Research documents
The benefits of subgrade stabilization are that it improves the strength, stiffness, and durability of soft subgrade soils. Such improvement allows a reduction in the required thickness of overlying pavement courses and/or an increase in pavement life. Quantifying the life cycle cost benefits requires performing pavement design studies based on anticipated traffic levels, desired serviceability, etc. The preferred design method would be a mechanistic design, which requires resilient modulus values for the stabilized subgrade and other pavement layers. Neither resilient modulus testing nor pavement design studies were included in the scope of the work for this project, but they should be included in subsequent phases.
- The evaluation of clay properties mixed with a new product, natural, ecological, denominated RBI-81;
- The determination of the optimal dosage of the RBI-81 and his/her influence, together to the conditions of seasoning (time, contained of water, etc.), on the mechanical characteristics of the mixtures.
This study, therefore, has experimental theoretical character and is the first one effected in our Country on this new additive.
Brazil paper – effect of curing time
Abstract
This paper address the topic influence of curing time on the unconfined compression strength of three gneiss residual soils from the North Forrest of Minas Gerais, Brazil, after stabilization with the chemical additive called RB1 Grade 81. The soils group encompassed a mature residual soil, named soils 1 (pedologically classified as a Red- Yellow Latossol), and two young residual soils, named soils 2 and 3.
Additive contents used were as follows: 2%, 4% and 6% related to soils dry mass. Data analysis supported the following conclusions: (i) addition of 4% and 6% of RBI Grade 81 to the soils led to significant increases in their unconfined compression; (ii) at 7 days curing time the mixtures exhibited significant unconfined importance of this parameter on the mixtures stabilization process.
Technion Israel– The Use of ANSS as a stabilizer for fine grained swelling soils
This part of the research is aimed at quantifying the affect of ANSS content on the
swelling properties of a clayey soil of high swell potential. The test program included
a set of experiments with the objective to examine the vertical swell of stabilized and
non stabilized specimens as a function of initial water content, applied vertical
pressure and ANSS content. A second phase of experiments was to evaluate the rate of
vertical swell in response to a change in water content as a function of the initial water
content and ANSS content.
Link to the Executive Summary
The Municipality of Tel Aviv Structural Evaluation of Stabilized Shoulders with ANSS
The Elastic Moduli and the CBR of the stabilized natural soil increased significantly as a result of the stabilization. Stabilizing the sub grade has lead to an increase of the Elastic Moduli of the upper layer by more than twice.
The affect of the stabilized layer on the lower non stabilized layers is very clear through analyzing the results using the dual layer model.
The municipality of Tel Aviv paved 5 test sections next to one of the roads within the city in order to evaluate the performance and durability of stabilized layers through their service period and examine the strength development and other characteristics of various pavement materials stabilized with ANSS.It can be concluded that stabilization of the natural soil contributes to the development of strength and function of the stabilized layer. It is also evident that there is a contribution to the total equivalent strength values of the structure of layers.
Link to the Evaluation