振杆密实法加固粗粒混合土模型试验OA北大核心CSTPCD

Coarse-grained mixed soil is widely distributed across China's central and western regions.Its loose nature and unevenness present challenges when using these materials as foundations for structures.This study proposes using the vibration probe compaction method to enhance the bearing capacity of these foundations and eliminate unevenness.The primary research method involves conducting indoor model experiments,including vibratory compaction tests,lightweight dynamic probing tests,and density measurement tests.These experiments incorporate real-time monitoring of vibration and settlement indicators to assess the consolidation effects of the vibration probe compaction method on coarse-grained soil.Additionally,the study evaluates the impact of parameters such as the k-value(d90/diameter of the probe)and vibration frequency on the ef-fectiveness of the consolidation.The findings reveal that after vibratory treatment,the average number of lightweight dynamic probing blows in-creases to 13,an increase of 11 compared to before treatment.The average compaction degree at the bottom of the specimen reaches 81%,enhan-cing the bearing capacity by over 200 kPa.The treated soil becomes a low-compressibility foundation;when the k-value is 1/2.0,the reinforce-ment effect is superior to that when the k-value is 1/10.0,with the former exhibiting approximately 50 kPa higher bearing capacity and a 7%high-er settlement rate compared to the latter.When applying a 14 Hz vibration frequency to coarse-grained mixed soil,the ground vibration velocity reaches 36 mm/s.The HHT spectrogram showed a significant seismic response of around 14 Hz using the Hilbert-Huang Transform(HHT)on the collected vibration data.Employing a triangular arrangement for reinforcement points eliminates unevenness in the foundation soil.The uneven-ness coefficient(K)decreases from 26.4 before the experiment to 1.39 after.The vibration probe compaction method offers a novel technique for improving the foundations of coarse-grained mixed soil and provides essential parameters for on-site construction.