为研究地震荷载作用诱发的场地土震陷问题,以辽西地区风积土为研究对象,进行了50年超越概率2%和10%的人工地震荷载及等幅正弦荷载作用下风积土的震陷试验,建立了风积土震陷系数经验公式;依据分层总和法预测了人工地震荷载作用下风积土场地震陷量,并对其震陷性进行了评价。研究结果表明,震陷系数随动应力幅值、试件含水量和孔隙比的增加而增大,其中动应力幅值对震陷系数的贡献最大,其次为含水量和孔隙比。震陷评价结果表明,若计算深度为20m,场地可判别为中等震陷区;若计算深度为15m,场地属轻微破坏区。以上研究成果为辽西地区风积土地基的抗震防震设计提供了参考依据,具有一定的的工程应用价值。
Abstract: In order to research the seismic settlement of ground soil induced by seismic loads, the seismic settlement tests of aeolian soil in west of Liaoning Province were conducted under the artificial seismic loads with the probabilities of exceedance of 2% and 10% in the future 50 years and constant amplitude sinusoidal loads. The empirical formula of aeolian soil' s seismic subsidence coefficient was established based on 3 different dynamic constant amplitudes tests data. Aeolian soil field' s subsidence values under the above two seismic loads were predicted according to layerwise summation method and its seismic subsidence was assessed. Research results show that, the seismic subsidence coefficient increases with increase of the dynamic stress amplitude and speciment' s water content and void ratio. The order of the seismic subsidence ratios'impact factors is dynamic stress amplitude, water content and void ratio. The seismic settlement evaluation results show that, if the calculation depth is 20m, the aeolian soil field can be discriminated aeolian soil field can be discriminated as the seismic design of aeolian soil region in as intermediate settlement region; if slight west settlement region. The research the calculation depth is 15m, the results will provide a reference to of Liaoning Province and has a certain engineering practical values