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Triaxial compression studies of asphalt cement-treated granular materials indicate that each material exhibited a volume decrease during initial phases of stress-strain. The stress-strain curve was nearly linear until the material reached minimum volume, after which curvature increased rapidly. The analysis presented is based on the assumption that the point of minimum volume represents a yield point similar to proportional limit. Deformation moduli, M, were evaluated by applying linear regression analyses to that portion of the effective stress ratio versus strain curves occurring prior to minimum volume, instead of using a tangent or secant modulus. Plots of M versus σ3 were analyzed to determine the relationship between M and the confining pressure, σ3 Poisson's ratio, μ, was evaluated by assuming that volume change is a function of either octahedral or deviator stresses. Results of linear regression analyes showed that deformation moduli will generally tend to increase with increasing lateral constraint. However, statistical analyses of M versus σ3 plots indicated that this relationship is not well defined and in many cases M is essentially constant for the range of lateral pressures studied. By using average values of M, it was found that limestone and dolomitic aggregates treated with asphalt cement have moduli generally greater than gravel. Both method of evaluation of μ gave values generally in the range of 0.36 - 0.44, indicating that volume change was primarily a function of deviator stress.

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Journal Title

Proceedings of the Iowa Academy of Science





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©1969 Iowa Academy of Science, Inc.



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