基于冲击映像法盾构同步注浆效果检测与评价

Detection and Evaluation of Shield Synchronous Grouting Effect Based on Impact Image Method

针对富水渗透性地层盾构施工同步注浆充填特性,将冲击映像法应用于盾构隧道壁后充填状态的探测。通过冲击弹性波的反射及其区域响应特征的波形分析,基于快速傅里叶变换获取测点冲击响应强度,并通过三维成像建立盾构隧道壁后注浆充填程度空间分布云图。在此基础上,建立检测工程数据样本空间内波形分布及冲击响应强度概率密度函数、风险演化函数,分别定量评价各测区及测线的充填状态及风险;通过检测区域内概率密度函数在对应风险区域的积分,建立盾构隧道同步注浆壁后充填状态综合评价体系。最后,通过工程案例验证了该方法的适用性。

Aiming at the characteristics of synchronous grouting and filling in water-rich and permeable stratum, the impact imaging method is applied to detect the filling state behind the shield tunnel wall. By the analysis of the reflection of shock elastic wave and its regional response characteristics, the impact response intensity of measuring points is obtained based on fast Fourier transform, and the spatial distribution cloud chart of grouting filling degree behind the shield tunnel wall is established by three-dimensional imaging. On this basis, the probability density function and risk evolution function of waveform distribution and impact response strength in the sample space of detection engineering data are established to quantitatively evaluate the filling state and risk of each survey area and line respectively;and a comprehensive evaluation system for the filling state behind the synchronous grouting wall of shield tunnel is established by integrating the probability density function in the corresponding risk area. The applicability of this method is verified by the engineering case.