静动力排水固结法处理淤泥软基振动试验研究

对于高含水率、大孔隙比的深厚淤泥地基，在静动力排水固结法处理中，采用组合式高效夯击减震锤（SAAT）等4种不同形状尺寸的典型夯锤，以975～1 125 kN•m单击夯击能夯击，进行场地振动加速度及夯沉量原位对比测试，获得SAAT夯锤与地基土首次接触、回弹和二次作用历时分别为15，80，35 ms，各锤作用下竖向与水平向加速度分别在10 m与5 m距离内急剧降低，得到满足规范（烈度Ⅶ度）安全要求时SAAT及各夯锤夯击综合安全距离为20～30 m，其中SAAT所需安全距离最小。结果表明，采用SAAT可明显提高夯击效率，并可有效地减小对周边环境的振动影响。此外，对该条件下夯击冲击波的传播及衰减规律进行了总结与分析。

In-situ tests and analyses on vibration influences during mud ground improvement with static-dynamic drainage consolidation

Under the condition of tamping energy 975－1 125 kN•m per blow with four kinds of typic tampers including the shock absorbed and assembled tamper (SAAT) designed by the first author, the tests of vibration acceleration and comparative tamping settlement are carried out in-situ during the improvement of mud ground with high water content and great void ratio by using the static-dynamic drainage consolidation (SDDC); SAAT first contact with ground, rebound, and impact secondary action lasted for 15ms, 80 ms and 35 ms respectively; vertical and horizontal acceleration under the four temper action descend sharp within 10 m and 5m respectively; the synthesized safety distances satisfying the requirement of relevant code (under seismic intensity grade Ⅶ）are obtained as 20－30 m under the condition, and the safety distance for SAAT is least; the result shows that the SAAT enhances the effect of MSDDC in evidence and diminishes vibration influence on surrounding environment obviously. Besides, transmissions of vibration acceleration produced by impacting are analyzed.