砂柱微生物注浆的水力渗透性质试验研究

为了有效实现防渗堵漏,对砂柱微生物注浆的水力渗透性质进行试验研究。砂柱微生物注浆采用巴氏芽孢杆菌菌种,向试验装置中注入胶结液与菌液,静置完成微生物注浆。对实际工程问题物理模型进行简化处理,构造满足工程特性的数学模型,对模型赋予参数、初始条件及边界条件,为砂柱微生物注浆水利渗透性质试验提供依据。构造均质高孔隙率砂岩非稳定达西渗流数学模型,计算可体现砂柱微生物注浆水力渗透性质的孔隙率与渗透率。将已有实验结果和数值模拟结果进行比较,对数值模型合理性进行验证。通过观察孔隙率与渗透率对砂柱微生物注浆的水利渗透性质进行试验分析。结果发现,砂柱微生物注浆可降低砂柱孔隙率与渗透率,提高砂土水力渗透性质。

Experimental study on hydraulic permeability of sand column microbial grouting

In order to effectively prevent seepage and plugging, the hydraulic permeability of sand column microbial grouting is studied. Bacillus pasteurius strains were used in sand column microbial grouting, cementing fluid and bacterial liquid were injected into the test device, and microbial grouting was completed by static placement. The physical model of practical engineering problems is simplified to construct a mathematical model which satisfies the engineering characteristics. The parameters, initial conditions and boundary conditions are given to the model. The unsteady Darcy seepage mathematical model of structural homogeneous sandstone with high porosity can be used to calculate the porosity and permeability which can reflect the hydraulic permeability of microbial grouting in sand column. The rationality of the numerical model is verified by comparing the existing experimental results with the numerical simulation results. The permeability of water in sand column microorganism grouting is analyzed by observing porosity and permeability. The results show that microbial grouting can reduce the porosity and permeability of sand column and improve the hydraulic permeability of sand.