论文部分内容阅读
为评估含水率变化对高速铁路无砟轨道基床表层级配碎石动力性能的影响,本文针对最优含水率和饱和含水率两种状态下级配碎石循环动力性能开展室内大型动三轴试验研究,分析级配碎石的临界动应力和累积变形特性。研究表明:累积变形与荷载作用次数、含水率关系密切,荷载作用次数超过10 000次后,含水率的影响逐渐显现,荷载作用次数达到20 000次时,饱和含水率的累积变形相对最优含水率增大70%;不同含水率级配碎石的衰减型和破坏型累积变形曲线可分别用Stewart模型和Monismith模型预测;级配碎石临界动应力随含水率增大而减小,随围压的增大线性增大,饱和含水状态对应的临界动应力较最优含水状态平均小13%。
In order to evaluate the influence of moisture content on the dynamic performance of surface graded macadam on the ballastless bed of high-speed railway, aiming at the dynamic performance of graded macadam under the conditions of optimal moisture content and saturated moisture content, Experimental study was conducted to analyze the critical dynamic stress and cumulative deformation of graded aggregate. The results show that the cumulative deformation is closely related to the number of loadings and the water content. After the number of loadings exceeds 10,000, the effect of water content gradually becomes apparent. When the number of loadings reaches 20,000, the cumulative deformation of saturated water content is relatively optimal The rate of increase of 70%; different moisture content of graded gravel attenuation and failure of the cumulative deformation curves can be predicted using the Stewart model and the Monismith model; graded gravel critical dynamic stress decreases with the increase of water content, with the surrounding The increase of pressure increases linearly, and the critical dynamic stress corresponding to saturated water content state is 13% smaller than that of the optimal water content condition.