The Study Of Semi-lfexible Pavement Composite Material And Structure

As early as the middle of the last century, semi-flexible composite pavement isstudied by foreign countries. The road has the characteristics of hardness andsoftness with high strength and good ride comfort which is confirmed in thefollow-up study. In recent years research and application of the road are also carriedout in China, which have achieved good results. A research for design of thepavement materials and stress analysis is launched in this article.In the design of maternal asphalt mixture, this article considers the variable Imethod for aggregate gradation design has different advantages compared to volumemethod which is conditional design methodology, can determine the scope of theaggregate based of the calculation, more specific for the pass rate of each sieve .This article designs the gradation range by variable I method, and then use theorthogonal test to optimize the gradation, determine the applications of the SC16; Inthe cement mortar, carry out experimental analysis through change the singlecomponent, and through mortar performance to determine the impact law of eachingredient, meanwhile, researches the impact law of the content of the fly ash,expansive agent, and water reducing agent; Then carry out the performance test ofheat, cold and water stable through make the Semi-flexible composite specimen, thecomposites showed excellent performance.Using BISAR 3.0 which is made by Shell Company to study stress of pavementstruture when the semi-flexible composite material is used in high grade pavement,and studied out the typical structure layers when semi-flexible composite material isused as surface layer; This paper analysises the stress of these pavement layers fromthickness of surface layer, modulus of composite material and the bonding statebetween surface layer and second layer. We research stess distribution under thisthree different conditions, and find out the the worst load position. We study thesensitivity of three conditions. The thickness and the bonding state effect onpavement very obviously, as a result, they must be considered in the design. Andeffects of the modulus of the composite material is liner, structeral bearing capacityis better with the modulus is increasing.