The increased popularity of using a deep cement mixing (DCM) column as a ground improvement element in soft ground has brought about the need to identify how the targeted strength and stiffness values defined in guidelines can be achieved considering the water content and the incorporated cementitious materials. This paper addresses this important aspect by studying the strength and stiffness variations of DCM materials treated with various amounts of cement (5, 10, 15 and 20% by dry weight of soil) and Class F fly ash (10, 20 and 30% by weight of cement) as binders within the range of high total-water content variation of clayey, silty sand (40, 60, 80, 100 and 120% by dry weight of soil). The results were obtained after 28- and 90-day curing periods using unconfined compression strength (UCS) tests. The selected samples were also tested using unconsolidated and undrained and isotropically consolidated and undrained triaxial tests at the end of the curing periods. The parametric study extended further to specify the optimum strength and stiffness values among the considered factors. The current goal attainment optimisation method is utilised and evaluated further to enable the multi-objective desirability content and a high degree of regression to be included in the optimisation process. The paper draws specific conclusions, such as that the optimum moduli varies approximately in the ranges of 425–435 MPa and 846–863 MPa for the targeted UCS values of 1 MPa and 2.1 MPa.

在水泥地面上使用深层水泥搅拌（DCM）柱作为地面改良元素的日益普及，导致需要确定考虑水分含量和掺入的水泥材料如何实现准则中定义的目标强度和刚度值。本文通过研究用各种水泥（分别占土壤干重的5％，10％，15％和20％）和F级粉煤灰（按重量计10％，20％和30％）处理的DCM材料的强度和刚度变化来解决这一重要方面。在高黏度的粘土，粉质砂（占土壤干重的40％，60％，80％，100％和120％）的范围内，作为粘合剂使用。固化28天和90天后，使用无限制抗压强度（UCS）测试获得了结果。在固化期结束时，还使用未固结，不排水，各向同性固结和不排水的三轴测试对所选样品进行了测试。参数研究进一步扩展，以指定考虑因素中的最佳强度和刚度值。利用当前目标实现优化方法并对其进行进一步评估，以使多目标可取性内容和高度回归被包含在优化过程中。本文得出具体结论，例如，对于1 MPa和2.1 MPa的目标UCS值，最佳模量大约在425-435 MPa和846-863 MPa范围内变化。参数研究进一步扩展，以指定考虑因素中的最佳强度和刚度值。利用当前目标实现优化方法并对其进行进一步评估，以使多目标可取性内容和高度回归被包含在优化过程中。本文得出具体结论，例如，对于1 MPa和2.1 MPa的目标UCS值，最佳模量大约在425-435 MPa和846-863 MPa范围内变化。参数研究进一步扩展，以指定考虑因素中的最佳强度和刚度值。利用当前目标实现优化方法并对其进行进一步评估，以使多目标可取性内容和高度回归被包含在优化过程中。本文得出具体结论，例如，对于1 MPa和2.1 MPa的目标UCS值，最佳模量大约在425-435 MPa和846-863 MPa范围内变化。