基于响应面法的合肥滨湖新区湖相软土的固化配比试验研究

Experimental Study of the Optimizating Mixture Ratio of Lacustrine Soft Soil of the Hefei Binhu District by Response Surface Methodology

针对合肥滨湖新区地域性湖相软土的特点,采用MgO和石膏作为辅剂掺入GGBS(Ground Granulated Blastfurnace Slag,粒化高炉矿渣)固化合肥湖相软土,通过无侧限抗压强度试验研究固化土的强度变化规律。以GGBS、MgO和石膏的掺量作为变量因子,以固化土的7d和28d养护龄期的无侧限抗压强度作为响应值,基于旋转中心组合法确定3种固化成分的最佳配合比。研究表明:养护7d后,GGBS和MgO对固化土强度的线性作用显著,GGBS对其强度的曲面作用显著,GGBS与MgO及石膏与MgO的交互作用同时显著;养护28d后,GGBS和MgO对固化土强度的线性作用、曲面作用以及交互作用等均显著。最终得出:GGBS、MgO和石膏三掺量固化黏土最佳配比分别为12.00%、2.50%和5.98%,在最佳配合比下7d和28d的预测强度分别达到1206.99 k Pa,2040.38 k Pa。最后对实测值与预测值进行了对比分析。研究成果表明该法针对地域性合肥湖相软土固化配比研究具有一定的理论参考意义。

In view of the characteristics of soft soil in the area of Binhu New District of Hefei,using MgO and gypsum as auxiliary agent to mix GGBS(Ground Granulated Blastfurnace Slag)solidified Hefei Lake soft soil,the strength variation law of solidified soil is studied by unconfined compression strength test.The content of GGBS,MgO and gypsum was used as a variable factor,the unconfined compressive strength of7d and28d curing age of solidified soil was used as the response value,and the optimum mix ratio of3kinds of curing components has been determined based on rotation center combination method.The study shows that GGBS and MgO has a significant linear effect on the strength of solidified soil after curing7d,GGBS has a significant effect on the surface of its strength,the interaction of GGBS and MgO and gypsum with MgO was significant at the same time;and after curing28d,GGBS and MgO have a significant effect on the strength of solidified soil,such as the linear function,the surface interaction and the interaction.Finally it can be concluded that the optimal ratio of GGBS,MgO and gypsum in three dosage of solidified clay is12%,2.50%and5.98%,respect ively,and the predicted intensities of7d and1206.99kP a were28d and2040.38kP a,respectively.Finally,the measured values and predicted values are compared and analyzed.The research results show that this method has a certain theoretical reference value for the study of the proportion of the soft soil in Hefei lake.