The Road With Cement-based Composite Stabilized Soil Material Preliminary Study

Up to now, the soil stabilization technology has become a crossing subject which combines mechanics, structure analysis, colloid and surface chemistry, and has been used in basic facilities, road construction, dams, sand solidification and so on. The soil stabilizer is an additive which can reactive with the soil and improve the engineering properties of the soil. It was significant in technique and economy to stabilize the soil. The soil reinforcement with soil stabilizer is to make use of the local soil which is abundant and widely distributed as the basic material and the soil mining and manufacturing is easy. It plays a significant role in technology and economy.Based on the achievements of the past generations, in this thesis, two types of soil in Changsha area were selected, then cement, to which water glass, chloride and surfactant were added in a certain proportion, is mostly used to stabilize the two types of soil. According to some experimental methods in the road construction standard, some properties of this soil stabilization were discussed preliminarily, and the main conclusions of the study are as follows:1. Through analyzing the raw materials of cement(A), water glass (B), chloride(C) and surfactant(D) of the nature, as well as studying their mutual reaction mechanism, an appropriate method of making use of these materials to stabilize soil was found. 2. In case of only using B, C and D to stabilize soil, the result of the stabilized soil was not ideal, such as low intensity and water instability. Based on the analysis of A, adding it to the stabilized soil with B and C, to a certain extent, is not only solude the problem of low compressive strength but also increase the compressive strength obviously, which is four times more than the former.3. Using orthogonal design theory, under the condition of the given range, some tests were completed, and we have been optimal formula of the curing agent composed with cement, water glass, chloride and surfactant. The optimal formula is: cement 65%, water glass 25%, chloride 15%, surfactant 0.6%.4. No.1 (clay) and No.2 (silty clay) were consolidated by the volume of 10% curing agent under the optimal formula, and their compressive strength are 0.88Mpa and 1.35Mpa respectively. When they were consolidated by the volume of 10% cement, their compressive strength are 0.78Mpa and 1.28Mpa respectively. Under the condition of the same volume, curing agent under the optimal formula and cement are respectively applied to consolidate soil, the former's compressive strength is slightly higher than the latter.5. Two types of soil were consolidated by 10% curing agent under the Optimal formula. Both of their capability of water stability and tolerance of wet and dry cycle are not very good, but clay is better than silty clay.6. The principle of Fault Tree was applied to analyze direct and indirect causes of the structure damage of subgrade and pavement. The results showed that combined with practice, some effective measures for prevention can be proposed, according to the order and importance of these causes.