改扩建路基结合部典型病害的地震波传播特征分析OA

Accurate identification of defects at the junction of reconstructed and expanded subgrades is crucial for ensuring road operational safety.Two-dimensional numerical models incorporating typical defects,such as cavities,fractures,and incompactness,are established based on the seismic wave method to analyze the influence of these defects at different locations and of various types on seismic wave propagation characteristics.Multiple geophones are deployed on the model surface to collect data for time-domain,frequency-domain,and time-frequency analysis.The results indicate that defects at different locations and of various types significantly affect seismic wave propaga-tion.Among these,shallow defects,as well as elongated voids,circular voids,and fractured defects,induce the most intense wavefield disturbances,exhibiting higher identifiability.Conversely,deep defects,rectangular voids,and incompact defects with limited dimensions show less distinct disturbance characteristics,making them more challenging to identify.The multi-dimensional feature extraction method effectively reveals the time-frequency evo-lution law of defect interference.