusly, the concept of dynamic information updates based on the Bayesian approach was introduced. 101 groups of experimental test results of internal frame joints were collected from experience at home and abroad. A multivariate linear probabilistic shear strength model for reinforced concrete internal joints was established using the Bayesian estimation method. Subsequently, the model was simplified using the stepwise procedure to remove parameter insignificant explanatory terms. The developed probabilistic model is compared with experimental results and design equations proposed by ACI 352R-02. It indicated that the proposed model inherits the completeness of prior models and the accuracy of experimental data information, and therefore is recommended for the shear strength calculation of the interior joints of reinforced concrete frames.更多还原