Bituminous mix characterization for flexible pavements

This paper deals with the characterization procedure for dense graded bituminous concrete mixes recommended for road and airport construction in saudi arabia. The thickness design procedure and the factors governing the desirable structural and surface characteristics of the dense bituminous mixes are also outlined. The mix design in laboratory is based on the marshall method, and the optimization of asphalt content is based on such properties as marshall stability, density, air voids in total mix and voids filled with bitumen. The asphalt concrete mix designs developed for the flexible pavements constructed in recent years at civil airports of gassim, dhahran and jeddah are presented and discussed. The statistical parameters of field quality control data are also presented. The relationship between in-situ air voids and air voids of the compacted marshall specimens is also evaluated. Finally recommendations are made on quality control of the plant mixes for satisfactory achievement of the design mix characteristics in- situ (a).