Using aluminum–organic matter flocs to mitigate water–soil gushing disasters in underground structures
摘要
In water-rich sand strata, underground structures face leakage risks, and previous disaster-mitigation strategies had limitations. This paper presented a method of using aluminum–organic matter (Al-OM) flocs as a grouting material to mitigate water–soil gushing disasters in underground structures. Through 1D column experiments, it is found that the Al-OM flocs feature outstanding injectability under low injection pressure. After grouting, the hydraulic conductivity of the sand decreases by 27 times, and the Al-OM flocs showed sufficient resistance against seepage flow. Disaster mitigation tests, with a model box divided into two sand tanks, were conducted. Four groups of tests were carried out to evaluate the performance of the Al-OM flocs. The results show that the grouting barrier formed by the Al-OM flocs can enhance the drawdown by a factor of 2.5 and improve the dewatering efficiency by 3.5 times. It can effectively inhibit soil erosion, with the eroded area being smaller compared to the case without grouting. The combined use of the Al-OM flocs grouting barrier and dewatering could further enhance dewatering efficiency and significantly reduce soil erosion. Notably, the Al-OM flocs grouting barrier show remarkable effectiveness in retarding the water level recovery after dewatering. This provides more time for emergency rescue operations.