沥青路面高密实度摊铺工艺参数研究

Process parameters of the high-compactness paving of an asphalt pavement

为了提高沥青路面的摊铺密实度,获得高密实摊铺效果,提出了一种考虑材料特性与摊铺压实力的熨平板-沥青混合料相互作用振动系统动力学模型。通过分析得出了熨平板的振动参数对沥青路面摊铺密实度的影响规律,得到了沥青路面高密实度摊铺的工艺参数范围。基于机械共振理论建立了熨平板压实机构非线性动力学模型,采用等效刚度和等效阻尼表示沥青混合料在摊铺压实过程中获得的压实力,用振幅放大因子β表示振幅的量级,得出了摊铺密实度趋势-振动频率的理论模型。通过分析模型,得到了振动参数和材料特性对摊铺密实度的影响规律,确定了材料高密实度摊铺的参数范围。通过现场试验,验证了工艺参数的高效压实区。研究结果表明:沥青路面高密实度摊铺对应的频率比λ范围是0.90~1.41;连续级配沥青混合料AC-20摊铺频率的高效压实区为33~49 Hz;仿真结果与试验结果的变化规律基本一致,模型具有有效性。该研究结果有利于提高沥青路面的摊铺密实度、提升路面质量、节约施工成本,为沥青路面的高效压实提供依据。

In order to improve the paving compactness of an asphalt pavement and the efficiency of paver construction,a dynamic model for the vibration system of screed asphalt mixture interaction,considering the material properties and paving compaction effort,was presented.The influence of vibration parameters of the screed on the asphalt pavement compactness was analyzed,and the technological parameter ranges of the high compactness paving of the asphalt pavement were obtained.Based on the mechanical resonance theory,a nonlinear dynamic model of the compacting mechanism of screed was established.The equivalent stiffness and damping were used to represent the compacting force of asphalt mixture in the process of paving compaction,the amplitude amplification factorβwas used to express the magnitude of the vibration,and the theoretical model for the paving compactness trend and vibration frequency was presented.By the model analysis,the effects of vibration parameters and material properties on the paving compactness was investigated,the parameter range of the high-compactness paving was determined.The high efficiency compaction zone for the technological parameter was verified by field tests.The results indicate that the frequency ratio range corresponding to the high density paving of the asphalt pavement isλ=0.9-1.41;the high efficiency compaction paving frequency band for the continuous gradation asphalt mixture AC-20 is 33-49 Hz;the variation rule of the simulation results is basically consistent with the test results,which verifies the validity of the model.The research results are helpful to improve the compactness of the asphalt pavement,improve pavement quality,save construction cost,and provide a basis for the effective compaction of asphalt pavements.