Evaluation of Lime and Phosphoric Acid Stabilization in Missouri, Route 169, Gentry County. Study 63-1

摘要

The report presents an evaluation of the performance of a flexible pavement on Route 169, Gentry County in Northwest Missouri. The pavement was built in 1961-62, to evaluate the effects of phosphoric acid and lime stabilization of a heavy clay soil. Data available for evaluating the performance of these sections consisted of Benkelman beam deflection measurements, and annual samples of load and traffic variables. The objective evaluation of the acid and lime treated subbases was obtained by analysis of variance. The following findings appear justified: (1) One inch of rolled stone subbase is approximately equivalent to five inches of phosphoric acid treated subbase. (2) Two inches of rolled stone subbase is approximately equivalent to five inches of lime treated subbase. (3) The inner wheelpath is stronger than the outer wheelpath by as much as 50 percent. (4) There is very little difference between spring and fall values of pavement strength. (5) The equivalent thickness of all test sections as built was inadequate to restrict deflections to a tolerable level in the outer wheelpaths after two years service. (6) There appears to be a difinite relationship between pavement deflections and expected service life. (Author)