Determination of the Optimal Mix Proportions for Basalt Fiber Recycled Asphalt Mixtures Using Response Surface Methodology
In the design of asphalt mixture proportions,when two or more additives are added,the use of Marshall test or orthogonal test method may have limitations.In order to determine the optimal asphalt mixture proportion,a Box-Behnken(BBD)design based on response surface methodology was employed to optimize the gradation of AC-13 type asphalt mixture with the addition of basalt fiber and RAP for hot recycled asphalt mixture.The results indicated that the optimized oil-stone ratio is 5.17%,the reclaimed asphalt pavement(RAP)content is 31.89%,and the basalt fiber content is 0.26%.Experimental validation of the predictive model shows a small relative error(less than 3%)between predicted and measured values,demonstrating that the second-order model established by the BBD method has a good fitting effect.This optimization approach can effectively optimize the mixture proportions of recycled asphalt mixture with basalt fiber and achieve good performance for the hot recycled asphalt mixture under the optimal additive contents.