Effect of Treatment with Cement on the Mechanical Characteristics of Silt from Telagh Region of Sidi Belabes, Algeria

In Algeria the use of soil treated with hydraulic binder is not responded because the very few sites already completed have not experienced feedback to confront the knowledge on the subject. Most soils in their natural condition lack the strength, dimensional stability and durability required for building. These inherent deficiencies may be overcomed through a process of stabilization by mechanical compaction and addition to the soil matrix of chemical binders, such as cement or lime. High water content and low workability of local soils have often caused difficulties for highway construction projects. The addition of a few percentages by weight of cement has shown its effectiveness towards better control of workability during compaction and significant cost savings over removal and replacement of backfill material in some projects (Sariosseiri and Muhunthan in Eng Geol 104:119-125, 2009). This paper is focused on understanding the compaction characteristics and mechanical properties of compacted cement stabilised soil mixtures. We opted to base our work on a laboratory study, conducting soil-cement mixtures. A soil area Telagh was treated with cement varying each time the quantities of cement and water, in order to observe the influence of dosage and the amount of water present in the mixture on compressive strength and the stiffness of the material. In this study, natural silty soil extracted from the locality Guetna of region "Telagh" was characterized and mixed with cement to prepare compacted cylindrical samples to standard Proctor (OMC) of different cement doses and different water-cement ratios. After curing, the hardened samples were tested and their compressive strength was investigated for different duration. Another important parameter is considered in this study is the extent of the permeability of the soils treated with cement, as our material can be used for building dams and dykes. The results of the first part of this study showed the influence of cement content on compaction characteristics and water permeability of stabilized Guetna soil. The results from the second part of this study showed the effect of time lag, water-cement ratios, and dosage of cement on the compressive strength and elastic modulus of the investigated. Salient conclusions of the study are (a) compaction characteristics of soils are affected by the addition of cement, in particular the water content that increases with high doses of cement, (b) compressive strength increased with dosage of cement varying to 2 % at 6 %, even at lower values of cement doses, (c) in contrast, the water contact on soil leads to a marked decrease in compression strength, (d) the results also indicated that the water permeability decrease when le cement content increased, (e) the elastic modulus defined at 50 % of peak strength is determined for studied material at different binder contents and different curing times, (f) the development of elastic modulus is in accordance with compressive strength. A quantitative correlation E-50 = 75. Rc is therefore determined according to large quantities of test results.