Rapid Soils Analysis Kit for Low-Volume Roads and Contingency Airfields

Abstract

The ability to determine the construction requirements for soil without the need to conduct laboratory testing is essential in performing an expedient airfield or highway design. Until now, only subjective field analysis techniques satisfied this requirement, but their results failed to provide tangible numeric data that could be used to determine moisture–density and California bearing ratio (CBR) design criteria. This paper introduces a rapid soils classification kit with instruments that are compact and easily transported to provide an immediate measure of soil moisture, grain-size distribution, and plastic limit. An accompanying software program incorporates the numeric data generated from the soils kit, classifies the soil, and performs multiple regression routines based on a statistical analysis of a large database of soil properties to predict optimum water content and maximum dry density for the soil of interest. Built-in, higher-order regression equations allow the user to visualize complete moisture–density curves for varying compaction energies as well as soaked and unsoaked CBR as functions of water content for the constructed condition of the soil. The moisture–density curve and CBR strength represent the critical data necessary to enable contingency design and construction of highways and airfields.