粉细砂地层条件下声频振动注浆的试验研究

Experimental Study on Audio Frequency Vibration Grouting in Fine Silty Sand Layer

摘要:

粉细砂地层加固处理工作一直是工程界研究的重点课题，采用传统注浆工法很难达到预期效果。针对此种情况，近年来提出振动注浆法，然而目前的振动注浆模拟试验与实际工况有较大出入，故创新设计了试验装置，可以满足自由调控振动频率，且振动效果与实际工况接近。通过室内静压注浆试验及声频振动注浆试验，对比注浆效果，得出以下结论：压力相同条件下，相比静压注浆，振动注浆可以有效增大注浆量且加固效果更优；振动频率的适当增加可以有效加快注浆速度，增大注浆量，这对于工期紧张的工程具有一定的实际意义，但频率过高并非完全有利于注浆效果，要根据实际工国家自然科学基金面上项目“声频振动钻进系统共振机理及能量传递规律研究”（编号：41672366）；北京市优秀人才项目“声频振动钻进工艺技术研究”（编号：2013D009015000002）况选择最优注浆频率；高频振动下，振动时间的延长对注浆效果的增益较小。

关键词:粉细砂土地层;静压注浆;声频振动注浆;模拟试验;浆液扩散机理

Abstract:

The reinforcement processing of fine silty sand layer has been the important subject in the engineering field, for it is hard to achieve the desired effect by the traditional grouting method. In view of this situation, the vibrating grouting method is put forward in recent years. However, there are many discrepancies between present vibration grouting simulation tests and the actual working conditions. A test device has been creatively designed, which can satisfy the regulation of freedom vibration frequency and vibration effects is closed to the actual conditions. Comparing the grouting effects of the indoor static pressure grouting test to the audio frequency vibration grouting test, the following conclusions are presented: under the same pressure, the vibration grouting can effectively increase the grouting quantity with better reinforcement effect compared with the static pressure grouting; the appropriate increase of vibration frequency can effectively accelerate the speed of grouting and increase the grouting quantity which has certain practical significance for the project with time limit. However too high frequency is not totally beneficial to the grouting effect, it is crucial to select the optimum grouting frequency according to the actual condition. Under high frequency vibration, the extension of time has less influence to the grouting effect.

Key words:fine silty sand layer; static pressure grouting; audio frequency vibration grouting; simulation test; grouting diffusion mechanism