基于正交试验的水泥浆液降失水研究

Research on Water Loss Reduction of Cement Slurry Based on Orthogonal Test

水泥土搅拌桩技术多用于软土的防渗加固处理,在砂卵石地层应用时经常会出现卡钻、搅拌困难等情况,施工效率较低,其中一个主要原因是砂卵石地层渗透系数大,水泥浆液抗失水性能差,会在孔壁形成较厚的泥皮,增大搅拌阻力。本次研究中,采用正交试验的方法,探究了水灰比、外加剂添加量等因素对水泥浆液失水量及滤饼厚度的影响,通过直观分析的方法,得出PVA掺量对水泥浆液的失水量和滤饼厚度影响最大,并得出最优配合比例。对实验结果进一步采用方差分析,发现PVA掺量对于失水量有显著影响,对于滤饼厚度有较轻影响。

Cement soil mixing pile technology is mostly used for anti-seepage and reinforcement treatment of soft soil.When it is applied in sandy pebble stratum,there are often problems such as stuck drilling and difficult mixing,and the construction efficiency is low.One of the main reasons is that the permeability coefficient of sandy pebble stratum is large,and the water loss resistance of cement slurry is poor,which will form thick mud skin on the hole wall and increase the mixing resistance.In this study,the orthogonal test method is used to explore the influence of water cement ratio,additive addition and other factors on the water loss of cement slurry and the thickness of filter cake.Through the intuitive analysis method,it is concluded that the content of PVA has the greatest influence on the water loss of cement slurry and the thickness of filter cake,and the optimal mix proportion is obtained.Further using the method of analysis of variance,it is found that the content of PVA has a significant effect on the water loss and a slight effect on the thickness of filter cake.