基于模量法评价碎石土路基压实效果的试验研究

Evaluation of compaction effect of gravel soil subgrade by modulus method

针对碎石土路基的工程特点,通过模拟实际工况,采用承载板试验和便携式落锤弯沉仪检测不同含石量及加筋情况下碎石土路基的反应模量、动回弹模量。基于试验结果,分析了不同含石量和加筋情况对碎石土路基反应模量、动回弹模量的影响。研究结果表明,在同一压实度下,碎石土路基反应模量和动回弹模量随含石量的增加而增加,且压实度越高,增大含石量对提高碎石土路基反应模量、动回弹模量作用越显著;在相同压实度下,碎石土路基反应模量和动回弹模量随加筋层数的增加而增加,且在较低压实度下,加筋对提高碎石土路基反应模量、动回弹模量作用更显著。基于填土体(包括加筋土体)压实度与模量之间的内在联系,提出了反应模量、动回弹模量与压实度之间的函数关系。结合公路路基设计规范,建立了碎石土路基反应模量和动回弹模量的评定标准。本文研究成果对工程实践中碎石土路基压实效果评价具有指导意义和借鉴价值。

According to engineering characteristics of gravel soil subgrade,and through simulating the actual working conditions,this paper has applied the bearing plate test and the portable falling weight deflectometer to detect the reaction modulus and dynamic resilience modulus of gravel subgrade under different gravel content and reinforcement conditions.Based on the test results,the effects of different gravel content and reinforcement conditions on the reaction modulus and dynamic resilience modulus of gravel subgrade are analyzed.The results showed that under the same compaction degree,the reaction modulus and dynamic resilience modulus of gravel subgrade increase with the increase of gravel content,and the higher the compaction degree,the more significant increasing effect of the gravel content on the improvement of the reaction modulus and dynamic resilience modulus.The reaction modulus and dynamic resilience modulus increase with the increase of the number of reinforced layers,especially when the compaction degree is low.Based on the intrinsic connection between the compaction degree and the modulus of the filled soil(including the reinforced soil),the functional relations between the reaction modulus,the dynamic resilience modulus and the compaction degree are proposed.Referring to the design specification of highway subgrade,this paper proposes the evaluation criteria of reaction modulus and dynamic resilience modulus of different parts of gravel soil subgrade.The research results have practical significance for testing and evaluating the compaction effects of gravel soil subgrade in engineering practice.