激振作用下坠落式危岩振动特性试验研究

发布时间：2018-09-08 21:33

【摘要】：根据坠落式危岩与基岩的接触模式,设计4个主结构面贯通率分别为25%,40%,55%和70%的坠落式危岩试验模型,采用不同大小及不同方向的激振力对基岩进行激振,研究激振作用下不同贯通率坠落式危岩振动特性。研究表明:同一激振方式下,主结构面的贯通率越大,危岩与基岩的接触稳固性越差,危岩与基岩的振动差异越大,危岩的振动响应更明显且振动的衰减越慢;随着贯通率的增大,危岩的卓越频率和阻尼比减小,危岩与基岩的RMS加速度振幅比增大;当主结构面贯通率从25%增大到70%时,危岩的卓越频率从375Hz减小到89Hz,减小了76.3%,危岩与基岩的RMS加速度振幅比从2.0增大到6.9,增大了2.45倍,阻尼比从0.081减小到0.049,减小了39.5%,贯通率对危岩的卓越频率和危岩与基岩的RMS加速度振幅比影响较大,对阻尼比的影响次之;在本试验激振力范围内,不同激振方式下,同一贯通率危岩的卓越频率、阻尼比以及危岩与基岩的RMS加速度振幅比的变化较小。
[Abstract]:According to the contact mode between falling dangerous rock and bedrock, four test models of falling dangerous rock with penetration rate of 25% and 70% are designed, and the exciting force of different magnitude and direction is used to excite the bedrock. The vibration characteristics of perilous rock with different penetration rates are studied. The results show that under the same excitation mode, the greater the penetration rate of the main structural plane, the worse the contact stability between the perilous rock and the bedrock, the greater the difference of the vibration between the perilous rock and the bedrock, and the more obvious the vibration response of the perilous rock is and the slower the vibration attenuation is. With the increase of penetration rate, the excellent frequency and damping ratio of perilous rock decrease, and the RMS acceleration amplitude ratio of perilous rock to bedrock increases, and when the penetration rate of main structural plane increases from 25% to 70%, The excellent frequency of perilous rock decreases from 375Hz to 89Hz, and the ratio of RMS acceleration amplitude of perilous rock to bedrock increases from 2.0 to 6.9, which increases by 2.45 times. The damping ratio is reduced from 0.081 to 0.049, which decreases 39.5%. The penetration ratio has a great influence on the excellent frequency of dangerous rock and the ratio of RMS acceleration amplitude of dangerous rock to bedrock, followed by damping ratio. The excellent frequency, damping ratio and RMS acceleration amplitude ratio of the perilous rock with the same penetration rate have little change.
【作者单位】：中国铁道科学研究院;中国铁道科学研究院高速铁路轨道技术国家重点实验室;中国铁道科学研究院铁道建筑研究所;贵州大学资源与环境工程学院;
【基金】：中国铁路总公司科技研究开发计划项目(2014Z003-A,2014Z003-B,2014Z003-D);中国铁路总公司铁道科学技术研究发展中心项目(J2014G006) 中国铁道科学研究院行业服务技术创新项目(2013Y024)
【分类号】：TU45

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