中国铁道科学2025，Vol.46Issue(3)：42-51,10.DOI:10.3969/j.issn.1001-4632.2025.03.05
基于可靠指标负偏调控的路基边坡分项系数标定
Partial Factor Calibration of Subgrade Slopes Considering the Adverse Deviation of Reliability Index
摘要
Abstract
Aiming at the issues regarding stability analysis of railway subgrade soil slopes,an improved partial factor calibration method is proposed,which overcomes the difficulty of the traditional method in controlling adverse negative deviations between the actual reliability index and the target reliability index of slopes.First,the partial factors for subgrade slopes are calibrated by the traditional method.Distribution characteristics of negative deviations between the actual reliability index and the target reliability index of slopes under the limit state are analyzed,and an improved partial factor calibration method is proposed based on negative deviation limitation and residual reduction principles.Second,for subgrade slopes,calibration method is used to determine the target reliability index,applying the improved method to calibrate the partial factors of embankment and cutting slopes.Finally,aiming at the limitation of low engineering usability of the partial factor method caused by the inconsistency of partial factors between embankment and cutting slopes,a unified partial factor determination method is proposed.The research shows that:using traditionally calibrated factors,20%-33%of slopes exhibit hazardous reliability deficits by 0.5 or more relative to the target index.The proposed principle of negative deviation limitation can effectively control the negative deviation between the actual reliability index of the slope and the target value within the allowable range.For common railway scenarios with small-to-medium soil variability,target reliability index of the slope calibrated is approximately 2.2 when the limit state of the slope stability coefficient is between 1.15 to 1.25.Correspondingly,in the limit state expression of the subgrade slope,the partial factors of the cohesion,internal friction angle,and the resistance component of the train load are 1.25,1.20,and 1.05,respectively;and the partial factors of the soil weight and the downslope force component of the train load are 1.03 and 1.05,respectively.关键词
路基边坡/可靠指标/分项系数/负偏调控/残差趋低Key words
Subgrade slope/Reliability index/Partial factor/Negative deviation control/Residual minimization分类
交通工程引用本文复制引用
张文生,罗强,于基宁,蒋良潍,覃李兵..基于可靠指标负偏调控的路基边坡分项系数标定[J].中国铁道科学,2025,46(3):42-51,10.基金项目
国家自然科学基金资助项目(52078435) （52078435）
中铁第一勘察设计院集团有限公司技术开发项目(2021KY56YB-10-01) （2021KY56YB-10-01）
