【摘要】 为明确新版《建筑结构可靠性设计统一标准》(GB 50068-2018)中的荷载分项系数调整对钢筋混凝土梁设计安全性的影响，参考已有统计参数模型，采用蒙特卡罗法对钢筋混凝土梁进行可靠指标计算。考虑抗弯和抗剪两种破坏模式、四种常用荷载组合等情形，分别计算了荷载分项系数调整后钢筋混凝土梁可靠指标的变化。结果表明：荷载分项系数调整后，对于办公楼活荷载、风荷载、雪荷载分别与恒载组合以及办公楼活荷载和风荷载与恒载联合组合的四种情况，钢筋混凝土梁的抗弯可靠指标提高了约9.7%～16.9%,基本满足目标可靠指标3.2的要求；当抗力分项系数在1.5～2.2范围变化时，钢筋混凝土梁的抗剪可靠指标增加较小，增幅仅约为0.05～0.20;当抗力分项系数取2.2时，钢筋混凝土梁的抗剪可靠指标基本满足目标可靠指标3.7的要求。更多还原

【Abstract】 In order to clarify the influence of load partial factors adjustment on the design safety of reinforced concrete beams in the new edition of Unified Standard for Reliability Design of Building Structures(GB50068-2018), the Monte Carlo method is used to calculate the reliability index of reinforced concrete beams by referring to the existing statistical parameter model. Considering flexural and shear failure modes and four common load combinations, the variation ranges of the reliability indexes of reinforced concrete beams after adjusting the load partial factors are calculated respectively. The results show that the bending reliability index of reinforced concrete beams increases by 9.7%～16.9% for the combination of live load, wind load, snow load and dead load of office buildings, and the combination of live load and wind load and dead load of office buildings, basically meeting the requirement of the target reliability index 3.2; when the partial factor for resistance varies from 1.5～2.2, the shear reliability index of reinforced concrete beams increases slightly, only about 0.05～0.20; when the partial factor for resistance is 2.2, the shear reliability index of reinforced concrete beam basically meets the requirement of target reliability index 3.7.更多还原