季节冻土区长期交通荷载下公路路基永久变形特性

发布时间：2018-03-12 17:02

本文选题：公路路基　切入点：永久变形　出处：《哈尔滨工业大学学报》2017年03期 　论文类型：期刊论文

【摘要】：为研究季冻区公路路基在长期交通荷载作用下永久变形的累积规律,首先基于室内试验获取的路基融土永久应变经验公式,提出季节冻土区路基永久变形计算步骤;并通过建立的基层-路基-地基有限元模型,研究汽车轴型、后轴轴重、行车速度和路基融化厚度对正常期和春融期路基应力比和永久变形的影响.计算结果表明:正常期路基的应力比随着埋深的增加逐渐减小,融化路基应力比较正常期大,冻结路基内较正常期小;六轴汽车产生的永久变形大于其他4种轴型汽车;路基内的应力比和永久变形随后轴轴重和路基冻融影响厚度的增加而显著增大;行车速度越低,路基内应力比和永久变形越大.据此提出了季节冻土区长期公路交通荷载作用下路基永久变形预测公式.
[Abstract]:In order to study the accumulative law of permanent deformation of highway roadbed in seasonal frozen region under long-term traffic load, based on the empirical formula of permanent strain of subgrade thawing soil obtained by indoor test, the calculation steps of permanent deformation of roadbed in seasonal frozen region are put forward. Through the finite element model of base-roadbed and foundation, the axle type and rear axle load of automobile are studied. The effect of driving speed and thawing thickness on the stress ratio and permanent deformation of subgrade in normal period and spring period. The calculation results show that the stress ratio of subgrade decreases gradually with the increase of buried depth, and the stress of melting subgrade is larger than that of normal period. The permanent deformation of six-axle vehicle is larger than that of the other four axle type vehicles; the stress ratio and permanent deformation in the roadbed increase significantly with the increase of axle load and roadbed freeze-thaw effect thickness; the lower the driving speed, the lower the driving speed. The greater the stress ratio and permanent deformation of subgrade, the prediction formula of permanent deformation of roadbed under the action of long-term highway traffic load in seasonal frozen soil region is put forward.
【作者单位】：哈尔滨工业大学交通科学与工程学院;哈尔滨工业大学土木工程学院;
【基金】：国家重点基础研究发展计划(2012CB026104) 国家自然科学基金(51408163,51578200) 黑龙江省自然科学基金重点项目(ZD201218) 中国博士后科学基金(2012M520751)
【分类号】：U416.1

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