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为了解决多年冻土区路基变形控制与稳定性问题,满足高海拔多年冻土区路基调控措施的选型需求,以青藏公路、国道214线共和至玉树公路、中科院北麓河高等级试验公路中已试验应用的一些典型路基调控措施为研究对象,采用实测数据分析、数值模拟等方法,将实体试验工程长时间序列监测数据反映的情形与数值模拟结果对照,并结合道路运营状态调查等技术手段对各类典型调控措施的长期作用效能进行验证,探讨其在高等级公路中的适应性。研究表明:隔热层工程措施、热棒工程措施、空心块护坡工程措施等基于温度调控的冻土路基变形调控措施,主要通过减少路基基底吸热、调控路基基底温度场的变化趋势与强度,实现对冻土路基变形进行调控,它们对路基自身结构安全与稳定性要求较高,长期作用效能没有达到设计预期,该类调控措施在路基变形调控应用中不宜单独使用,应注重与其他调控措施组合使用;块石路基、通风管路基、全断面通风路基等主要基于水、热同时调控的工程措施,它们通过减弱水的影响,对流换热增加基底冷储量,减少路基体水热影响作用明显,虽然也存在有些措施热效能不足、路基基底整体处于净吸热状态的问题,但其自身结构力学稳定性和水稳定性较好,综合使用效能经长期观察是积极的,路基变形能基本达到设计预期。
In order to solve the problem of deformation control and stability of subgrade in permafrost region and to meet the selection of subgrade control measures in permafrost region at high altitude, Qinghai-Tibet Highway, State Road 214 Republican to Yushu Highway, Chinese Academy of Sciences Beiluhe High Grade Experimental Highway Some typical subgrade control measures which have been tested are taken as the research object. The measured data and numerical simulation are used to compare the situation reflected by the long-time series of monitoring data of the physical experimental project with the numerical simulation results. Combined with the technical means such as road operation status investigation, To verify the long-term effectiveness of various typical control measures and to explore their adaptability in high-grade highways. The research shows that the control measures of permafrost embankment deformation, such as engineering measures of insulation layer, engineering measures of hot rod and hollow block slope protection engineering measures, mainly control the change tendency and intensity of the temperature field of subgrade by reducing the endotherm, So as to control the deformation of permafrost embankment. They have high requirements on the structural safety and stability of subgrade and the long-term effectiveness does not meet the design expectation. Such control measures should not be used alone in the application of roadbed deformation control, and should be emphasized in combination with other control measures Which are mainly based on the engineering measures of simultaneous regulation of water and heat, such as block stone embankment, ventilating pipe embankment and full-section ventilated embankment. By reducing the influence of water, they increase the base cold storage of convective heat transfer and reduce the influence of water and heat on the roadbed Although there are also some measures, such as insufficient thermal efficiency and subgrade endothermic net endothermic condition, the mechanical stability and water stability of the subgrade are good. The long-term comprehensive effectiveness can be observed by long-term observation and the subgrade deformation can be basically achieved Design expectations.