摘要
利用FLAC 3D数值计算软件,建立了强夯振动的有限差分模型,分析了路侧地基强夯振动在公路路基、路面中的传播规律。以关键测点的振动加速度与锤底土动压力值作为分析指标,分析了夯锤落距(锤重)、夯锤直径对路基、地基的振动和地基加固效果的影响规律。通过公路拓宽室内模型试验,验证了数值分析的可靠性。结果表明,在1 500 k N·m夯击能下,采用6 m的夯锤落距(对应夯锤锤重为25 t)、1.5 m或2.0 m夯锤直径可以获得理想地基加固效果,且对周边环境振动影响最小;路基坡脚处强夯振动加速度较平面地形衰减更为显著;路面结构中振动加速度总体呈现快速衰减趋势,内侧加速度最大值为3.9 m/s2,路面基层、底基层内的强夯振动加速度基本一致,均小于面层的振动加速度。
By using FLAC 3D numerical calculation software,a dynamic compaction vibration finite difference model was built to analyze the dynamic compaction vibration propagation law of the roadside foundation in the subgrade and pavement structure. At the same time,the vibration acceleration of the key points and the rammer subsoil dynamic pressure value were made as double assessment indicators. The dynamic compaction vibration response of the subgrade and comprehensive evaluation of the foundation reinforcement effect with different parameters were obtained. Through the indoor model test,the reliability of the numerical analysis was verified. The tamping energy of 1 500 k N·m,drop height of 6 m（ corresponding rammer weight of 25 t） and rammer diameter of 1. 5 m or 2 m are used in the test. The result showed that a good foundation reinforcement effect can be reached as well as the minimal vibration effects on the surrounding environment. Compared with flat terrain,the dynamic compaction vibration acceleration attenuation at embankment toe is more significant. For all,the pavement structure vibration accelerations tended to be a rapid decay. The medial maximum acceleration reached to 3. 9 m / s2. The compaction vibration＇s acceleration of road base and sub-base does not significantly change,which both are less than the surface layer.
出处
《科学技术与工程》
北大核心
2015年第8期208-213,共6页
Science Technology and Engineering
关键词
路基加宽
地基
强夯振动
路基路面
传播规律
subgrade widen foundation dynamic compaction subgrade structure propagation law
