Optimization and management of materials in earthwork construction

Different earth materials, such as soil and rock, are used in the construction of geotechnical systems including foundations, retaining walls, embankments and road pavements and air-field pavements. Often site soils are unacceptable for the intended function and must be replaced with better quality materials or improved. One method of improvement is to mix high quality site materials with lesser quality site materials to provide an acceptable soil material. In Iowa, materials for earthwork construction are classified, based on their suitability, as: select, suitable, and unsuitable soils. In this study, three unsuitable soils were mixed with one select soil at various proportions (unsuitable : select = 25%:75%, 50%:50% and 75%:25%) to investigate how the engineering properties can be improved at different select-unsuitable ratios and evaluate the potential of using the blends at various embankment layers. Experimental results indicate that resulting blends are for the most part acceptable and classify as suitable materials for embankments. With the large amount of money involved in carrying out the remedial measures for poor soils, management and optimization of the available materials by mixing the materials among themselves in various proportions can be a viable solution