dc.contributor.author	Raftari, Mehdi
dc.date.accessioned	2024-12-02T03:45:44Z
dc.date.available	2024-12-02T03:45:44Z
dc.date.issued	2015
dc.description	Thesis (Ph.D (Civil Engineering))
dc.description.abstract	Deep Soil Mixing (DSM) method is a soil stabilization approach by mixing the insitu soil with stabilizing agents commonly known as soil-cement columns. The DSM technique increases the strength of the soil, and improves bearing resistance and settlement performance. The necessity to use this method has increased because of its economical and environmental friendly abilities. Most of research conducted to study the settlement behavior of soft soil treated with DSM method based on an incremental loading system by stress controlling devices. These loading conditions have some disadvantages such as long duration of tests where the strength of the stabilized soil changes with time. Due to these disadvantages, a Medium Rapid Consolidation Equipment (MRCE) was designed to quantify the impact of improvement area ratio and column dimension on the settlement of stabilized soil by DSM method. Thus, 20 physical modeling tests were prepared using consolidation technique on brown Kaolin clay. Considering the control of strain, the MRCE determines the settlement behavior of a group of soil-cement columns under different improvement area ratios (a) of 15%, 20%, and 30% and column improvement length / depth ratios (ß) of 25%, 50% and 75% in the different cement contents of 10%, 15% and 20%. The designed cement column installed in the soft kaolin clay ground were evaluated based on compression strength, settlement and hydraulic conductively. These specimens were examined on several mixtures consisting of kaolin clay in various dosages of Ordinary Portland Cement (OPC). The principal parameters including void ratio, cement - water content and curing time have been realized adequate to define the strength and compressibility of soil-cement columns. The procedure of physical modeling requires a suitable constant rate of strain to perform the consolidation tests. The constant strain rate of 0.020 mm/min was found to be compatible with the conventional consolidation test according to the e-log p' curve. The results of the UCS test on soil-cement columns indicated that cement content of 20% cured at 180 days could raise the shear strength of cement-admixed kaolin clay up to 4810 % compared to untreated Kaolin clay. However, due to pozzolonic reaction and hydration process, the permeability and final water content were decreased with higher cement content. Re-moulded soil-cement samples were mixed at 81% (1.5 times of liquid limit) base placing of into the mould. To ensure homogeneously mixture were poured into the mould in three layers. In the physical modelling tests, as the area improvement ratio and length / depth ratio increase, the coefficient of volume compressibility, mv and coefficient of compressibility, Cc decrease. At 20% content of cement, mv decreases by 51% for area improvement ratio 30% and length/depth ratio 50%. Analytical modeling was performed to validate and compared the effect of the group columns on the settlement. The homogenization method was employed by actual pressure distribution between the column and surrounding soil. The settlement results were compared with the Japan Institute of Construction Engineering (JICE,1999) approach, homogenization method and also a-ß method. From these methods, the homogenization method presented closest estimation of settlement with more than 75% compatibility with the physical modelling
dc.description.sponsorship	Faculty of Civil Engineering
dc.identifier.uri	https://openscience.utm.my/handle/123456789/1441
dc.language.iso	en
dc.publisher	Universiti Teknologi Malaysia
dc.subject	Soil stabilization—Research
dc.subject	Soil mechanics—Research
dc.subject	Soil cement—Testing
dc.title	Settlement behaviour of soft soil stabilized with soil-cement columns using constant rate of strain method
dc.type	Thesis
dc.type	Dataset

Settlement behaviour of soft soil stabilized with soil-cement columns using constant rate of strain method

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