将洪水量作为随机变量,以Rosenbleuth法为可靠度分析方法,评价路基抗冲刷可靠度。为解决定量计算不宜考虑洪水冲刷作用的问题,提出了模糊可靠度方法,将洪水量、路基所处位置、路基边坡防护措施和养护维修情况作为影响路基抗冲刷稳定性的因素,定性评价洪水冲刷作用下路基的可靠度,进一步研究了洪水量变异性对路基抗冲刷可靠度的影响,结果表明:随着洪水量变异系数的增大,路基抗冲刷的平均稳定安全系数稍有增大。在较小变异系数下,可靠指标变化明显;随着变异系数的增加,可靠指标变化逐渐减小。将提出的方法应用到天山公路中,该研究可以为沿河路基设计和水毁可靠度评价提供科学依据。
Taking flood volume as the random variable, the subgrade reliability along river is analyzed by using Rosenbleuth method to evaluate the subgrade reliability in erosion of flood. Because the erosion effect of flood is not easy to be considered in quantitative calculation, so Fuzzy reliability method is used to evaluate the subgrade reliability. Flood volume, position of subgrade, protection measure of subgrade slope and maintenance are regarded as the influencing factors of subgrade stability in erosion effect to quantitatively evaluate the subgrad flood volume on the e reliability in erosion of flood. Furthermore, the influence of the variation coefficient of subgrade reliability is studied. The result shows that (1) the average safety factor of subgrade increases a little with the increase of the variation coefficient of flood volume, the reliability index changes obviously when the variation coefficient of flood volume is smaller; (2) the reliability index decreases gradually with the increase of variation coefficient of flood volume. The method is applied to Tianshan highway to analyze its reliability, and results are reasonable. This research provides an important basis for the reliability evaluation and design of subgrade along river.