This paper presents results of an investigation of the effects of phosphoric acid and furfuryl alcohol on the resistance and strengths of a clayey soil and of a sandy soil. Results indicate that greater water resistance and higher strengths can be obtained with both soils by using the admixtures. For the sandy soil, a certain optimum amount of phosphoric acid gives the maximum strengths for all furfuryl alcohol contents. The stabilization mechanism for the clayey soil is thought to be a combination of the formation of phosphoric gels and of a resin product of a furfuryl alcohol polymerization reaction. The mechanism for the sandy soil is the formation of the polymerization resin product
