Comparison of the Effectiveness of Enzyme and Portland Cement for Compressive Strengths of Stabilized Soils

Abstract

Portland cement can be used as soil stabilizer, but poses some problems such as dust pollution, consumption of fossil energy and relatively large amounts of calcium-rich raw materials. Enzyme as a soil enzymatic stabilizer is a natural organic compound and promising material to reduce the application of Portland cement. Perma-Zyme is one type of enzyme. The results of the study showed that soil type and curing method significantly affected the effectiveness of the treatments with Perma-Zyme and Composite Portland cement. Under the air-dry conditions, the unconfined compressive strengths of soils stabilized with Composite Portland cement were lower than those treated with Perma-Zyme at each age. In sealed glass containers, the unconfined compressive strengths of soils treated with Composite Portland cement were higher than those treated with Perma-Zyme. These results indicate that after compaction, the surface of soil stabilized with Portland cement should be moistened with a spray of some water or cover with materials (such as plastic sheet)，but the surface of soil stabilized with Perma-Zyme need not spray water and cover with materials in the actual project construction.