"The stabilization of soil has been carried on since early historic times. The Romans used lime and volcanic ash as additives for this purpose. After the discovery of cement and its property of bonding soil particles it became one of the essential additives in the soil stabilization field. Many other kinds of additives have been developed and are being used today for soil stabilization.
A question that arises through the increasing use of stabilizers in soil is whether the changes that are effected are of a temporary or permanent nature. Changes may occur from the degradation of the stabilized soil by climatic changes, moisture movement and others. Among these changes the leaching by water associated with moisture movement can be considered one of the most influential one. The purpose of this investigation is to determine experimentally the effect of leaching, caused by the movement of water through the soil, on the strength characteristic of a soil stabilized by lime and cement additives.
The water penetrating the stabilized soil dissolves a certain portion of the lime. The amount of water and its flow speed in the soil depends upon the existing hydraulic water pressure gradient between the soil layers. The dissolved lime in the stabilized soil is taken away by the water at a rate determined by the above mentioned pressure gradient. Some cement particles may also be carried away by this water. As the result of this removal of lime and cement a detrimental change in the strength of stabilized soil might be expected.
Under highways and foundations it takes a long time for soil to be leached by water. In order to obtain the results of leaching action in a reasonable time in the laboratory the electro-osmosis apparatus was considered as a possible method to force leaching action to expedite the experiments. The only difference between the use of this apparatus and the phenomena of leaching that occurs in soil in nature, is that in the former case Ca⁺⁺ ions of the calcium hydroxide are replaced by the ion particles from the anode during the ion migration whereas, in the later case, this does not happen. The reason for not using the electro-osmosis method in this experiment was that the method takes a long time and it is not definite as to what effect the ions emitted from the anode will have on the strength characteristics of the specimen. The method of leaching selected for use was a wetting and drying action further described under test procedures.
Since the nature of this investigation is more qualitative than quantitative, the results obtained in our experiment are not expected to be exact and hence the results can be considered within the range of natural acceptance.
For this experiment three sets of specimens were prepared each having two, four and six percent of lime. Each set contained four types of specimens having a cement range between 0 and 6 percent increasing by two percent increments. For all lime and cement combinations eight specimens were prepared to use in the triaxial test. Four of these specimens were tested at 0 and 60 pounds per square inch lateral pressure before leaching and the other four specimens were tested at 0 and 60 pounds per square inch lateral pressure after leaching.
To observe the change in the strength of various specimens the results found were compared for each individual lime-cement combination as well as the sets"--Introduction, pages 7-8.
Heagler, John B., 1924-1999
Davidson, Robert F., 1911-1971
Best, John, 1925-2015
Planje, Theodore J., 1919-1980
Civil, Architectural and Environmental Engineering
M.S. in Civil Engineering
Missouri School of Mines and Metallurgy
© 1960 Yurdakul Osman Ulugonul, All rights reserved.
Thesis - Open Access
Library of Congress Subject Headings
Soils -- Leaching
Soils -- Additives -- Testing
Strength of Materials
Print OCLC #
Electronic OCLC #
Link to Catalog Record
Ulugonul, Yurdakul Osman, "Effect of leaching on the strength properties of a hydrated lime-cement stabilized soil." (1960). Masters Theses. 2794.