【作者】 滕文彦；

【导师】 乔春生；

【作者基本信息】 北京交通大学 ， 岩土工程， 2011， 博士

【摘要】 高速公路路基将长期承受行车荷载及其它自然因素的影响,土体强度特性的逐渐退化将引起路基破坏、路面不平顺甚至开裂,影响其路用性能。本文结合河北省沧黄高速公路工程实际,采取理论分析与实验研究相结合的研究思路对滨海水网区路基填料的静、动强度特性及长期稳定性进行了全面系统的研究。主要研究成果如下：(1)提出了适合于滨海水网区路基填料的土水特征曲线,揭示了水分迁移对路基强度的影响规律。(2)试验研究了基于雨水入渗、蒸发、地下水毛细作用以及水分迁移引起的干湿循环条件下路基填料性能衰减规律,揭示了循环次数对路基土强度及变形特性影响规律(3)基于大量的静、动三轴试验,研究了路基填土及其石灰改良土的强度、变形规律,提出了含水量变化路基工程特性的影响及性能衰减规律。(4)分析了交通荷载在路基结构中的竖向分布规律,建立了交通荷载下路基动力三维有限元计算模型,分析了交通循环荷载对滨海水网区路基工作性状的影响,揭示了交通循环荷载作用下路基含水量变化对其沉降的影响规律,提出了相应的技术对策,解决了滨海水网区路基长期稳定性问题。更多还原

【Abstract】 The highway subgrade bear long-term traffic loads and influence from other natural factors. Under the circumstances, soil strength characteristics degenerate gradually, and eventually they will lead to damage of subgrade, unevenness and even crack of pavement. All of these will affect the performance of the highway. Based on the Cang-Huang highway engineering, in coastal water net area, in hebei province, the dynamic, static strength properties and long-term stability of subgrade filling were researched in these dissertation, with the ideas of theoretical analysis and experimental research. The main research results are as follows:(1) The water-soil characteristic curve in coastal water net area of soil subgrade filling was put forward, and the influence law of roadbed strength from moisture transfer was revealed.(2) The performance decay laws of subgrade filling were studied based on the rain infiltration and evaporation, groundwater capillary function and dry-wet cycling condition. The influence law of the subgrade soil strength and deformation characteristics were revealed with the cycle times.(3) The strength and deformation of subgrade filling and lime improved soil were studied based on a lot of static and dynamic triaxial test. The subgrade engineering characteristics and performance decay laws were put forward with the water content.(4) The vertical distribution of the traffic load in embankment structure were analyzed. The engineering characterics of subgrade in coastal water net area were analyzed under traffic load, according to the 3D finite element calculation model of dynamic traffic cyclic loading. The subgrade settlement coming from the moisture content changes under traffic cyclic loads was revealed. The corresponding technical countermeasures was put forward and the long-term stability of subgrade was solved.更多还原