Vibration safety evaluation and vibration isolation control measures for buried oil pipelines under dynamic compaction: A case study

Abstract

As a common treatment method to improve the bearing capacity of soft soil sites, the strong impact vibration generated by dynamic compaction (DC) has adverse effects on the surrounding environment and adjacent structures. In this paper, a series of in-situ tests were conducted to evaluate the vibration safety of adjacent buried oil pipelines under DC shock. The vibration responses and attenuation rules of the site were analyzed. Meanwhile, a numerical method was employed to discuss and determine the minimum tamping distance and rational parameters for isolation trench. Furthermore, the vertical peak vibration velocity index was used to evaluate the vibration safety of the pipeline under DC load. The results show that the vibration response of the site is manifested as vertical vibration and horizontal vibration, while the vibration response of the buried pipeline is dominated by vertical vibration. The empty trench can block the propagation of vibration waves effectively, in which the depth and its distance to the ramming point are the main factors affecting the vibration isolation effect. The vibration isolation effect of the trench increases with the increase of trench depth and the decrease of the distance from the tamping point. The study proposed parameters for an empty trench with a depth of 5 m and a safety distance of 5 m from the compaction point for the final ground treatment scheme. Good results have been achieved in engineering practice. The analysis results provide new ideas and references for promoting the application of underground pipeline vibration protection technology in DC ground treatment.