竖向振动加速度三维特征图在地基注浆加固质量检验中的应用
Application of Three-Dimensional Characteristic Diagram of Vertical Vibration Acceleration in Quality Inspection of Foundation Grouting Reinforcement

动力设备基础注浆加固效果的质量检验通常采用标准贯入、静力触探等原位测试方法，但是生产繁忙、空间狭小的厂房无法满足原位测试条件。由此，本文提出了一种地基注浆加固质量检验的振动加速度三维特征图法：在加固范围内合理选取测点，采集各测点的三维加速度时程记录；分析反映能量特性(均方值、方差、均方根值)、冲击特性(峰值因数、脉冲因数、裕度因数)、分布特性(峭度、偏度指标、偏态因数)的时域指标，在三维坐标系中绘出各指标的特征点，加固前、后所有测点的特征点形成振动加速度三维特征图，由此可以直观、全面、准确地评价地基加固效果。通过研究一大型精密设备地基注浆加固工程验证了该方法的有效性：加固后各测点反映能量、冲击、分布特性的时域指标均有不同程度的降低，表明注浆加固效果良好。
The quality inspection of grouting reinforcement effect of power equipment foundation usually adopts in-situ test methods such as standard penetration and static cone penetration. However, the factory with busy production and narrow space cannot meet the in-situ test conditions. Therefore, in this paper, a three-dimensional characteristic diagram method of vibration acceleration for quality inspection of foundation grouting reinforcement is proposed: The testing points are reasonably selected in the reinforcement range, and the three-dimensional acceleration time-history records of each testing point are collected. The time domain indexes reflecting energy characteristics (mean square value, variance, root mean square value), impact characteristics (crest factor, pulse factor, margin factor), and distribution characteristics (kurtosis, skewness index, skewness factor) are analyzed. The characteristic points of each index are drawn in the three-dimensional coordinate system. The characteristic points of all testing points before and after reinforcement form a three- dimensional characteristic diagram of vibration acceleration. Therefore, the effect of foundation reinforcement can be evaluated intuitively, comprehensively, and accurately. The effectiveness of the method is verified by studying a foundation grouting reinforcement project of large precision equipment: After reinforcement, the time domain indexes reflecting the energy, impact, and distribution characteristics of each testing point after reinforcement are reduced to varying degrees, indicating that the grouting reinforcement is effective.