Analysis And Assessment On Environmental Vibration Due To Dynamic Compaction

Dynamic compaction method was widely-used in the foundation consolidation around the world because of its simple constructing procedure and low cost. Simultaneously, the surface vibration caused by dynamic compaction has different degrees impacts on the adjacent buildings, even on human health and the use of exact instruments which resulted in the dispution and delay of works.As the energy due to dynamic compaction spread in soil as the form of wave, both the radial acceleration (speed) and the vertical acceleration (speed) decay with the distance increase because of the material and geometry damping .when the wave reached a certain place, the strength of the wave is very small and almost have no impact on surrounding buildings, that is the safe distance.As so far, the studies of dynamic compaction was focused on the attenuation of the vibration and the safe distance to order the construction plan and adopt the reasonable isolation measures.The roadbed has to be disposed by dynamic compaction for the complicated condition of geology. The impact on constructions and environment due to the dynamic compaction should be taken into account. Based on the 207 group-dynamic vibration acceleration collected in-situ of the highway roadbed construction,the peak acceleration, peak velocity, vibration frequency were analyzed in details. The attenuation rule of the dynamic compaction was developed. A six-storey and a three-storey housing models were founded to progress the histories analysis, assessment on vibration was made according to vibration response datas.Be lack of uniform appraisal standard, the environmental vibration owing to the dynamic compaction was evaluated referring to the main criteria of domestic and foreign standards.The safe distance was proposed according to "China Earthquake Intensity Table". The conclusions of environmental vibration assessment were incompatible according to different criterias for different vibration parameters were considered. Some meaningful advises to modify the existing appraisal standards on the environmental vibration were appointed, as well.